Popliteal entrapment syndrome

Sidhartha Sinha, MA, MRCS,a Jon Houghton, MRCP, MFSEM,b Peter J. Holt, PhD, FRCS,a Matt M. Thompson, MD, FRCS,a Ian M. Loftus, MD, FRCS,a and Robert J. Hinchliffe, MD, FRCS,a London and Surrey, United Kingdom

Introduction: Popliteal entrapment syndrome (PES) is a rare but important cause of intermittent claudication in young people. Controversy exists about optimal strategies for diagnosis and management, particularly for variants such as functional popliteal entrapment. The aim of this review was to systematically catalog the published English-language literature on PES and to determine if evidence-based guidelines for management could be formulated. Methods: An electronic search using the MEDLINE, EMBASE, Cochrane Library, AMED, and CINAHL databases was performed to identify articles about PES published from 1947 to December 2010. The systematic review conformed to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement standards. Prospective studies and retrospective case series with more than five patients with arterial, venous, nerve, and combined neurovascular entrapment were analyzed on a study-by-study narrative basis. Results: The search identified 291 articles, and 44 were included. Of these, 30 studies were on popliteal artery entrapment syndrome (PAES). No relationship was found between duration of symptoms and the presence of irreversible arterial injury. Each study used a median of three diagnostic tests (range, 1-6). Arteriography was used in 28 of 30 studies to diagnose PAES, with an estimated mean sensitivity of 97% (range, 85%-100%). Twenty-three studies described arterial reconstructive procedures, with a median failure rate of 27.5% (range, 0%-83%). The proportion of patients asymptomatic after surgery was reported in only 12 of 30 studies, with a median value of 77% (range, 70%-100%). Conclusions: A large volume of predominantly retrospective clinical data exists on PES. A subset of studies describe a significant failure rate after surgery, but study quality is insufficient to derive robust conclusions allowing recommenda- tion of any one particular diagnostic modality or operative procedure over another. Improvements in management of this condition are unlikely to result from publication of further retrospective case series, and clinicians should concentrate on prospectively collected data with predefined inclusion criteria, outcome measures, follow-up protocols, and transparent standardized reporting criteria. (J Vasc Surg 2012;55:252-62.)

Intermittent claudication (IC), as a manifestation of progressive injury to the popliteal artery with subsequent atherosclerotic peripheral vascular disease (PVD) in limb loss has been described.3,4 older patients, is a frequently encountered symptom in Although the anatomic basis for entrapment of the vascular surgical practice. However, IC may also be popliteal artery was first described in 1879, the clinical described by a younger subset of patients without any condition associated with such anatomic abnormalities was risk factors for PVD and can present a diagnostic chal- not described until 1958.3 Knowledge of the syndrome— lenge.1 Popliteal entrapment syndrome (PES) describes and of variations in the underlying anatomic abnormalities—was a group of conditions in which compression of the subsequently advanced through sporadic publication of popliteal artery, popliteal vein, and tibial nerve (singly or case reports and small case series.3 The formation of the in combination) in the popliteal fossa by surrounding Popliteal Vascular Entrapment Forum in 1998 was an musculoskeletal structures occurs to a degree sufficient attempt to gain some consensus on the anatomic classifica- to cause vascular and neurogenic symptoms.2 Popliteal tion of the different types of PES (Fig 1), but it was artery entrapment syndrome (PAES) is believed to be acknowledged that the quality of available studies on which responsible for a significant proportion of IC in young to base management guidelines was poor, and attempts at patients and should not be considered benign, because evidence synthesis have previously been through narrative commentary rather than systematic review.3,5 PES can be difficult to differentiate from other causes of From the St George’s Vascular Institute, Londona; and Defence Medical Rehabilitation Centre, Headley Court, Surrey.b exertional lower leg pain in young patients, and proposed Competition of interest: none. management algorithms are complex or based on guide- Additional material for this article may be found online at www.jvascsurg.org. lines for atherosclerotic PVD, with particular inconsisten- Reprint requests: Robert J. Hinchliffe, MD, FRCS, Senior Lecturer, Con- cies in the diagnosis of functional popliteal entrapment.5,6 sultant in Vascular Surgery, St George’s Vascular Institute, 4th Flr, St James Wing, St. George’s Healthcare NHS Trust, Blackshaw Rd, London Furthermore, although open surgery was traditionally recom- SW17 0QT (e-mail: [email protected]). mended as the treatment of choice for PES, the development The editors and reviewers of this article have no relevant financial relationships of endoluminal revascularization (catheter-directed throm- to disclose per the JVS policy that requires reviewers to decline review of any bolysis) and endovascular techniques has fueled interest in manuscript for which they may have a competition of interest. complementary treatment strategies.7,8 As a consequence, 0741-5214/$36.00 Copyright © 2012 by the Society for Vascular Surgery. there remains a lack of consensus regarding the most effec- doi:10.1016/j.jvs.2011.08.050 tive strategy for diagnosis and treatment of PES. The 252 JOURNAL OF VASCULAR SURGERY Volume 55, Number 1 Sinha et al 253

Type I Popliteal artery running medial to the medial head of gastrocnemius

Type II Medial head of gastrocnemiuslaterally attached

Type II Accessory slip of gastrocnemius/fibrous bands arising from medial head of gastrocnemius

Type IV Popliteal artery passing below popliteus muscle/fibrous bands arising from popliteus

Type V Primarily venous entrapment

Type VI Other variants

Type F Functional entrapment

Fig 1. Popliteal Vascular Entrapment Forum classification for popliteal entrapment syndrome (adapted from Di Marzo and Cavallaro,5 figures reproduced from Pillai et al2 with permission).

objective of this study was to systematically categorize the relevant titles and complemented by hand searches of ref- published English-language literature on PES, collate the erence lists of the included articles. The literature review evidence, and determine if evidence-based guidelines for conformed to Preferred Reporting Items for Systematic management could be formulated. Reviews and Meta-analyses (PRISMA) statement stan- dards.9 METHODS Articles that met the inclusion criteria were further A systematic review of PES was performed by electron- classified according to the pathology described (ie, entrap- ically searching the medical literature published from 1947 ment of artery, vein, and/or nerve), and two authors (S.S., to December 2010 using EMBASE Classic, EMBASE, R.H.) independently abstracted the data. Data were col- Ovid-MEDLINE, Ovid-MEDLINE in-process and other lected on patient demographics (age, sex), disease presen- nonindexed citations, AMED, CINAHL, the Cochrane tation (symptoms, laterality), diagnostic adjuncts, type of Database of Systematic Reviews, the Cochrane Database of treatment, duration of follow-up, and outcome measures Controlled Trials, and Elsevier’s ScienceDirect catalog. and summarized in evidence tables as a study-by-study The search strategy was limited to English-language articles narrative. Outcome measures of interest were mortality and used the following terms: “popliteal” adj/adj2/adj3 rates, complication rates (eg, graft failure and amputa- “entrapment” and “popliteal” adj/adj2/adj3 “compres- tions), successful relief of symptoms in operated-on symp- sion” in titles and abstract fields for all databases. In addi- tomatic limbs, successful prevention of symptoms in operated- tion for EMBASE and MEDLINE, the exploded term on asymptomatic limbs, and results for conservatively “popliteal” was combined with the keywords “entrap- managed limbs. ment” and “compression”. Study quality was assessed by examining risk of Inclusion criteria for articles were prospective studies bias using validated Cochrane methodology.10 The qual- and retrospective case series with more than five patients. ity of the study was based on the risks of bias and was We excluded case reports, case series with fewer than five translated into a level of evidence according to the patients, letters, review articles, and commentaries. The Scottish Intercollegiate Guidelines Network (SIGN) in- electronic search results were manually reviewed to retrieve strument.11

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Table I. Summary characteristics/results of the studies included in the systematic review

Patients Limbs Operated Asymptomatic SIGN Study (year) Pathology Study type (No.) (No.) Diagnostic tests used (%) (%) levela

Di Cesare (1994)22 PAES Prospective 6 10 Doppler US/ABPI, MRI, 20 NS/UC 2– DSA Forster (1997)23 PAES Prospective 9 17 Doppler US/ABPI, MRA, 100 NS/UC 2– DSA Greenwood (1986)24 PAES Retrospective 7 12 ETT, PVR, DSA 67 NS/UC 3 Kim (2006)25 PAES Retrospective 12 23 Doppler US/ABPI, MRI, NS/UC NS/UC 3 MRA, CT, CTA, DSA Ozkan (2008)26 PAES Retrospective 6 7 MRI, DSA 83 NS/UC 3 Hai (2008)27 PAES Retrospective 8 11 CTA, MRI, DSA 100 NS/UC 3 Papaioannou PAES Retrospective 16 NS/UC CTA NS/UC NS/UC 3 (2009)28 Anil (2010)29 PAES Retrospective 8 13 CTA 100 NS/UC 3 Zhong (2010)30 PAES Retrospective 9 13 CTA, DSA 100 NS/UC 3 Rich (1979)31 PAES Retrospective 9 14 ETT, Doppler US/ABPI, 100 NS/UC 3 PVR, DSA Ferrero (1980)32 PAES Retrospective 7 7 DSA 100 NS/UC 3 Collins (1989)33 PAES Retrospective 12 20 ETT, DSA 90 73 3 Gyftokostas 199134 PAES Retrospective NS/UC 74 Doppler US/ABPI, DSA 10 NS/UC 3 Zund (1995)35 PAES Retrospective 20 26 Doppler US/ABPI, DSA, 92 NS/UC 3 CT Rosset (1995)36 PAES Retrospective 11 15 DSA, CT, MRI 100 NS/UC 3 Porcellini (1997)37 PAES Retrospective 9 11 Doppler US/ABPI, ETT, 100 91 3 DUS, CTA, MRI, DSA Hoelting 199738 PAES Retrospective 19 23 Doppler US/ABPI, DSA 100 70 3 Di Marzo (1997)39 PAES Retrospective 30 45 Doppler US/ABPI, DUS, 100 76 3 DSA Deshpande (1998)40 PAES Retrospective 8 16 Duplex US, DSA 100 75 3 Lambert (1998)41 PAES Retrospective 17 21 PFR, DUS, MRI, DSA 81 70 3 Davidovich (1999)42 PAES Retrospective 8 9 Doppler US/ABPI, DSA 100 89 3 Levien (1999)43 PAES Retrospective 48 88 Doppler US/ABPI, DUS, 93 NS/UC 3 DSA Ring Jr (1999)44 PAES Retrospective 8 16 DSA 81 NS/UC 3 Andrikopoulos PAES Retrospective 14 18 Doppler US/ABPI, DUS, 100 78 3 (1999)45 MRI, CT, DSA Ohara (2001)46 PAES Retrospective 10 11 Doppler US/ABPI, CT, 100 91 3 DSA Ruppert (2004)47 PAES Retrospective 23 32 Doppler US/ABPI, DSA 100 NS/UC 3 Goh (2005)48 PAES Retrospective 6 8 Doppler US/ABPI, DUS, 100 87.5 3 CTA, MRI, DSA Bustabad 200649 PAES Retrospective 8 12 Doppler US/ABPI, DUS, 83 70 3 MRI/MRA, DSA Gourgiotis (2008)50 PAES Retrospective 38 49 Doppler US/ABPI, DUS, 100 100 3 CT, CTA, DSA Turnipseed (2009)51 PAES Retrospective 57 NS/UC Doppler US/ABPI, PVR, 100 NS/UC 3 DUS, MRA/MRI, DSA Raju 200052 PVES Retrospective 30 NS/UC PVR, DUS, venography 100 48 3 Hirokawa 200253 PVES Retrospective 11 14 Doppler US, DUS, 100 57 3 venography, CT Milleret (2007)54 PVES Retrospective 11 11 Doppler US, DUS, 100 82 3 venography Lane (2009)55 PVES Retrospective NS/UC 49 Duplex US, venography 61 NS/UC 3 Mastaglia (2000)56 NEPF Retrospective 9 9 Nerve conduction studies, 67 100 3 electromyography Psathakis (1991)57 CNVE Retrospective 49 66 Dopper US/ABPI, 62 98 3 venography Pailler (1988)58 Healthy subjects Prospective 107 NS/UC Doppler US/ABPI N/A N/A 2– Leon (1992)59 Healthy subjects Prospective 100 200 Duplex US, PVR N/A N/A 2– Erdoes (1994)60 Healthy subjects Prospective 36 72 Duplex US, MRI, MRA N/A N/A 2– Chernoff (1995)61 Healthy subjects Prospective 13 13 Doppler US/ABPI, MRI/ N/A N/A 2– MRA Akkersdijk (1995)62 Healthy subjects Prospective 16 32 Duplex US N/A N/A 2–

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Table II. Estimate of diagnostic sensitivities for different tests used to assess popliteal artery entrapment syndrome

Studies allowing estimate of Studies describing use of test sensitivity Estimate of sensitivity, % Diagnostic modality No. Ref No. Ref Mean Median (range)

Provocation arteriography 21/30 22-25, 27, 30, 31, 33, 13/21 22-24, 27, 30, 33, 36, 97 100 (85-100) 34, 36-40, 42-45, 37, 39, 40, 42-44 47, 48, 51 Static (or not further 7/30 26, 32, 35, 41, 46, 49, 4/7 26, 32, 46, 50 100 100 (NA) described) arteriography 50 Provocation DUS 10/30 37, 39-41, 43, 45, 48- 3/10 39, 40, 45 83 100 (50-100) 51 Provocation Doppler US/ 18/30 22, 23, 25, 31, 34, 35, 6/18 22, 39, 42, 45, 50, 51 90 100 (50-100) ABPI 37-39, 42, 43, 45- 51 MRI/MRA (provocation 12/30 22, 23, 25-27, 36, 37, 4/12 22, 23, 26, 51 94 100 (76.5-100) and static) 41, 45, 48, 49, 51 CT/CTA (provocation 12/30 25, 27, 28, 29, 30, 3/12 29, 30, 46 100 100 (NA) and static) 35-37, 45, 46, 48, 50 Exercise (treadmill) testing 4/30 24, 31, 33, 37 1/4 33 100 100 (NA) Plethysmography/PVR 3/30 24, 31, 51 1/3 51 100 100 (NA)

ABPI, Ankle-brachial pressure index; CT, computed tomography; CTA, computed tomography angiography; DUS, duplex ultrasound; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging; NA, not applicable; PVR, pulse-volume recording; US, ultrasound. cular (arterial stenosis, occlusion, aneurysmal change, and scribed a median 24% prevalence (range, 6%-86%) of pop- deviated course) and extravascular (abnormal muscle at- liteal artery occlusion, and 15 of 30 studies reported a tachments and muscular hypertrophy) anatomic abnormal- median 13.5% prevalence (range, 4%-36%) of poststenotic ities implicated in arterial entrapment.22,25-29 However, dilatation or aneurysm formation in the popliteal artery. only three studies suggested that cross-sectional imaging— The duration of symptoms before diagnosis was reported in one supporting MRI/MRA and two supporting CT/ 10 of 30 PAES studies and was a median of 12 months 26,28,29 CTA—could replace arteriography as a diagnostic test. (range, 4 hours-120 months).24,29,30,33,35,37,39,44,48,50 No studies directly compared MRI/MRA with CT/CTA No relationship between duration of symptoms and pres- for diagnosis of PAES. ence of irreversible arterial damage (occlusion, poststenotic Imaging in healthy (asymptomatic) individuals. dilatation, or aneurysm formation) was found in the three Popliteal artery occlusion on provocation was demon- studies that reported sufficient patient-level detail to carry strated in a significant proportion of asymptomatic individ- out this analysis (P ϭ .55, P ϭ .17, and P ϭ .64, two-sided uals using different diagnostic modalities. Four studies used Mann-Whitney U test).24,30,48 duplex US imaging to demonstrate popliteal artery occlu- Surgical treatments. Surgical treatment for PAES was sion on provocation in a median of 56% of asymptomatic described in 28 of 30 studies. The two studies that did not individuals (range, 7.1%-80%).60,62-64 One study demon- describe whether surgery was performed were both retro- strated popliteal artery occlusion on provocation in 69% of spective case series with a focus on diagnostics.25,28 An asymptomatic individuals using Doppler US (ABPI) and exclusively posterior approach to the popliteal fossa was MRA.61 No significant differences in the prevalence of used in five studies.31,33,34,37,46 Three studies described popliteal artery compression were found between “ath- using the medial approach more frequently than the poste- letic” and “nonathletic” asymptomatic individuals, al- 40,43,51 though it is noteworthy that definitions of “athleticism” rior approach. Studies that advocated both ap- were based on unclear, subjective, or self-reported crite- proaches tended to acknowledge the superiority of the ria.58,60,62-64 posterior approach for exposing popliteal fossa anatomy Two studies reported differing prevalences of popliteal and reported use of the medial approach only when an vein compression in the asymptomatic population detected arterial bypass procedure was anticipated, although there by duplex US imaging on provocation (20.5% and were no descriptions of protocolized care pathways. After 100%).59,60 The two prospective studies that used provo- musculotendinous division to release the entrapment, only cation MRI/MRA to compare asymptomatic with symp- one study described reattachment of the gastrocnemius tomatic patients found high prevalences of significant pop- muscle compared with eight studies that did not reattach liteal artery (25%) and vein (37.5%) compression in it.31,33,34,37,39,40,46,49,50 Of the 30 studies on PAES, 23 asymptomatic individuals.22,23 described arterial reconstructive procedures (Fig 5). The Disease progression. For all modes of presentation four PVES case series described decompressive surgery (acute and chronic), 24 of the 30 studies on PAES de- (fasciotomy with or without musculotendinous section),

JOURNAL OF VASCULAR SURGERY 260 Sinha et al January 2012 described a 0% reoperation rate for functional entrapment, in the four limbs with functional entrapment also described it also reported that Ͼ50% of patients undergoing surgery arterial occlusion in three other limbs with functional en- for functional entrapment required precedent or subse- trapment. Evidence to guide the management of asymp- quent fasciectomy for chronic compartment syndrome.51 tomatic limbs diagnosed with entrapment is also lacking. This systematic review has revealed that although a Outcomes are only available for six asymptomatic limbs significant volume of material on PES has been published, that underwent surgery, with no report of new symptoms in the quality of available evidence on which to base guidelines the treated limbs. is poor. Included studies were noted to be at risk of bias, Only one study described a conservatively managed and significant variability was found in the reporting of key asymptomatic limb but did not present outcomes for it. outcome measures. Most of the included studies were on Our unit does not currently carry out popliteal fossa de- PAES and PVES, and although venous entrapment can compression on asymptomatic limbs diagnosed with en- coexist with arterial entrapment, the case series on PVES trapment or on symptomatic limbs without concurrent described a predominantly female patient cohort compared objective (ie, postexercise test ABPI drop) or radiologic with the studies on PAES. Tibial nerve entrapment was evidence of concurrent arterial compression. Such patients described in one case series that reported equivalent results enter a graded physical rehabilitation program and are in both surgically treated and conservatively managed pa- assessed using the same follow-up protocol as surgically tients.56 A separate series on combined neurovascular en- treated patients. trapment was described by one author and termed popliteal Publication of further retrospective case series on PES is “pseudoentrapment” syndrome.57 We think it noteworthy unlikely to result in improvements in management and that no other researchers have since described this condi- outcome. Given the rarity of the condition and the diffi- tion and that key features of the “pseudoentrapment” culty in accumulating significant numbers of cases, patients syndrome, such as associated entrapment of the tibial with suspected PES should be referred to large vascular nerve, have been described as variants of PAES.31 centers for management to allow build-up of expertise and Although estimates of sensitivity were gleaned for some greater coherence in data collection. Future attempts at diagnostic tests, clinicians should interpret these with care data collection should be done prospectively with pre- given the inconsistent reporting of numbers of limbs defined inclusion and exclusion parameters, outcome mea- screened, inconsistent reporting of test results and opera- sures, follow-up protocols, and standardized reporting cri- tive confirmation at patient level, and the lack of a univer- teria to maximize their value.67 sally accepted reference standard for diagnosis. In particu- The deficiencies in reporting identified by this system- lar, there was a dearth of data on negative surgical atic review have directed our unit to focus on a number of explorations preventing calculation of specificity for diag- parameters. We now maintain a prospective database that nostic tests. Our unit currently investigates all patients clearly records the number of patients screened. Both lower bilaterally with APBIs before and after exercise testing and limbs are assessed in patients who enter the investigative noninvasive compartment pressure measurements, static pathway. Symptoms, results of investigations, and operative MRI/MRA, and provocation arteriography, with results results are reported by limb and not by patient, with the discussed at a specialized vascular multidisciplinary team reasons for not operating on a limb clearly recorded. Re- meeting. sults of all surgical explorations (positive and negative) are Insufficient evidence was gathered to demonstrate su- entered into the database. periority of any one operative treatment over another, Our postoperative follow-up protocol is defined a pri- although alternative treatments for PAES, such as catheter- ori and consists of a graded physical rehabilitation program, directed thrombolysis, did not seem to obviate the need for a postprocedure exercise test at 6 weeks, and a telephone subsequent surgery. However, challenging the traditional consultation at 3, 6, and 12 months, with deviations from dogma that symptomatic PAES should always be managed protocol (eg, readmissions due to recurrent symptoms) surgically, this review has found that a subset of studies prospectively recorded. Our primary outcome measures are describe a significant rate of failure (both arterial surgical patient oriented (numbers asymptomatic after surgery or reconstruction failure and failure to cure symptoms), which returning to presymptom level of activities or both) and are underscores the need for protocolized management path- supplemented with validated preoperative and postopera- ways based on the best available evidence. tive quality-of-life questionnaire scores (Short Form 36- Outcomes for nonoperative management of symptom- Item Health Survey and Walking Impairment Question- atic PAES were reported for only eight limbs, with sponta- naire).68 We believe that objective and pragmatic evidence neous symptom resolution noted in five limbs (one limb of effectiveness is critical (such as postsurgery exercise test- with anatomic entrapment and four limbs with functional ing) rather than surrogate clinical end points (such as graft entrapment). Robust recommendations on conservative patency rates). Although surgical complications are notori- management strategies for anatomic or functional symp- ously variably reported, we support the use of published tomatic entrapments cannot be made, however, because classification systems to improve comparability and gener- one of the eight limbs with an anatomic entrapment pre- alizability of data.69 sented later with advanced ischemia requiring amputation, Units should aim to collect complete outcome data for while the same study which described symptom resolution all four groups: symptomatic surgically treated limbs, con- JOURNAL OF VASCULAR SURGERY Volume 55, Number 1 Sinha et al 261

servatively managed symptomatic limbs, asymptomatic surgi- 2. Pillai J. A current interpretation of popliteal vascular entrapment. J Vasc cally treated limbs, and asymptomatic conservatively man- Surg 2008;48(Suppl 1):61S-5S. aged limbs. Given the differing definitions of functional 3. Levien LJ. Popliteal artery entrapment syndrome. Semin Vasc Surg 2003;16:223-31. entrapment and differing opinions about the nature of 4. Casscells SW, Fellows B, Axe MJ. Another young athlete with intermit- progression of the condition, particular efforts are needed tent claudication. A case report. Am J Sports Med 1983;11:180-2. to gather data for this subgroup. It is unreasonable to 5. Di Marzo L, Cavallaro A. Popliteal vascular entrapment. World J Surg expect international consensus on controversial areas such 2005;29(Suppl 1):S43-45. as the definition of functional entrapment, but it is crucial 6. Pell RF 4th, Khanuja HS, Cooley GR. Leg pain in the running athlete. J Am Acad Orthop Surg 2004;12:396-404. that studies clearly report the definitions and classification 7. Meier TO, Schneider E, Amann-Vesti B. Long-term follow-up of systems that they do use. Eventual consensus on definition patients with popliteal artery entrapment syndrome treated by endolu- may only be possible in the future after comparison of minal revascularization. VASA 2010;39:189-95. outcomes between different studies, but this will only be 8. Di Marzo L, Cavallaro A, O’Donnell SD, Shigematsu H, Levien LJ, feasible if data are reported in a transparent and standard- Rich NM. Endovascular stenting for popliteal vascular entrapment is not recommended. Ann Vasc Surg 2010;24:1135.e1131-1135.e1133. ized manner. 9. Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis This systematic review is at risk of bias given that search JP, et al. The prisma statement for reporting systematic reviews and strategies were limited to English-language articles. 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Popliteal entrapment as a result of neuro- to influence outcome.71 The rationale for excluding these vascular compression by the soleus and plantaris muscles. J Vasc Surg 1992;15:285-94. smaller series was to collate the experiences of centers that 13. Turnipseed WD. Popliteal entrapment syndrome. J Vasc Surg 2002;35: have treated several patients rather than those with only 910-5. isolated experiences, and the threshold of more than five 14. Cavallaro A, Di Marzo L, Gallo P. Popliteal artery entrapment - analysis patients allowed retention of an acceptable number of of the literature and report of personal experience. Vasc Surg 1986;20: studies. Lowering the threshold to include case series with 404-23. 15. Di Marzo L, Cavallaro A, Sciacca V, Mingoli A, Tamburelli A. Surgical five patients would have resulted in the addition of only five treatment of popliteal artery entrapment syndrome: a ten-year experi- more articles (all on PAES). ence. Eur J Vasc Surg 1991;5:59-64. 16. Di Marzo L, Cavallaro A, Sciacca V, Mingoli A, Stipa S. Natural history CONCLUSIONS of entrapment of the popliteal artery. J Am Coll Surg 1994;178:553-6. 17. Levien LJ, Veller M, Dalichau H, Mohr FW. Popliteal artery entrap- This systematic review has catalogued a large volume of ment syndrome. Cardiovasc Surg 1997;5(Suppl 1):134-5. primarily retrospective clinical data on PES. Although a 18. Bouhoutsos J. Popliteal artery entrapment syndrome: report of 29 subset of studies suggests a significant failure rate after cases. Vasc Surg 1980;14:365-74. surgery, there is insufficient evidence to clearly recommend 19. Bouhoutsos J, Daskalakis E. Muscular abnormalities affecting the pop- one diagnostic modality or operative procedure over an- liteal vessels. Br J Surg 1981;68:501-6. 20. Schurmann G, Mattfeldt T, Hofmann W, Hohenberger P, Allenberg other. Clinicians should henceforth concentrate on pro- JR. The popliteal artery entrapment syndrome: presentation, morphol- spectively collected data with predefined inclusion criteria, ogy and surgical treatment of 13 cases. Eur J Vasc Surg 1990;4:223-31. outcome measures, and follow-up protocols, as well as 21. Psathakis DN. A new syndrome: the pseudo-entrapment of the popli- transparent standardized reporting criteria. teal artery and tibial nerve. Int Angiol 1991;10:250-6. 22. Di Cesare E, Marsili L, Marino G, Masciocchi C, Morettini G, Spartera AUTHOR CONTRIBUTIONS C, et al. Stress MR imaging for evaluation of popliteal artery entrap- ment. J Magn Reson Imaging 1994;4:617-22. Conception and design: RH, JH, IL, SS 23. Forster BB, Houston JG, Machan LS, Doyle L. Comparison of two- Analysis and interpretation: SS, RH, JH dimensional time-of-flight dynamic magnetic resonance angiography Data collection: SS, RH with digital subtraction angiography in popliteal artery entrapment syndrome. Can Assoc Radiol J 1997;48:11-8. 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28. Papaioannou S, Tsitouridis K, Giataganas G, Rodokalakis G, Kyriakou 52. Raju S, Neglen P. Popliteal vein entrapment: a benign venographic V, Papastergiou Ch, et al. Evaluation of popliteal arteries with CT feature or a pathologic entity? J Vasc Surg 2000;31:631-41. angiography in popliteal artery entrapment syndrome. Hippokratia 53. Hirokawa M, Iwai T, Inoue Y, Sato S. Surgical treatment of popliteal 2009;13:32-7. vein entrapment causing symptoms. Phlebology 2002;17:103-7. 29. Anil G, Tay KH, Howe TC, Tan BS. Dynamic computed tomography 54. Milleret R. Popliteal vein entrapment: an unrecognized cause of failure angiography: role in the evaluation of popliteal artery entrapment in surgery for superficial venous insufficiency. Phlebolymphology 2007; syndrome. Cardiovasc Interv Radiol 2011;34:259-70. 14:31-6. 30. Zhong H, Liu C, Shao G. Computed tomographic angiography and 55. Lane RJ, Cuzzilla ML, Harris RA, Phillips MN. Popliteal vein compres- digital subtraction angiography findings in popliteal artery entrapment sion syndrome: obesity, venous disease and the popliteal connection. syndrome. J Comput Assist Tomogr 2010;34:254-9. Phlebology 2009;24:201-7. 31. Rich NM, Collins GJ, Junior, McDonald PT, Kozloff L, Clagett GP, 56. Mastaglia FL. Tibial nerve entrapment in the popliteal fossa. Muscle Collins JT. Popliteal vascular entrapment. Its increasing interest. Arch Nerve 2000;23:1883-6. Surg 1979;114:1377-84. 57. Psathakis DN. A new syndrome: the popliteal pseudo-entrapment. Vasc 32. Ferrero R, Barile C, Bretto P. Popliteal artery entrapment syndrome - Surg 1991;25:214-23. report on seven cases. J Cardiovasc Surg 1980;21:45-52. 58. Pailler JL, Darrieus H, Javita H, Pons F, Aubert P, Sauvageon X. 33. Collins PS, McDonald PT, Lim RC. Popliteal artery entrapment: an Doppler velocimetry in the early detection of the popliteal artery evolving syndrome. J Vasc Surg 1989;10:484-90. entrapment syndrome. Sci Sports 1988;3:271-5. 34. Gyftokostas D, Koutsoumbelis C, Mattheou T, Bouhoutsos J. Post 59. Leon M, Volteas N, Labropoulos N, Hajj H, Kalodiki E, Fisher C, et al. stenotic aneurysm in popliteal artery entrapment syndrome. J Cardio- Popliteal vein entrapment in the normal population. Eur J Vasc Surg vasc Surg 1991;32:350-2. 1992;6:623-7. 35. Zünd G, Brunner U. Surgical aspects of popliteal artery entrapment 60. Erdoes LS, Devine JJ, Bernhard VM, Baker MR, Berman SS, Hunter syndrome: 26 years of experience with 26 legs. VASA 1995;24:29-33. GC. Popliteal vascular compression in a normal population. J Vasc Surg 36. Rosset E, Hartung O, Brunet C, Roche PH, Magnan PE, Mathieu JP, 1994;20:978-86. et al. Popliteal artery entrapment syndrome. Anatomic and embryologic 61. Chernoff DM, Walker AT, Khorasani R, Polak JF, Jolesz FA. Asymp- bases, diagnostic and therapeutic considerations following a series of 15 tomatic functional popliteal artery entrapment: demonstration at MR cases with a review of the literature. Surg Radiol Anat 1995;17:161-9. imaging. Radiology 1995;195:176-80. 37. Porcellini M, Selvetella L, Bernardo B, Del Viscovo L, Parisi B, Baldas- 62. Akkersdijk WL, de Ruyter JW, Lapham R, Mali W, Eikelboom BC. sarre M. Popliteal artery entrapment syndrome: diagnosis and manage- Colour duplex ultrasonographic imaging and provocation of popliteal ment. G Chir 1997;18:182-6. artery compression. Eur J Vasc Endovasc Surg 1995;10:342-5. 38. Hoelting T, Schuermann G, Allenberg JR. Entrapment of the popliteal 63. Hoffmann U, Vetter J, Rainoni L, Leu AJ, Bollinger A. Popliteal artery artery and its surgical management in a 20-year period. Br J Surg compression and force of active plantar flexion in young healthy volun- 1997;84:338-41. teers. J Vasc Surg 1997;26:281-7. 39. Marzo L, Cavallaro A, Mingoli A, Sapienza P, Tedesco M, Stipa S. 64. de Almeida MJ, Bonetti Yoshida W, Habberman D, Medeiros EM, Popliteal artery entrapment syndrome: the role of early diagnosis and Giannini M, Ribeiro de Melo N. Extrinsic compression of popliteal treatment. Surgery 1997;122:26-31. artery in asymptomatic athlete and non-athlete individuals. A compar- 40. Deshpande A, Denton M. Functional popliteal entrapment syndrome. ative study using duplex scan (color duplex sonography). Int Angiol AustNZJSurg 1998;68:660-3. 2004;23:218-29. 41. Lambert AW, Wilkins DC. Popliteal artery entrapment syndrome: 65. Pillai J, Levien LJ, Haagensen M, Candy G, Cluver MD, Veller collaborative experience of the joint vascular research group. Br J Surg MG. Assessment of the medial head of the gastrocnemius muscle in 1998;85:1367-8. functional compression of the popliteal artery. J Vasc Surg 2008;48: 42. Davidovich L, Lotina S, Kostic D, Mikic A, Pavlovic S, Vojnovic B, et al. 1189-96. Popliteal artery entrapment. Asian J Surg 1999;22:173-6. 66. Rignault DP, Pailler JL, Lunel F. The “functional” popliteal entrap- 43. Levien LJ, Veller MG. Popliteal artery entrapment syndrome: more ment syndrome. Int Angiol 1985;4:341-3. common than previously recognized. J Vasc Surg 1999;30:587-98. 67. Albrecht J, Meves A, Bigby M. Case reports and case series from Lancet 44. Ring DH Jr, Haines GA, Miller DL. Popliteal artery entrapment syn- had significant impact on medical literature. J Clin Epidemiol 2005;58: drome: arteriographic findings and thrombolytic therapy. J Vasc Interv 1227-32. Radiol 1999;10:713-21. 68. Momsen H, Bach Jensen M, Norager CB, Roerbæk Madsen M, 45. Andrikopoulos V, Papacharalambous G, Antoniou I, Panoussis P. The Vestersgaard-Andersen T, Lindholt JS. Quality of life and functional popliteal artery entrapment syndrome. Vasc Surg 1999;33:357-65. 46. Ohara N, Miyata T, Oshiro H, Shigematsu H. Surgical treatment for status after revascularization or conservative treatment in patients with popliteal artery entrapment syndrome. Cardiovasc Surg 2001;9:141-4. intermittent claudication. Vasc Endovasc Surg 2011;45:122-9. 47. Ruppert V, Verrel F, Geppert SN, Sadeghi-Azandaryani M, Burklein D, 69. Dindo D, Clavien PA. What is a surgical complication? World J Surg Steckmeier B. Results of perioperative measurements of ankle-brachial 2008;32:939-41. index in popliteal artery entrapment syndrome. J Vasc Surg 2004;39: 70. Chambers D, Rodgers M, Woolacott N. Not only randomized con- 758-62. trolled trials, but also case series should be considered in systematic 48. Goh BK, Tay KH, Tan SG. Diagnosis and surgical management reviews of rapidly developing technologies. J Clin Epidemiol 2009;62: of popliteal artery entrapment syndrome. AustNZJSurg 2005;75: 1253–60.e1254. 869-73. 71. Stein K, Dalziel K, Garside R, Castelnuovo E, Round A. Association 49. Bustabad MR, Ysa A, Pérez E, Merino J, Bardon F, Vela P, et al. between methodological characteristics and outcome in health technol- Popliteal artery entrapment: eight years experience. EJVES Extra 2006; ogy assessments which included case series. Int J Technol Assess Health 12:43-51. Care 2005;21:277-87. 50. Gourgiotis S, Aggelakas J, Salemis N, Elias C, Georgiou C. Diagnosis and surgical approach of popliteal artery entrapment syndrome: a ret- rospective study. Vasc Health Risk Manag 2008;4:83-8. Submitted May 4, 2011; accepted Aug 21, 2011. 51. Turnipseed WD. Functional popliteal artery entrapment syndrome: a poorly understood and often missed diagnosis that is frequently mis- Additional material for this article may be found online treated. J Vasc Surg 2009;49:1189-95. at www.jvascsurg.org. oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix I (online only). Included prospective studies on popliteal vein entrapment

Outcomes ϩ Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention follow-up level

Di Cesare (1994)22 8 asymptomatic Asymptomatic subjects: Asymptomatic subjects’ MRI Surgery 2/10 (those with Outcomes measures Free from risk of bias? subjects (16 limbs) provocation MRI findings: no anatomic positive Doppler US, NS used in 8/8 subjects abnormalities found but MRI, and (16 limbs) PV compression on arteriography), no provocation ϭ 37.5% surgery 8/10 (reasons unclear) Case-control study Mean age 29.1 (range, Symptomatic patients: Symptomatic patients’ MRI Surgical approach NS Follow-up duration: Baseline imbalance: 21-34) yrs, 4M:4F provocation Doppler findings: type I ϭ 10%, NS no US used in 6/6 type II ϭ 10%, functional ϭ patients (unclear if all 40%, variants ϭ 20%, no patients assessed anatomic abnormalities bilaterally, 9 limbs found but PV compression positive) on provocation ϭ 20% Evaluating 6 patients (10 limbs) Provocation MRI used Heidelberg classification Muscle/band section 2/ Loss to follow-up: Blinding of assessors: provocation MRI with PAES in 6/6 patients 2 (100%) NS no for diagnosis of (unclear if all patients PAES assessed bilaterally, 8 limbs positive) Single-center (Italy) Mean age 37.3 (range, Provocation Follow-up tests: NS Partial verification: no 22-50) yrs, 3M:3F arteriography used for 2/6 patients (unclear if patients assessed bilaterally, 2 limbs positive) Study period: NS 4/6 (67%) patients Provocation maneuvers: Differential symptomatic plantar flexion verification: no bilaterally Duration of Incomplete outcome symptoms: NS data: no PVD risk factors in Selective outcome 0/14 patients reporting: no Source of funding: unclear Academic: yes

SIGN level of al et Sinha evidence: 2– Forster (1997)23 8 asymptomatic Asymptomatic subjects: Asymptomatic subjects’ MRA Surgery 17/17 Outcome measures: Free from risk of bias? subjects (16 limbs) provocation MRA findings: no stenosis (75%), NS used in 8/8 (16 1%-50% stenosis (25%) limbs) 262.e1 262.e2 ih tal et Sinha

Appendix I (online only). Continued

Outcomes ϩ Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention follow-up level

Case-control study Mean age 33.4 (range, Symptomatic patients: Symptomatic patients’ MRA Surgical approach NS Follow-up duration: Baseline imbalance: 25-37) yrs, 4M:4F ABPI and Doppler findings: 1%-50% stenosis NS no US (frequency of use (23.5%), 51%-75% stenosis and accuracy unclear) (23.5%), 76%-99% stenosis (23.5%), Ͼ99% stenosis (29%) Evaluating 9 patients (17 limbs) Provocation DSA used Symptomatic patients’ DSA Muscle/band section 17/ Loss to follow-up: Blinding of assessors: provocation MRA with PAES in 9/9 patients (17/ findings: 51%-75% stenosis 17 (100%) NS yes vs DSA for 18 limbs assessed) (12%), 76%-99% stenosis diagnosis of PAES (23.5%), Ͼ99% stenosis (65%) Single center Mean age 20.7 (range, Provocation MRA used Anatomic types described Follow-up tests: NS Partial verification: no (Canada) 14-34) yrs, 2M:7F in 9/9 patients (17/ 18 limbs assessed) Sudy period: 9-mo 8/9 (89%) of patients 41% agreement between Classification system NS Differential recruitment symptomatic MRA and DSA verification: no bilaterally Duration of Provocation maneuvers: Incomplete outcome symptoms: NS plantar flexion data: unclear PVD risk factors: NS Selective outcome reporting: yes Source of funding: unclear

Academic: yes SURGERY VASCULAR OF JOURNAL SIGN level of evidence: 2–

DSA, Digital subtraction arteriography; MRA, magnetic resonance angiography; PAES, popliteal artery entrapment syndrome; SIGN, Scottish Intercollegiate Guidelines Network; MRI, magnetic resonance imaging; NS, not stated or not specified; PV, popliteal vein; US, ultrasound. aur 2012 January oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix II (online only). Included retrospective case-series on popliteal artery entrapment syndrome with a focus on diagnostics

Outcomes ϩ Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Follow-Up level

Greenwood 7 patients, 12 limbs Bilateral post-treadmill Types described anatomically 1/7 (14%) of patients had Outcome measures: Free from risk of bias? (1986)24 test ABPI used in but classification system NS initial thrombolysis (still NS 7/7 patients (11/14 required surgery) limbs positive) Single center (USA) 5/7 (71%) of patients Provocation PVR used Occluded artery in 1/12 (8%) Surgery 8/12 (67%), no Outcome for Incomplete outcome diagnosed with in 4/7 patients (7/8 surgery 4/12 (33%) asymptomatic data: no bilateral PAES limbs positive) [reasons unclear] limb unclear Study period: 1980- 4/5 symptomatic Provocation No relationship to duration Surgical approach NS Follow-up duration: Selective outcome 1985 bilaterally arteriography used in of symptoms NS reporting: no 7/7 patients (13 limbs, 12/13 limbs positive) Mean age 30.6 (range, Provocation maneuvers: Surgical procedures NS Loss to follow-up: Source of funding: 22-56) yrs, 6M:1F plantar flexion NS unclear Presenting symptoms Follow-up tests: NS Academic: yes by limb: IC 9/12 (75%), acute ischemia 2/12 (17%) Duration of symptoms SIGN level of 5 days-120 mos evidence: 3 1/12 (8%) of limbs asymptomatic (not operated) PVD risk factors NS Kim (2006)25 12 patients, 23 limbs ABPI and provocation Type II ϭ 26%, type III ϭ No. operated unclear Outcome measures: Free from risk of bias? Doppler US used in 22%, type V ϭ 4%, NS all patients (accuracy functional ϭ 9%, variants ϭ unclear) 34%, no abnormality ϭ 4% Single center (S. 11/12 (92%) of MRI used in 12/12 8 coexisting venous Surgical approach NS Outcome for Incomplete outcome Korea) patients diagnosed patients (21 limbs, entrapments asymptomatic data: no with bilateral PAES 20/21 limbs positive) limbs unclear Study period: 1995- 7/11 symptomatic CT used in 5/12 Whelan-Rich classification Surgical procedures Follow-up duration: Selective outcome 2005 bilaterally patients (10 limbs, unclear NS reporting: unclear 10/10 limbs positive) Mean age 25 (range, Bilateral provocation Occluded artery in Loss to follow-up: Source of funding: 18-54) yrs, 12M:0F MRA used in 4/12 5/23 (22%) NS unclear al et Sinha patients (8 limbs, 4/8 limbs positive) Presenting symptoms Bilateral provocation Follow-up tests: NS Academic: yes by limb: NS CTA used in 5/12

patients (10 limbs, 262.e3 8/10 limbs positive) 262.e4 Appendix II (online only). Continued

Outcomes ϩ Risk of bias/SIGN

Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Follow-Up level al et Sinha

Presenting symptoms Bilateral provocation SIGN level of by patient: IC 12/ DSA used in 5/12 evidence: 3 12 (100%) patients (10 limbs, 8/10 limbs positive) Duration of symptoms Provocation maneuvers: NS plantar flexion and dorsiflexion 4/23 (17%) of limbs asymptomatic (number operated unclear) PVD risk factors NS Ozkan (2008)26 6 patients, 7 limbs MRI used in 6/6 Type II ϭ 43%, type III ϭ 2/6 (33%) of patients had Outcome measures: Free from risk of bias? patients (NS if 57% initial thrombolysis and NS dynamic scan, unclear PTA (1/2 then had if all patients assessed muscle/band section, bilaterally) -7 limbs 1/2 refused positive decompressive surgery) Single center 1/6 (17%) of patients DSAused in 6/6 Whelan-Rich classification Surgery 5/6 (83%), no Recurrent Incomplete outcome (Turkey) diagnosed with patients (NS if surgery 1/6 (17%) thrombosis data: unclear bilateral PAES dynamic test, unclear [patient refusal] requiring bypass if all patients assessed surgery in 1/7 bilaterally): 7 limbs limbs initially positive treated with thrombolysis (and initial decompressive surgery refused by patient) Study period: NS 1/1 symptomatic NB–MRI considered Occluded artery in 4/7 (57%) Surgical approach NS Follow-up duration: Selective outcome bilaterally diagnostic in 7/7 unclear reporting: unclear limbs, DSA considered diagnostic SURGERY VASCULAR OF JOURNAL in 2/7 limbs Mean age 36 (range, PSD/aneurysm in 2/7 (29%) Bypass surgery (not Loss to follow-up: Source of funding: 17-50) yrs, 5M:1F described further) 4/ unclear unclear 6 (67%), muscle/band Section 1/6 (17%) Presenting symptoms Follow-up tests: NS Academic: yes by limb: IC 6/7 (86%), acute ischemia 1/7 (14%) 2012 January Duration of symptoms SIGN level of NS evidence: 3 PVD risk factors NS oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL Appendix II (online only). Continued

Outcomes ϩ Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Follow-Up level

Hai (2008)27 8 patients, 11 limbs Static CTA used in 7/8 Type I ϭ 36%, type II ϭ All operated (11/11) Outcome measures: Free from risk of bias? patients (unclear if all 45%, type III ϭ 18% NS patients assessed bilaterally): 10 limbs positive Single center 3/8 (37.5%) of Static MRI used in 3/8 Whelan-Rich classification Surgical approach NS Outcome for Incomplete outcome (China) patients diagnosed patients (unclear if all asymptomatic data: unclear with bilateral PAES patients assessed operated limbs bilaterally) Ϫ4 limbs unclear positive Study period: 2003- 1/3 symptomatic Bilateral biplanar Occluded artery in Surgical procedures NS Follow-up duration: Selective outcome 2007 bilaterally provocation DSA 5/11 (45%) NS reporting: no used in 8/8 patients (16 limbs, 10/16 limbs positive) Mean age 32 (range, Provocation maneuvers: PSD/aneurysm in Loss to follow-up: Source of funding: 16-64) yrs, 6M:2F plantar flexion and 2/11 (18%) NS unclear dorsiflexion Presenting symptoms Follow-up tests: NS Academic: no by limb: IC 5/11 (45%), rest pain 1/11 (9%), calf swelling 2/11 (18%), acute ischemia 1/11 (9%) Duration of symptoms SIGN level of NS evidence: 3 2/11 (18%) of limbs asymptomatic (all operated) PVD risk factors NS Papaioannou 16 patients, number of Provocation CTA used Types NS No. operated NS Outcome measures: Free from risk of bias? (2009)28 limbs unclear in 16/16 patients NS (unclear if all patients assessed bilaterally, 13/16 patients showed evidence of vascular compression) al et Sinha Single center Incidence of bilateral Provocation maneuvers: 1 coexistent venous Surgical approach NS Follow-up duration: Incomplete outcome (Greece) cases unclear knee hyperextension entrapment NS data: no Study period: 2002- Mean age 26 (range, Classification system NS Surgical procedures NS Loss to follow-up: Selective outcome 2007 18-72) yrs, 9M:7F NS reporting: no

Presenting symptoms Occluded artery in 1 limb Follow-up tests: NS Source of funding: 262.e5 by limb or patient: (denominator unclear) unclear unclear 262.e6

Appendix II (online only). Continued

Outcomes ϩ Risk of bias/SIGN al et Sinha Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Follow-Up level

Duration of symptoms Academic: yes NS PVD risk factors NS SIGN level of evidence: 3 Anil (2010)29 8 patients, 13 limbs Bilateral provocation Type I ϭ 15%, type II ϭ 8%, All operated (13/13) Outcome measures: Free from risk of bias? CTA used in 8/8 type III ϭ 38%, functional ϭ NS patients (16 limbs, 23%, variants ϭ 15% 13/16 limbs positive) No. of centers 5/8 (62.5%) of NB–CTA considered Whelan-Rich classification Surgical approach NS Outcome for Incomplete outcome unclear patients diagnosed diagnostic in 13/13 asymptomatic data: unclear (Singapore) with bilateral PAES limbs operated limbs unclear Study period: 2002- 2/5 symptomatic Provocation maneuvers: Occluded artery in Muscle/band section only Follow-up duration: Selective outcome 2009 bilaterally plantar flexion 4/13 (31%) 10/13 (77%), bypass NS reporting: no graft 2/13 (15%), “microvascular graft” ϩ muscle/band section 1/13 (8%) Mean age 31 (range, Relationship to duration of Loss to follow-up: Source of funding: 22-46) yrs, 7M:1F symptoms unclear NS yes Presenting symptoms Follow-up tests: NS Academic: unclear by limb: IC 8/13 (61%), atypical pain 1/13 (8%), rest pain 1/13 (8%) Duration of symptoms SIGN level of 3-60 mos evidence: 3 3/13 (23%) of limbs asymptomatic (all operated)

PVD risk factors SURGERY VASCULAR OF JOURNAL unclear Zhong (2010)30 9 patients, 13 limbs Static CTA used in 9/9 Type I ϭ 46%, type II ϭ All operated (13/13) Outcome measures: Free from risk of bias? patients (unclear if all 38%, type III ϭ 15% NS patients assessed bilaterally): 13 limbs positive Single center 4/9 (44%) of patients Bilateral biplanar Whelan-Rich classification Surgical approach NS Outcome for Incomplete outcome (China) diagnosed with provocation DSA asymptomatic data: no

bilateral PAES used in 9/9 patients operated limbs 2012 January (18 limbs, 11/18 unclear limbs positive) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix II (online only). Continued

Outcomes ϩ Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Follow-Up level

Study period: 2007- 1/4 symptomatic NB–CTA considered Occluded artery in Muscle/band section only Follow-up duration: Selective outcome 2009 bilaterally superior in 13/13 3/13 (23%) 6/13 (46%), NS reporting: no limbs endarterectomy ϩ muscle/band section 3/13 (23%), bypass graft ϩ muscle/band section 2/13 (15%), angioplasty (not described further) ϩ muscle/band section 2/13 (15%) Mean age 30 (range, Provocation maneuvers: PSD/aneurysm in Loss to follow-up: Source of funding: 9-58) yrs, 7M:2F plantar flexion and 2/13 (15%) NS unclear dorsiflexion Presenting symptoms No relationship to duration Follow-up tests: NS Academic: no by limb: IC of symptoms 5/13 (38%), rest pain 1/13 (7%), cold foot/calf swelling 2/13 (15%), atypical pain 1/13 (7%), acute ischemia 1/ 13 (7%) Duration of SIGN level of symptoms: 4 h-12 evidence: 3 mos 3/13 (23%) of limbs asymptomatic (all operated) PVD risk factors in 3/9 patients ih tal et Sinha ABPI, Ankle-brachial pressure index; CTA, computed tomography angiogram; DSA, digital subtraction arteriography; IC, intermittent claudication; MRI, magnetic resonance imaging; NS, not specified or not stated; PAES, popliteal artery entrapment syndrome; PSD, poststenotic dilatation; PTA, percutaneous transluminal angioplasty; PVD, peripheral vascular disease; PVR, pulse volume recording; SIGN, Scottish Intercollegiate Guidelines Network. 262.e7 262.e8

Appendix III (online only). Included retrospective case-series on PAES with a focus on treatment ih tal et Sinha Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Rich (1979)31 9 patients, 14 limbs Excercise testing, Type I ϭ 43%, type II ϭ 7%, All operated (14/14) Outcomes measures NS (results Free from risk of bias? Doppler US, type III ϭ 14%, type IV ϭ described as “good to provocation Doppler 28%, type I ϩ III ϭ 7% excellent”) US and plethysmography (frequency of use NS) Single center (USA) 5/9 (55%) of patients diagnosed Arteriography used in 1 coexisting venous Posterior approach in 14/ Follow-up duration: NS Incomplete outcome with bilateral PAES 14 limbs (accuracy entrapment 14 (100%) data: unclear unclear) Study period: 1966- Mean age 41 (range, 21-59) yrs, Provocation biplanar 1 coexisting tibial nerve Vein bypass graft Loss to follow-up: unclear Selective outcome 1979 9M:0F arteriography used in branch entrapment 4/14 (29%), TEA ϩ reporting: no 8/14 limbs (accuracy vein patch 2/14 (14%), unclear) muscle/band section only 8/14 (57%) Presenting symptoms by limb: Unclear if all patients Whelan-Rich classification Muscle not reattached Follow-up tests: NS Source of funding: unclear assessed bilaterally unclear Presenting symptoms by patient: Provocation maneuvers: Occluded artery in Academic: yes IC 9/9 (100%) plantar flexion and 3/14 (21%) dorsiflexion Duration of symptoms NS PSD/aneurysm in SIGN level of 3/14 (21%) evidence: 3 No. of asymptomatic limbs unclear PVD risk factors NS Ferrero (1980)32 7 patients, 7 limbs Arteriography (not Type IV ϭ 57%, type VI ϭ All operated (7/7) Outcomes measures NS Free from risk of bias? described further) 14%, unclear ϭ 28% used in 7 limbs (7 limbs positive) Single center (Italy) 0% of patients diagnosed with Ferrero classification Surgical approach NS Follow-up duration: NS Incomplete outcome bilateral PAES data: unclear Study period: Mean age 38 (range, 19-52) yrs, Occluded artery in 6/7 (86%) Thrombectomy ϩ patch Loss to follow-up: NS Selective outcome unclear 7M:0F 1/7 (14%), vein reporting: no bypass/interposition graft ϩ muscle/band SURGERY VASCULAR OF JOURNAL section 5/7 (71%), muscle/band section only 1/7 (14%) Presenting symptoms by limb: IC Follow-up tests: NS Source of funding: 5/7 (71%), paresthesia unclear 1/7 (14%), incidental finding during SFA thrombectomy 1/7 (14%) Duration of symptoms NS Academic: yes PVD risk factors NS SIGN level of 2012 January evidence: 3 oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Collins (1989)33 12 patients, 20 limbs Post-treadmill test ABPI Type I ϭ 5%, type II ϭ 32%, Surgery 18/20 (90%), no Asymptomatic after surgery 8/ Free from risk of bias? used in 12/12 type III ϭ 26%, type IV ϭ surgery 2/20 (10%) 11 patients (73%), late vein patients (20/24 37% [patient refusal] graft/patch failure 2/4 (50%) limbs positive) [with ‘mild’ recurrent symptoms, unclear if reoperated], reoperation 1/ 11 patients (9%) [missed type IV lesion] Single center (USA) 8/12 (67%) of patients Bilateral biplanar Whelan-Rich classification Posterior approach in 18/ Outcome for asymptomatic Incomplete outcome diagnosed with bilateral PAES provocation 18 (100%) operated limbs unclear data: unclear arteriography used in 12/12 patients (20/ 24 limbs positive) Study period: 1977- 3/8 symptomatic bilaterally Provocation maneuvers: Occluded artery in SV bypass graft ϩ Follow-up duration: unclear Selective outcome 1988 plantar flexion and 4/20 (20%) muscle/band section (range, 1 month: ‘long- reporting: no dorsiflexion 2/18 (11%), TEA, vein term’) patch ϩ muscle/band section 2/18 (11%), muscle/band section only 14/18 (78%) Mean age 27 (range, 19-53) yrs, Relationship to duration of Muscle not reattached Loss to follow-up: unclear Source of funding: 10M:2F symptoms unclear unclear Presenting symptoms by limb: IC Follow-up tests: post-treadmill Academic: yes 14/20 (70%), IC ϩ acute test ABPI ischemia 1/20 (5%) Duration of symptoms: mean SIGN level of 13 (range, 2-36) mos evidence: 3 5/20 (25%) of limbs asymptomatic (no. operated unclear) PVD risk factors NS Gyftokostas No. of patients NS, 74 limbs Provocation ABPI used Some types described All operated (74/74) Outcomes measures NS (results Free from risk of bias? (1991)34 for all cases (accuracy anatomically but described as “excellent”) NS, “only useful for classification system NS patent vessels”) Single center Incidence of bilateral cases Bilateral provocation Occluded artery in Posterior approach in 74/ Follow-up duration: mean 96 Incomplete outcome (Greece) unclear arteriography used 23/74 (31%) 74 (100%) mos (no further details given) data: no for all patients (accuracy NS) Study period: 1974- Mean age 25 (range, 21-30) yrs, Provocation maneuvers: PSD/aneurysm in Muscle/band section 74/ Loss to follow-up: NS Selective outcome

1990 “all but 1 male” plantar flexion 10/74 (13.5%) 74 (100%), vein graft reporting: no al et Sinha number NS Presenting symptoms by limb or Muscle not reattached Follow-up tests: NS Source of funding: patient NS unclear Duration of symptoms NS Academic: no No. asymptomatic limbs unclear SIGN level of

evidence: 3 262.e9 PVD risk factors NS 262.e10 Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level ih tal et Sinha Zund (1995)35 20 patients, 26 limbs Provocation ABPI used Type I ϭ 71%, type II 29% Surgery 24/26 (92%), no Symptom relief after surgery Free from risk of bias? in 18/20 patients surgery 2/26 (8%) NS, endarterectomy failure (unclear if all patients [patient refusal] 11/11 (100%) [six assessed bilaterally, reoperated], interposition accuracy unclear) graft failure 8/12 (67%) [none reoperated] Single center 6/20 (30%) of patients Static arteriography Insua classification Surgical approach NS Outcome for asymptomatic Incomplete outcome (Switzerland) diagnosed with bilateral PAES used in 6/20 patients operated limbs unclear data: unclear (unclear if bilateral studies performed, accuracy unclear) Study period: 1967- Mean age 38.5 (range, 15-72) CT used in 20/20 PSD/aneurysm in 1/26 (4%) Muscle/band section 24/ Follow-up duration: mean Selective outcome 1993 yrs, 17M:3F patients (bilateral 24 (100%), 86 (range, 6-264) mos reporting: no assessment, 40 limbs, endarterectomy ϩ/Ϫ unclear if dynamic vein patch scan); accuracy NS 11/24 (46%), vein interposition graft 12/ 24 (50%), vein bypass graft 2/24 (8%), aneurysm resection ϩ vein patch 1/24 (4%), operative angioplasty 1/24 (4%) Presenting symptoms by limb or Provocation maneuvers: Relationship to duration of Loss to follow-up: unclear Source of funding: patient NS plantar flexion and symptoms unclear unclear dorsiflexion Duration of symptoms: mean 60 Follow-up tests: NS Academic: yes mos No. of asymptomatic limbs SIGN level of unclear evidence: 3 PVD risk factors NS Rosset (1995)36 11 patients, 15 limbs Provocation Types described anatomically All operated (15/15) Outcome measures: NS (results Free from risk of bias? arteriography in 11/ but classification system described as “excellent”) 11 patients (unclear if NS bilateral studies performed, 15 limbs

positive) SURGERY VASCULAR OF JOURNAL Single center 4/11 (36%) of patients Venography in 1/11 1 coexisting venous Posterior approach Follow-up duration: unclear Incomplete outcome (France) diagnosed with bilateral PAES patients entrapment (frequency unclear) data: unclear Study period: 1984- Mean age 28 (range, 19-48) yrs, CT used “3 times” Occluded artery in Medial approach Loss to follow-up 0% Selective outcome 1994 10M:1F (unclear if dynamic 2/15 (13%) (frequency unclear) reporting: no scan) Presenting symptoms by limbs: MRI used “4 times” Muscle/band section Follow-up tests: DUS Source of funding: unclear (unclear if dynamic only, 12/15 (80%), SV unclear scan) bypass graft 3/15 (20%) Presenting symptoms by patient: Provocation maneuvers: Academic: yes

IC 9/11 (82%), acute not described 2012 January ischemia 1/11 (9%), atypical pain 1/11 (9%) Duration of symptoms NS SIGN level of evidence: 3 oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

No. of asymptomatic limbs unclear PVD risk factors NS Porcellini (1997)37 9 patients, 11 limbs Provocation Doppler Types NS All operated (11/11) Asymptomatic after surgery 10/ Free from risk of bias? US (PST) (frequency 11 limbs (91%), late vein of use unclear, 6 graft failure 1/5 (20%) [not limbs positive) reoperated] Single center (Italy) 2/9 (22%) of patients diagnosed Treadmill test Classification system not Posterior approach in 11/ Follow-up duration: mean Incomplete outcome with bilateral PAES (frequency of use specified 11 (100%) 54 (range, 7-93) mos data: unclear unclear, 6 limbs positive) Study period: 1983- 2/2 symptomatic bilaterally Provocation DUS Occluded artery in Vein bypass/interposition Loss to follow-up: unclear Selective outcome 1995 (frequency of use 4/11 (36%) graft ϩ muscle/band reporting: unclear unclear) section 5/11 (45%), muscle/band section only 6/11 (55%) Mean age 23 (range, 16-58) yrs, CTA used in 4/9 Aneurysm in 1/11 (9%) Muscle not reattached Follow-up tests: ABPI Source of funding: 9M:0F patients (unclear if unclear dynamic scan) Presenting symptoms by limb: IC MRI used in 2/9 Relationship to duration of Academic: yes 3/11 (27%), cold/numb foot patients (unclear if symptoms unclear after exercise 5/11 (45%), dynamic scan) acute ischemia 2/11 (18%), painful popliteal artery aneurysm 1/9 (9%) Duration of symptoms: 3 days Provocation SIGN level of Ϫ48 mos arteriography used in evidence: 3 9/9 patients (unclear if bilateral studies performed, 11 limbs positive) PVD risk factors in 0/9 patients Unclear if all patients assessed bilaterally Provocation maneuvers: plantar flexion and dorsiflexion Hoelting (1997)38 19 patients, 23 limbs Provocation ABPI used Type I ϭ 22%, type II ϭ All operated (23/23) Asymptomatic after surgery 16/ Free from risk of bias? in 19/19 patients 26%, type III ϭ 52% 23 limbs (70%), early vein (accuracy unclear) graft failure 2/18 (11%) [1/2 required thrombectomy, 1/2 required thrombolysis], 1/ al et Sinha 23 (4%) hematoma [required reoperation], late vein graft failure 2/18 (11%) [causing critical ischemia, both reoperated], amputation 1/ 23 (4%) (“minor”, level not 262.e11 specified) 262.e12

Appendix III (online only). Continued

Risk of bias/SIGN ih tal et Sinha Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Single center 4/19 (21%) of patients Biplanar provocation Heidelberg classification Posterior approach Outcome for asymptomatic Incomplete outcome (Germany) diagnosed with bilateral PAES arteriography used in (frequency NS) operated limbs unclear data: unclear 19/19 patients (unclear if bilateral studies performed, accuracy unclear) Study period: 1976- Median age 43 (range, 19-61) Provocation maneuvers: Occluded artery in Medial approach Follow-up duration: mean Selective outcome 1995 yrs, 19M:0F knee extension, foot 19/23 (83%) (frequency NS) 114 (range, 6-240) mos reporting: no plantar flexion and dorsiflexion Presenting symptoms by limb: TEA ϩ muscle/band Loss to follow-up: unclear Source of funding: NS section 1/23 (4%), unclear TEA, vein patch ϩ muscle/band section 6/23 (26%), vein interposition graft ϩ muscle/band section 12/23 (52%), muscle/ band section only 4/ 23 (17%) Presenting symptoms by patient: Follow-up tests: ABPI Academic: no IC 19/19 (100%) Duration of symptoms not SIGN level of specified evidence: 3 No. of asymptomatic limbs unclear PVD risk factors in 0/19 patients Di Marzo (1997)39 30 patients (1 bilateral redo Provocation Doppler Type II ϭ 42%, type III ϭ All operated (45/45) Asymptomatic after surgery 34/ Free from risk of bias? case), 45 limbs US used in 30/30 31%, type VI ϭ 27% 45 (76%), early vein graft patients (positive in failure 3/15 (20%) [2/3 all patients) reoperated], 5/45 (11%) wound infection, 1/45 (2%) popliteal artery thrombosis, 2/45 (4%) recurrence of symptoms requiring reoperation, late vein graft SURGERY VASCULAR OF JOURNAL failure 2/15 (13%) [unclear if reoperated] Single center (Italy) 13/30 (43%) of patients Provocation DUS used 9 coexisting venous Posterior approach Follow-up duration - mean 95 Incomplete outcome diagnosed with bilateral PAES in 30/30 patients entrapments (frequency NS) mos (range, 11-198) data: yes (positive in all patients) Study period: 1979- 13/13 symptomatic bilaterally Provocation Di Marzo classification Medial approach Loss to follow-up Ϫ0% Selective outcome 1995 arteriography used in (frequency NS) reporting: unclear 30/30 patients (unclear if bilateral 2012 January studies performed, 43 limbs positive) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Mean age 35 (range, 14-62) yrs, Venography used in 2 Occluded artery in Muscle/band section only Follow-up tests: ABPI, DUS, Source of funding: 23M:7F limbs 6/45 (13%) 28/45 (62%), balloon treadmill testing unclear angioplasty ϩ muscle/ band section 2/45 (4%), PTFE graft ϩ muscle/band section 1/45 (2%), vein bypass/interposition graft ϩ muscle/band section 14/45 (31%) Presenting symptoms by limb: IC Provocation maneuvers: PSD/aneurysm in Muscle not reattached Academic: no 23/45 (51%), cold/numb/ plantar flexion 6/45 (13%) painful foot after exercise 21/ 45 (47%), tissue loss 1/45 (2%) Duration of symptoms: mean Relationship to duration of SIGN level of 22 Ϯ 2 mos symptoms unclear evidence: 3 PVD risk factors not specified Deshpande (1998)40 8 patients (1 redo case), 16 limbs Provocation DUS used Type I ϭ 12.5%, functional ϭ All operated (16/16) Asymptomatic after surgery 12/ Free from risk of bias? in 8/8 patients (16 87.5% (“tethering by 16 limbs (75%) [first surgery limbs positive) bands” classed as in re-do case classed as functional PAES by successful by authors], 4/16 authors) recurrent symptoms [2/4 reoperated, 2/4 unclear if reoperated] Single center 8/8 (100%) of patients Bilateral biplanar Classification system NS Medial approach in 14/ No new symptoms in 1/1 Incomplete outcome (Australia) diagnosed with bilateral PAES provocation 16 (87.5%) asymptomatic operated limbs data: yes arteriography used in 8/8 patients (16/16 limbs positive) Study period: 1993- 7/8 symptomatic bilaterally Provocation maneuvers: Occluded artery in 1/16 (6%) Medial ϩ posterior Follow-up duration: “minimum Selective outcome 1996 knee extension, foot approach in 1 year” (no further details reporting: no plantar flexion 2/16 (12.5%) [redo given) case] Mean age 22.5 (range, 18-26) Relationship to duration of Muscle/band section only Loss to follow-up 0% Source of funding: yrs, 3M:5F symptoms unclear 15/16 (94%), SV unclear bypass graft ϩ muscle/ band section 1/16 (6%) Presenting symptoms by limb: IC Muscle not reattached Follow-up tests: DUS and Academic: yes 15/16 (94%) arteriography Duration of symptoms unclear SIGN level of al et Sinha evidence: 3 5/8 previously misdiagnosed as CPCS and treated with fasciotomies 1/16 (6%) of limbs asymptomatic (operated) 262.e13 PVD risk factors NS 262.e14 Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level ih tal et Sinha Lambert (1998)41 17 patients, 21 limbs Plain radiography used Types NS 2/17 (12%) patients had Asymptomatic after surgery 12/ Free from risk of bias? in 1/21 limbs initial thrombolysis 17 limbs (70%), (unsuccessful) interposition/bypass graft failure 2/6 (33%) [both reoperated], amputation (0%), reoperation rate for recurrent symptoms unclear 10 centers (UK) 4/17 (23%) of patients DUS used in 4/21 Classification system NS Surgery 17/21 (81%), no Outcome for asymptomatic Incomplete outcome diagnosed with bilateral PAES limbs surgery 4/21 (19%) operated limbs unclear data: no [1/4 patient refusal, other cases reason unclear] Study period: 1984- 1/4 symptomatic bilaterally MRI used in 1/21 Surgical approach NS Outcome for asymptomatic Selective outcome 1995 limbs nonoperated limbs unclear reporting: no Median age 29 (range, 14-45) Arteriography (not Muscle/band section only Outcome for symptomatic Source of funding: yrs, 15M:2F described further) 4/17 (23.5%), TEA, nonoperated limbs unclear unclear used in 20/21 limbs vein patch ϩ muscle/ band section 4/17 (23.5%), TEA ϩ excision of bony exostosis 1/17 (6%), vein patch ϩ muscle/ band section 2/17 (12%), interposition graft (type NS) 2/17 (12%), bypass graft (type NS) 4/17 (23.5%) Presenting symptoms by limb: IC Unclear if all patients Follow-up duration: NS Academic: no 17/21 (81%), acute ischemia assessed bilaterally 1/21 (5%) Duration of symptoms NS Loss to follow-up: unclear SIGN level of evidence: 3 3/21 (14%) of limbs Follow-up tests: NS asymptomatic (number operated unclear)

PVD risk factors NS SURGERY VASCULAR OF JOURNAL Davidovich (1999)42 8 patients, 9 limbs Bilateral provocation Type I ϭ 11%, type II ϭ All operated (9/9) Asymptomatic after surgery 8/9 Free from risk of bias? ABPI used in 8/8 22%, type III ϭ 44%, type limbs (89%), early graft patients (12/16 IV ϭ 11%, not classified ϭ failure (0%), late occlusion limbs positive) 11% 1/9 (11%) [thrombectomy case, not reoperated], amputation (0%) Single center 1/8 (12.5%) of patients Provocation Delaney classification Posterior approach in 8/9 No new symptoms in 1/1 Incomplete outcome (Yugoslavia) diagnosed with bilateral PAES arteriography used in 89%) asymptomatic operated limbs data: no 8/8 patients (10

limbs studied, 9/10 2012 January positive) Study period: 1985- 0/1 symptomatic bilaterally Provocation maneuvers: Occluded artery in 7/9 (78%) Medial approach in 1/ Follow-up duration: mean Selective outcome 1996 plantar flexion and 9 (11%) 75 (range, 12-144) mos reporting: no dorsiflexion oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Mean age 34.6 (range, 25-54) PSD/aneurysm in 1/9 (11%) Muscle/band section only Loss to follow-up 0% Source of funding: yrs, 7M:1F 1/9 (11%), unclear thrombectomy ϩ muscle/band section 1/9 (11%), vein interposition graft ϩ muscle/band section 5/9 (55%), vein interposition graft only 1/9 (11%), vein bypass graft 1/9 (11%) Presenting symptoms by limb: Follow-up tests: ABPI Academic: yes acute ischemia 6/9 67%), chronic ischemia 2/9 (22%) Duration of symptoms NS SIGN level of evidence: 3 1/9 (11%) of limbs asymptomatic (operated) PVD risk factors in 0/8 patients Levien (1999)43 48 patients, 88 limbs Provocation ABPI Type I ϭ 5%, type II ϭ 14%, Surgery 82/88 (93%), no Symptom relief after surgery Free from risk of bias? (frequency of use and type III ϭ 37.5%, type IV surgery 6/88 (7%) [4/ unclear, late occlusion 1/ accuracy unclear) ϭ 9%, functional ϭ 34% 6 functional 16 (6%) [thrombectomy case, entrapment, 2/6 reoperated], amputation delayed presentation] [level NS ] 1/82 (1%) Single center (South 40/48 (83%) of patients Provocation DUS 10 coexisting venous Posterior approach in 8/ Outcome for 5/6 symptomatic Incomplete outcome Africa) diagnosed with bilateral PAES (frequency of use and entrapments 82 (10%) nonoperated limbs [four data: unclear accuracy unclear) functional entrapments, one anatomical entrapment] stated Study period: 1987- 40/40 symptomatic bilaterally Provocation Whelan/modified Rich Medial approach in 74/ Follow-up duration: median Selective outcome 1997 arteriography classification 82 (90%) 48 (range, 12-120) mos reporting: no (frequency of use unclear, 70/88 limbs positive) Mean age 34.9 (range, 16-55) Unclear if all patients Occluded artery in Muscle/band section only Loss to follow-up 0% Source of funding: yrs, 60% male assessed bilaterally 18/88 (20%) 66/82 (80%), unclear thrombectomy, vein patch ϩ muscle/band section 1/82 (1%), vein bypass graft ϩ muscle/ band section 15/82 (18%) al et Sinha Presenting symptoms by limb: IC Provocation maneuvers: PSD/aneurysm in 8/88 (9%) Follow-up tests: DUS Academic: no 70/88 (80%), critical ischemia plantar flexion and 18/88 (20%) dorsiflexion Duration of symptoms NS SIGN level of evidence: 3 No. of asymptomatic limbs 262.e15 unclear PVD risk factors NS 262.e16 Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level ih tal et Sinha Ring Jr (1999)44 8 patients, 16 limbs Bilateral biplanar Type I ϭ 6%, type II ϭ 25%, 3/8 (37.5%) of patients Symptom relief after surgery Free from risk of bias? provocation type III ϭ 6%, type IV ϭ had initial thrombolysis NS, amputation (0%), arteriography used in 31%, type V ϭ 6%, (all required surgery) reoperation rate for vein 8/8 patients (16/16 functional ϭ 12.5% grafts (0%) limbs positive) Single center (USA) 8/8 (100%) of patients Provocation maneuvers: 1 coexisting venous Surgery 13/16 (81%), no Outcome for asymptomatic Incomplete outcome diagnosed with bilateral PAES plantar flexion and entrapment surgery 3/16 (19%) operated limbs unclear data: no dorsiflexion [2/3 patient refusal, 1/3 reason unclear] Study period: 1991- 3/8 symptomatic bilaterally Whelan-Rich classification Surgical approach NS Follow-up duration: NS Selective outcome 1998 reporting: no Mean age 33.7 (range, 24-56) Occluded artery in 2/16 Muscle/band section only Loss to follow-up 12.5% (prior Source of funding: yrs, 8M:0F 12.5%) 8/13 (61.5%), to surgery) unclear thrombectomy ϩ muscle/band section 1/13 (8%), vein interposition/bypass graft 3/13 (23%), fasciotomy 1/13 (8%) [functional entrapment] Symptoms by limb: IC PSD/aneurysm in Follow-up tests: NS Academic: yes 10/16 (62.5%), numb foot 2/16 (12.5%) after exercise 1/16 (6%) Duration of symptoms: 2 days– Relationship to duration of SIGN level of 84 mos symptoms unclear evidence: 3 5/16 (31%) of limbs asymptomatic (all operated) PVD risk factors in 5/8 patients Andrikopoulos 14 patients, 18 limbs Provocation Doppler Some types described All operated (18/18) Asymptomatic after surgery 14/ Free from risk of bias? (1999)45 and DUS used in anatomically but 18 limbs (78%), early vein 18/18 limbs (unclear classification system NS graft failure 1/7 (14%) if all patients assessed [reoperated], late vein graft bilaterally, 9 imbs failure 2/7 (28%) [not positive) reoperated], early PTFE graft failure 1/4 (25%), late PTFE

graft failure 1/4 (25%) [not SURGERY VASCULAR OF JOURNAL reoperated], above-knee amputation 1/18 (5%) [early PTFE graft failure], DVT 2/18 (11%) Single center 4/14 (29%) of patients Bilateral biplanar 2 coexisting venous Posterior approach in 17/ No new symptoms in 4/4 Incomplete outcome (Greece) diagnosed with bilateral PAES provocation entrapments 18 (94%) asymptomatic operated limbs data: no arteriography used in 13/14 patients (18/ 26 limbs positive)

Study period: 1986- 0/4 symptomatic bilaterally MRI used for post-op Occluded artery in Medial approach in 1/ Follow-up duration: median Selective outcome 2012 January 1996 diagnosis in one 4/18 (22%) 18 (6%) (misdiagnosed 24 (range, 5-96) mos reporting: no patient initially as embolic misdiagnosed as phenomenon) embolic phenomenon Appendix III (online only). Continued 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Mean age 32 (range, 16-54) yrs; CT (frequency of use PSD/aneurysm in Vein graft ϩ muscle/band Loss to follow-up 2/14 (14%) Source of funding: 13M:1F NS, unclear if 2/18 (11%) section 7/18 (39%), after 3 yrs unclear dynamic scan) PTFE graft ϩ muscle/ band section 2/18 (11%), TEA, PTFE patch ϩ muscle/ band section 1/18 (5%), muscle/ band section only 7/ 18 (39%), PTFE graft only 1/18 (11%) [misdiagnosed case] Presenting symptoms by limb: IC Provocation maneuvers: Follow-up tests: unclear Academic: yes 7/18 (39%), acute ischemia plantar flexion and 2/18 (11%), atypical pain 3/ dorsiflexion 18 (17%), rest pain 1/18 (5%), rest pain and tissue loss 1/18 (5%) Duration of symptoms NS SIGN level of evidence: 3 4/18 (22%) of limbs asymptomatic (all operated) PVD risk factors in 4/14 patients Ohara (2001)46 10 patients, 11 limbs Provocation Doppler Type I ϭ 18%, type II ϭ All operated (11/11) Asymptomatic after surgery 10/ Free from risk of bias? US (PST) used in 64%, type III 36%, type IV 11 limbs (91%), late vein 5/10 patients (not ϭ 0% patch failure 1/3 (33%) [not used if artery reoperated] occluded) Single center (Japan) 1/10 (10%) of patients Static (nonprovocation) Delaney classification Posterior approach in 11/ Follow-up duration: median Incomplete outcome diagnosed with bilateral PAES arteriography used in 11 (100%) 149 (range, 38-223) mos data: yes 10/10 patients (unclear if bilateral studies performed, 11 limbs positive) Study period: 1980- 1/1 symptomatic bilaterally CT used in 10/10 Occluded artery in TEA, vein patch ϩ Loss to follow-up 0% Selective outcome 1999 patients (“all showed 5/11 (45%) muscle/band section reporting: no positive findings”, 2/11 (18%), vein patch unclear if dynamic ϩ muscle/band section scan) 1/11 (9%), vein interposition/bypass graft ϩ muscle/band section 7/11 (63%), ih tal et Sinha muscle/band section only 1/11 (9%) Median age 34.7 (range, 16-67) Unclear if all patients PSD/aneurysm in Muscle not reattached Follow-up tests: DUS Source of funding: yrs, 10M:0F assessed bilaterally 4/11 (36%) unclear Presenting symptoms by limb: IC Provocation maneuvers: Academic: yes 9/11 (82%), cold foot after plantar flexion and 262.e17 exercise 2/11 (18%) dorsiflexion Duration of symptoms NS SIGN level of evidence: 3 PVD risk factors in 5/10 patients 262.e18

Appendix III (online only). Continued

Risk of bias/SIGN ih tal et Sinha Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Ruppert (2004)47 23 patients, 32 limbs Provocation ABPI used Most types NS or described All operated (32/32) Outcome measures: NS Free from risk of bias? in 32/32 limbs (30 “anatomical”, 2 (accuracy NS) “functional”) Single center 9/23 (39%) of patients Provocation Classification system not used Surgical approach NS Outcome for asymptomatic Incomplete outcome (Germany) diagnosed with bilateral PAES arteriography used in operated limbs unclear data: unclear 32/32 limbs (accuracy unclear) Study period: 1986- Mean age 38.3 (range, NS) yrs, Unclear if all patients Occluded artery in Muscle/band section only Follow-up duration: unclear Selective outcome 2000 19M:4F assessed bilaterally 8/32 (25%) 22/32 (69%), reporting: no thrombectomy ϩ muscle/band section 1/32 (3%), thrombectomy, vein patch ϩ muscle/band section 3/32 (9%), vein interposition graft ϩ muscle/band section 5/32 (16%), vein bypass graft ϩ muscle/ band section 1/32 (9%) Presenting symptoms by limb NS Provocation maneuvers: Loss to follow-up: unclear Source of funding: knee extension, foot unclear plantar flexion and dorsiflexion Presenting symptoms by patient Follow-up tests: provocation Academic: yes NS ABPI, DUS, arteriography Duration of symptoms NS SIGN level of evidence: 3 No. of asymptomatic limbs Comment: purpose of unclear study was to assess effectiveness of post-op ABPI in assessing success of surgery for PAES PVD risk factors NS Goh (2005)48 6 patients, 8 limbs Bilateral provocation Type III ϭ 100% All operated (8/8) Asymptomatic after surgery 7/8 Free from risk of bias? SURGERY VASCULAR OF JOURNAL Doppler US (PST) limbs (87.5%), early graft used in 1/6 patients failure 1/4 (25%), (1/2 limbs positive) amputation [level NS] 1/ 8 (12.5%) [after graft failure] Single center 2/6 (33%) of patients diagnosed Bilateral provocation Delaney classification Posterior approach in 5/ “No post-op complications” Incomplete outcome (Singapore) with bilateral PAES DUS used in 4/6 8 (62.5%) data: yes patients (5/8 limbs positive) Study period: 1995- 2/2 symptomatic bilaterally Bilateral provocation Occluded artery in Medial approach in 3/ Follow-up duration: median Selective outcome 2004 CTA used in 3/6 3/8 (37.5%) 8 (37.5%) 15 (range, 1-108) mos reporting: unclear 2012 January patients (5/6 limbs positive) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Mean age 34 (range, 27-38) yrs, Bilateral provocation No relationship to duration SV bypass graft ϩ Loss to follow-up: unclear Source of funding: 5M:1F MRI used in 1/6 of symptoms muscle/band section unclear patients (0/2 limbs 2/8 (25%), TEA, vein positive) patch ϩ muscle/band section 1/8 (12.5%), vein patch ϩ muscle/ band section 1/8 (12.5%), muscle/ band section only 4/ 8 (50%) Presenting symptoms by limb: IC Bilateral provocation Follow-up tests: DUS Academic: yes 7/8 (87.5%), rest pain ϩ arteriography used in critical ischemia 1/8 (12.5%) 3/6 patients (3/6 limbs positive) Duration of symptoms: 2 days- Provocation maneuvers: SIGN level of 48 mos plantar flexion evidence: 3 PVD risk factors in 2/6 patients Bustabad (2006)49 8 patients, 12 limbs Provocation ABPI used Type II ϭ 58%, type III ϭ 1/8 (12.5%) of patients Asymptomatic after surgery 7/ Free from risk of bias? in 8/8 patients 8%, type V ϭ 8%, treated with 10 limbs (70%), early vein (unclear if patients functional ϭ 25% thrombolysis prior to graft failure 1/10 (10%) assessed bilaterally) surgery (bypass graft) [required graft thrombectomy], late vein graft failure 2/10 (20%) [not reoperated], amputation (0%) Single center (Spain) 4/8 (50%) of patients diagnosed Provocation DUS used Whelan-Rich classification Surgery 10/12 (83%), no Recurrent symptoms in Incomplete outcome with bilateral PAES in 8/8 patients surgery 2/12 (16%) 2/3 (66%) of functional data: unclear (unclear if patients [1/2 due to patient entrapments (after graft assessed bilaterally, refusal, other case failure, not reoperated) “not useful with reason unclear] occluded artery”) Study period: 1998- 2/4 symptomatic bilaterally MRI/MRA used in 7/8 Occluded artery in Posterior approach in 6/ Resolution of symptoms in 1/ Selective outcome 2005 patients (arteries 6/12 (50%) 10 (60%) 2 (50%) of symptomatic reporting: no assessed bilaterally, nonoperated limbs (both type unclear if dynamic II) scan, accuracy unclear) Mean age 38 (range, 24-63) yrs, DSA (unclear if done Occlusion ϩ PSD/aneurysm Medial approach in 4/ Outcome for asymptomatic Source of funding: 6M:2F with provocation in 2/12 (16%) 10 (40%) operated limbs unclear unclear maneuvers, frequency of use NS) Presenting symptoms by limb: IC Provocation maneuvers: ‘Focal injury’ in 4/12 (33%) Vein bypass graft ϩ Follow-up duration: mean Academic: yes

6/12 (50%), acute ischemia plantar flexion and muscle/band section 43 (range, 12-96) mos al et Sinha 3/12 (25%), incidental finding dorsiflexion 9/10 (90%), popliteal during surgery for popliteal angioplasty, vein patch ϩ artery aneurysm 1/12 (8%) muscle/band section 1/10 (10%) Duration of symptoms NS Muscle reattachment only Loss to follow-up: unclear SIGN level of

in type II evidence: 3 262.e19 2/12 (16%) of limbs Follow-up tests: Doppler and asymptomatic (both operated) DUS PVD risk factors in 3/8 patients 262.e20 Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level ih tal et Sinha

Gourgiotis (2008)50 38 patients, 49 limbs Bilateral provocation Type I ϭ 18.4%, type II ϭ All operated (49/49) Asymptomatic after surgery 49/ Free from risk of bias? Doppler US (PST) 67.3%, type III ϭ 14.3% 49 limbs (100%), graft failure used in 38/38 0/49 (0%), wound infection patients (41/76 or hematoma 8/38 patients limbs positive) (21%) [managed conservatively] Single center 11/38 (29%) of patients DUS used in 43 limbs Delaney classification Posterior approach Follow-up duration: median Incomplete outcome (Greece) diagnosed with bilateral PAES (criteria for use (frequency NS) 34 (8-42) mos data: yes unclear, 32/43 limbs positive) Study period: 1995- 11/11 symptomatic bilaterally CT used in 38/38 Occluded artery in 4/49 (8%) Medial approach Loss to follow-up 0% Selective outcome 2002 patients (unclear if (frequency NS) reporting: no dynamic scan, accuracy unclear) Mean age 21 (range, 18-29) yrs, CTA (frequency of use PSD/aneurysm in Muscle/band section 33/ Follow-up tests: DUS Source of funding: 31M:7F NS) 17/49 (35%) 49 (67%), TEA, vein unclear patch ϩ muscle/band section in 5/49 (10%), SV bypass/interposition graft ϩ muscle/band section in 11/49 (22.5%) Presenting symptoms by limb: IC Arteriography (not Relationship to duration of Muscle not reattached Academic: unclear 43/49 (88%), cold foot after described further) symptoms unclear exercise 6/49 (12%) positive in 49 limbs (number of limbs screened unclear) Duration of symptoms: 8-24 mos Provocation maneuvers: SIGN level of plantar flexion evidence PVD risk factors in 27/38 3 patients Turnipseed (2009)51 57 patients, No. of limbs unclear Provocation ABPI (used Anatomic entrapment 14/ All operated (57/57) Symptom relief after surgery Free from risk of bias? for all patients, 57 57 (24.5%), functional unclear, 0% reoperation rate limbs positive) entrapment for functional entrapment 43/57 (75.5%) surgery during “extended” follow-up; wound infection SURGERY VASCULAR OF JOURNAL 2%, seroma 4.6% Single center (USA) Incidence of bilateral cases Provocation PVR (used Anatomic descriptions NS Medial approach in at Outcome for asymptomatic Incomplete outcome unclear for all patients, 57 least 43/57 (75.5%) operated limbs unclear data: unclear limbs positive) (all functional entrapments) Study period: 1987- Mean age 36 (range, 22-71) yrs, Provocation DUS Classification system NS Posterior approach Follow-up duration: unclear Selective outcome 2007 20M:37F (frequency of use (frequency unclear) reporting: no unclear) Presenting symptoms by limb: IC Provocation Muscle/band section for Loss to follow-up: unclear Source of funding: 50/57 (88%), paresthesia 19/ MRA/MRI at least 43/57 (75.5%), unclear 2012 January 57 (33%), digital ischemia 6/ (frequency of use all functional 57 (10.5%), calf swelling 5/ unclear, 57 limbs entrapments 57 (9%) positive) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix III (online only). Continued

Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention Outcomes ϩ follow-up level

Duration of symptoms unclear Provocation Surgical procedures for Follow-up tests: provocation Academic: no arteriography anatomic entrapments ABPI/PVR (frequency of use NS unclear) No. of asymptomatic limbs Unclear if all patients SIGN level of unclear assessed bilaterally evidence: 3 PVD risk factors NS Provocation maneuvers: Comment: purpose of plantar flexion study was to describe diagnosis and treatment of functional PAES and chronic recurrent exertional compartment syndrome

ABPI, Ankle-brachial pressure index; CPCS, chronic posterior compartment syndrome; CTA, computed tomography angiogram; DSA, digital subtraction arteriography; DUS, duplex ultrasound; IC, intermittent claudication; MRA, magnetic resonance angiogram; MRI, magnetic resonance imaging; NS, not stated or not specified; PAES, popliteal artery entrapment syndrome; PSD, poststenotic dilatation; PST, positional stress test; PTFE, polytetrafluoroethylene PVR, pulse volume recording; SIGN, Scottish Intercollegiate Guidelines Network; PVD, peripheral vascular disease; TEA, thromboendarterectomy; US, ultrasound. ih tal et Sinha 262.e21 262.e22

Appendix IV (online only). Included retrospective case-series on popliteal vein entrapment syndrome (PVES)

Outcomes and Risk of bias/SIGN ih tal et Sinha Reference Patient characteristics Diagnostic adjuncts Description of pathology Intervention follow-up level

Raju (2000)52 30 patients, No. of Arm/foot pressure Abnormal insertion or origin Criteria for surgery: Complete relief of Free from risk of bias? limbs unclear differential used in all of gastrocnemius muscle “severe disabling pain after surgery 30 patients (accuracy 24/30 symptoms after failed 14/29 (48%), unclear) compression treatment complete relief of with popliteal swelling after entrapment observed surgery on venography” 12/29 (41%), healing of stasis ulcer/dermatitis 9/11 (82%) Single center (USA) 34% of patients Air plethysmography Entrapment by soleal sling Operated cases by limb Popliteal vein Incomplete outcome diagnosed with used in all 30 patients 3/30 unclear thrombosis 1/ data: no bilateral PVES (accuracy unclear) 30 (3%) Study period: 1996- Median age 49 (range, DUS used in all 30 Perivenous fibrosis 13/30 Operated cases by patient: Follow-up duration: Selective outcome 1998 27-73) yrs, 14M: patients (accuracy 30/30 (100%) median reporting: no 16F unclear) 14 (range, 2-36) mos Presenting symptoms Provocation ascending Aberrant course of vessels Medial approach in 30/ Loss to follow-up: Source of funding: by limb: unclear venography used in 2/30 30 (100%) 1/30 (3%) unclear all 30 patients (unclear if all patients assessed bilaterally, number of positive results unclear) Presenting symptoms Popliteal vein pressure Unknown 1/30 Muscle/band/fascia Follow-up tests: Academic: yes by patient: swelling transduction in 9/30 section (frequency unclear (87%), pain (83%), patients (accuracy unclear), popliteal valve hyperpigmentation unclear) repair (74%), stasis (transcommissural ulceration (30%), valvuloplasty or axillary stasis dermatitis vein transfer) (7%), recurrent 11/30 (37%) cellulitis (13%) Duration of symptoms Toe plethysmography 8/30 coexisting arterial SIGN level of NS to assess arterial entrapments evidence: 3 entrapment SURGERY VASCULAR OF JOURNAL (frequency of use and accuracy unclear) No. of asymptomatic Provocation maneuvers: Vein sclerosis 13/30 limbs unclear plantar flexion Pre/poststenotic dilatation 5/30 Post-thrombotic changes 2/30 Hirokawa 200253 11 patients, 14 limbs Provocation Doppler Hypertrophy/abnormal head Criteria for surgery: those Asymptomatic after Free from risk of bias? and DUS (frequency of gastrocnemius muscle with positive surgery 2012 January of use unclear, 14/14 venography and CT 8/14 (57%) accuracy NS) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix IV (online only). Continued

Outcomes and Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Description of pathology Intervention follow-up level

Single center (Japan) 3/11 (27%) of patients Provocation ascending Entrapment by plantaris All operated (14/14) “No complications Incomplete outcome diagnosed with venography muscle 1/14 occurred” data: yes bilateral PVES (frequency of use unclear, accuracy NS) Study period: 1984- Mean age 27.6 (range, CT (frequency of use Prestenotic dilatation 1/14 Posterior approach in 14/ “No re-operations Selective outcome 2001 NS) yrs, 0M:11F unclear, accuracy NS) 14 (100%) performed” reporting: yes Presenting symptoms Unclear if all patients Muscle/band section 14/ Follow-up duration: Source of funding: by limb: unclear assessed bilaterally 14 (100%), Dacron 36-120 mos unclear reinforcement of popliteal vein 1/14 (7%) Presenting symptoms Provocation maneuvers: Loss to follow-up: Academic: no by patient: calf dorsiflexion unclear ache/swelling (frequency NS) Duration of symptoms Follow-up tests: SIGN level of NS unclear evidence No. of asymptomatic 3 limbs unclear Milleret (2007)54 11 patients, 11 limbs Provocation Doppler Hypertrophy or abnormal Criteria for surgery: Symptom Free from risk of bias? and DUS (frequency insertion of gastrocnemius unclear “improvement” of use NS, accuracy muscle 11/11 after surgery 9/ unclear) 11 (82%) (SF-12 QOL used for 5/11 patients) Single center 0% of patients Biplanar provocation Hypertrophy of plantaris/ All operated (11/11) Repeat surgery Incomplete outcome (France) diagnosed with venography popliteus muscle 4/11 (aponeurectomy) data: unclear bilateral PVES (frequency of use NS, 2/11 (18%) accuracy unclear) Study period: 2001- Mean age 28 (range, Provocation maneuvers: Perivenous fibrosis 7/11 Posterior approach in 8/ Sural vein Selective outcome 2006 19-47) yrs, 3M: plantar flexion and 11 (73%) thrombosis 1/ reporting: no 11F dorsiflexion 11 (9%) Presenting symptoms Fibrous band 6/11 Medial approach in 3/ Follow-up duration: Source of funding: by limb: exertional 11 (27%) unclear unclear calf swelling 3/11 (27%), positional calf swelling 2/11 (18%), recurrent varicose

veins 4/11 (36%), al et Sinha sural vein thrombosis 2/11 (18%) Duration of symptoms Muscle/band section ϩ Loss to follow-up: Academic: yes NS aponeurectomy 11/ unclear

11 (100%) 262.e23 Follow-up tests: SIGN level of unclear evidence: 3 262.e24 ih tal et Sinha Appendix IV (online only). Continued

Outcomes and Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Description of pathology Intervention follow-up level

Lane (2009)55 No. of patients Bilateral provocation Muscular/fibrous band 2/49 Criteria for surgery: Outcome measures: Free from risk of bias? unclear, 49 limbs DUS (frequency of “failed conservative improvement in use unclear, accuracy treatment with venous disease unclear) objective evidence of clinical score popliteal vein (3.9 Ϯ 1.2 to compression” 1.7 Ϯ 1.7, P Ͻ .001), improvement in provocation DUS detected vein diameter (1.0 Ϯ 2.1 to 9.0 Ϯ 1.5, P Ͻ .001) No. of centers Incidence of bilateral Provocation venography Hypertrophied Surgery 30/49, no Wound infection Incomplete outcome unclear (Australia) cases unclear (not further soleus/gastrocnemius surgery 19/49 [reasons 2/49 (4%) data: unclear described) used in muscles in “most” cases unclear] 2/49 limbs Study period: Mean age 43.6 (range, Provocation maneuvers: Posterior approach in 30/ Follow-up duration: Selective outcome unclear NS) yrs, M/F NS knee extension 30 (100%) mean 16.2 mos reporting: unclear Presenting symptoms Muscle/band section ϩ Loss to follow-up: Source of funding: by limb or patient: popliteal fossa 0% unclear unclear decompression 2/30 (7%), popliteal fossa decompression only 28/30 (93%) Duration of symptoms Follow-up tests: Academic: yes NS DUS No. of asymptomatic SIGN level of limbs unclear evidence: 3

Comment: study SURGERY VASCULAR OF JOURNAL cohort comprised obese patients (mean BMI 34.6 Ϯ 6.2 with a diagnosis of chronic venous hypertension)

BMI, Body mass index, kg/m2; CT, computed tomography; NS, not stated or not specified; QOL, quality of life; SF-12, Short Form 12; SIGN, Scottish Intercollegiate Guidelines Network; US, ultrasound. aur 2012 January oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL

Appendix V (online only). Included retrospective case series on nerve entrapments in the popliteal fossa

Outcomes and Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention follow-Up level

Mastaglia (2000)56 9 patients, 9 limbs Motor nerve Entrapment by soleal arch Criteria for surgery: Symptom Free from risk of bias? conduction studies 6/6 “severe pain and “improvement” used in 9/9 limbs (2 disability” after surgery 6/ limbs positive) 6 (100%) (not quantified) Single center 0% of patients Sensory nerve 3 coexisting venous Surgery 6/9 (67%), no Symptom Incomplete outcome (Australia) diagnosed with conduction studies abnormalities (1/3 venous surgery 3/9 (33%) “improvement” in data: yes bilateral nerve used in 4/9 limbs (1 entrapment, 1/3 venous nonoperated cases entrapment limb positive) thrombosis, 1/3 dilated 3/3 (100%) (not vein without obvious quantified) cause) Study period: Mean age 35.5 (range, Needle No relationship to duration Surgical approach NS Follow-up duration: Selective outcome unclear 13-70) yrs, 5M:4F electromyography of symptoms unclear reporting: no (frequency of use unclear, 2 limbs positive) Presenting symptoms Surgical procedures NS Loss to follow-up: Source of funding: by limb: popliteal unclear unclear fossa, calf, lower thigh pain 9/9 (100%), foot numbness, paresthesia 9/9 (100%) Duration of Follow-up tests: Academic: no symptoms: 1-24 unclear mos SIGN level of evidence: 3 ih tal et Sinha NS, Not stated or not specified; SIGN, Scottish Intercollegiate Guidelines Network. 262.e25 262.e26 ih tal et Sinha

Appendix VI (online only). Included retrospective case-series on popliteal neurovascular entrapment

Outcomes and Risk of bias/SIGN Reference Patient characteristics Diagnostic adjuncts Classification of pathology Intervention follow-Up Level

Psathakis (1991)57 49 patients, 66 limbs Provocation Doppler Predominantly nerve Surgery 41/66 (62%), no Asymptomatic after Free from risk of bias? US used in 49 compression 42/66 surgery 25/66 (38%) surgery patients (unclear if [reasons NS] 40/41 (98%) patients assessed bilaterally, accuracy unclear) Single center 17/49 (34%) of Provocation ascending Predominantly arterial Posterior approach Outcome for Incomplete outcome (Germany) patients diagnosed phlebography used in compression 24/66 (frequency NS) asymptomatic data: unclear with bilateral 3 patients (unclear if operated limbs entrapment patients assessed unclear bilaterally) Study period: 1985- Mean age NS, 11M: Arteriography Muscle/band section Outcome for Selective outcome 1990 38F considered “invasive (frequency NS) nonoperated reporting: no and unnecessary” limbs unclear Presenting symptoms Provocation maneuvers: Follow-up duration: Source of funding: by limb: NS knee flexion and foot 48 mos unclear plantar flexion Presenting symptoms Loss to follow-up: Academic: no by patient: calf pain, unclear calf/foot paresthesia, lower limb swelling/discolouration/heaviness (frequencies NS) Duration of symptoms Follow-up tests: SIGN level of SURGERY VASCULAR OF JOURNAL NS Doppler US evidence: 3 No. of asymptomatic limbs unclear

NS, Not stated or not specified; SIGN, Scottish Intercollegiate Guidelines Network, US, ultrasound. aur 2012 January oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL Appendix VII (online only). Included prospective studies on popliteal vascular compression in asymptomatic subjects

Reference Patient characteristics Diagnostic adjuncts Classification of findings Conclusions of authors Risk of bias/SIGN level

Pailler (1988)58 107 subjects (unclear if all assessed Provocation Doppler Decrease or cessation of popliteal Positive Doppler US on plantar flexion Free from risk of bias? bilaterally) US used in all arterial flow on plantar flexion is insufficient to diagnose PAES subjects (plantar occurs in 50% of athletes and flexion) 30% of nonathletes Cohort Age NS, 107M:0F Subject selection: no study/nested case-control study No. of centers 53/107 (49.5%) ϭ “top level Blinding of assessors: no unclear (France) athletes” (no. of asymptomatic cases unclear), 53/107 (49.5%) ϭ nonathletic control group (all asymptomatic) Study period: NS 1/107 subjects unaccounted for Incomplete outcome data: no Selective outcome reporting: unclear Source of funding: unclear Academic: no SIGN level of evidence: 2– Leon (1992)59 100 asymptomatic subjects (200 Provocation DUS used By limb (DUS): 50%-100% Duplex US can identify significant Free from risk of bias? limbs) with no history of DVT in all subjects popliteal vein compression on popliteal vein compression on knee or venous insufficency (subjects seated, knee provocation ϭ extension in a significant proportion extension) 41/200 (20.5%), Ͻ50% of asymptomatic subjects popliteal compression on provocation ϭ 159/200 (79.5%) Cohort study Mean age 30 Ϯ 9 yrs, M/F NS Air plethysmography Bilateral venous compression in Those identified with significant Subject selection: unclear used to assess 14/27 subjects popliteal vein compression on DUS functional venous also have evidence of moderate- outflow obstruction severe functional venous outflow in 27 subjects with obstruction on air plethysmography positive DUS Single center (UK) Moderate-severe functional Blinding of assessors: no venous outflow obstruction on knee extension in 27/27 Study period: NS Incomplete outcome data: yes Selective outcome reporting: yes Source of funding: unclear Academic: yes SIGN level of evidence: 2–

Erdoes (1994)60 36 asymptomatic subjects (72 Provocation DUS used By limb (DUS): Popliteal artery Popliteal artery occlusion on plantar Free from risk of bias? limbs) in all subjects occlusion on provocation ϭ flexion can be demonstrated in a (subjects prone, knee 38/72 (53%), no occlusion on significant no. of asymptomatic extension, active and provocation ϭ 34/72 (47%) subjects on DUS al et Sinha passive foot (none occluded after exercise) dorsiflexion and plantar flexion) Cohort Mean age 26 (range, 18-42) yrs, Nonoccluders on All nonoccluders (34 limbs) No significant difference between Subject selection: no study/nested 21M:15F provocation DUS showed mean decrease in ABPI athletes and nonathletes in case-control study exercised to heart- of 0.15 on provocation prevalence of occlusion 262.e27 rate of Ն140 beats/ min and rescanned 262.e28

Appendix VII (online only). Continued

Reference Patient characteristics Diagnostic adjuncts Classification of findings Conclusions of authors Risk of bias/SIGN level ih tal et Sinha Single center (USA) 16/36 (44%) ϭ athletic (“cross- Provocation MRI and 72/72 limbs showed popliteal MRI can disclose anatomy of the Blinding of assessors: no country runners”), 20/36 (56%) ϭ MRA in 14/36 vein occlusion popliteal fossa (and so rule out nonathletic (“normally active”) subjects (28 limbs, anatomical entrapment) 15 limbs positive on DUS) Study period: NS Note: muscle fatigue MRI/MRA: popliteal artery Incomplete outcome data: yes during provocation occlusion on provocation MRI noted to be a detected in 9 limbs (60% problem correlation with DUS), no anatomic abnormalities detected Selective outcome reporting: yes Source of funding: unclear Academic: yes SIGN level of evidence: 2– Chernoff (1995)61 13 asymptomatic subjects (13 Provocation MRI and By limb (MRI/MRA): Ͼ99% Impairment of popliteal artery flow Free from risk of bias? limbs: only right limbs MRA used in all popliteal artery occlusion on occurs on plantar flexion in examined) subjects (plantar provocation ϭ 9/13 (69%), asymptomatic subjects as flexion) 75-99% popliteal artery demonstrated by both MRI/MRA occlusion on provocation ϭ and ABPI 3/13 (23%), Ͻ50% popliteal artery occlusion on provocation ϭ 1/13 (8%) Cohort study Mean age 31.9 (range, 27-44) yrs, Provocation ABPI used MRI demonstrates muscular Study selection: no 9M:4F in all subjects compression of popliteal artery in at 2 levels (plantaris/gastrocnemius and plantaris/popliteus) in 13/13 Single center (USA) 1/13 ϭ “marathon runner”, 12/ Note: muscle fatigue ABPI: occlusion ϭ 9/13 (69%), Blinding of assessors: no 13 ϭ “physically active” during provocation decrease of at least 0.15 ϭ 3/ MRI noted to be a 13 (23%), no change ϭ 1/ problem 13 (8%) Study period: NS 100% correlation between MRI/ Incomplete outcome data: yes MRA and ABPI Selective outcome reporting: yes Source of funding: unclear

Academic: yes SURGERY VASCULAR OF JOURNAL SIGN level of evidence: 2– Akkersdijk (1995)62 16 asymptomatic subjects (32 Provocation DUS used By limb (DUS on active plantar Active plantar flexion is the only Free from risk of bias? limbs) in all subjects flexion) at most distal level: provocative maneuver that influences (subjects prone, Popliteal artery occlusion ϭ popliteal artery flow on DUS active and passive 19/32 (59%), increased PSV ϭ foot dorsiflexion and 4/32 (13%), decreased PSV ϭ plantar flexion) 4/32 (13%), no change in PSV ϭ 5/32 (15%) Cohort Mean age 25 (range, 20-27) yrs, Popliteal artery assessed Less significant results noted Reduction of flow in the popliteal Subject selection: unclear

study/nested 12M:4F at 3 levels (above above knee and at level of knee artery on active foot plantar flexion 2012 January case-control study knee, at level of knee, for active plantar flexion is a physiologic phenomenon and of proximal to limited value in diagnosing PAES trifurcation) oue5,Nme 1 Number 55, Volume SURGERY VASCULAR OF JOURNAL Appendix VII (online only). Continued

Reference Patient characteristics Diagnostic adjuncts Classification of findings Conclusions of authors Risk of bias/SIGN level

Single center 8/16 (50%) ϭ “semi-professional Results not significant with other No significant difference between Blinding of assessors: no (Netherlands) rowers”, 8/16 (50%) ϭ provocation maneuvers athletes and nonathletes nonathletic (“without intensive physical training”) Study period: NS Incomplete outcome data: yes Selective outcome reporting: yes Source of funding: unclear Academic: yes SIGN level of evidence: 2– Hoffman (1997)63 42 asymptomatic subjects (84 Provocation DUS used By limb (DUS): Popliteal artery Popliteal artery occlusion on plantar Free from risk of bias? limbs) in all subjects occlusion on provocation ϭ flexion occurs in asymptomatic (subjects prone, 67/84 (80%), no occlusion on subjects plantar flexion) provocation ϭ 17/84 (20%) Cohort Mean age 30.6 Ϯ 12.1 yrs, 25M: Provocation MRI done Bilateral popliteal artery occlusion No significant difference between Subject selection: unclear study/nested 17F in 1 patient: also in 30/42 subjects athletes and nonathletes in case-control study showed bilateral prevalence of occlusion popliteal artery occlusion but no anatomic abnormality demonstrated Single center 18/42 (43%) ϭ “highly trained Occlusion requires less force in athletes Blinding of assessors: no (Switzerland) athletes”, 4/42 (57%) ϭ compared to nonathletes (P Ͻ .02) nonathletes Study period: NS Incomplete outcome data: yes Selective outcome reporting: yes Source of funding: unclear Academic: yes SIGN level of evidence: 2– De Almeida 42 asymptomatic subjects (84 Provocation ABPI used By limb (ABPI): 7/84 (8.3%) Using provocation DUS as a gold Free from risk of bias? (2004)64 limbs) in all subjects (active showed reduced ABPI with standard reference test; provocation plantar flexion) provocation ABPI and provocation Doppler US have good specificity (1 and 0.9, respectively) and sensitivity (0.7 and one) in identification of popliteal artery compression Cohort/nested case- Mean age 20 Ϯ 4 yrs, M/F NS Provocation Doppler 17/84 (20.2%) showed altered No significant difference between Subject selection: unclear control study US used in all Doppler signal indicating athletes and nonathletes in subjects (active popliteal artery compression prevalence of compression plantar flexion) during provocation Single center (Brazil) 21/42 (50%) ϭ “indoor soccer Provocation DUS used Blinding of assessors: no players”, 21/42 (50%) ϭ in all subjects (active nonathletic (“sedentary”) plantar flexion)

Study period: NS DUS: 6/84 (7.1%) showed Incomplete outcome data: yes al et Sinha popliteal artery occlusion on provocation 4/84 (4.7%) showed popliteal Selective outcome reporting: yes artery stenosis on provocation Bilateral compression/occlusion Source of funding: unclear

on DUS found in 4/42 262.e29 subjects (9.5%) Academic: yes SIGN level of evidence: 2– 262.e30 ih tal et Sinha

Appendix VII (online only). Continued

Reference Patient characteristics Diagnostic adjuncts Classification of findings Conclusions of authors Risk of bias/SIGN level

Pillai (2008)65 88 asymptomatic subjects (176 Provocation Doppler By patient (Doppler US): 16/ Variations in the extent of attachment Free from risk of bias? limbs) US used in all 88 (18%) bilateral occluders; towards the midline of the medial subjects (active 8/88 (9%) unilateral occluders; head of gastrocnemius represents a plantar flexion) 58/88 (67%) bilateral normal embryologic variant nonoccluders; 6/88 (7%) not classifiable Cohort/nested case- Mean age 50 (M), 38.4 (F) yrs, Provocation DUS used 12/16 bilateral occluders scanned The increased extent of midline Subject selection: no control study 50M:38F in 22 subjects (active with DUS (10/12 noted to attachment in asymptomatic plantar flexion) occlude bilaterally and occluders may represent a group progressed to MRI) who are prone to develop symptoms (eg, as a result of muscular hypertrophy) and who would then otherwise be classed as having functional PAES Single center (South 0/88 ϭ athletic Bilateral static MRI 10/58 bilateral nonoccluders Blinding of assessors: yes Africa) used in 20 subjects scanned with DUS (10/10 (40 limbs assessed) noted to not occlude bilaterally and progressed to MRI) Study period: NS 88/88 ϭ “normally active adult Note: muscle fatigue MRI: 10 bilateral occluders (20 Incomplete outcome data: yes volunteers” during provocation limbs), 10 bilateral MRI noted to be a nonoccluders (20 limbs) problem Exclusion and inclusion criteria for Note: provocation More extensive attachment of Selective outcome reporting: yes recruitment of cohort stated ABPI felt to be medial head of gastrocnemius unreliable toward midline noted in occluders vs nonoccluders Source of funding: yes Academic: no SURGERY VASCULAR OF JOURNAL SIGN level of evidence: 2–

ABPI, Ankle-brachial pressure index; DUS, duplex ultrasound; DVT, deep vein thrombosis; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging; NS, not stated or not specified; PAES, popliteal artery entrapment syndrome; PSV, peak systolic velocity; SIGN, Scottish Intercollegiate Guidelines Network; US, ultrasound. aur 2012 January