Degenerative Lumbar Spinal Stenosis: Evaluation and Management

Review Article Degenerative Lumbar Spinal Stenosis: Evaluation and Management

Abstract Paul S. Issack, MD, PhD Degenerative lumbar spinal stenosis is caused by mechanical Matthew E. Cunningham, MD, factors and/or biochemical alterations within the intervertebral disk PhD that lead to disk space collapse, facet joint hypertrophy, soft-tissue Matthias Pumberger, MD infolding, and osteophyte formation, which narrows the space available for the thecal sac and exiting nerve roots. The clinical Alexander P. Hughes, MD consequence of this compression is neurogenic claudication and Frank P. Cammisa, Jr, MD varying degrees of leg and back pain. Degenerative lumbar spinal stenosis is a major cause of pain and impaired quality of life in the elderly. The natural history of this condition varies; however, it has not been shown to worsen progressively. Nonsurgical management consists of nonsteroidal anti-inﬂammatory drugs, physical therapy, and epidural steroid injections. If nonsurgical management is unsuccessful and neurologic decline persists or progresses, surgical treatment, most commonly laminectomy, is indicated. Recent prospective randomized studies have demonstrated that surgery is superior to nonsurgical management in terms of controlling pain and improving function in patients with lumbar spinal stenosis.

egenerative lumbar spinal als, particularly the Spine Patient Dstenosis is a major cause of Outcomes Research Trial (SPORT) pain and dysfunction in the elderly. study, have provided compelling evi- Most patients report leg and/or back dence that decompressive surgery is pain and have progressive symptoms an effective treatment that provides after walking or standing for even pain relief and functional improve- short periods of time.1 Diagnosis is ment in patients with degenerative typically made based on clinical his- lumbar spinal stenosis.2,3 tory and physical examination and is confirmed on imaging studies. In most cases, treatment should begin Etiology with nonsurgical management. In the From the Hospital for Special Surgery, New York, NY. rare case of a progressive neurologic Lumbar spinal stenosis is a reduction deficit or cauda equina syndrome, in the volume of the central spinal J Am Acad Orthop Surg 2012;20: urgent surgical decompression is in- 527-535 canal, the lateral recesses, and/or dicated. In most cases, the natural neuroforamina that decreases the http://dx.doi.org/10.5435/ history of degenerative lumbar steno- JAAOS-20-08-527 space available for the thecal sac sis is variable and does not follow a and/or exiting nerve roots.4,5 Ap- Copyright 2012 by the American progressively deteriorating course. Academy of Orthopaedic Surgeons. proximately 20% of the time, this Recent prospective randomized tri- condition is caused or exacerbated

August 2012, Vol 20, No 8 527 Degenerative Lumbar Spinal Stenosis: Evaluation and Management by congenital causes, such as failure mains unclear given the lack of pro- weakness (43%) reported.1 These of the posterior elements to develop, spective studies with observational symptoms may be localized to the resulting in short pedicles and cohorts. Johnsson et al9 followed 32 buttocks and can radiate to the laminae.4-6 More commonly, lumbar untreated patients with spinal steno- lower extremities in a proximal to stenosis is the result of degenerative sis over 49 months. Symptoms of distal fashion. Patients with lumbar changes. The degenerative process is neurogenic claudication remained spondylotic stenosis have diminished thought to be initiated by disk dehy- unchanged in 22 patients (70%), standing and walking tolerance; dration, disk bulging, and collapse of symptoms improved in 5 patients however their ability to walk dis- the disk space, which sets in motion (15%), and symptoms worsened in 5 tances can be increased by ambulat- the sequence of events that result in patients (15%). None of the patients ing with the spine in a flexed- narrowing of the spinal canal. Disk had severe deterioration. forward posture such as that used space narrowing and loss of the nor- Cauda equina syndrome is a rare when pushing a shopping cart.4 Typi- mal shock absorptive capacity of the condition caused by compression of cally, spinal extension narrows the spinal segment results in an increased the lumbosacral nerve roots within spinal canal and worsens neurogenic transfer of stress to the facet joints, the spinal canal that produces vary- symptoms, whereas spinal flexion which accelerates facet joint cartilage ing degrees of motor weakness; sad- and sitting increases the diameter of degeneration and osteophyte forma- dle anesthesia; and bowel, bladder, the spinal canal, partially alleviating tion.5,7 Facet joint hypertrophy, in- and gait dysfunction. Acute presenta- symptoms.4,5,11 folding of the ligamentum flavum, tion frequently occurs in patients On physical examination, back and development of bulging disk os- with large central disk herniation, pain or lower extremity symptoms teophyte complexes all contribute to whereas delayed presentation often can be elicited with lumbar exten- circumferential narrowing of the cen- occurs in patients with chronic spinal sion. Objective sensory findings such tral spinal canal and lateral recesses, stenosis. Surgical decompression as diminished sensation along a spe- that is, the area of the spine bordered should be performed as soon as pos- cific dermatome or motor weakness by the superior articular facet poste- sible to avoid progression of neuro- suggest long-standing neural com- riorly, the disk and vertebral body logic deficits.10 pression. Radicular symptoms are anteriorly, the thecal sac medially, most commonly seen in patients with and the pedicle laterally. These lateral recess or foraminal stenosis. stenotic changes cause neural com- Diagnosis Patients with spondylotic stenosis pression that presents clinically as may also present with neurogenic or variable degrees of leg and back Clinical Presentation vascular claudication. The orthopae- pain, as well as gait deterioration Patients with lumbar spondylotic dic surgeon must distinguish neuro- and other neurologic deficits (eg, stenosis most commonly present genic claudication from vascular numbness and weakness). with neurogenic claudication and re- claudication; patients with vascular port discomfort while standing as claudication may present with di- Natural History well as diminished walking capacity. minished walking capacity due to In a series of 68 patients with lumbar cramping of lower extremity muscles Prevalence of degenerative lumbar spinal stenosis confirmed with mye- on exertion. Unlike patients with spondylosis in the general popula- lography and surgery, neurogenic neurogenic claudication, patients tion ranges from 20% to 25% and claudication was observed in 94% of with vascular claudication cannot increases with age >50 years.8 The patients, with primary symptoms of improve walking tolerance with pos- natural history of this disease re- pain (93%), numbness (63%), or tural changes. Patients with neuro-

Dr. Hughes or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of NuVasive; serves as a paid consultant to BOSS Medical, Bovie Medical Corporation, Orthovita, and SpineView; and has received research or institutional support from NuVasive. Dr. Cammisa or an immediate family member has received royalties from NuVasive; serves as a paid consultant to Alphatec Spine, Centinel Spine, Disc Motion Technologies, HealthpointCapital Partners, IVY Healthcare Partners, Mazor Surgical Technologies, NuVasive, Orthogem, Orthovita, Paradigm Spine, Spinal Kinetics, Spinal Partners III, and Viscogliosi Brothers; and has stock or stock options held in Alphatec Spine, BI Members, Centinel Spine, Disc Motion Technologies, HealthpointCapital Partners, IVY Healthcare Partners, Mazor Surgical Technologies, NuVasive, Orthovita, Orthopaedic Investment Partners, Paradigm Spine, Small Bone Innovations, Spinal Kinetics, and Viscogliosi Brothers. None of the following authors or any immediate family member has received anything of value from or owns stock in a commercial company or institution related directly or indirectly to the subject of this article: Dr. Issack, Dr. Cunningham, and Dr. Pumberger.

528 Journal of the American Academy of Orthopaedic Surgeons Paul S. Issack, MD, PhD, et al

Figure 1

A, Parasagittal T2-weighted magnetic resonance image of the lumbar spine demonstrating multilevel lumbar spondylosis, with disk dehydration (arrowhead), disk protrusion (arrow), and central canal narrowing at L2-S1. Hypertrophic changes in the ligamentum ﬂavum and facet joint are most prominent at L4-S1. B, Axial T2-weighted magnetic resonance image of the L4-5 interspace showing hypertrophy of the facet joint (arrowhead) and ligamentum ﬂavum (arrow), causing severe central canal and lateral recess stenosis. C, Parasagittal T1-weighted magnetic resonance image of the lumbar spine demonstrating loss of epidural fat (arrow) about the lower lumbar exiting nerve roots (L3, L4, and L5) and neuroforaminal stenosis. genic claudication typically cannot involved as well as any associated stenosis with compression of travers- alleviate symptoms simply by ceasing pathology. Plain standing AP and lat- ing nerve roots. The degree of spinal to walk; these patients must sit or eral radiographs may demonstrate stenosis is best evaluated on MRI be- adopt a flexed-foward posture to al- spondylolisthesis, disk space narrow- cause it can demonstrate disk degen- leviate symptoms. Patients with vas- ing, end plate sclerosis, osteophytes, eration or herniation, hypertrophy of cular claudication have similar and facet hypertrophy.13 Lateral and the ligamentum flavum and facet symptoms whether ambulating or flexion and extension stress radio- capsule, and narrowing of the central riding a stationary bicycle, whereas graphs may be helpful in determining canal and lateral recess (Figure 1, A patients with neurogenic claudica- whether spondylolisthesis is mobile and B). Parasagittal T1-weighted tion have diminished symptoms of and may demonstrate a slip that is magnetic resonance images may claudication while in a seated posi- not visible on the plain standing lat- demonstrate loss of epidural fat at tion. In addition, patients with vas- eral view. the exiting nerve root or frank nerve cular claudication may have evidence No consensus exists regarding the root deformation, which suggests en- of vascular changes such as trophic definition of spinal stenosis in terms trapment of the root in the foram- changes in the skin of the legs and of the diameter of the spinal canal or ina13 (Figure 1, C). Radiographic feet as well as diminished distal puls- area measurements. Often, the de- findings that indicate likely instabil- es; this is typically not observed in gree of soft-tissue compression that ity include the presence of gapped patients with neurogenic claudica- can be caused by ligament infold- facets on axial CT scan and fluid- 12 tion. ing is underestimated when these filled facets visible on axial T2- measurements are used to assess spi- weighted magnetic resonance im- Radiographic Evaluation nal stenosis on CT. Furthermore, ages.14 In patients without lumbar Clinical history and physical exami- measurements of midsagittal and spinal stenosis, supine magnetic reso- nation aid in diagnosis of degenera- anterior-posterior canal diameter nance images show sedimentation of tive lumbar spinal stenosis. Typically, may appear normal in patients with the lumbar nerve roots to the dorsal imaging studies are used to confirm trefoil-shaped spinal canals who part of the thecal sac as a result of the diagnosis and identify the levels have clinically relevant lateral recess gravity. The absence of normal sedi-

August 2012, Vol 20, No 8 529 Degenerative Lumbar Spinal Stenosis: Evaluation and Management mentation is a positive sign of lum- Physical therapy, with an emphasis such as vascular injury, hematoma bar spinal stenosis.15 on abdominal flexion exercises and formation, and paralysis.23,24 Further- When MRI cannot be obtained, core muscle strengthening, may help more, clear evidence-based guide- myelography followed by CT may be to improve muscle strength, maintain lines are lacking regarding the num- used to assess the degree and loca- range of motion, and improve global ber and frequency of injections 18 tion of stenosis; these imaging mo- functioning. In a randomized clini- needed to manage spinal stenosis. dalities are helpful for preoperative cal trial that compared two physical identification of locations that re- therapy programs for patients with Surgical quire decompression. Radiographic lumbar spinal stenosis, 18 of 29 pa- Surgery is indicated in patients with changes are often seen in patients tients (62%) treated with a 6-week clinical and radiographic evidence of who are asymptomatic; therefore, regimen of manual physical therapy, correlation of imaging results with body weight supported treadmill spinal stenosis who have intractable clinical findings is essential for iden- walking, and exercise demonstrated pain, altered quality of life, or sub- tification of relevant pathology. In a improvement in disability, satisfac- stantially diminished functional ca- study of 67 asymptomatic patients tion, and treadmill walking tests at pacity and have either failed nonsur- who had no reports of low back 1-year follow-up.19 gical treatment or are not candidates 25 pain, sciatica, or neurogenic claudi- Epidural steroid injections can also for nonsurgical treatment. Surgery cation, Boden et al16 reported that be used to provide temporary relief can predictably address positional MRI findings in patients aged ≥60 of radicular symptoms in select pa- back pain and neurogenic claudica- years were abnormal on approxi- tients.20 In a prospective study of 34 tion, but may not adequately address mately 57% of the scans, with 21% patients with radicular pain caused pain secondary to degenerative disk of scans demonstrating spinal steno- by degenerative lumbar spinal steno- disease (eg, low back pain, referred sis. sis, Botwin et al21 treated patients pain).2,3,25-27 with fluoroscopy-guided lumbar The method of surgical interven- transforaminal epidural injections. tion is based on the location and Management The authors reported that 75% of character of stenosis. Spinal stenosis patients noted at least a >50% re- usually occurs as the result of a Nonsurgical duction in pain scores, 64% had im- global degenerative process that in- The goals of therapy in patients with proved walking tolerance, and 57% volves the central canal, lateral re- degenerative lumbar stenosis are to had improved standing tolerance at cesses, neuroforamina, or a combina- alleviate pain and improve func- 1-year follow-up. Other studies have tion of these structures. Compression tion. Nonsteroidal anti-inflamma- reported temporary improvement in may be isolated or may extend to tory drugs (NSAIDS) may temporar- pain and function following epidural multiple levels and can involve the ily and partially alleviate pain. In injection. Tran et al22 performed a central or lateral nerve roots, those general, narcotic analgesics should meta-analysis of randomized con- in the foramen, or a combination of be avoided or used on a short-term trolled trials to examine nonsurgical all three. Radicular symptoms or basis preoperatively and as needed in management of lumbar spinal steno- motor weakness along specific nerve the immediate postoperative period. sis, including the use of lumbar epi- root distributions require careful as- Both NSAIDs and narcotic analgesics dural injection used to manage lum- sessment of the lateral recess and fo- can be especially problematic in the bar spondylotic stenosis. They ramen.4,6 Relative stability of the dis- elderly patient population. NSAIDs determined that there may be no eased segment should also be have been associated with an in- added benefit in adding steroids to assessed. Hypermobile segments (ie, creased risk of bleeding, gastrointes- the anesthetic injection. Additionally, segments demonstrating spondylolis- tinal, liver, renal, cardiovascular, and concerns exist regarding the effects thesis, lateral listhesis, widened fac- central nervous system complications on bone quality and blood glucose ets with fluid visible on MRI) adja- in the elderly.17 Narcotic analgesics levels with repetitive use of ste- cent to more normal segments may are associated with significant altera- roids.4,20 In patients with severe neu- require stabilization with in situ fu- tions in normal mood and sleep- rologic deficit, including limited sion techniques or instrumented ar- wake cycle as well as gastrointestinal walking capacity or cauda equina throdesis and fusion. Neurogenic complications and potential respira- syndrome, epidural steroid injections claudication with central canal tory suppression; these symptoms are can exacerbate symptoms; case re- stenosis may require laminectomy, magnified in the elderly population. ports have described complications laminotomy, or indirect reduction

530 Journal of the American Academy of Orthopaedic Surgeons Paul S. Issack, MD, PhD, et al

Figure 2 expose the neuroforamina and exiting nerve roots, which may be decompressed using Kerrison rongeurs (Figure 2, D). A ball-tipped probe, Woodson elevator, or angled dural separator should be used to assess the anteroposterior and proximal- distal volume of the neuroforamina.6 Several studies have evaluated outcomes of decompressive laminectomy for spinal stenosis. Some of these studies reported on outcomes of decompressive laminectomy and nonsurgical treatment in a cohort of 148 patients with symptomatic lumbar stenosis who were followed for 10 years.26-28 Eighty-one patients underwent laminectomy, and 67 received nonsurgical treatment, with both groups assessed at 1, 4, and 8 to 10 years following treatment.26 Leg or back pain was substantially improved in 55% of patients in the surgical group and 28% in the nonsurgical group at 1-year follow-up.26 However, these differences became less substantial over time; at 8- to 10-year follow-up, leg or back pain was significantly improved in 54% of surgically treated patients compared with 42% of nonsurgically treated patients.28 These studies were A, Illustration demonstrating resection of the spinous processes and limited by their nonrandomized de- detachment of ligamentum ﬂavum from the ventral aspect of the lamina with sign in which potential confounders a curet. B, Laminectomy and central decompression with a Kerrison rongeur. cannot be excluded, the high rate of C, Partial medial facetectomy and foraminotomy are performed with a 45° loss to follow-up, and various de- Kerrison rongeur. D, The superior tip of the superior facet is resected with a 45° Kerrison rongeur for decompression of the neuroforamen. grees of decompression; these issues make it difficult to assess the value of decompression surgery.26-28 techniques for decompression of the rior elements is performed from the More recently, prospective ran- central canal. These techniques can midline to the lateral pars interartic- domized studies have rigorously be performed via traditional open ularis and facets with great care evaluated surgical management of approaches or minimally invasive taken to avoid damage to the facet spinal stenosis.3,29,30 Amundsen et al29 techniques. joint or pars interarticularis. After reported on the results of 100 pa- resection of the spinous processes tients with symptomatic lumbar spi- Laminectomy and superficial dorsal lamina, central nal stenosis who were assigned to Laminectomy is performed with the decompression is performed with re- either surgical or nonsurgical treat- patient positioned prone on a sup- moval of the midline laminae and ment. A partial randomization was portive frame that allows the abdo- underlying ligamentum flavum (Fig- done, with 31 patients assigned to ei- men to hang free to decrease epi- ure 2, A-C). Partial medial facetecto- ther nonsurgical or surgical treat- dural venous pressure and surgical mies can then be performed to de- ment groups. At 4-year follow-up, site bleeding. Exposure of the poste- compress the lateral recess and excellent or fair results were ob-

August 2012, Vol 20, No 8 531 Degenerative Lumbar Spinal Stenosis: Evaluation and Management served in 9 of 18 patients in the non- vational cohort; however, many pa- Minimally Invasive Surgical surgical group and 10 of 13 patients tients in the nonsurgical group opted Approaches in the surgical group. Malmivaara to have surgery. At 2-year follow-up, Compared with traditional open et al30 evaluated 94 patients with 193 of 289 patients (67%) in the techniques, minimally invasive sur- lumbar spinal stenosis treated either randomized cohort had undergone gery (MIS) for management of spinal surgically (50 patients) or nonsurgi- surgery, whereas 157 patients (43%) stenosis results in better preservation cally (44 patients) in randomized in the observational cohort received of posterior musculature, diminished multicenter trial. The surgical group nonsurgical care and underwent sur- intraoperative bleeding, and requires less recovery time.35,36 MIS ap- included 10 patients treated with in- gery. As-treated analysis, which com- proaches for stenosis include lamin- strumented posterolateral fusion. At bined both cohorts, showed that sur- 2-year follow-up, disability, leg pain, otomy, microendoscopic laminotomy gery had a marked advantage over and back pain were improved to a with tubular retractors, and lamino- nonsurgical treatment, with substan- greater degree in the surgical group plasty. Although MIS approaches tial decreases in pain and improve- than in the nonsurgical group. Walk- have some advantages over open ment in physical function as mea- ing ability did not differ between the procedures, the economic value and sured by the Medical Outcomes two treatment groups. A drawback cost-effectiveness of MIS requires Study 36-item Short-Form General 37 of the study is that inclusion of pa- further investigation. tients treated with fusion makes it Health Survey and the modified Os- difficult to attribute good outcomes westry Disability Index (ODI). These Laminotomy to decompression alone. Crossover differences remained significant at 2 Laminotomy involves removal of a 2,3 of the patient population is another and 4 years. small portion of one side of the lam- limitation of this study; 9% of the Complications associated with ina. Resection of the distal half of nonsurgical group underwent surgi- laminectomy include infection, dural the superior hemilamina is often nec- cal intervention due to exacerbation tear, epidural hematoma, and insta- essary to identify and remove the in- of symptoms, and 8% of the decom- bility. One study reported that, fol- sertion site of the ligamentum fla- pressive surgery group did not un- lowing laminectomy, 2 of 103 pa- vum. Contralateral decompression dergo surgery due to relief of symp- tients (2%) with lumbar stenosis can be performed with preservation toms, thereby further confounding developed deep infection, requiring of the spinous processes and supra- the researchers’ ability to detect dif- irrigation and débridement.31 Re- spinous and interspinous ligaments ferences between the groups. cently, a 10.5% incidence of durot- by tilting the operating table away Effectiveness of surgical manage- omy was reported in 389 patients from the surgeon. Using an operating ment of lumbar spinal stenosis was who underwent laminectomy for microscope, the contralateral liga- evaluated in the SPORT study. This lumbar degenerative spondylolisthe- mentum can be visualized and re- prospective randomized multicenter sis. No significant differences in pain sected and then the lamina can be trial had three study arms based on or physical function based on Medi- undercut38,39 (Figure 3). Toyoda diagnosis: lumbar disk herniation, cal Outcomes Study 36-item Short et al38 reported on 57 patients who degenerative spondylolisthesis or spi- Form scores or ODI were observed underwent bilateral decompression nal stenosis.2,3 Patients with spinal at 1, 2, 3, and 4 years in patients via unilateral laminotomies. Of these stenosis without spondylolisthesis with or without durotomy, which patients, 27 had lumbar spinal steno- who had symptoms for at least 12 suggests that incidental durotomy sis without instability, 20 had degen- weeks and failed nonsurgical treat- does not significantly affect out- erative lumbar spondylolisthesis, and ment were enrolled in the spinal come.32 Epidural hematoma follow- 10 had degenerative lumbar scolio- stenosis arm of the study. These pa- ing laminectomy is rare and requires sis. At a mean 6-year follow-up, the tients were assigned to either a ran- urgent surgical decompression to average Japanese Orthopaedic Asso- domized or an observational cohort avoid neurologic deficit.33 In a study ciation (JOA) score improved from and underwent decompressive sur- of 27 patients treated with posterior 13.8 ± 3.6 points preoperatively to gery or nonsurgical care, respec- spinal decompression procedures, 22.6 ± 4.7 points at final follow-up. tively. Nonsurgical care consisted of the incidence of postlaminectomy in- At final follow-up, no significant dif- physical therapy, education and/or stability was 3.7%; this complication ferences in JOA score or percentage counseling with home exercise in- can be avoided by preserving the of slippage were noted among pa- struction, and NSAIDs. Initially, 365 pars interarticularis and at least 50% tients with these three diagnoses. patients were assigned to the obser- of the facet joints.34 This technique is limited because of

532 Journal of the American Academy of Orthopaedic Surgeons Paul S. Issack, MD, PhD, et al

Figure 3 compared with 36% of control patients. Tuschel et al44 recently reported on 46 patients with spinal stenosis who underwent implantation of the X-STOP device. At a mean 40-month follow-up, no improvement was noted, and the revi- sion rate was approximately 30%. Most revisions occurred within the first year. In addition, there is evidence that implantation of these devices may not improve outcomes and in fact may worsen neural compression in severely stenotic patients.45,46 Indications for the use of these implants are not well defined, and long- term studies are lacking at this time. A, Illustration demonstrating microdecompression. The shaded area shows the ipsilateral decompression. The dashed lines represent the contralateral Economics area to be decompressed under the midline structures. B, Axial view of the A cost analysis performed using a contralateral decompression. The contralateral exiting nerve root is protected during the procedure. subset of patients with spinal stenosis from the SPORT study showed that surgical management of spinal the difficulty in accessing stenosis in access without extensive facetec- stenosis improved health to a greater the lateral canal and foramen. tomy.42 extent than nonsurgical care (quality adjusted life year [QALY] gained, Microendoscopic Laminotomy Interspinous Process Devices 0.17) at a cost of $77,600 per QALY In a prospective study of 53 patients Recently, interspinous process de- gained at 2-year follow-up.47 At 4-year with spinal stenosis, Pao et al40 per- vices have been used to manage lum- follow-up, QALY gains were main- formed microendoscopic laminot- bar spinal stenosis. These implants tained (0.22) and costs per QALY omy using a tubular retractor and a block spinal extension at the level of gained decreased to $59,400.48 The fiberoptic endoscopic system. Of the facet joint and limit canal nar- authors concluded that the economic these patients, 45 (85%) were satis- rowing associated with spinal exten- value of surgery for spinal stenosis fied with treatment at an average 16- sion. In a prospective randomized compares favorably with many month follow-up. Significant im- controlled multicenter trial, Zu- health interventions.47,48 provement in ODI and JOA scores cherman et al43 analyzed outcomes of was noted, and 40 patients (80%) 191 patients with symptomatic spi- had good to excellent results. Com- nal stenosis. Ninety-one patients Summary plication rates were high and in- were treated nonsurgically and 100 cluded dural tears in five patients were treated with the X-STOP inter- Degenerative lumbar spinal stenosis and transient neuralgia in four spinous implant (Medtronic, Mem- is a major cause of impaired quality patients. Khoo and Fessler41 com- phis, TN). At 2-year follow-up, of life and diminished functional ca- pared microendoscopic decompres- symptom scores improved by 45% pacity in the elderly. Patients com- sive laminotomy with open decom- over baseline in patients treated with monly present with neurogenic clau- pression in patients with lumbar the X-STOP implant compared with dication and diminished standing spinal stenosis and noted that the mi- 7% improvement in the control and walking tolerance; however, croendoscopic procedure was associ- group. The X-STOP group had a their ability to walk distances can be ated with reduced blood loss, shorter 44% mean improvement in function increased by ambulating with the postoperative hospital stay, and di- compared with no improvement in spine in a flexed-forward posture. minished use of narcotics. A draw- the control group. In addition, 73% On physical examination, back pain back of this technique is that the ip- of patients treated with the X-STOP or lower extremity symptoms can of- silateral lateral recess is difficult to device were satisfied with surgery ten be elicited with lumbar exten-

August 2012, Vol 20, No 8 533 Degenerative Lumbar Spinal Stenosis: Evaluation and Management sion. Radicular symptoms may be Outcomes Research Trial. Spine (Phila nonsteroidal anti-inflammatory drugs seen in patients with lateral recess or Pa 1976) 2010;35(14):1329-1338. (NSAIDs) be prescribed to the older adult? Drugs Aging 2010;27(10):775- foraminal stenosis. 3. Weinstein JN, Tosteson TD, Lurie JD, 789. et al: Surgical versus nonsurgical therapy Plain AP and lateral radiographs for lumbar spinal stenosis. N Engl J Med 18. Daffner SD, Wang JC: The may demonstrate spondylolisthesis, 2008;358(8):794-810. pathophysiology and nonsurgical disk space narrowing, end plate scle- treatment of lumbar spinal stenosis. Instr 4. Djurasovic M, Glassman SD, Carreon Course Lect 2009;58:657-668. rosis, osteophytes, and facet hyper- LY, Dimar JR II: Contemporary management of symptomatic lumbar 19. Whitman JM, Flynn TW, Childs JD, trophy. MRI can best demonstrate spinal stenosis. Orthop Clin North Am et al: A comparison between two the degree of narrowing in the cen- 2010;41(2):183-191. physical therapy treatment programs for tral canal and lateral recess. Because patients with lumbar spinal stenosis: A 5. Verbiest H: Pathomorphologic aspects of randomized clinical trial. Spine (Phila Pa the natural history of spinal stenosis developmental lumbar stenosis. Orthop 1976) 2006;31(22):2541-2549. Clin North Am 1975;6(1):177-196. is generally benign but progressive, 20. Riew KD, Park JB, Cho YS, et al: Nerve initial treatment with NSAIDs; phys- 6. Singh K, Samartzis D, Biyani A, An HS: root blocks in the treatment of lumbar Lumbar spinal stenosis. J Am Acad ical therapy, with an emphasis on radicular pain: A minimum five-year Orthop Surg 2008;16(3):171-176. follow-up. J Bone Joint Surg Am 2006; core strengthening; and epidural ste- 7. Buckwalter JA: Aging and degeneration 88(8):1722-1725. roid injections may be beneficial. of the human intervertebral disc. Spine 21. Botwin KP, Gruber RD, Bouchlas CG, Surgical management is indicated (Phila Pa 1976) 1995;20(11):1307-1314. et al: Fluoroscopically guided lumbar following failure of nonsurgical mea- 8. Kalichman L, Cole R, Kim DH, et al: transformational epidural steroid Spinal stenosis prevalence and injections in degenerative lumbar sures. Recent prospective random- association with symptoms: The stenosis: An outcome study. Am J Phys ized controlled studies have demon- Framingham Study. Spine J 2009;9(7): Med Rehabil 2002;81(12):898-905. strated a definite advantage of 545-550. 22. Tran de QH, Duong S, Finlayson RJ: surgery over nonsurgical treatment 9. Johnsson KE, Rosén I, Udén A: The Lumbar spinal stenosis: A brief review of natural course of lumbar spinal stenosis. the nonsurgical management. Can J in decreasing pain and improving Clin Orthop Relat Res 1992;(279):82- Anaesth 2010;57(7):694-703. function in patients with degenera- 86. 23. Huntoon MA, Martin DP: Paralysis after tive spinal stenosis. Decompressive 10. Spector LR, Madigan L, Rhyne A, transforaminal epidural injection and laminectomy is the most commonly Darden B II, Kim D: Cauda equina previous spinal surgery. Reg Anesth Pain Med 2004;29(5):494-495. performed procedure used to address syndrome. J Am Acad Orthop Surg 2008;16(8):471-479. 24. Xu R, Bydon M, Gokaslan ZL, global stenosis. MIS approaches in- 11. Zucherman JF, Hsu KY, Hartjen CA, Wolinsky JP, Witham TF, Bydon A: clude laminotomy, microendoscopic et al: A prospective randomized multi- Epidural steroid injection resulting in laminotomy, and laminoplasty. Fu- center study for the treatment of lumbar epidural hematoma in a patient despite spinal stenosis with the X STOP strict adherence to anticoagulation sion is not indicated except in the interspinous implant: 1-year results. Eur guidelines. 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