Amniotic Band Syndrome of the Upper Extremity: Diagnosis and Management

Steven L. Moran, MD Abstract Mark Jensen, MD Amniotic band syndrome, a condition involving fetal entrapment César Bravo, MD in strands of amniotic tissue, causes an array of deletions and deformations. Band formation most frequently affects the distal segments, including the hand. Because of the heterogeneous nature of expression of this disease, treatment is individualized. Timing of repair and surgical planning are important in improving functional outcome. In the patient with distal edema and acrosyndactyly, early repair portends better prognosis. Improvements in prenatal diagnosis and fetoscopic surgical technique may eventually allow treatment of amniotic band syndrome in utero.

mniotic band syndrome (ABS) sions, and mutations complex; an- Ais a rare condition in which fe- nular defects; Simonart’s band; tal parts become entangled in amni- congenital ring-constriction; limb- otic membrane, leading to constric- body wall malformation complex; tion, deformation, and deletion. early amnion rupture sequence; in- Resulting defects from constricting trauterine or fetal amputation; con- Dr. Moran is Associate Professor, bands range in severity from mild striction band syndrome; Streeter’s Orthopaedic and Plastic Surgery, Mayo constriction to complete limb dele- dysplasia2) attests to the difficulty Clinic College of Medicine, Rochester, tion, anencephaly, and fetal demise. physicians have had in determining MN. Dr. Jensen is Resident, General Amniotic bands most commonly af- its etiology. Surgery, Mayo Clinic. Dr. Bravo is Co- fect the extremities, with a predilec- ABS was first defined based on Director, Microvascular, Hand and tion for the distal segments (Figure the presence of constrictive tissue Upper Extremity Section, Carilion Clinic 1). Deformations affecting the upper bands, amniotic adhesions, and Bone and Joint Center, Roanoke, VA. extremity can be disabling and, be- more complex patterns of anoma- None of the following authors or the cause of the unique presentation in lies, designated as the limb-body departments with which they are each individual, pose a treatment wall complex.3-5 Streeter suggested affiliated has received anything of value challenge. that an intrinsic defect in the subcu- from or owns stock in a commercial taneous germplasm resulted in fo- company or institution related directly or cal mesenchymal hypoplasia, tissue indirectly to the subject of this article: Etiology, Embryology, 1 and Demographics loss, and scarring. The proposed Dr. Moran, Dr. Jensen, and Dr. Bravo. mechanism was thought to be simi- Reprint requests: Dr. Moran, Mayo The earliest recorded account of ABS lar to that involved in the develop- Clinic, Mayo 1244 West, 200 First dates to Hippocrates, who made ref- ment of normal skin folds, which ap- Street SW, Rochester, MN 55905. erence to a syndrome of amputation pear very similar histologically. or band formation caused by fetal In contrast, the extrinsic theory J Am Acad Orthop Surg 2007;15:397- membranes encircling the extremi- proposed that the entanglement of fe- 407 ties or digits.1 The number of syn- tal parts by bands of amniotic tissue Copyright 2007 by the American onyms associated with ABS (annular caused deformation. Histologic evi- Academy of Orthopaedic Surgeons. bands; amniotic disruption se- dence of amniotic tissue within con- quence; amniotic deformity, adhe- striction grooves provided support for

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Figure 1 genic process. The upper limb buds appear as small bulges at 24 days, with proliferation of an ectodermal ridge overlying mesodermal tissue. Upper limb morphogenesis occurs in weeks 4 through 8; lower extremity development occurs in weeks 5 through 9. By day 33, the hand plate is visible at the end of the limb bud. Digital rays appear during week 6 on the upper extremity and week 7 on the lower extremity. A process of programmed cell death sculpts these rays into fingers and toes. This process is complete by the end of week 8. During week 5, skeletal elements develop from mesodermal condensa- tions that appear along the long axis of the limb bud. Higginbottom et al12 showed that fetal development and timing of amniotic entrapment greatly altered the expression of ABS. Rupture before 45 days’ gestation led to a higher rate of central abnormalities, including severe cen- Frequency of involvement of the extremities (n = 364) (A) and digits (n = 462) tral nervous system malformations, (B) in amniotic band syndrome.6 (Reproduced with permission from the Mayo truncal defects, and abortion. Later Foundation.) rupture more frequently entrapped the limbs and spared the central structures.12 this idea. Case reports of formed, am- ner, mesenchymal, and outer layers. Protruding fetal structures are putated extremities within the amni- The inner and mesenchymal layers more vulnerable and much more otic cavity suggested that the syn- play an important role in secreting likely to be entrapped than are oth- drome was a deformation rather than collagen, fibronectin, and lamin to er anatomic structures. Numerous a true malformation.1,6 Houben7 and provide a strong elastic and tensile observational studies have indicated Kino8 duplicated similar limb dele- layer. The outer layer, also known as that involvement is more common tions and syndactyly by performing the spongy layer, is adjacent to the in the upper extremities, with a pre- early amniocentesis on rat embryos. chorion; it can swell to accommodate dilection for the distal segments of These authors suggested that extrin- sliding of the amnion across the the hand.1,8,13 Middle digits are most sic forces on the limb buds led to chorion. The membranes are seen on commonly involved, with relative hemorrhage of the distal marginal ultrasound as two separate and dis- sparing of the thumb. This pattern blood sinuses, which in turn led to tinct entities until approximately correlates with fetal positioning, hematoma formation, scarring, dele- 3 months’ gestation, when the with either outstretched fingers or a tion, and acrosyndactyly. Medical chorion and amnion fuse. Defects or clenched thumb in the palm, pro- imaging technology has confirmed tears of the inner membrane can lead tected by the other digits.1,8,13 the extrinsic theory by demonstrat- to fetal entrapment. Transient oligo- No two cases of constriction ing the presence of constricting bands hydramnios caused by the loss of am- bands are identical. Fetal banding of fetal membranes that lead to niotic fluid also may contribute to gives rise to varying degrees of de- deformation.9-11 deformation of early limb buds, in- fects, ranging from skin dimpling and Fetal membranes are composed of cluding the occurrence of clubfoot soft-tissue constriction rings to com- two distinct layers: the amnion and deformity.8 plete deletion (Figure 2). Soft-tissue the chorion. The inner amnion, The stage of limb development at strictures can disrupt neurovascular which provides the majority of ten- time of entrapment determines the bundles, resulting in distal anes- sile strength, is composed of the in- physical appearance of the patho- thesia, peripheral nerve palsy, vascu-

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Figure 2

Amniotic band syndrome can present with a spectrum of deformity. A, Mild involvement may present with only skin dimpling or banding. B, A 4-year-old with nerve compression and lymphedema caused by more severe circumferential banding. C, The hand of the same child as in panel A, demonstrating evidence of a noteworthy deformity, with truncation of finger length and evidence of acrosyndactyly.

lar insufficiency, venous congestion, with scar formation and ingrowth of calcaneovalgus, pes valgo planus, and lymphedema (Figure 2,B).14 ectoderm. The mechanism may, in congenital hip dislocation, and con- Finger involvement may result in fact, represent a composite of these genital vertical talus.20,21 Clubfoot de- acrosyndactyly, which is character- theories. formity associated with ABS is often ized by a constriction ring around The incidence of ABS has been re- more challenging to treat than its id- adjacent digits, with distal soft- ported at 1:1,200 births, with equal iopathic counterpart because of rigid tissue webbing and epithelial sinus expression in males and females.5 No equinovarus deformity and frequent tracts at the base of the proximal autosomal inheritance pattern has deep distal circumferential banding phalanx (Figure 3). Complete digit been identified, nor has a connection of the skin and soft tissue.22 Other separation proximal to the band is been made to any infectious agent.1,16 anomalies, such as cleft lip, cleft pal- common15 (Figure 3, A). The mecha- Some studies have shown a racial ate, hemangioma, meningoceles, ab- nism of acrosyndactyly is not fully predisposition, but these findings dominal wall defects, and skin tags understood, but several theories may be influenced by selection or re- have been noted to occur in associa- have been postulated. Some investi- ferral bias rather than evidence of a tion with ABS.13 Associated hand gators have suggested that early true predisposition.17-19 An associa- anomalies include syndactyly, acro- bands block programmed cell death tion with oligohydramnios may ex- syndactyly, digital hypoplasia, sym- and separation of the distal digital plain the increased frequency of club- brachydactyly, and campodactyly; rays.8,11,12 Alternatively, constriction foot deformity; however, this finding pseudosyndactyly is the most com- rings may cause distal hemorrhage is not ubiquitous. Researchers have mon.23 of fragile vessels, leading to hemato- postulated that early, transient oligo- ma formation, scarring, and fusion hydramnios at the time of amniotic Differential Diagnosis of distal digits.8 Patterson16 argued disruption is most likely causative.7 that constriction bands around Other anomalies that may be associ- The differential diagnosis of ABS in- formed fingers may cause ulceration, ated with oligohydramnios include cludes vasculocutaneous catastro-

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Figure 3

A, Acrosyndactyly of the index and long finger. Note the amputation of the distal phalanx of the ring finger and banding over the small finger. B and C, Severe acrosyndactyly with a probe in the sinus tract present at the base of the fingers.

Figure 4

Neonatal gangrene in the upper (A) and lower (B) extremities. Telltale findings include the presence of skin slough and ischemic skin changes throughout the forearm.

phe of the newborn, brachysyndac- bands protrude into the lumen of the the perinatal period. An altered fi- tyly, and transverse growth arrest. amniotic cavity but do not adhere to brinolytic system, high plasminogen Several features can help to distin- the fetus and do not cause ABS. Pa- levels, and antiplasmin inhibitors guish ABS, including the presence of tient history, ultrasound, and mag- have been implicated.17,25 The pa- constriction bands in alternative ar- netic resonance imaging are useful tient with vasculocutaneous catas- eas and the development of normal for diagnosis.24 trophe may present with a swollen structures proximal to the band. In Vasculocutaneous catastrophe of forearm, contracted finger, or digital utero, amniotic bands should be dis- the newborn also has been referred necrosis (Figure 4). Skin lesions are tinguished from amniotic sheets and to as neonatal gangrene and neonatal frequently present on the day of de- uterine synechia, which are adhe- Volkmann contracture. The etiology livery. These lesions are described as sions caused by prior instrumenta- is not completely understood, but bullous or ulcerative and are local- tion, such as curettage, Caesarean the condition seems to be related to ized to the dorsum of the forearm, section, and myomectomy. These ischemia from a vascular insult in wrist, and hand, with associated dis-

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For personal use only, do not distribute © 2019 American Academy of Orthopaedic Surgeons Steven L. Moran, MD, et al tal edema. Early fasciotomy for asso- Figure 5 ciated compartment syndrome can minimize adverse sequellae.26 Symbrachydactyly usually affects the entire upper limb; the patient typically has a small hand with simple syndactyly (Figure 5). Bi- lateral cases are rare, with reported incidence ranging from 1.6% to 10%.1,20,27 The presence of distal phalanges with fingernails repre- sents ectodermal tissue not de- stroyed by the mesodermal event. Symbrachydactyly, which may be familial, has been associated with Poland’s syndrome. Transverse growth arrest, which constitutes a failure of formation, is occasionally seen in association 28 with ABS. The deformities in this A patient with symbrachydactyly who has characteristic preservation of nails without clinical scenario are usually bilater- evidence of acrosyndactyly. al and may have an autosomal reces- sive inheritance pattern with variable expression.23 Overgrowth and with well-formed webs of the prop- perature gradients have been mea- symptomatic diaphyseal amputation er depth; type II, the tips of the dig- sured across constricting rings.6 is infrequently seen.27,29 The most its are joined, but web formation is Forearm constriction may cause pal- common site of amputation is at the not complete; and type III, joined sy of the median and ulnar nerves, proximal third of the forearm as the tips, sinus tracts between digits, and with resulting sensory defects and, result of disruption of the apical ec- absent webs.29 possibly, permanent nerve dam- todermal ridge. age.14,18,31 Distal lymphedema is Clinical Presentation in common, with histologically dilated Classification the Hand lymphatics and wide open tissue spaces filled with excess fluid. There are several proposed classifi- In the hand, clinical presentation of Acrosyndactyly (ie, pseudosyndacty- cation systems for ABS, based on lo- ABS can vary from slight indenta- ly) is common in affected digits. Al- cation and severity of disease. The tions on the affected part to distal though it may affect all fingers, the Ossipoff and Hall classification is atrophy, lymphedema, acrosyndac- index, middle, and ring fingers are based on involvement of three major tyly, and amputation.1 Histological- most frequently involved.17 anatomic areas: limb, visceral, and ly, mild constriction bands resemble craniofacial. Swanson28 developed a naturally occurring skin creases. Management subclassification of upper extremity The dermis is thinned with atrophy ABS. The most widely used classifi- of the underlying subcutaneous tis- Management, which must be indi- cation system, described by Patter- sue. More severe constriction bands vidualized, ranges from cosmetic re- son, is based on severity of the cause fibrous scar formation that can pair to emergent limb-sparing band syndrome, ranging from simple lead to severe vascular, lymphatic, release. Z-plasty, W-plasty, and V-Y constriction rings, to constriction and neural damage. Symptoms may flaps are the mainstay for release of rings associated with deformity of progress as the child grows. Some pa- superficial and deep rings in the pres- the distal part, with or without tients present with ulceration of the ence of good distal function. Deep lymphedema (Figure 2, B), to con- base of the constriction ring or with rings with neurovascular compro- striction rings associated with firm skin protuberances on the dor- mise may require special attention acrosyndactyly (Figure 3), to intra- sum of the fingers.15,30 Neurovascu- to neurovascular reconstruction. Is- uterine amputation.16 Patterson di- lar compromise leads to ischemia, chemia, which may lead to osteomy- vided constriction rings associated nerve injury, and distal atrophy. Nail elitis, may necessitate amputation.21 with acrosyndactyly into three bed changes are common, with fre- Finger and toe transfer, augmenta- types: type I, conjoined fingertips quent absence of nail growth.14 Tem- tion, lengthening procedures, bone

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For personal use only, do not distribute © 2019 American Academy of Orthopaedic Surgeons Amniotic Band Syndrome of the Upper Extremity: Diagnosis and Management grafting, and composite toe transfer superficial bands and staged release are preserved, along with the neu- have been used to restore function in for deep bands. rovascular bundle, thus helping to patients with amputation.32,33 In the prevent postoperative venous con- patient with acrosyndactyly, syndac- Surgical Considerations gestion. In the case of deep dorsal tylized digits are separated and web grooves, there is often a paucity of spaces deepened to enhance indepen- Preoperative radiographs, nerve ve- dorsal veins, and a staged release dent finger function. locity studies, and vascular mapping should be performed. The skin is may aid in surgical planning and al- closed after the subcutaneous fat is Timing of Repair low for a more reliable prediction of approximated with fine absorbable postoperative outcome. Nerve veloc- suture. The skin suture line should Timing of repair is dictated by disease ity studies may be indicated for the be staggered from the adipose suture severity and predicted skeletal patient who presents with distal line (Figure 6, A-E). growth. Cosmetic repair of shallow neuralgia, paresthesia, or paralysis. Skin approximation on the pal- constriction rings that present with- For the patient with irreversible mar surface usually does not require out distal edema may be done elec- nerve damage, a thorough discussion substantial skin advancement and tively.1 Release of bands associated of treatment and expected function- may be closed with simple reapprox- with severe distal edema should be al outcomes with the parents is indi- imation. Dorsal digital deformities performed within the first few days cated.14 frequently require Z-plasty, which is after birth.30,34 Left untreated, chronic best placed on the side of the finger stretching and fibrosis of the tissue Simple Constriction in the midlateral line to minimize develops, resulting in poor resolution Rings visible scarring. After mobilizing the of edema. In the patient with acrosyn- subcutaneous tissue, the excess skin dactyly, repair in the first 3 to 6 Treatment may not be necessary for on the proximal flap is advanced dis- months allows the best chance for superficial constriction rings be- tally and palmarly, starting at the proper longitudinal bone growth. This cause they may become less appar- dorsal midline. Occasionally, a broad is particularly important when the ent as the infant fat is absorbed from constriction band necessitates a joined fingers are of different lengths. the hands during growth. Grooves cross-finger flap to replace the defi- Cerebral pattern hand use after sep- can be excised with mobilization of cient area. Bands in series are re- aration of digits is optimized when re- the adipose tissue and reapproxima- paired in stages; the more distal band pair is performed before age 1 year.30 tion of skin via Z-plasty. Simple is corrected first.6,38 excision without Z-plasty leaves a Constriction bands with consid- Single Versus Staged circular scar that may contract, pro- erable distal lymphedema, cyanosis, Release ducing a more noticeable defect than and circulatory embarrassment may was present before repair.6 progress quickly to ulceration or in- No clear guidelines have been estab- We prefer to use the Upton tech- fection. In such patients, urgent re- lished regarding the amount of tissue nique when repairing moderate to lease of the ring is required. The to release and reconstruct at one time. severe rings presenting with or with- surgical principles are the same as For digits that are circumferentially out edema.38 Before incision, one above, with staged excision of the involved, release of the entire digit sidewall of the band is marked with band. After the first operation, may be done in a single opera- ink and pressed against its partner to lymphedema decreases as the lymph tion.1,31,35-37 Digital endosteal blood create a superimposed image. These channels are restored. The second supply and myocutaneous arteries are markings help guide skin resection. release can be performed 2 to 3 adequate for tissue viability distal to All ring tissue is considered scar and months after the first. The surgeon the constricting band.1,31,35-37 Veno- should be removed. Skin flaps are must inform the parents that some congestion that occurs after single- then mobilized proximally and dis- residual edema may persist.6 Postop- stage release, which is most problem- tally. Excess skin is left proximally erative extremity wrapping with an atic with deep bands, is treated with until skin closure. The adipose tis- elastic circumferential bandage or leech therapy or suture release. The sue is then mobilized below the der- compressive sleeve facilitates edema rationale for the staged procedure is mis and above the muscles or ten- resolution. that once cutaneous circulation has dons. The proximal and distal been reestablished across the scar, the adipose tissue is mobilized and ap- Separation of Digits and remaining 50% of the band can be re- proximated over the site of the annu- Web Reconstruction moved safely. Six to 12 weeks be- lar groove to correct the contour de- tween procedures is advised.1 Most formity. During dissection, at least Treatment of acrosyndactyly varies experts recommend single release for one or two large subcutaneous veins depending on the extent of fusion

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Figure 6

Surgical treatment of digital constriction rings. A, Dorsal view of a constriction ring demonstrating the area to be excised. The ring is excised in its entirety. B and C, Surgical correction begins with excision of all skin in the side walls and debulking of dorsal excess adipose tissue. D, Flaps are mobilized proximally and distally as needed to correct the contour deformity. E, Skin and subcutaneous closures are preferably staggered, and Z-plasties are positioned along the side of the digit, with straight line closure dorsally to minimize visible scarring. F, The constriction ring has been excised, and a dorsal bridging vein has been preserved. G, The appearance of the finger at time of closure. (Reproduced with permission from the Mayo Foundation.) and associated band deformities. Surgical approach is guided by sever- cal goal is early release to allow par- Narrow skin bridges can be cut or ity of disease. Walsh39 proposed a allel growth of the fingers without ar- tied off in the neonatal unit. Deep helpful distinction of groups into ticular deformities. Surgery should be bands with severe syndactyly pose mild, moderate, and severe. performed by age 6 months, or as a considerable challenge. Surgical The patient with mild acrosyndac- soon as possible for the patient who planning should be guided by the tyly presents with three phalanges presents at an older age. Split- dictum that the number of fingers is and two interphalangeal joints in the thickness skin grafts are used to not as important as their spacing, affected digits, typically with long cover the interdigital skin defect. To length, bulk, stability, and control. clefts between the fingers. The surgi- provide increased function, subse-

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For personal use only, do not distribute © 2019 American Academy of Orthopaedic Surgeons Amniotic Band Syndrome of the Upper Extremity: Diagnosis and Management quent surgery may be performed to Acrosyndactyly caused by con- Web space deepening (ie, phalan- deepen the web space.6 striction bands can be challenging to gization) is effective with thumb in- The patient with moderate repair because of the associated rings volvement. This deepening, as well acrosyndactyly presents with two and distal deformity. Each case is as syndactyly release, allows for op- phalanges and one interphalangeal unique and must be individualized. position. For the patient presenting joint. Fusion of the digits will cause In general, the fingers are separated with cleft hand, the rudimentary considerable articular defects, which using carefully planned Z-plasty digits are removed, and the first web must be released early to prevent skin flaps, and a broad commissural space is created or improved. Stabili- permanent damage. Distortion of the space is created based on a dorsal zation of boneless digital stumps can distal fingertips is the greatest chal- skin flap. The sinus tract is excised be accomplished with toe phalangeal lenge. It may be difficult to deter- and may be used as a skin graft. This transplants. mine which fingertip goes to which tract is generally not well suited for Monodactylous ABS is most com- finger. Preservation of the distal tips a commissural space because of its monly treated with vascularized toe is preferred over amputation because distal location and narrow space.40 transfer. This is done primarily at the tips may contain phalangeal buds Skin flaps are mobilized, and the tis- the ulnar side to provide pincer ac- that can be associated with articular sue is defatted. Fingers are separated tion. Limited mobility of the trans- spaces. In many patients, increased proximally to the transverse inter- ferred digit allows the patient to use function can be gained by deepening metacarpal ligament.30 Blood vessels it as an ulnar post. When the thumb the commissures. and nerves are preserved, and the is the only digit involved, index fin- The patient with severe acrosyn- skin flaps are sewn down, with a ger pollicization or intercalary bone dactyly has only stubby fingers, with full-thickness skin graft covering the grafting with or without distraction one phalanx and no interphalangeal bare area. The hand is dressed and osteogenesis can be done.15 joints. The heterogeneity of the dis- inspected at 2 weeks postoperative- Peromelic aplasia is an uncom- ease makes these cases very chal- ly. Further dressing for 7 to 10 days mon condition characterized by ab- lenging. The surgeon frequently is is followed by removal and complete sent digits with intact metacarpals. faced with a bulbous portion and mobilization of the hand. When graft Grip is possible only when the basal deep constriction rings. Fingers are failure occurs, the area should be re- thumb joint is present. Some au- short and often distorted. The surgi- grafted to avoid scars because these thors recommend thumb lengthen- cal goal in these cases is early sepa- tend to tether the joint as the patient ing procedures using toe phalanx ration combined with commissural grows. Patients should be followed transfer.42 Dual toe transfer may be deepening. Further revision and because they frequently require preferable in some instances. The deepening may be performed at a lat- commissural revision in adoles- surgical goal is to provide a function- er date to optimize function. Digit cence6 (Figure 7). al pincer group.33 Prosthetics have lengthening procedures may be con- been used as an alternative to toe sidered in patients with severe Digital Aplasia transfer. acrosyndactyly. Clinical presentations of digital apla- Treatment Recommendations for Surgical Technique sia include thumb aplasia and cleft hand, as well as the monodactylous Digital Aplasia Numerous techniques have been de- (one remaining digit) and peromelic The minimal requirement for re- scribed for separation of syndactyly, (no remaining digits but intact meta- construction of a functional hand is but all share general principles as carpals) types. Many procedures have the presence of at least two digits presented by Flatt:6 (1) create a broad been described, including on-top that can oppose with some power. commissural space from a local (usu- plasty, toe phalanx transplantation, One digit should be capable of mo- ally dorsal) skin flap, (2) defat fingers metacarpal distraction, web space tion so that it can grasp objects. The to aid in closure, (3) close the sides of deepening, and thumb lengthening. other digit need only act as a stable the fingers with zigzag local flaps, (4) On-top plasty is used for the defi- post against which the movable cover bare areas with full-thickness cient thumb, or index or long finger. digit can pinch. To allow for prehen- skin grafts, (5) correct skeletal abnor- The distal end of the index or ring sile movements, the digits require malities, (6) release only one side of finger metacarpal is transposed with some form of cleft to divide them, a finger at a time, (7) use magnifica- the proximal phalanx on a neurovas- which allows for the accommoda- tion and meticulous technique, and cular pedicle.30,41 This digital trans- tion of objects. The digits must be (8) use postoperative dressings de- fer lengthens the digit and deepens sensate and pain free; otherwise, signed specifically for the pediatric the web space when combined with they will provide little benefit over a patient to protect the repair. index metacarpal shortening. prosthesis.

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Figure 7

A, A 2-year-old with evidence of amniotic band syndrome and a complete simple syndactyly involving the long and ring fingers. B and C, Dorsal and volar skin flaps are designed to maximize the web space and limit the amount of supplemental full- thickness graft required for complete closure. D and E, Photographs taken 4 weeks following excision of amniotic bands and web space deepening. F and G, Photographs taken at 5-month follow-up demonstrating good cosmetic and functional results.

In most patients with ABS, the the function of the remaining fin- the best means of recreating a sen- thumb can be preserved; thus, treat- gers. In the absence of a thumb, a sate, mobile thumb that can grow ment is often directed at improving vascularized toe transfer provides with the patient. In ABS, vascular

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For personal use only, do not distribute © 2019 American Academy of Orthopaedic Surgeons Amniotic Band Syndrome of the Upper Extremity: Diagnosis and Management and neural structures are usually of Prenatal Management heterogeneous expression, with fre- normal caliber proximal to the con- quent lymphedema, neurovascular stricting band, making microvascu- Advances in prenatal diagnosis and compromise, and acrosyndactyly. lar reconstruction possible. fetoscopic techniques have made Management of ABS is focused on Reconstruction of the thumb and prenatal treatment of ABS within increasing function and develop- a single digit will enable some pre- the realm of possibility. Several in- ment while providing a more aes- hensile grasp. For optimal function, vestigators have reported on feto- thetic appearance. Ideally, release however, an additional digit should scopic release of tight amniotic should be performed within the first 10,11 be reconstructed. The preservation bands, with variable results. In year of life to optimize proper neuro- or reconstruction of the thumb and one case, difficulty with amniotic logic and skeletal development. Par- bleeding necessitated fetal abortion. two digits allows for the possibility ents and children must have realistic In another report, two patients un- of chuck pinch and improved subter- expectations and must understand derwent fetoscopic Nd-YAG laser re- minal pinch. The presence of a third that repeat surgery may be neces- lease of limb-threatening bands from digit will confer lateral stability in sary. Research on prenatal diagnosis two hands and one leg in each pa- power pinch. A third digit also al- and treatment is ongoing. tient.10,11 Preoperative Doppler ultra- lows the patients to perform hook sound studies revealed loss of blood References grip and power grasp. Span grasp is flow, which was restored after band also made possible because the func- release. Following delivery of the Citation numbers printed in bold tional palmar space is increased, al- first patient, one hand was severely type indicate references published lowing for grasp of larger objects. For malformed and was amputated to fit within the past 5 years. digital loss at the level of the proxi- a prosthetic. One leg of the same pa- mal phalanx or the metacarpopha- 1. Wiedrich TA: Congenital constriction tient was salvaged, with only a sur- band syndrome. Hand Clin 1998;14: langeal joint, a free second toe trans- face impression of the band evident 29-38. fer often provides the best long-term at birth. An arm was salvaged in 2. Light TR: Growth and development of longitudinal growth and recovery of the second patient, but persistent the hand, in Carter PR (ed): Recon- interphalangeal motion. lymphedema necessitated postpar- struction of the Child’s Hand. Phila- delphia, PA: Lea and Febiger, 1991, p tum band release. 122. These cases represent an exciting Complications 3. Torpin R: Amniochorionic mesoblas- advancement in prenatal diagnosis tic fibrous strings and amnionic Complications from repair of ABS and treatment; however, preterm bands: Associated constricting fetal premature rupture of membranes, malformations or fetal death. Am J include infection, hematoma, flap Obstet Gynecol 1965;91:65-75. necrosis, graft necrosis, and distal chorioamnionitis, bleeding, preterm 4. Bamforth JS: Amniotic band se- circulatory failure. Use of surgical labor, and fetal loss remain real con- quence: Streeter hypothesis revisited. magnification to preserve vessels cerns. Further, prenatal screening ul- Birth Defects Orig Artic Ser 1993;29: 279-289. and meticulous surgical technique trasounds are frequently performed during the second trimester, which 5. Moerman P, Fryns JP, Vandenberghe are needed to minimize vascular K, Lauweryns JM: Constrictive amni- is too late for intervention in most compromise. Hematoma is usually otic bands, amniotic adhesions, and patients. Much more research is re- prevented with strict hemostasis, limb-body wall complex: Discrete dis- quired to advance the technology ruption sequences with pathogenetic carefully applied postoperative used in prenatal management of overlap. Am J Med Genet 1992;42: dressing, splinting of the hand, and ABS.9-11 470-479. judicious use of drains. Once the 6. Flatt AE: Constriction ring syndrome, flaps have been dissected, the tour- in The Care of Congenital Hand Summary Anomalies. St. Louis, MO: CV Mos- niquet may be released to obtain by, 1977, p 214. hemostasis before closure. Flaps ABS is a nonfamilial condition 7. Houben JJ: Immediate and delayed ef- should be closed in a tension- caused by aberrant strands of amni- fects of oligohydramnios on limb de- free manner, and dressings lightly velopment in the rat: Chronology and otic membrane exerting strangulat- specificity. Teratology 1984;30:403- placed. Minimizing excessive move- ing forces on the developing fetus. 411. ment of the reconstructed part re- Its clinical presentation is varied, 8. Kino Y: Clinical and experimental sults in a lower incidence of flap or with frequent expression in the up- studies of the congenital constriction graft necrosis. Preventive measures per extremity. Deformities range in band syndrome, with an emphasis on its etiology. J Bone Joint Surg Am should be taken to minimize the severity from mild contour deformi- 1975;57:636-643. aforementioned common complica- ties to severely debilitating limb 9. Sentilhes L, Verspyck E, Eurin D, et al: tions.38,43 malformations. The condition has a Favourable outcome of a tight con-

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striction band secondary to amniotic tion band syndrome. J Pediatr fers in the reconstruction of the band syndrome. Prenat Diagn 2004; Orthop 1988;8:461-466. aphalangic hand. J Hand Surg [Am] 24:198-201. 21. Woods T, Romansky N: Congenital 1982;7:454-459. 10. Quintero RA, Morales WJ, Phillips J, constriction band syndrome. JAm 33. Gilbert A: Toe transfers for congenital Kalter CS, Angel JL: In utero lysis of Podiatr Med Assoc 1995;85:310-314. hand defects. J Hand Surg [Am] 1982; amniotic bands. Ultrasound Obstet 22. Allington NJ, Kumar SJ, Guille JT: 7:118-124. Gynecol 1997;10:316-320. Clubfeet associated with congenital 34. Iwasawa M, Takahashi N, Matsuo K, 11. Crombleholme TM, Dirkes K, Whit- constriction bands of the ipsilateral Hirose T, Otagiri T: Congenital ring J Pediatr Orthop ney TM, Alman B, Garmel S, Connel- lower extremity. constriction syndrome: Intervention ly RJ: Amniotic band syndrome in fe- 1995;15:599-603. at seven days. A case report. Eur J tal lambs: I. Fetoscopic release and 23. Temtamy SA, McKusick VA: The ge- Plast Surg 1987;9:176-178. morphometric outcome. J Pediatr netics of hand malformations. Birth 35. Daniel RK, Williams HB: The free Surg 1995;30:974-978. Defects Orig Artic Ser 1978;14:1- transfer of skin flaps by microvascular 12. Higginbottom MC, Jones KL, Hall BD, 619. Smith DW: The amniotic band dis- 24. Kato K, Shiozawa T, Ashida T, Unno anastomoses: An experimental study ruption complex: Timing of amniotic N, Konishi I: Prenatal diagnosis of and a reappraisal. Plast Reconstr rupture and variable spectra of conse- amniotic sheets by magnetic reso- Surg 1973;52:16-31. quent defects. J Pediatr 1979;95:544- nance imaging. Am J Obstet Gynecol 36. Hall EJ, Johnson-Giebink R, Vasconez 549. 2005;193:881-884. LO: Management of the ring constric- 13. Tada K, Yonenobu K, Swanson AB: 25. Blank JE, Dormans JP, Davidson RS: tion syndrome: A reappraisal. Plast Congenital constriction band syn- Perinatal limb ischemia: Orthopaedic Reconstr Surg 1982;69:532-536. drome. J Pediatr Orthop 1984;4:726- implications. J Pediatr Orthop 1996; 37. Muguti GI: The amniotic band syn- 730. 16:90-96. drome: Single-stage correction. Br J 14. Uchida Y, Sugioka Y: Peripheral nerve 26. Ragland R III, Moukoko D, Ezaki M, Plast Surg 1990;43:706-708. palsy associated with congenital con- Carter PR, Mills J: Forearm compart- 38. Upton J, Tan C: Correction of constriction band syndrome. J Hand ment syndrome in the newborn: Re- striction rings. J Hand Surg [Am] Surg [Br] 1991;16:109-112. port of 24 cases. J Hand Surg [Am] 1991;16:947-953. 15. Kay SP: Absence of fingers, in Green 2005;30:997-1003. 39. Walsh RJ: Acrosyndactyly: A study of DP, Pederson WC, Wolfe SW (eds): 27. Burgess RC: Brachydactyly in 27 patients. Clin Orthop Relat Res Green’s Operative Hand Surgery J Hand Surg [Am] . acrosyndactyly. 1970;71:99-110. Philadelphia, PA: Elsevier, 2005, pp 1991;16:125-126. 40. Miura T: Congenital constriction 1415-1417. 28. Swanson AB: A classification for con- band syndrome. J Hand Surg [Am] 16. Patterson TJ: Congenital ring- genital limb malformations. J Hand 1984;9:82-88. constriction. Br J Plast Surg 1961;14: Surg [Am] 1976;1:8-22. 41. Keller H, Neuhauser G, Durkin- 1-31. 29. Light TR, Ogden JA: Congenital con- 17. Foulkes GD, Reinker K: Congenital striction band syndrome: Pathophysi- Stamm MV, Kaveggia EG, Schaaff A, constriction band syndrome: A ology and treatment. Yale J Biol Med Sitzmann F: “ADAM complex” (am- seventy-year experience. J Pediatr 1993;66:143-155. niotic deformity, adhesions, mutila- Orthop 1994;14:242-248. 30. Emmett AJ: The ring constriction tions): A pattern of craniofacial and 18. Moses JM, Flatt AE, Cooper RR: An- syndrome. Handchir Mikrochir Plast limb defects. Am J Med Genet 1978; nular constriction bands. J Bone Joint Chir 1992;24:3-15. 2:81-98. Surg Am 1979;61:562-565. 31. Di Meo L, Mercer DH: Single-stage 42. Buck-Gramcko D: The role of non- 19. Garza A, Cordero JF, Mulinare J: Epi- correction of constriction ring syn- vascularized toe phalanx transplan- demiology of the early amnion rup- drome. Ann Plast Surg 1987;19:469- tation. Hand Clin 1990;6:643-659. ture spectrum of defects. Am J Dis 474. 43. Visuthikosol V, Hompuem T: Con- Child 1988;142:541-544. 32. Goldberg NH, Watson HK: Compos- striction band syndrome. Ann Plast 20. Askins G, Ger E: Congenital constric- ite toe (phalanx and epiphysis) trans- Surg 1988;21:489-495.

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