You are in: eMedicine Specialties > Plastic Surgery > HAND Hand, Congenital Hand DeformitiesArticle Last Updated: Sep 27, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 8
  Author: D Glynn Bolitho, MD, PhD, FACS, FRCSC, FCS(SA), Associate Clinical Professor, Department of Plastic Surgery, University of California at San Diego; Private Practice, LaJolla, California D Glynn Bolitho is a member of the following medical societies: American College of Surgeons, American Medical Association, American Society for Aesthetic Plastic Surgery, American Society of Maxillofacial Surgeons, American Society of Plastic Surgeons, California Society of Plastic Surgeons, and Royal College of Physicians and Surgeons of Canada Editors: Milton B Armstrong, MD, FACS, Associate Professor of Clinical Surgery, Associate Professor of Clinical Orthopedics, Department of Surgery, University of Miami Miller School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; David W Chang, MD, FACS, Associate Professor, Department of Plastic Surgery, MD Anderson Cancer Center, The University of Texas; Nicolas (Nick) G Slenkovich, MD, Practice Director, Colorado Plastic Surgery Center at Swedish Medical Center; Jorge I de la Torre, MD, FACS, Professor of Surgery and Physical Medicine and Rehabilitation, Residency Program Director, Division of Plastic Surgery, University of Alabama at Birmingham; Director, Center for Advanced Surgical Aesthetics Author and Editor Disclosure Synonyms and related keywords: congenital hand deformity, limb anomaly, apical ectodermal ridge, AER, radial dysplasia, constriction bands, Holt-Oram syndrome, VATER syndrome, Fanconi syndrome, TAR syndrome, Aase syndrome, Nager syndrome, Treacher Collins syndrome, Roberts syndrome, intercalated phocomelia, amelia, phocomelia, acheiria, adactyly, absence of hand, absence of fingers, preaxial deficiency, cleft hand, syndactyly, Apert syndrome, Poland syndrome, acrosyndactyly, symphalangism, radioulnar synostosis, flexion deformities, camptodactyly, arthrogryposis, clinodactyly, delta phalanx, duplication, mirror hand, ulnar dimelia, macrodactyly, arthrogryposis multiplex congenita EMBRYOLOGY AND INCIDENCESection 2 of 8
  Embryology Limb development takes place during the third to eighth weeks of gestation. The limb buds (ie, Wolff crest) appear as swellings on the ventrolateral aspect of the embryo and are condensations of mesenchyme covered with a thick layer of ectoderm termed the apical ectodermal ridge (AER). The AER is a transient structure that is believed to elaborate morphogens that modulate growth patterns. The underlying mesoderm is organized into a posteriorly located zone of polarizing activity (ZPA) and a progress zone (PZ) more anteriorly. Vessels and then nerves subsequently grow into the limb. Mesodermal differentiation into cartilage and muscle begins to occur. The limb begins to pronate, the elbow flexes, and the hand is flexed and the ulnar deviated. Recent work with retinoic acid demonstrates that limb formation can be directed chemically. Inclusion of the ZPA in chick abdomens results in the formation of a normal wing. Apparently, the important factors in the genesis of congenital limb anomalies are the duration of the AER inductive influence, the amount of mesoderm available, and the number of circulating morphogens. Thalidomide results in the formation of abnormal cells within the PZ; if these cells are excised, a normal limb results. Condensation of mesoderm gives rise to cartilage, and ossification follows by the endochondral route. Joint capsules are present prior to the formation of joints. At the point where joint formation is to take place, areas of flattened chondrocytes form dense plates termed interzones, the precursors of articular cartilage. Motion must occur if cavitation is to take place, thus forming the joint. Ossification of the phalanges takes place antenatally, while the carpal bones ossify postnatally. Ossification of the congenitally deformed limb is delayed. By the third week, vessels begin to penetrate the mesodermal mass. Myogenic regions of the limb become vascular, and chondrogenic regions become avascular. Large interosseous and median arteries later give way to the radial and ulnar arteries. Muscle formation is derived from a dorsal (extensor) and ventral (flexor) muscle blastoma. Tendons develop independently of their muscle bellies, only linking later in development. If the adjacent bone is not developed, the tendon attaches to the nearest adjacent structure. The specificity of the nerve-muscle relationship is not known: is it random or specific? Mixed motor and sensory nerves enter the limb as a pioneer growth cone. In general, the anterior division of these nerves supplies the flexors, and the posterior division supplies the extensors. The period of hand differentiation is short, taking place during the fourth to seventh weeks. Incidence A 20-year study in New York gave the incidence of congenital hand deformities as 1 in 626 (Conway, 1956). Regional and ethnic differences exist. Camptodactyly, syndactyly, and polydactyly are the most common abnormalities. Other studies give the incidence as 0.7%. DYSMORPHOLOGYSection 3 of 8
When 3 or more minor anomalies exist in a single patient, the chance of the presence of a major anomaly is 90%. Multiple problems in morphogenesis may be explained in terms of a sequence, which is a simple problem leading to a cascade of subsequent problems. Developmentalists have designated the following 3 types of sequences:
When the cause is unknown, the term malformation is preferred. Approximately one half of cases with multiple anomalies fall into known syndromes. Without specific knowledge, informing parents that the lowest risk is zero and the highest is 25% for each pregnancy is safe. The causes of congenital anomalies can be divided conveniently into genetic, environmental, and unknown causes. Warfarin, phenytoin, and alcohol have been implicated in upper limb anomalies. A minority of congenital anomalies have either a major environmental or a major genetic cause. Syndromes Only 5% of congenital hand anomalies occur as part of a recognized syndrome. Examples include the following:
CLASSIFICATIONSection 4 of 8
The classification proposed by Swanson (1968) has been adopted by the American Society for Surgery of the Hand (ASSH) and the International Federation of Societies for Surgery of the Hand (IFSSH). Atypical cleft hands are difficult to classify, falling into 1 of 3 possible groups. Type I - Failure of formation
Type II - Failure of differentiation
Type III - Duplication
Type IV - Overgrowth
Type V - Undergrowth
Type VI - Constriction band syndromes
Type VII - Generalized anomalies and syndromes
TIMING OF SURGERYSection 5 of 8
Early surgery is defined as that performed within the first 2 years of life. Advantages include the full potential for growth and development, improved scarring, early incorporation of the reconstructed part, anatomic adaptation of the reconstructed part (eg, broadening of pollicized index finger), and reduced psychologic scarring. The only disadvantages of early surgery are increased technical difficulty and possible increased anesthetic risk. Most surgeons perform these operations when the patient is in the second year of life but no later than when the patient enters school. FAILURES OF FORMATIONSection 6 of 8
Transverse arrest at the arm level may be difficult to distinguish from the proximal constriction band syndromes although these are usually bilateral. Treatment is by prosthesis. Intercalated phocomeliaIn amelia, no hand structure is present. In phocomelia, a functional terminal element is always present. The types of phocomelia are (1) those in which the hand attaches to the shoulder (forearm and arm deficient), (2) those in which the forearm attaches to the shoulder (arm deficient), and (3) those in which the hand attaches to the arm (forearm deficient). These patients are best treated by the prosthetist. When the phocomelic hand can reach the mouth, even this is not indicated. Newer myoelectric prostheses allow muscle action to trigger the prosthesis. Occasionally, radial or ulnar deviation of the hand may require centralization. Transverse arrest at forearm levelThis is more common than in the arm. Again, constriction ring syndrome is usually not bilateral, as is this condition. Treatment of these patients is by prosthetics. A seldom performed surgical option is the Krukenberg procedure. This probably is best indicated in bilateral cases when modern prosthetics are not available and in blind patients who depend on the sensory feedback. Most patients find its appearance objectionable and do not use it in public. However, this procedure is compatible with the use of prosthetics. Prosthetic fitting with a mitten is now recommended in patients from age 6 months to allow the child to get accustomed to the use of a prosthesis. This avoids substitution patterns. A hook can be added when the patient is aged 2 years. Children with unilateral deformities tend to discard the prosthesis despite encouragement. Do not make patient acceptance of the prosthesis a focal point of family life. Transverse arrest at the carpal, metacarpal, and phalangeal levelThis refers to acheiria (ie, absence of hand) or adactyly (ie, absence of fingers). These are often difficult to distinguish from constriction band syndromes or as part of a cleft hand. A nail remnant disqualifies patients from this category. When a mobile wrist is present, a palmar plate prosthesis is best. If metacarpal elements are present, the potential is increased greatly, and the objective should be the creation of a basic hand as follows:
Even then, the presence of a unilateral deformity may not require treatment. The surgical options to attain the above are as follows:
The latter is made difficult by the absence of tendons, nerves, and similar structures, except in constriction band syndrome, in which they are invariably present. Preaxial deficiencyThese deficiencies may vary from minor abnormalities of the thenar muscles to complete absence of the preaxial structures. In severe cases, the postaxial structures also are involved. The most common presentation is the short radius, absence of scaphoid and trapezium, and total absence or hypoplasia of the thumb (ie, radial club hand). Elbow stiffness may follow ulnar dislocation due to growth restriction by the fibrous anlage. The deformity has been reproduced by the destruction of the preaxial portion of the limb bud in chickens. It occurs bilaterally as frequently as unilaterally. In the former, it is part of a syndrome in 77% of patients; it is part of a syndrome in 40% of patients when unilateral. The most common associated anomalies are all those mentioned previously (all associated with preaxial malformations). Suspect a limb anomaly in a child that uses two hands to perform a simple task. The thumb may be absent, pouce flotant, or hypoplastic. Digital stiffness may be observed, heralded by the lack of extension creases. The classification is that of O'Rahilly (1951), as follows: Type I - Short radius, no radial bowing or deviation, no treatment Type II - Hypoplastic radius rare, no treatment Type III - Partial absence with fibrous anlage most common; requires centralization procedure Type IV - Total absence second most common; elbow joint usually deficient; soft tissue release and centralization The radial nerve usually ends at the elbow, with the median nerve substituting distally. The radial artery is usually absent. The anlage may restrict growth on the radial side, such that ulnar dislocation occurs at the elbow. Treatment Types I and II do not require treatment. In the severe forms, some patients should not be operated on, including adult patients well adapted to the deformity, those with severe associated malformations, patients with mental retardation such that hand function is immaterial, those with inadequate elbow flexion, and those with tight neurovascular structures. Serial splintage, casts, and passive stretching are useful to maintain soft tissue length. Surgical management falls into the following 4 groups:
Central deficiencyThis deficiency manifests as the absence of digits or metacarpals within the central portion of the hand. The radius and ulna are normal. Barsky classified them as being either typical or atypical. Typical cleft hand Usually the middle or index ray is deficient in a V-shaped deformity. It is often bilateral and may involve the feet. Syndactyly is common. A strong inheritance pattern (dominant or recessive) is present. Often ectodermal deficiencies are associated. Is it due to a central defect in the apical ectodermal ridge (AER)? Treatment should be cautious since an unscarred mobile preoperative hand is difficult to recreate. Syndactyly releases can be performed. Metacarpal transfers may be useful. Avoid procedure that can jeopardize function. Atypical cleft hand The atypical cleft hand also is known as the lobster claw hand. A U-shaped defect involves more than one central ray. The thumb and little finger usually are the best-developed digits on the hand. This deficiency is usually unilateral and a family history seldom is present. Surgical treatment is directed at attainment of the features of a basic hand. Excision of hypoplastic nubbins may be performed. Postaxial deficienciesPostaxial deficiencies are characterized by a much greater degree of variation than those on the preaxial side. They are much more rare, with only 1 postaxial deficiency per every 10 preaxial deficiencies. Most show autosomal dominant (AD) patterns of inheritance. Syndromic associations, by contrast, are rare. Elbow involvement is almost invariable. The wrist is stable and the elbow unstable, while the opposite is generally true of preaxial deformities. Postaxial deficiencies usually are unilateral compared to preaxial deficiencies, which are 100% bilateral. Bayne's classification is similar to that of O'Rahilly's for preaxial defects, except that type IV is humeroulnar synostosis. Again, partial absence is the most common variety (ie, type II). Type I - Deficient ulna, minimal deformity Type II - Partial absence with fibrous anlage radial bowing Type III - Total absence with anlage; radius may be straight Type IV - Humeroradial synostosis; entire limb is shortened Usually absences of metacarpals or digits (90%) are associated, with syndactyly common. Carpal coalitions and thumb anomalies are common. The extent of the hand anomaly bears no correlation with the forearm defect. Only one third of patients demonstrate ulnar deviation at the wrist, and if this is present, it is usually minor. Unlike preaxial anlages, excision probably is warranted only if ulnar deviation is present at the wrist. Radial head dislocation may limit elbow function. Function at the wrist is generally good. The ulnar nerve is usually present. Treatment
FAILURES OF DIFFERENTIATIONSection 7 of 8
SyndactylySyndactyly is one of the most common congenital anomalies in the hand. Failure of programmed cell death in the seventh week of gestation results in this anomaly. The exception is acrosyndactyly, in which refusion of distal digits occurs as part of the constriction ring syndrome. The incidence varies with race but approximates 1 in 2000. It is usually bilateral, and males are affected more commonly than females. Many different types of inheritance patterns are documented (being a common association). The third and then fourth web in the hand and the second web in the foot are most affected. Syndactyly is associated with at least 28 syndromes. Classification Syndactyly is classified according to completeness (complete, incomplete) and the presence of bony union (simple, complex, complicated). Complicated syndactyly refers to any syndactyly in which more than simple side-side bony fusion exists. Associated growth abnormalities with buckling of the bones are common. The normal web ends midway down the proximal phalanx. The skin demonstrates an hourglass configuration, with a 45° slope dorsal to palmar. The fingers are joined by fascial connections across the syndactyly, which link with Cleland ligaments. These are responsible for growth retardation. Phalangeal malformations are common, such as the middle phalanx in clinodactyly and the delta proximal phalanx in the thumb. Symphalangism is common, particularly in syndromic syndactyly. Treatment The goals of surgery are separation of the digits, provision of a lined commissure, and avoidance of scars. Innumerable techniques exist but most embody the following principles:
A dorsal candelabra flap (ie, M-Y flap), combined with square Colville flaps and FTSG to the defects, yields acceptable results (Bloch). This is similar to the technique used by Upton (1988). The pulp adjacent to the nail is best reconstructed by means of the Buck-Gramcko technique. Volar flaps tend to transpose pale skin onto the dorsum, with the attendant cosmetic defect. A dorsal transposition flap (Farkis) alternately may be used to improve the skin defects. An alternate solution is the use of a dorsal rotation flap (Bolitho) for the proximal lateral digital defects. The groin is preferred for FTSG, and the hypothenar eminence is preferred for split-thickness skin graft (STSG). Preputial skin tends to become infected and is hyperpigmented. Tattooing the skin may facilitate skin marking. Techniques that use all of the skin for one finger and graft the other generally yield poor results. The dorsal flap is raised, taking care to preserve the dorsal vein. Neurovascular bundles are identified and preserved, and the fascial bands connecting to Cleland ligaments are divided. The proximal division of the common digital nerve is often the structure limiting the proximal release. The transverse metacarpal ligament rarely may need to be excised. Excess defatting of the flaps to secure closure should be guarded against. The site of skin graft harvest should be lateral to the future hair-bearing area. Medicated tulle gras dressings, bulky fluffed gauze dressings, and an above-elbow plaster of Paris cast is applied (Upton, 1991). Leave one digit visible to enable positional checking within the cast. First web syndactyly occurs in less than 10% of syndactyly incidents. Usually, a single large Z-plasty or a 4-flap Z-plasty is sufficient. The investing fascia of the thenar muscles and the adductor pollicis may require release. In these situations a skin graft is necessary, with K wire fixation to maintain the intraoperative gains. Timing Patterns of prehension are established by the time the individual is aged 1 year. Therefore, all severe abnormalities should be corrected by this time. Correction of less-severe deformities can be deferred to age 12-36 months. Bilateral procedures are best performed early, prior to the time the patient is aged 2-3 years. Complications
Syndactyly-related syndromesApert syndrome Apert syndrome is 1 of 6 acrocephalosyndactyly syndromes (APS). Inheritance is AD. The first ray on all extremities is always deficient. Although mental retardation is not part of the syndrome, at least one half of these patients require assistance at school. This is usually a sequela of raised intracranial pressure (ICP). Intelligence quotient (IQ) is said to be normal if intracranial hypertension is treated aggressively in infancy. Symmetric complex syndactyly is usually present. Dysplasia of the shoulder and elbow joint are common. The hand falls into one of two varieties, flat spadelike hand or constricted, cupped, mitten hand. In the latter, a complex syndactyly exists between the second and fifth rays at the phalangeal level, which allows transverse growth at the metacarpal arch, resulting in the cupped appearance. In the former, no such limitation exists to distal transverse growth. Common to both types of hand are a short radially deviated thumb, complex syndactyly, symphalangism of all 4 digits, and a simple syndactyly of the fourth web. Treatment Correction of the craniofacial deformity usually is accorded first priority. Nevertheless, correction of hand deformities is recommended when the individual is younger than 2 years. Correction certainly should not be deferred on the basis of the child having mental retardation. The principles of treatment are to lengthen and realign the thumb and to separate the digits, beginning with the border digits. The adductor is universally hypertrophic. Resection of the index (I) may be necessary to create a reasonable first web. The resultant 3-fingered hand may be an aesthetic improvement. In the central hand, where anatomic variants abound, releasing only one side at a time is advisable. The thumb may be corrected by a wedge osteotomy and lengthened as necessary. The little (L) finger is often the most normal finger in the hand but is also furthest from the thumb. All major surgery should be complete by the time the patient is of school age. Poland syndrome The hand deformity consists of syndactyly and brachysymphalangism. The first web space invariably is contracted. The sternocostal head of the pectoralis major is the most constant deficit but the pectoralis minor, latissimus dorsi, serratus, and deltoid muscles also may be hypoplastic. Rib cage deficiencies, scoliosis, and dextrocardia have been described. Treatment The lack of skeletal fusions and complicated syndactylies makes the treatment straightforward. In the unusual mitten hand with the thumb in the same plane as the fingers, a rotational osteotomy of the thumb metacarpal may be necessary. Severe forms are rare. Acrosyndactyly Acrosyndactyly is considered to be part of the constriction band syndrome. The band may be present at the birth, and histologic studies have shown this to be chorion. The literal translation means digits fused together in a peak. It supposedly is due to a disruption sequence after the digits have separated, in which they are rejoined by scar tissue. A more fundamental defect is possible because of the high incidence of associated defects. The pattern of limb involvement is completely random. Proximal epithelial-lined sinuses are present and lie more distal than normal commissures, with distal amputation common. Treatment The principle is to perform several smaller procedures rather than one larger one due to the precarious nature of the blood supply. Symphalangism This term was introduced by Cushing and describes the failure of segmentation that results in stiff fingers. This is usually at the proximal interphalangeal (PIP) joint, with metacarpophalangeal (MP) fusion rare. The 3 types of symphalangism are as follows
The joint is represented by a solid cartilaginous bar, which appears as a joint on radiographs. Affected digits are more slender and lack the flexion creases, which is the clue to making the diagnosis. Treatment Treatment is conservative. All attempts at joint reconstruction have met with poor results. Arthrodesis or osteotomy may be useful after the patient reaches maturity. Recommended angles are 20°/30°/40°/50° for the respective digits. Radioulnar synostosis Radioulnar synostosis occurs more commonly than generally is accepted. Longitudinal segmentation of the radius and ulna proceeds from distal to proximal. Failure to differentiate results in synostosis. Of incidence of radioulnar synostosis, 60% are unilateral. This condition presents as a fixed pronation deformity. The radial head is either absent and involved in the synostosis or dislocated. Differentiating this condition from posttraumatic synostosis is important. Treatment Treatment is indicated only for bilateral synostosis or for bilateral synostosis in which the fixed pronation deformity is greater than 45°. Most authors are pessimistic about the results of operative treatment. The treatment of choice is a derotational osteotomy through the synostosis. The major risks are vascular compromise and posterior interosseous nerve palsy. Previously, one arm was placed in slight supination and the other in pronation. Most now recommend neutral and 20° pronation, respectively. Vascular malformations: For information on vascular malformations see Vascular, Capillary Malformations; Vascular, Hemangiomas; Vascular, Lymphatic Malformations; and Vascular, Venous Malformations. Flexion deformities Infants normally hold their thumbs in flexion until aged 3 months, possibly due to the dominance of the flexor innervation prior to that time. Lack of extension (ie, clasped thumb posture) at this time may be due to (1) trigger thumb, (2) congenital absence of the thumb extensors, (3) camptodactyly, or (4) arthrogryposis. Flexion deformities secondary to extensor hypoplasia may be isolated to one finger or involve all fingers. The thumb is involved most commonly, and when the thumb is involved, the I and middle (M) fingers also may be involved. MP extension is lacking, while the interpharyngeal (IP) joints can be extended by the intrinsics. Treatment Passive ROM must be maintained by passive ROM exercises. If an established contracture exists, then joint release is necessary to ensure full ROM prior to tendon transfer. Two options are as follows:
Camptodactyly Camptodactyly is almost exclusive to Caucasians. It presents either in infancy or in adolescence, usually in adolescent girls. It usually is bilateral and affects the L finger most commonly, followed by the ring (R), M, and I fingers. Little functional impairment occurs. Radiographs show a flattening of the condyle of the head of the proximal phalanx. The bony changes are believed to be the result of and not the cause of contractures. Anatomy in camptodactyly
Virtually every structure in the vicinity of the PIP joint has been implicated in the pathogenesis of camptodactyly. Most quote a dynamic imbalance caused by abnormal intrinsic anatomy, with bony and capsular changes secondary. This is most likely to be either an aberrant lumbrical insertion into the flexor digitorum superficialis (FDS) or the digital sheath or an aberrant or tight FDS origin. Other theories are a tight FDS tendon or a palmar plate contracture. Treatment Those presenting in infancy should be treated conservatively by splinting and stretching, although splinting is difficult to maintain. Only one half of adolescent patients improve with stretching. Patients with severe contractures and those in whom conservative management fails are surgical candidates. If the PIP can be extended actively with the wrist and MPs flexed, then FDS release alone is indicated. In general, the principles are as follows:
Permanent correction is unlikely without tendon transfer. In long-standing contractures, the optimal result may be achieved only by arthrodesis in the optimal position or by osteotomy. Clinodactyly Clinodactyly denotes a deviation of a finger as a result of an abnormally shaped middle phalanx. Inward deviation of the L finger is the most common presentation and occurs in as many as 20% of non-Caucasian individuals. The second most common presentation is the proximal phalanx of the thumb. It is almost ubiquitous in widespread congenital anomalies, hence the term "background noise." The degree of deformity correlates directly with the number of associated anomalies. As many as 80% of children with Down syndrome have clinodactyly. Treatment Three options are available, namely opening wedge osteotomy with NVBG, closing wedge osteotomy, or reversed wedge osteotomy. A further option is the excision of bone and replacement by a free fat graft. A closing wedge osteotomy may result in a mallet finger deformity. Delta phalanx This also is termed congenital triangular bone and may refer to a metacarpal. The classic finding is a bone with a continuous C-shaped physis extending the length of the shortened side, like a staple. It usually involves either the middle phalanx of the L finger or the proximal phalanx of the thumb (eg, Apert syndrome). It is part of the deformity in triphalangeal thumb. The clinical presentation thus is clinodactyly but it is due to the delta phalanx. In infancy, it merely can be excised. Later in life, an osteotomy or arthrodesis may be necessary. Excision of the longitudinal physis with fat interposition has been suggested. In the thumb, an opening wedge osteotomy and NVBG, centralization of the flexor and extensor tendons, and reattachment of the intrinsics may be indicated. Duplication Polydactyly is the most common congenital anomaly of the upper limb. In England, it was believed to relate to royalty. Total duplication of the hand and forearm is ulnar dimelia (rare). Preaxial duplication is relatively rare, as is central reduplication, although it often is reported as syndactyly, thus underestimating its incidence. It probably results from increased folding of the AER. The classification of Stelling (1963) and Turek (1967) is as follows: Type I - Soft tissue attachment Type II - Bony articulation Type III - Ray duplication When it occurs in isolation, postaxial polydactyly has a strong inheritance pattern (AD). It is common in African American individuals. Preaxial polydactyly most often presents as triphalangeal thumb. Central duplication may be termed polysyndactyly. Treatment Treatment is primarily surgical. Complex duplications are timed according to most other anomalies, as a compromise between delay on technical grounds and early operation for functional reasons. The principle of surgical treatment is to ablate the most useless digit and to reconstruct its partner. Correction of type III deformities involves a ray resection. Complex central reduplications require individualized treatment. Conversion to a 3-finger hand may be the best option in some patients. Mirror hand (ulnar dimelia) The classic presentation of ulnar dimelia is of duplication of the ulna, with no radius, and 7 or 8 fingers with no thumbs. It may occur in association with fibular dimelia and absence of the tibia. Ulnar dimelia may represent an additional polarizing zone within the limb bud. The postaxial digits usually are more functional. The I finger may not be duplicated (thus 7 fingers) or may be syndactylized to its partner. The fingers are named I, M, R, L and accessory I, M, R, L. Elbow motion usually is limited, with the elbow normally held in extension. Treatment Surgical correction begins proximally with correction of the elbow. Excision of one of the ulnar heads (usually the preaxial) is involved. Elbow flexion may be restored by anterior transposition of the triceps or a Steindler flexorplasty. A derotational osteotomy may be necessary if excessive pronation exists. Wrist extension is restored by tendon transfer (flexor carpi ulnaris [FCU]). Alternately, the wrist is arthrodesed. In the hand, the Entin procedure usually is recommended, which involves resecting the accessory preaxial M and L fingers then using the accessory R digit as a thumb by a modified pollicization procedure. An alternate approach is to use the I finger as part of a conventional pollicization since this may be a more functional digit (postaxial). No tissue should be discarded until it clearly is not necessary for the reconstruction (eg, tendons, skin). Overgrowth (macrodactyly) This condition should be differentiated from others in which an enlargement may occur (ie, vascular malformations, enchondromatoses, osteoid osteoma, fibrous dysplasia, lipomatoses). Macrodactyly is nevertheless a heterogenous group, with 4 of the common presentations as follows:
Treatment The progressive type of macrodactyly is particularly debilitating, functionally and psychologically. Individualization of treatment is particularly important, perhaps more so than in other forms of congenital hand surgery. The objectives are to diminish length and bulk without compromising sensation or vascularity. Surgical options include the following:
Congenital constriction band syndrome This syndrome represents a disruption or deformation sequence subsequent to annular bands of chorionic tissue encircling the limb. It has a low incidence of associated anomalies, normal proximal anatomy, and a sporadic occurrence. Clubfoot is the most common association. Distal fusion of amputated digits, as in acrosyndactyly, may be present. Patterson has set specific diagnostic criteria.
Treatment This is individualized according to the deformity. Options are as follows:
Arthrogryposis multiplex congenita This is a syndrome of unknown etiology that presents at birth and manifests with multiple joint contractures. A decrease in the number of anterior horn cells is observed, with degenerative changes within striated muscles. The joint contractures are probably secondary. Classification into myopathic or neuropathic types is made on the basis of muscle biopsy. Intelligence is normal. It is a diagnosis of exclusion, with marked joint contractures the cardinal sign. The skin is atrophic and waxy in appearance. The hand usually is clasped with a thumb-in-palm deformity. Treatment Splintage and stretching are the hallmarks of treatment. The shoulder and elbow ROM must be established prior to attending to the hand. The most important point is that operation should be avoided in these patients if at all possible. The principles of management are to release joint contractures and to provide appropriate motors for the joints by judicious tendon transfers. REFERENCESSection 8 of 8
Hand, Congenital Hand Deformities excerpt Article Last Updated: Sep 27, 2006 |
