A 3-year-old girl with constriction band syndrome has absence of functional fingers on the dominant right hand. The dominant thumb is completely spared. Which of the following is most appropriate for correction of this deformity?
(A) Intensive occupational therapy
(B) Use of digital prostheses
(C) Metacarpal lengthening
(D) Reconstruction with a radial forearm osteocutaneous flap
(E) Toe-to-hand autotransplantation
The correct response is Option E.

Reconstruction should be considered in a child who has partial or complete absence of function of the thumb or one or more fingers. Absence of functional fingers is an uncommon condition caused by either congenital amniotic band syndrome or a variant of hypoplasia or aplasia. This 3-year-old child who has congenital amniotic band syndrome is an excellent candidate for reconstruction because, in patients with this syndrome, the structures that exist proximal to the level of deformity (eg, bone, nerves, muscles, tendons, and vessels) are unaffected. Therefore, toe-to-hand transfer would be most appropriate because it would provide the best sensorimotor function and aesthetic outcome. Toes can be transferred independently or as a group and positioned for either fine motor or grasp functions. Complications in the donor foot are typically minor. The growth of the transferred toe has been estimated as 90% of a normal toe; there is a 10% risk for premature physeal closure.

Occupational therapy would yield only limited functional improvement in a patient who has no functional fingers. Digital prostheses would provide aesthetic but not functional improvement. Metacarpal lengthening is performed to provide a post for the thumb to work against; reconstruction with a radial forearm flap could also create a thumb post. Both techniques are inferior to an appropriately placed, rehabilitated toe transfer.

References
1. Boyer MI, Mih AD. Microvascular surgery in the reconstruction of congenital hand anomalies. Hand Clin. 1998;14:135-142.
2. Kay SP, Wiberg M. Toe to hand transfer in children, part 1: technical aspects. J Hand Surg. 1996;21B:723-734.
3. Kay SP, Wiberg M, Bellew M, et al. Toe to hand transfer in children, part 2: functional and psychological aspects. J Hand Surg. 1996;21B:735-745.

A 1-year-old infant has the deformity shown in the photographs above. These findings are most consistent with which of the following?

(A) Arthrogryposis
(B) Complete thumb-index syndactyly
(C) Madelung's deformity
(D) Poland's syndrome
(E) Radial club hand

The correct response is Option E.

This infant has a radial club hand or radially deficient hand, involving partial or total absence of the radial or preaxial border of the upper extremity. Although radial club hand deformities can range from thumb hypoplasia to varying degrees of absence of the radius, resulting in radial deviation of the hand, most patients have total absence of the radius with absence of the radial carpal bones and thumb. It occurs in one in every 55,000 to 100,000 neonates and can be unilateral or bilateral. Abnormalities associated with radial dysplasia include cardiac septal defects (Holt-Oram syndrome), hematopoietic disorders (Fanconi anemia and TAR (thrombocytopenia-absent radius) syndrome), and gastrointestinal disorders (imperforate anus). Radial dysplasia may also occur as part of VATER syndrome (involving vertebral, anal, tracheoesophageal, and renal defects).

Fanconi aplastic anemia is the most serious condition associated with radial club hand. Affected patients also have pancytopenia, a progressive condition that may not be detected initially. Mitomycin testing should be performed in neonates with radial club hand to detect Fanconi anemia and prevent the development of life-threatening complications.

Arthrogryposis is a congenital disorder characterized by nonprogressive joint contractures present at birth. It is thought to occur secondary to neurogenic or myopathic weakness in utero. Multiple joints are typically affected; the extremities are atrophic and have limited active and passive motion. The wrist has a clublike appearance but is usually flexed and deviated ulnarly. Neurogenic and myopathic disorders are often associated with arthrogryposis.

Although this infant's deformity may appear similar to thumb-index syndactyly, this is a rare finding and would not be characterized by radial deviation of the carpus and hypoplasia of the thenar eminence, which are seen in this patient.
Madelung's deformity is a congenital disorder of the wrist that first becomes apparent in late childhood or adolescence. Affected patients have shortening of the radius, apparent palmar subluxation of the carpus, and prominence of the ulnar head. Finger abnormalities are not associated.

Patients with Poland's syndrome have unilateral findings including absence of the pectoralis major and minor muscles, hypoplasia of the breast, and preaxial deformities.

References
1. Ezaki M, Kay SP, Light TR, et al. Congenital hand deformities. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:519.
2. McCarroll HR. Congenital anomalies: radial dysplasia. In: Peimer CA, ed. Surgery of the Hand and Upper Extremity. New York, NY: McGraw-Hill, Inc; 1996;2:2075.

A 5-year-old child has an angular deformity of the ring finger; a photograph and radiograph are shown above. This finding is most consistent with which of the following?

(A) Complex incomplete syndactyly
(B) Fracture malunion
(C) Longitudinally bracketed epiphysis
(D) Madelung's deformity
(E) Osteoma of the proximal phalanx
The correct response is Option C.

These findings are most consistent with a longitudinally bracketed epiphysis. In this child's ring finger, there is a bracketed longitudinal growth plate with a reverse C-shaped configuration, rather than a normal transverse growth plate configuration. Longitudinal growth on the radial aspect of the phalanx is arrested but proceeds more normally on the ulnar aspect of the proximal phalanx, where the epiphysis is not bracketed. This finger deformity is most frequently associated with a delta phalanx, which is indeed present in this patient. However, a delta phalanx is more commonly evident in triphalangeal thumbs.

This child underwent release of simple, incomplete syndactyly of the third postaxial web space at age 8 months but subsequently developed a progressive angular deformity of the ring finger and severe scissoring beneath the long finger, as shown in the photograph. Angulation of greater than 5 degrees in any of the digits should be corrected surgically. Closing wedge osteotomy and epiphyseolysis with fat interposition were performed in this patient.

Complex incomplete syndactyly is characterized by webbing of the bone and soft tissues between adjacent digits that does not extend the length of the digits. Fracture malunion can be easily recognized on radiographs but is not seen in this patient. Patients with Madelung's deformity have arrested growth of the ulnar aspect of the distal radius resulting in a patterned wrist deformity. Osteoma of the proximal phalanx appears as a smooth, oval radiolucency of bone on radiographs.

References
1. Ezaki M, Kay SP, Light TR, et al. Congenital hand deformities. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:519.
2. Light TR, Ogden JA. The longitudinal epiphyseal bracket: implications for surgical correction. J Pediatr Orthop. 1981;1:299-305.

A 1-year-old infant has the malformation shown in the photograph above. Which of the following is most likely in this infant?

(A) Apert's syndrome
(B) Carpenter's syndrome
(C) Pfeiffer's syndrome
(D) Poland's syndrome
(E) No other associated syndromes

The correct response is Option E.

This infant with syndactyly will most likely have no other associated syndromes. Syndactyly occurs in one of every 2000 neonates and is typically an isolated deformity, although other malformations have been associated. Syndactyly can be complete or incomplete, reflecting the level of webbing distally to proximally, and complex or simple, reflecting the presence or absence of bony union. Complicated syndactyly implies involvement of other congenital abnormalities such as polydactyly.

Male infants are more commonly affected than female infants. Inheritance is more often sporadic than familial. Approximately 50% of affected patients have bilateral syndactyly. The third web space is affected most frequently.

Patients with Apert's syndrome have bilateral, symmetric, complex syndactyly with shortened fingers. Craniofacial deformities are characteristic. Carpenter's syndrome is characterized by simple syndactyly, shortened fingers, preaxial polysyndactyly, broad thumbs, and craniosynostosis. In Pfeiffer's syndrome, there is mild partial syndactyly, as well as broadened, deviated thumbs and severe midface hypoplasia. Poland's syndrome is associated with unilateral findings, including absence of the sternocostal portion of the pectoralis major muscle, hypoplasia of the upper extremity, simple syndactyly, and shortened fingers.

References
1. Fink SC, Hardesty RA. Craniofacial syndromes. In: Bentz ML, ed. Pediatric Plastic Surgery. Stamford, Conn: Appleton & Lange; 1998;1:1-43.
2. Upton J. Congenital anomalies of the hand and forearm. In: McCarthy JG, ed. Plastic Surgery. Philadelphia, Pa: WB Saunders Co; 1990;8:5213-5398.

Which of the following hand deformities is commonly associated with a delta phalanx?

(A) Brachydactyly
(B) Camptodactyly
(C) Clinodactyly
(D) Macrodactyly
(E) Symbrachydactyly

The correct response is Option C.

Clinodactyly, or "bent finger," is most commonly caused by the presence of a delta phalanx. Clinodactyly and triphalangeal thumb are most often associated with the presence of a delta phalanx, which has an angulated, short, tubular base, trapezoidal or triangular in shape. The growth plate is longitudinal, often a reverse C-shape or bracket, rather than transverse. The longitudinally bracketed epiphysis can interfere with normal longitudinal growth. Clinodactyly manifests as a radially or ulnarly curved digit. It is typically bilateral and is often transmitted as an autosomal dominant trait with variable expression. Although any digit can be involved, radial deviation of the small finger in the area of the distal interphalangeal joint is most common. In patients with delta phalanges, appropriate management includes bracket resection, fat grafting, and osteotomies, which can be either closing, opening, or reverse, as indicated by the findings in the affected patient.

The other hand deformities listed above can be associated with abnormally shaped phalanges but not with a delta phalanx.

Brachydactyly is a congenital deformity, typically autosomal dominant, that is characterized by abnormal shortening of the digits.

Patients with camptodactyly have a flexion deformity of the proximal interphalangeal joint, most frequently involving the small finger. Possible causes of camptodactyly include skin deficiencies, shortening of the volar plate, abnormalities of the palmar fascia and Landsmeer's ligament, deficiencies of the central slip, and shortening of the superficialis tendon. Static and dynamic splinting can be helpful; surgical correction is often incomplete.

Macrodactyly describes enlargement of all of the structures of a digit. Staged bony and soft-tissue reduction procedures can be performed to allow for some control. Attempting to halt digital growth with ligation of digital arteries or elastic compression is typically ineffective. Amputation is indicated for any large, unsightly digit that significantly impairs total hand function.

Symbrachydactyly is a congenital hand deformity characterized by shortened digits with syndactyly. Poland's syndrome is frequently associated. The digits are foreshortened but not angulated.

References
1. Ezaki MB, Kay SP, Light TR, et al. Congenital hand deformities. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:325-551.
2. Light TR. Congenital anomalies: syndactyly, polydactyly and cleft hand. In: Peimer CA, ed. Surgery of the Hand and Upper Extremity. New York, NY: McGraw-Hill; 1996;2:2111-2144.
3. Lister G, ed. The Hand: Diagnosis and Indications. 3rd ed. Edinburgh, Scotland: Churchill Livingstone, Inc; 1993:459-512.