(A) Birth to 3 months
(B) 4 to 9 months
(C) 12 to 18 months
(D) 24 to 30 months
(E) After 36 months

The correct response is Option C.

Syndactyly is a common congenital hand anomaly, occurring in one of every 2500 neonates. Familial inheritance ranges from 10% to 40%, and boys are twice as likely as girls to be affected. Syndactyly can be simple or complex and complete or incomplete. Patients with simple syndactyly have fusion of the skin of adjacent digits. In complex syndactyly, the skin and bones are fused. Complete syndactyly encompasses the entire web space. In patients with incomplete syndactyly, only part of the web space is fused.

The infant shown in the photograph above has incomplete syndactyly because the entire web space is not involved. However, because there are no additional radiographs, a diagnosis of simple or complex syndactyly cannot be determined.

Most infants with syndactyly undergo release before 18 months of age. During this period, the digits have grown to an adequate size, anesthetic complications are decreased, and hand dominance has not yet developed. Some surgeons have performed surgery as early as 6 weeks of age. Infants who have syndactyly of the other web spaces, especially the first and fourth, should undergo surgery at an earlier age because of the greater risk for differential growth. It is no longer customary to wait until the child reaches school age or older because of functional and cosmetic factors.

References
1. Ezaki M, Kay SP, Light T, 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. Smith P, Laing H. Syndactyly. In: Gupta A, Kay SP, Scheker LR, eds. The Growing Hand. London, England: Mosby Ð Year Book, Inc; 2000:225-230.

PHOTO

A neonate has severe swelling and congestion of the right hand; photographs are shown above. The right leg was autoamputated below the knee at birth. Which of the following is the most appropriate management?

(A) Observation
(B) Elevation of the hand and gentle compression
(C) Fasciotomies of the hand and extrinsic musculature
(D) Excision of the constricting band with interdigitating Z-plasty flaps
(E) Amputation

PHOTO

The correct response is Option D.

This neonate has amniotic constriction band syndrome that has resulted in severe edema of the hand, and urgent intervention is required because of the risk for vascular congestion and necrosis. Amniotic constriction bands are an embryologic anomaly with no genetic predisposition. The bands can be released partially or completely; partial release is advocated if additional vascular compromise is noted intraoperatively. In this patient, the constriction band has impinged all tissues to the skeletal structures, but complete excision is possible. Z-plasty is recommended for repair because of the severe circumferential size difference between the proximal and distal parts of the arm. This technique provides a greater surface area to allow establishment of lymphatic and venous drainage channels. In patients with less severe constriction banding, observation or delayed release is most appropriate.

The photograph above shows the results seven days after excision of the constricting band and multiple Z-plasties.
Observation without intervention is most likely to result in eventual autoamputation of the hand. Elevation of the hand will not relieve the severe congestion associated with this constriction band, and compression would further worsen the compromised vascular supply. Fasciotomies are contraindicated because this patient does not have signs consistent with compartment syndrome. Amputation is reserved for patients who have severe necrosis following failed attempts at hand salvage.

References
1. Doyle JR. Constriction ring reconstruction. In: Blair WF, ed. Techniques in Hand Surgery. Baltimore, Md: Williams & Wilkins; 1996:1106-1110.
2. Ezaki MB. Amnion disruption sequence. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:429-431.
3. Wiedrich TA. Congenital constriction band syndrome. Hand Clin. 1998;14:29-37.

A neonate has thumb hypoplasia and a shortened forearm with radial curvature. The child's mother has a similar deformity. Which of the following is the most closely associated condition?

(A) Fanconi anemia
(B) Klippel-TrŽnaunay syndrome
(C) Maffucci syndrome
(D) Poland syndrome
(E) Sturge-Weber syndrome

The correct response is Option A.

This neonate has a radial club hand, an anomaly of unknown cause that may possibly be associated with autosomal dominant inheritance. Radial club hand deformities can range from partial underdevelopment to total absence of the radial elements of the upper extremity. Conditions associated with radial dysplasia include VATER syndrome (involving vertebral, anal, tracheoesophageal, and renal defects), Holt-Oram syndrome (involving cardiac septal defects), gastrointestinal disorders, and hematologic abnormalities including Fanconi anemia and thrombocytopenia-absent radius (TAR) syndrome.

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.

Klippel-TrŽnaunay syndrome is characterized by musculoskeletal limb-length discrepancies involving one extremity, typically the leg, with associated venous and lymphatic malformations. Club hand is not seen.

Maffucci syndrome involves multiple enchondromas and venous and lymphatic anomalies. The limbs are usually foreshortened. Exostoses may be noted on the fingers.

Poland syndrome typically involves preaxial hypoplasia of the chest wall and upper extremity unilaterally. Affected patients have absence of the pectoralis major and minor muscles and limb hypoplasia with syndactyly and brachydactyly.

Patients with Sturge-Weber syndrome have port-wine stains in the distribution of the first and second divisions of the trigeminal nerve (V1and V2) associated with seizures and ipsilateral leptomeningeal calcifications.

References
1. Alter BP. Arm anomalies and bone marrow failure may go hand in hand. J Hand Surg. 1992;17A:566-571.
2. Kessler I. Centralization of the radial club hand by gradual distraction. J Hand Surg. 1989;14B:37-42.

Which of the following is NOT a cause of the thumb-in-palm deformity in patients with cerebral palsy?

(A) Flaccidity of the extensor and abductor tendons of the thumb
(B) Hypomobility of the metacarpophalangeal joint of the thumb
(C) Skin contracture of the first web space
(D) Spasticity of an adductor tendon of the thumb
(E) Spasticity of a flexor tendon of the thumb

The correct response is Option A.

In patients with cerebral palsy, the thumb-in-palm deformity significantly limits function of the hand. The House classification is used to stratify the thumb-in-palm deformity according to four types. Type I is a simple adduction contracture of the metacarpal that results from spasticity of the adductor and first dorsal interosseous tendons. The type II deformity is similar to type I but also includes a flexion deformity of the metacarpophalangeal (MP) joint that is caused by spasticity of the flexor pollicis longus tendon. Patients with type III deformity have a simple adduction contracture of the metacarpal in conjunction with a hyperextension deformity and/or instability of the MP joint; this deformity results from spasticity of the adductor, first dorsal interosseous, and extensor pollicis brevis tendons and hyperextensibility of the MP joint. A type IV deformity is similar to type I deformity but also includes spasticity of the flexor pollicis longus tendon.

Treatment of the thumb-in-palm deformity involves release of the spastic muscles and stabilization of the joint.

Contracture of the first web space is also likely to exacerbate a thumb-in-palm deformity. Flaccidity of the extensor and abductor tendons of the thumb does not produce this deformity.

References
1. Gerwin M. Cerebral palsy. In: Green DP, Hotchkiss RN, Pederson WC, eds. Operative Hand Surgery. 4th ed. New York, NY: Churchill Livingstone, Inc; 1999;1:259.
2. House F. Disorders of the thumb in cerebral palsy, stroke, and tetraplegia. In: Strickland JW, ed. The Thumb. New York, NY: Churchill Livingstone, Inc; 1994.