Closing Wedge Osteotomy of Carpus

60 Closing Wedge Osteotomy of Carpus

Indications

Arthrogryposis with a fixed flexion and ulnar deviation deformity of the wrist

Technique

Dorsal transverse or semicircular incision across the midcarpal joint (Fig. 60-1)
Protect the cutaneous branches using loupe magnification. Elevate flaps at the level of the extensor retinaculum.
Isolate the wrist and finger extensor tendons. Identify the extensor pollicis longus (EPL) tendon and open the third compartment. Mobilize the EPL in a radial direction. The radial wrist extensors are usually hypoplastic and adherent to the dorsal capsule. Attempt to mobilize these tendons in a radial direction.
Isolate extensor carpi ulnaris (ECU) tendon. Palpate muscle-tendon junction ~6 to 8 cm above wrist. Make transverse incision at this level and identify proximal tendon. Incise distal aspect of tendon. Pull cut end of tendon into proximal incision (Fig. 60-2. S, scaphoid; H, hamate; Tg, triquetum).
Retract the extensor digitorum communis tendons in an ulnar direction. Identify the extensor carpi ulnaris tendon and divide at its insertion into the fifth metacarpal.
Make a transverse arthrotomy at the midcarpal joint. Elevate the capsule in a proximal and distal direction to expose the radiocarpal and midcarpal joint.
Place a 0.045–in. wire into the lunate (L) perpendicular to the long axis of the forearm. Place a second 0.045–in. wire into the capitate (C) perpendicular to the long metacarpal. The wires should converge at the base of the midcarpal joint. Verify wire position by fluoroscopy. The angle created by these wires outlines the wedge resection.
Cut the proximal carpal row parallel to the first wire and the distal carpal row parallel to the second wire. A scalpel is used in the young child and an osteotome or saw is used in older patient. The wedge can be slightly greater at the radial carpus to correct any ulnar deviation deformity (i.e., biplanar correction) (Fig. 60-3A–D).
Remove the intervening bone and close the osteotomy site by placing the wrist into extension. Place nonabsorbable sutures across the osteotomy site. Supplemental wire fixation can be added (Fig. 60-4).
Close the dorsal capsule. Transfer the extensor carpi ulnaris to the radial wrist extensors (Fig. 60-5). Close subcutaneous tissue and skin. Redundant skin can be excised through the ECRB.