Arthrodesis of Ring and Small Carpometacarpal Joints

72 Arthrodesis of Ring and Small Carpometacarpal Joints

Indications

Painful arthritis of the ring and small carpometacarpal (CMC) joints recalcitrant to nonoperative management, or chronic ring and small CMC joint dislocation

Technique

Begin with 2.5 cm transverse incision ring and small carpometacarpal (CMC) joints. Bluntly dissect through subcutaneous incision. Protect branches of ulnar sensory nerve. Identify extensor digitorum communis (EDC), extensor digiti quinti (EDQ), and extensor carpi ulnaris (ECU) tendons (Fig. 72-1).
Retract EDC and EDQ in a radial direction and ECU in an ulnar direction. Identify ring and small CMC joints. Use fluoroscopy if anatomy is distorted by injury.
Remove osteophytes and excessive bone formation around CMC joints. Excavate any remaining cartilage from the base of the metacarpals and corresponding hamate (H) joints (Fig. 72-2A,B).
Reduce any CMC joint malalignment or subluxation. Reduction verified using fluoroscopy.
Percutaneous fixation with oblique 0.45 in. (1.1 mm) trocar-tipped wires drilled across ring and small CMC joints. Adjust pin position and length using fluoroscopy (Fig. 72-3).
Bone graft any defects within CMC joint fusion mass. Bone graft is harvested from the distal radius. Iliac crest bone graft is alternative option.
The wires are either retained in a percutaneous position or preferably cut beneath the skin.