Minimally Invasive Procedure for Correcting Extra-Articular Malunions of Metacarpals and Phalanges.

PURPOSE: Extra-articular malunions of metacarpals and phalanges may cause palmar pain, finger scissoring, and splaying, and interfere with function. Current treatment involves open osteotomy and fixation with plates and screws. We present a minimally invasive method using cannulated headless screws for correction of malunions and examine the outcomes in a series of patients.

METHODS

Twenty malunions were operated on in 17 patients. In 16 cases, the malunion involved the metacarpal and in 4 it involved the proximal phalanx. All proximal phalanx and 3 metacarpal malunions were malrotation types, while the rest of the metacarpal malunions were dorsal angulations. The operation consisted of an opening wedge osteotomy in 8 patients; closing wedge osteotomy in 5; and a transverse osteotomy and derotation in the rest. Concomitant surgery to release tendon adhesions or contracted joints or to perform adipofascial flaps was performed in 8 cases. Fixation was achieved by means of a cannulated headless screw. Immediate range of motion was permitted in all cases.

RESULTS

Correction of the malunion and osteotomy union was achieved in all cases. One patient required manipulation of a digit that was found rotated at the first follow-up visit. Eleven fingers achieved more than 280° of total active motion. In 9 digits, the total active motion was less than 280° after the operation, yet improved 76° (range, 140°-30°) from their preoperative total active motion. The mean single-assessment numeric evaluation score for the whole group was 9.1.

CONCLUSIONS

The fixation provided by the cannulated headless screw is sufficient to permit immediate range of motion. Due to the minimal tissue disruption, this approach may be a reasonable alternative to the standard approach.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.