Both-bone forearm osteotomy for supination contracture: a cadaver model.

PURPOSE: To quantify the magnitude of rotational correction possible when comparing a single forearm bone osteotomy and fixation with stepwise osteotomy and fixation of both bones in a cadaver model and to determine if the order in which the stepwise osteotomies are performed influences the amount of correction.

METHODS: Ten fresh-frozen cadaveric forearms were fixed to a frame positioned in the field of view of a motion-capture system. An experimental supination contracture was induced in full supination. Cadaver forearms were assigned randomly to group I (ulna osteotomy, rotation, plating) or group II (radius osteotomy, rotation, plating). Cadavers in group I were used later in group III (ulna + radius) by completing a radial osteotomy, rotation, and fixation in the forearms with the plated ulna. Similarly the specimens assigned to group II were used later in group IV (radius + ulna) by completing an ulna osteotomy, rotation, and fixation in the forearms with the plated radiuses. Measurements of forearm pronation were made after single-bone (groups I, II) and stepwise both-bone (groups III, IV) rotational osteotomies.

RESULTS: Stepwise rotational osteotomy and fixation of the ulna followed by the radius produced significantly more corrective pronation (101 degrees) than rotating the radius followed by the ulna (65 degrees). Rotating the radius gave only moderate correction (58 degrees) and minimal correction was produced by ulna osteotomy alone (15 degrees).

CONCLUSIONS: Rotational osteotomy of both forearm bones can create approximately 100 degrees of correction when performed at the proximal ulna followed by the distal radius. If less rotation is needed then the distal radius osteotomy alone can provide approximately 60 degrees of correction.