Free-vascularized medial femoral condyle bone transfer in the treatment of scaphoid nonunions.

Abstract

Scaphoid nonunions with associated avascular necrosis and carpal collapse have proven difficult to treat reliably. This study outlines the rationale and approach to the use of a free-vascularized medial femoral condyle bone graft and the authors' experience with it in the treatment of scaphoid nonunions. A retrospective review was conducted to identify all patients with scaphoid nonunions with avascular necrosis and carpal collapse treated with a medial femoral condyle bone graft. Between July of 2004 and August of 2007, 12 such patients (12 men and no women), with a mean age of 25.3 years (range, 18 to 40 years), were identified. Nine of the twelve had failed prior operative treatment. Mean duration of nonunion was 20 months (range, 4 to 36 months). Carpal indices, time to union, early functional outcomes, and complications were recorded. All 12 nonunions healed at a mean of 13 weeks (range, 6 to 26 weeks). Radiographic evaluation demonstrated significant improvement from preoperative to postoperative mean lateral intrascaphoid angle (66 and 28 degrees, respectively; p = 0.00005), scaphoid height-to-length ratio (0.78 and 0.65 respectively; p = 0.006), scapholunate angle (63 and 49 degrees, respectively; p = 0.001), and radiolunate angle (15 and 6 degrees, respectively; p = 0.0005). Five patients underwent subsequent procedures (one radial styloidectomy and four Kirschner wire removals, with one concurrent donor-site stitch abscess débridement). Free-vascularized medial femoral condyle grafts provide both blood supply and structural support to restore scaphoid vascularity and architecture, thereby promoting union. These results suggest that this graft is a promising alternative in the treatment of scaphoid nonunions associated with avascular necrosis and carpal collapse.