Primary Treatment of Scaphoid Nonunions with Proximal Pole Avascular Necrosis with a Medial Femoral Condyle Free Vascularized Bone Graft
Kathleen Kollitz, MD; Nicholas Pulos, MD; Allen T. Bishop, MD; Alexander Y. Shin, MD
Mayo Clinic, Rochester, MN
Hypothesis: Several pedicled and free-vascularized bone grafts have been described for the treatment of scaphoid nonunions. The purpose of this study is to determine the outcome of free-vascularized medial femoral condyle bone grafts in the treatment of scaphoid nonunions with avascular necrosis. We hypothesize that this treatment restores scaphoid vascularity and architecture in patients who have documented avascular necrosis of the proximal pole resulting from scaphoid nonunion.
Methods: A retrospective review was conducted to identify all patients with scaphoid nonunions with avascular necrosis treated with a free-vascularized medial femoral condyle bone graft. Between June of 2006 and October of 2016, 37 patients were identified. Mean time from injury to surgery was 20.8 months. All patients had documented avascular necrosis of the proximal pole at the time of surgery evaluated by deflation of the tourniquet and lack of bleeding of the proximal pole. Union was defined as bridging trabeculae on plain radiographs and computed tomographic (CT) scan. Carpal indices, time to union, early functional outcomes and complications were recorded.
Results: Thirty five of 37 (94.6%) patients treated with free-vascularized medial femoral condyle bone grafting healed at a mean of 15.4 weeks (range, 5 to 50 weeks). Radiographic evaluation demonstrated significant improvement from preoperative to postoperative scaphoid height to length ratio (0.76 and 0.63, respectively, p < 0.0001 ), lateral scaphoid angle (32.90 and 16.42 degrees, respectively, p < 0.0001), scapholunate angle (70.34 and 54.93 degrees, respectively, p < 0.0001), and radiolunate angle (19.35 and 4.25 degrees, respectively, p < 0.0001). Ten patients underwent subsequent procedures of which eight were hardware removals (3 planned Kirschner wire removals, 5 screw removals with or without bone grafting). One patient underwent scaphoidectomy and 4-corner fusion 15 months post-operatively after suffering a subsequent injury. Another patient underwent 1,2-intercompartmental supraretinacular artery-based vascularized bone grafting four months after the procedure and the scaphoid excision with four corner fusion four years later. There were no donor-site complications related to the vascularized bone graft harvest.
Summary We present the largest series to date of patients treated with free-vascularized medial femoral condyle grafts for scaphoid nonunions with documented avascular necrosis of the proximal pole.
Level of Evidence IV
Back to 2018 ePosters