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Introduction: Scaphoid waist and proximal pole fractures that fail to unite are prone to developing avascular necrosis (AVN) of the proximal pole and a flexion or “humpback” deformity with dorsal intercalated instability (DISI) as the proximal pole extends with the lunate and the distal pole flexes. Treatment of these difficult nonunions must restore blood supply and correct carpal alignment to optimize results. The purpose of this study is to update the union rates of scaphoid nonunions with avascular necrosis and collapse treated with medial femoral condyle vascularized bone grafts and review the radiographic and clinical outcomes of the procedure.

Materials & Methods: A retrospective chart review for all patients (n = 49 patients) treated with a vascularized bone graft from the medial femoral condyle for scaphoid nonunion was performed. Pre-operative and post-operative radiographic studies were reviewed and carpal alignment (scaphoid height:length ratio, triangulation intercarpal ratio, revised carpal height, scapholunate and radiolunate angles) measured and time to bony union determined. Pre-operative and post-operative clinical notes were reviewed and range of motion and grip strength compared.

Results: Forty six (94%) of the 49 patients with nonunion went on to unite at an average of 15 weeks (range 6-56 weeks) post-operatively. Eleven patients required subsequent procedures (2 scaphoidectomy and four-corner fusion for persistent nonunion and fragmentation, 2 subsequent bone grafting procedures to achieve union, 4 screw removal or exchange, 1 wrist arthroscopy, 1 radial styloidectomy, 1 posterior interosseous neurectomy, 5 K-wire removal,). Scaphoid geometry and carpal alignment improved significantly (p<0.05) post-operatively. Range of motion was not significantly changed post-operatively. Grip strength improved from 64% to 86% of the contralateral side post-operatively (p<0.001).

Conclusions: Vascularized bone grafts from the medial femoral condyle are useful in restoring scaphoid geometry and achieving a high rate of union in the challenging subset scaphoid nonunions complicated by AVN and humpback deformity.