Residual flexion deformity after scaphoid nonunion surgery: 7-year follow-up study

The clinical implication of a residual flexion deformity following surgery for scaphoid nonunion is unclear. Sixty-three patients who underwent scaphoid nonunion surgery were assessed after a mean of 7 years (range 5-10) to analyse the outcomes based on the presence of residual scaphoid deformity. Primary outcome was Disabilities of the Arm, Shoulder and Hand score. Secondary outcomes were Patient-Rated Wrist Evaluation score, wrist range of motion and strength. Patients were dichotomized to residual deformity or no deformity. Scaphoid deformity was calculated from CT scans based on the median difference between the height-length ratio of the operated versus the uninjured scaphoid. There were no differences between residual deformity (n = 33) and no deformity (n = 30) in any outcome variables, except for wrist extension which was slightly worse in the deformity group. The deformity group had a greater number of radiographic osteoarthritis, but all cases were mild, and osteoarthritis did not correlate to a worse outcome. We conclude that residual scaphoid deformity has no relevant negative impact on mid-term wrist function.Level of evidence: IV.