Aims: Passively correctible, adult-acquired flatfoot deformities (AAFD) are treated with joint-sparing procedures. Questions remain as to the efficacy of such procedures when clinical deformities are severe. In severe deformities, a primary fusion may lead to predictable outcomes, but risks nonunion. We evaluated pre- and postsurgical flexible AAFD patients undergoing joint-sparing or fusion procedures, comparing reoperation and complication rates.
Methods: We identified patients with flexible AAFD between January 1, 2001 and 2016. Exclusion criteria were incomplete medical record, rigid AAFD, and prior flatfoot surgery. Patient demographics, pre- and postsurgical radiographic measurements, surgery performed, and postoperative complications were evaluated by bivariate analysis, comparing joint-sparing versus fusion procedures.
Results: Of 239 patients (255 feet) (mean follow-up 62 ± 50 months), 209 (87%) underwent joint-sparing reconstructions, 30 (12.6%) underwent fusions. Fifty-four (24.1%) feet underwent joint-sparing reconstruction with reoperation versus 11 (35.5%) in fusion patients (P = .17). Radiographic improvement in talonavicular angle, talar first-metatarsal (anteroposterior view), and Meary's angle was higher in fusion patients (P < .001, P < .001, and P = .003, respectively).
Discussion: More nonunion reoperations among fusion patients were offset by reoperations in joint-sparing patients. Fusion uniquely corrected Meary's angle. Nonunion is of less concern for joint-sparing versus fusion for patients with severe flexible AAFD. Degree of deformity versus advantage of joint motion should improve decision making.
Levels of evidence: Level IV: Retrospective case series.
Keywords: adult-acquired flatfoot deformities (AAFD); flexible flatfoot; fusion; reconstruction.