Functional, Radiological, and Biomechanical Outcomes Following Deformity-Driven Multilevel Surgical Correction for Fixed Cavovarus Foot Deformity.

Abstract

Fixed cavovarus foot deformity is characterised by a plantar-flexed first ray, hindfoot varus, and abnormal plantar loading, often resulting in pain, instability, and gait dysfunction. The surgical correction we performed involved a deformity-driven approach to address the structural apex and associated components. Evidence linking this multilevel correction strategy to objective biomechanical improvement remains limited. This prospective case series evaluated outcomes following a uniform deformity-driven multilevel surgical correction protocol for fixed cavovarus deformity consisting of combined Cole midfoot osteotomy, Dwyer calcaneal osteotomy, and open Achilles tendon lengthening performed in all cases. Thirty-two relatively young skeletally mature patients (37 feet), predominantly with neuromuscular etiology, were included and followed for a minimum of 18 months. Primary outcome measures were patient-reported functional outcomes assessed using the Foot and Ankle Ability Measure Activities of Daily Living subscale (FAAM-ADL), radiologic alignment parameters on standardised weight-bearing radiographs, and objective gait and plantar pressure metrics. Secondary outcomes included postoperative complications. The Foot and Ankle Disability Index (FADI) was analysed as a secondary patient-reported outcome. FAAM-ADL scores improved significantly from a preoperative mean of 45.2 to 77.2 at 18 months (<i>P</i> < .001). All radiologic parameters demonstrated significant correction, including Meary angle, calcaneal pitch angle, lateral talocalcaneal angle, anteroposterior talometatarsal angle, and talonavicular coverage angle (all <i>P</i> < .001). Gait analysis demonstrated a significant increase in comfortable walking speed (1.0 to 1.4 m/s, <i>P</i> < .001) and redistribution of plantar loading, with reduced lateral column pressures and increased midfoot contact area (all <i>P</i> < .001). The secondary FADI score also improved significantly over time (<i>P</i> < .001). Complications included transient postoperative pain during the first 12 months, 1 superficial wound infection, and 1 case of deformity recurrence. In this prospective case series, deformity-driven multilevel surgical correction for fixed cavovarus deformity with a midfoot apex was associated with significant improvements in patient-reported function, radiologic alignment, and objective biomechanical parameters. These findings support the role of apex-targeted multilevel correction in appropriately selected patients with rigid midfoot-driven cavovarus deformity.