[Minimally invasive cotton osteotomy : Surgical technique and functional outcomes].

Abstract

Objective: The primary objective of the minimally invasive Cotton osteotomy is to correct sagittal malalignment of the medial column by targeted plantarflexion, thereby restoring alignment and contributing to the reconstruction of complex pes planovalgus deformities within a joint-preserving surgical approach.

Indications: The procedure is indicated in cases of flexible forefoot supination as part of a progressive collapsing foot deformity (PCFD), particularly when isolated hindfoot correction is insufficient to re-establish medial arch stability. Additional indications include tibialis posterior tendon insufficiency and overload syndromes of the medial column.

Contraindications: Contraindications include general surgical inoperability and acute infection at the operative site. Relative contraindications comprise advanced peripheral arterial disease, severe osteoporosis, neuropathic foot deformities with loss of protective sensation, and symptomatic arthritis of the medial column joints.

Surgical technique: The Cotton osteotomy is performed via a minimally invasive, closed-wedge technique through a small plantar-medial incision. A wedge-shaped bone fragment is resected from the medial cuneiform using a Shannon burr. The osteotomy gap is then closed by controlled compression to achieve plantarflexion of the medial ray. Fixation is accomplished with a percutaneously inserted, cannulated compression screw under fluoroscopic guidance.

Postoperative management: Postoperatively, patients are immobilized in a below-knee walker boot with touch-down weight-bearing for six weeks. After radiographic confirmation of consolidation, progressive loading is initiated with transition to full weight-bearing and regular footwear around week 12. Physical therapy supports restoration of mobility and strength throughout the recovery period.

Results: This retrospective study included 13 feet in 12 patients who underwent minimally invasive Cotton osteotomy as part of a combined hindfoot reconstruction. Significant functional improvement was observed, with the AOFAS score increasing from 71.5 ± 14.0 preoperatively to 91.0 ± 5.6 postoperatively (p < 0.05), corresponding to a very large effect size (Cohen's d = 2.20). One case of prolonged wound secretion occurred at the calcaneal osteotomy site and was managed conservatively without revision surgery.