Percutaneous Distal Soft Tissue Release–Akin Procedure, Clinical and Podobarometric Assessment With the BioFoot In-Shoe System

Abstract

Hallux valgus (HV) is a common, complex, and progressive deformity of the first ray, leading to biomechanical changes. The purpose of this study is to describe the midterm outcomes of the percutaneous distal soft tissue release-Akin procedure for mild hallux valgus on plantar pressures distribution, clinical outcome, and radiographic parameters. Twenty-six patients (30 feet) who had undergone this procedure were evaluated prospectively. The BioFoot in-shoe system was used for an objective functional evaluation of dynamic plantar pressures in the heel, midfoot, first through fifth metatarsal heads, hallux, and lesser toes. The clinical outcome measurements included preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) score. The radiological parameters measured were hallux abductus angle (HAA) and first intermetatarsal angle in weight-bearing radiographs. The average follow-up was 12.1 months. There were improvements in the AOFAS rating scale score from 68.7 to 88.1, in HAA from 25.4 degrees to 11.4 degrees, and in the first intermetatarsal angle from 12.0 degrees to 9.2 degrees. The pedobarographic analysis showed a statistically significant decrease (P < .001) in the maximum peak pressure (from 1037 to 498 kPa) and mean pressure (from 487 to 159 kPa) under the hallux. The percutaneous distal soft tissue release-Akin procedure improved the patients' clinical status and reduced the plantar pressures beneath the hallux. This improvement could be attributable to the removal of the medial eminence, which avoids pain around the first metatarsophalangeal joint, and to the Akin procedure, which provides a more physiological postoperative position of the hallux.