The Mitchell and Scarf osteotomies for hallux valgus correction: a retrospective, comparative analysis using plantar pressures.

A retrospective analysis was performed to describe the effects of Mitchell and Scarf osteotomies on plantar pressure distribution and their relevance to the clinical outcome. This study evaluated 28 patients who underwent operations for moderate to severe hallux valgus deformities over a period of 3 years at 2 different centers. Twenty-two Mitchell and 22 Scarf osteotomies were performed on 28 patients with a mean follow-up of 23 months (13-62 months). The average postoperative American Orthopaedic Foot and Ankle Society scores after Mitchell and Scarf osteotomies were 74 and 84, respectively. A control group of 15 individuals with 20 healthy feet were included for comparison. The plantar pressures were documented with the Musgrave footplate. The pressure distributions under the first metatarsal head were within normal limits in both study groups compared with the control group (P = .77). After Mitchell osteotomies, deficient load bearing was noted under the hallux (P = .007), coupled with overloading of the second and third metatarsal heads (P = .01). But after the Scarf procedures, increased weight bearing was noted at the heel (P = .04) and midfoot (P = .09), with better load distribution under the hallux. However, it was not comparable with the control group. Correlation of American Orthopaedic Foot and Ankle Society scores and pressure variables demonstrated a significant positive correlation with hallux loading (P = .001). This study demonstrates that adequate hallux loading is imperative for a better outcome of the procedure. Mitchell and Scarf osteotomies do not restore the load-bearing function of the foot to normal, whereas hallux loading plays an important role for a better outcome of the procedure.