The Influence of the Length of the First Metatarsal on Transfer Metatarsalgia after Wu's Osteotomy

Abstract

Background The aim of this study was to evaluate how changes in the length of the first metatarsal, hallux valgus angle (HVA), intermetatarsal 1–2 angle (IMA), plantar angulation and sesamoid position influence the severity of the postoperative 2–5 metatarsalgia and to determine patient satisfaction with the cosmetic outcome after Wu's osteotomy. Materials and Methods A retrospective analysis of the clinical data and radiographs of 87 cases was performed at a mean followup time of 4.2 years after Wu's subcapital cross osteotomies. Results The mean HVA decreased from 42 to 13 degrees, the mean IMA 1–2 from 22 to 10 degrees. The mean first metatarsal lengthening was 0.3 mm. A negative correlation was found between lengthening of the first metatarsal and metatarsalgia at rays 2 and 3. No such pattern was found between the fourth and fifth metatarsal. No correlation was found between the 2–5 metatarsalgia and the decrease in either the HVA or the IMA 1–2. A positive correlation was detected between the HVA decrease and the patients’ satisfaction with their postoperative foot alignment; there was no correlation between the perceived postoperative foot alignment and either the first metatarsal lengthening or the IMA 1–2 decrease. Conclusion Preservation of the length of the first metatarsal during osteotomy seems to prevent the postoperative transfer metatarsalgia on the second and third rays; however, it has no major influence on the satisfaction of the patients with their foot alignment. A greater correction of the HVA angle resulted in a higher level of satisfaction with the foot cosmesis.