[Effectiveness of triple osteotomy in correcting severe hallux valgus with the first metatarsal pronation deformity]

To explore the effectiveness of triple osteotomy in correcting severe hallux valgus with the first metatarsal pronation deformity.

A retrospective analysis was conducted on the clinical data of 29 patients (40 feet) with severe hallux valgus accompanied by the first metatarsal pronation deformity, who were admitted between January 2022 and December 2023 and met the selection criteria. There were 8 males (10 feet) and 21 females (30 feet), with an average age of 50.0 years (range, 44-62 years). The disease duration ranged from 5 to 9 years (mean, 6.5 years). All patients underwent triple osteotomy to correct the deformity. The American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS) score were used to evaluate joint function and pain before and after operation. Based on pre- and post-operative X-ray films, hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA) were measured to evaluate the correction of hallux valgus; the shape classification of the lateral edge of the first metatarsal and the pronation of first metatarsal angle (PFMA) were observed to assess the correction of the first metatarsal pronation deformity.

A superficial infection occurred in 1 foot and the incison healed after dressing change; the remaining incisions healed by first intention. All patients were followed up 12-18 months (mean, 12.6 months). Three cases (4 feet) experienced limited movement of the metatarsophalangeal joint after operation, and the joint function recovered after strengthening functional exercises. During follow-up, no recurrence of deformity or secondary metatarsal pain occurred. Compared with preoperative scores, the AOFAS score increased and the VAS score decreased at last follow-up, and the differences were significant ( P<0.05). Radiographic examination showed that the osteotomy achieved bony healing, with the healing time of 2.5-6.2 months (mean, 4.1 months). The hallux valgus deformity was corrected, and the IMA, HVA, and DMAA were significantly smaller at last follow-up when compared with those before operation ( P<0.05). The first metatarsal pronation deformity was also corrected; there was no R-type (R-type for pronation deformity) on the lateral edge of the first metatarsal at last follow-up, and the PFMA decreased compared with preoperative levels ( P<0.05) and was corrected to the normal range.

Triple osteotomy can achieve good effectiveness for correcting severe hallux valgus with the first metatarsal pronation deformity. The functional training of the first metatarsophalangeal joint needs to be strengthened.