[Clinical effect of metatarsal diaphysis Z-shaped rotating osteotomy in moderate and severe hallux valgus with metatarsophalangeal joint incongruency].

Objective: To evaluate the clinical effect of Z-shaped rotating osteotomy of metatarsal diaphysis in patients with moderate and severe hallux valgus with metatarsophalangeal joint incongruency. Methods: We selected 36 patients (38 feet) with moderate and severe hallux valgus with metatarsophalangeal joint incongruency who underwent Z-shaped rotating osteotomy of metatarsal diaphysis in the First Affiliated Hospital of Army Medical University of Chinese PLA from September 2010 to January 2019. There were 2 males and 34 females with an average age of (49±18) years (18-77 years). Hallux valgus angle (HVA), first-second intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), congruency index, length of first metatarsal, and functional scores were evaluated before and 6 weeks after surgery and at the last follow-up. The data were compared by one-way ANONA or t test. Results: The congruency index was significantly improved from 0.75±0.11 before surgery to 0.95±0.07 at the last follow-up ( t= 11.728, P< 0.01). HVA and IMA improved significantly at 6 weeks after surgery, however, HVA at the last follow-up showed an increased trend compared with that at 6 weeks after the operation, while no significant improvement in IMA. Although DMAA increased slightly 6 weeks after surgery when compared with that before surgery, there was no significant difference in it between the last follow-up and the 6 weeks after surgery, and no significant difference in the length of the first metatarsal at different time points ( F= 0.991, P> 0.05). In terms of functional scores, American Orthopaedic Foot & Ankle Society (AOFAS) score increased from 50±9 before surgery to 80±17 at the last follow-up, while visual analogue scale (VAS) decreased from 5.8±1.1 to 2.7±1.5, Manchester-Oxford Foot Questionnaire (MOXFQ) score decreased from 70±13 to 25±19 ( t= 12.024, 13.439, 16.880, all P< 0.05). Conclusions: The treatment of moderate and severe hallux valgus with metatarsophalangeal joint incongruency by Z-shaped rotating osteotomy of metatarsal diaphysis can significantly increase the congruency index of metatarsophalangeal joint and improve the metatarsophalangeal joint matching relations. It will not significantly increase the DMAA. A certain degree of radiographic recurrence occurs during a longtime follow-up, but it doesn't influence the symptoms and function.