Case-control study on Scarf and double metatarsal osteotomy of the first metatarsal for the treatment of hallux valgus deformity

Abstract

To compare clinical efficacy of scarf osteotomy and double metatarsal osteotomy(DMO) in treating moderate to severe hallux valgus. Fifty patients (81 feet) with moderate to severe hallux valgus deformity were treated from January 2017 to December 2019, and were divided into Scarf osteotomy (SO) group or DMO group according to different osteotomy methods. There were 26 patients (44 feet) in SO group, including 1 male and 25 females, aged from 48 to 65 years old with an average of (55.5±4.67) years old;18 patients (30 feet) with moderate and 8 patients (14 feet) with severe. There were 24 patients(37 feet) in DMO group, including 1 male and 23 females, aged from 45 to 62 years old with an average of (52.1±6.8) years old;there were 14 patients (24 feet) with moderate and 10 patients (13 feet) with severe. Hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA) and relative length of the first metatarsal(RLFM) on weight-bearing anteroposterior radiographs before and after operation were compared. American Orthopaedic Foot and Ankle Society (AOFAS) hallux, metatarsal, and interphalangeal joint scores was used for evaluate clinical effects. Weight bearing time and complications were observed. Fivty patients were followed up. The follow-up time in SO group ranged from 12 to 36 months with an average of(20.50±6.22) months and from 16 to 28 months with an avaerge of(19.80±2.44) months in DMO group while there was no significant difference between two groups(P>0.05). All incision healed at stage I, and osteotomy healed at (20.31±3.17) months after operation. One patient occurred hallux adduction deformity, without transferred metatarsalgia;2 patients occurred metastatic metatarsalgia in DMO group. There were no significant difference in HVA, IMA, DMAA, and AOFAS scores between two groups(P>0.05) before and after operation. There was no significant difference in RLFM between two groups(P>0.05), while had significant difference in RLFM between two groups at final follow-up (P<0.05). Partial weight-bearing time and full weight-bearing time in SO group were significantly earlier than those in DMO group (P<0.05). Both of Scarf osteotomy and the first metatarsal biplane osteotomy could effectively treat moderate to severe hallux valgus deformity, with similar imaging and clinical evaluation. However, the relative length of the first metatarsal bone in SO group was longer than that in DMO group after operation, and the time of weight bearing in Scarf osteotomy is earlier than that of double metatarsal osteotomy of the first metatarsal.