Effects of tibial sesamoid position on the functional recovery after the hallux valgus surgery

BAI Dong-yu; XUE Liang

doi:10.3969/j.issn.2095-252X.2018.04.014

Abstract：Objective Hallux valgus surgery can change the tibial sesamoid position (TSP) and the first metatarsal bone, so this study aims to investigate effects of TSP on the functional recovery after the hallux valgus surgery. Methods This study enrolled 300 patients who underwent hallux valgus surgery in our department from January 2008 to June 2015. All of them were followed up for 2 years. The TSP, hallux valgus angle (HVA) and intermetatarsal angle (IMA) were assessed by weight-bearing anteroposterior X-ray examination pre- and postoperation. All patients were divided into the normal sesamoid group (I - IV) and outlier sesamoid group (V - VⅡ) according to the postoperative TSP grade. Visual Analog Scale (VAS) and AOFAS Hallux Metatarsophalangeal-Interphalangeal Scale (AOFAS) in 2 groups were compared respectively. Multivariate Logistics regression analysis was used to determine the independent risk factors of functional outcomes after hallux valgus surgery. Results The TSP ratio of the tibial sesamoid bone was 85.0％ preoperatively and 24.3％ postoperatively (P ＜ 0.001). The HVA angle of the valgus angle was (30.8 ± 10.8) ° preoperatively and (13.6 ± 7.4) ° postoperatively (P ＜ 0.001); IMA was (14.3 ±4.0) ° preoperatively and (7.9 ± 3.5) ° postoperatively (P ＜ 0.001); VAS score was (5.5 ± 2.0) preoperatively, (0.8 ±0.5) 6 months postoperatively and (0.5 ± 0.5) 2 years postoperatively in the normal TSP group, and (5.8 ± 2.5) preoperatively, (2.0 ± 1.3) 6 months postoperatively and (2.0 ± 0.8) 2 years postoperatively in the outlier TSP group. The VAS scores of the normal TSP group were significantly lower than those of the outlier TSP group 6 months and2 years after the operation respectively (P ＜ 0.001, P ＜ 0.001). AOFAS score was (56 ± 5) preoperatively, (80 ± 4) 6 months postoperatively and (87 ± 2) 2 years postoperatively in the normal TSP group, while (55 ± 7) preoperatively, (72 ± 5) 6 months postoperatively and (76 ± 2) 2 years postoperatively in the outlier TSP group. The AOFAS scores of the normal TSP group were significantly higher than those of the outlier TSP group 6 months and 2 years after the operation respectively (P ＜ 0.001, P ＜ 0.001). The post-operative outlier sesamoid was the only independent risk factor for the postoperative functional recovery (OR =1.974, 95％ CI: 1.706 - 2.211, P ＜ 0.001). Conclusions The TSP grade after the hallux valgus surgery has an important influence on the functional recovery of patients with hallux valgus. Functional recovery of TSP grade I - IV patients was better than that of the V - VⅡ patients.