Clinical and Radiographic Outcomes of Foot Orthosis for Hallux Valgus

Abstract

Category: Bunion Introduction/Purpose: Nonoperative care, which is safer and costs less than operative treatment, is the first-line treatment for hallux valgus. Despite numerous studies have reported results of operative treatments, little information is available on the efficacy of nonoperative treatments for hallux valgus. Foot orthosis, or shoe insole, is one of the most widely used nonoperative treatments. Torkki et al. compared orthotic treatment with operative treatment in a randomized controlled trial, however the subjects were patients who planned to undergo hallux valgus surgery, and thus the patient background was different from clinical setting. It is also controversial whether orthotic treatment can prevent the progression of toe deformity. This prospective one- year follow-up study was conducted to evaluate clinical and radiographic outcomes of foot orthosis for painful hallux valgus. Methods: Patients were recruited prospectively at the foot and ankle clinic of our university hospital from 2011 to 2014. Inclusion criteria were patients over 20 years old, with hallux valgus angle (HVA) greater than 20 degrees, and having a painful hallux and/or forefoot. Patients were informed of both surgical and orthotic treatments regardless of the severity of deformity, and those who selected orthotic treatment were included. One certified orthotist made custom-made total contact insoles, and patients were instructed to wear them as long as possible. Clinical evaluations were performed at baseline, 6 and 12 months. The evaluations included visual analog scale (VAS) for pain, American Academy of Orthopaedic Surgeons (AAOS) foot and ankle score, and SF-36. Patients also reported mean hours a day to wear the orthosis, and treatment satisfaction using VAS at 6 and 12 months. HVA and intermetatarsal angle were measured with the radiographs at baseline and 12 months. Results: Of 158 patients visiting the clinic, 65 patients selected orthotic treatment, and thus included in this study. Mean pain VAS was 48.1 at baseline, and it decreased significantly at 6 months (27.7, p < 0.001). However, it increased slightly at 12 months, although it was still lower than the baseline value (30.6, p=0.002). The AAOS Core Scale was 36.1 at baseline, and it improved significantly at 6 months (42.3, p < 0.001). However the effect of orthosis diminished at 12 month (39.8, p=0.2). The same trend was found for the bodily pain of the SF-36. Patient satisfactions were 54.1 and 54.7 at 6 and 12 months, respectively. The mean HVA and intermetatarsal angle were 41.1 degrees and 17.4 degrees at baseline, and they did not change at 12 months. Conclusion: Wearing total contact shoe insole improved pain and functional outcomes for patients with painful hallux valgus, and the treatment effect lasted for at least 12 months. However, the effect was maximal at 6 months, and diminished slightly at 12 months. Therefore a longer follow-up study is necessary to assess how long the effect will continue. Additionally, the orthotic treatment in this study had no effect on hallux valgus deformity over a 12 month period.