Midfoot and forefoot osteoarthritis

Background: Foot osteoarthritis (OA) is linked with chronic foot pain and functional impairment. Objective: To review the current knowledge on midfoot and forefoot OA. Methods: PubMed, CINAHL, PEDro, and the ISI Web of Science databases (1950-2013) were searched for keywords: foot OA, midfoot OA, forefoot OA and metatarsal OA. The search was limited to reports in human subjects and English language. Published cohort, cross-sectional studies and clinical trials relating to epidemiology, clinical features, functional impairment, risk factors and treatment were included. Results: We found heterogeneity in the design, radiographic views and grading systems used among studies. Most of the literature focused on radiographic OA, being the prevalence between 0.1% and 61%, depending on gender, age and joint evaluated. The age and female gender were the main associated factors, whereas structural (bone length) and mechanical factors (hypermobility, altered tarso-metatarsal stress, etc.) seemed to be related. Various treatments are widely used, i.e. physical therapy, orthotics, steroid injection, analgesics and arthrodesis. However, scarce research supports their efficacy. Conclusion: Most of the current knowledge comes from observational and small case-control studies. Future population-based studies as well as controlled studies are essential to understand the risk factors and to evaluate the effectiveness of treatment options.