The Additional Effect of Hallux Valgus Correction on Runners With First Ray Instability and Patellofemoral Pain Syndrome

Inclusion Criteria: * High physical activity level (running at least 5 times/week and at least 2 hours/time) * Presenting anterior/retropatellar knee pain in the past 6 months * At least two of the following activities provocated symptom: Prolonged sitting, ascending and/or descending stairs, squatting, kneeling, running, limping * Not having any pathologies of knee joint (ligament tear, menisci injury, patellofemoral joint dislocation, tendinitis, bursitis…etc.) * With hallux valgus angle\>15° * With 1st metatarsophalangeal joint instability * 20\~40 y/o Exclusion Criteria: * Lower extremities osteoarthritis * Systematic diseases such as rheumatoid arthritis, systemic lupus erythematosus, DM…etc. * Lower extremities fracture history * Surgical history of lower extremities * Neurological pathology that would interfere with gait * Hallux could not be corrected to neutral through passive correction * Low back pain and/or sacroiliac joint dysfunction in the past six months * Excessive femoral anteversion