OBJECTIVE: The aim of this study was to investigate the effect of botulinum toxin type A injection into the adductor muscles in reducing pain and improving joint mobility and quality of life in patients affected by hip osteoarthritis. METHODS: A total of 39 outpatients, mean age 68 years (age range 41-82 years), were evaluated using the Harris Hip Score to test hip function, a visual analogue scale to measure pain intensity and the Short Form 36 (SF-36) questionnaire to assess patient well-being and quality of life at baseline, 2, 4 and 12 weeks after treatment with botulinum toxin type A. A total of 400 U of botulinum toxin type A (Dysport) was injected into the adductor longus muscle and the adductor magnus muscle. RESULTS: The Harris Hip Score increased significantly after 2, 4 and 12 weeks (df 3, chi2 = 45.1; p < 0.0001). A significant decrease in pain intensity was detected at all the follow-up visits, after 2, 4 and 12 weeks (df 3; chi2 = 27.8; p < 0.001). The SF-36 score was significantly higher 4 and 12 weeks after treatment. At each evaluation visit a significant correlation was detected between decreased pain and improved hip mobility. CONCLUSION: Botulinum toxin type A induced a reduction in pain, indicating that this might be an innovative, less invasive treatment in patients affected by severe hip osteoarthritis, with remarkable effects on the clinical management of this disease.