A Double-blind RCT of a Single Dose of Hyaluronan in the Treatment of Osteoarthritis of the Ankle

Inclusion Criteria: * To be eligible, subjects had to be at least 18 years old, not pregnant, and have pain and osteoarthritis of the ankle of at least stage 2 on the Kellgren and Lawrence scale. * Their AOFAS score had to be 90 points or less out of a possible 100 points. * Eligible subjects had to be willing to discontinue all pain medications and NSAIDs other than the rescue pain medications provided in the study. Exclusion Criteria: * Persons with systemic inflammatory condition or infection of the ankle or nearby soft tissues, * an injection of steroid or surgery on the involved joint within 6 months, * local cellulitis, rash, skin condition * diabetic or neuropathic Charcot arthropathy, * significant vascular insufficiency, * current treatment with anticoagulants, * lower extremity pain syndromes, sciatica, sprains, plantar fasciitis, * significant ankle instability or malalignment, * any known allergy to any of the components of either injection, known or suspected allergy to birds or bird products, * disabling degenerative joint disease of the ipsilateral hip, knee or foot were ineligible for the study.