67 patients with knee osteoarthritis (OA) scheduled for arthroscopic debridement were randomized to treatment with or without subsequent, postoperative intra-articular injections of hyaluronic acid (HA) injections. The purpose of the study was to evaluate any possible effect of postoperative HA injections on knee pain and functional disability over 24-week follow-up. Outcomes were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain and Function subscores. Results at 6 weeks demonstrated significantly greater reduction in mean WOMAC Function subscore in the HA group compared to the control group, though no significant differences were noted at 12- or 24-week follow-up. No significant difference between groups were noted in reduction in mean WOMAC pain subscore at any follow-up.