A Preliminary Field Trial Evaluating the Efficacy of 4% Polyacrylamide Hydrogel in Horses with Osteoarthritis

Introduction: Polyacrylamide hydrogel (PAHG) is being investigated for the treatment of osteoarthritis. A field trial utilizing 4% intraarticular PAHG in equine joints with naturally occurring osteoarthritis is indicated to determine effectiveness. The objective of this field trial is to investigate intra-articular 4% PAHG in horses with naturally occurring osteoarthritis.

Materials and Methods: Horses were selected for inclusion in the study based on a lameness examination including intra-articular localization and radiographic examination. Twenty-eight horses that met study criteria were included in the primary outcome evaluation. For primary outcome, success was defined as at least 1 grade decrease in lameness and/or a combined reduction of at least 3 grades among the scores for pain, range of motion and joint swelling from treatment to day 45.

Results: There was a significant (p < 0.001) decrease in median (range) lameness score from 2 (1 to 4.5) to 1 (0 to 3) with 23/28 (82%) of the horses improved based on study criteria. Additionally, 21/28 (75%) of the horses met study criteria for success at day 90. Throughout the study period there were 43 injections of PAHG, which included eight horses that had the material administered two times and there were no adverse events recorded in any horses.

Discussion/Conclusion: PAHG was effective in decreasing lameness in naturally occurring osteoarthritis in horses. The limitation of this study was that there was no control group and study follow-up was a maximum 90 days.

Acknowledgement: This study funded by Nucleus Regenerative Therapies.

No conflict of interest has been declared by the author(s).