PRP and hyaluronic acid reduce synovitis in horses after arthroscopic OCD removal in Andalusian horses.

Abstract: This study was performed to evaluate the efficacy of intra-articular (IA) injections of a combination of platelet rich plasma (PRP) and hyaluronic acid (HA) on joint effusion following arthroscopic removal of OCD in the tarso-crural joint (TCJ) in young Andalusian horses. Methods: Forty Andalusian horses diagnosed with OCD of the distal intermediate ridge of the tibia (DIRT) were included in the study. Horses enrolled in this study had persisting synovial effusion after arthroscopic removal of OCD in the TCJ. A subjective semi-quantitative effusion score was adopted in the study to define the severity of synovial effusion in the affected joints. Twenty horses (Group 1) were treated with a series of 2 or 3 intra articular injections using the combination of PRP and HA accordingly to the clinical response, while no treatment other than arthroscopic OCD removal was performed in the second group of animals. The primary outcome of the study was the reduction of synovial effusion score in the TCJ affected by OCD 3 months post-operatively. Results: Twenty-five joints were treated overall in each group. Statistically significant differences were found between pre-operative and 3 months post-operative synovial effusion scores within both Group 1 and Group 2 (p < 0.001). When comparing the difference between pre-operative synovial effusion and 3 months post-operative score across groups, results showed a trend towards statistical significance (p = 0.079). The 3 months post-operative effusion score were significantly different than pre-operative effusion score between groups 1 and 2 when horses with preoperative synovial effusion scored 4 were considered (p = 0.003). No complications related to the preparation process and intra-articular infiltration of the product were observed. Conclusions: Additional treatment with PRP and HA intraarticular provides evidence of reducing synovial effusion at 3 months post-operatively following arthroscopic removal of OCD.