Synovial fluid and clinical changes after arthroscopic partial synovectomy of the equine middle carpal joint.

This study focuses on assessing the changes in synovial fluid and related clinical parameters after an arthroscopic partial synovectomy, a surgical procedure often performed on horses’ middle carpal joint. The study concludes that this procedure doesn’t cause significant lameness and leads to similar signs of synovitis as seen in arthroscopic lavage alone.

Methods

• Twelve horses underwent an arthroscopic partial synovectomy in the study. The surgical procedure was performed using a 7mm motorized synovial resector placed into each middle carpal joint.
• Arthroscopic synovectomy was performed randomly on one middle carpal joint of every participating horse, while the opposite joint was lavaged and served as a control group.
• All horses were examined for lameness and monitored for changes in the synovial fluid at four specific periods: before the surgery, and after 8, 14, 21, and 28 days post-operation.

Results

• No significant differences were observed in the lameness variables between the treated and control legs, indicating that the surgical procedure did not have a significant impact on the lameness variables.
• Increased measurements of middle carpal and carpometacarpal joint circumference were recorded for a duration of 4 weeks post-operation.
• Synovial fluid’s specific gravity, pH, total protein, albumin concentration, and alpha-1-, beta- and gamma-globulin concentrations significantly rose at the 8 and 14-day marks post-operation, in both treated and control middle carpal joints.
• No substantial differences were identified between treated and control middle carpal joints regarding color, clarity, pH level, mucin clot formation, total protein, albumin, and globulin fractions, at any given time.

Conclusion

• The arthroscopic partial synovectomy procedure did not cause significant lameness in the horses.
• Both the treated and control groups showed similar levels of synovitis, a condition indicating inflammation of the synovial membrane. Hence, the study suggests that the inflammation following the synovectomy was indistinguishable from that associated with arthroscopic lavage alone.