EFFECTS OF INTRAVENOUSLY ADMINISTERED SODIUM HYALURONATE ON EQUINE CARPAL JOINTS WITH OSTEOCHONDRAL FRAGMENTS UNDER EXERCISE

The effects of osteochondral fragmentation and treatment with intraven ous sodium hyaluronate on carpal joints of 12 horses were evaluated. A ll horses had an osteochondral fragment created in one middle carpal j oint. Six of the horses were treated with 40 mg of sodium hyaluronate, and the other six were treated with saline once a week for three week s. All horses underwent treadmill exercise for 56 days. Synovial fluid samples were evaluated from both middle carpal joints during the stud y. All horses were euthanized 72 days after surgery, and synovial memb rane was obtained for histologic evaluation. Articular cartilage sampl es were also obtained for determining glycosaminoglycan metabolism. Ho rses treated with sodium hyaluronate were less lame, had significantly better synovial membrane histologic scores, and significantly lower c oncentrations of prostaglandin E(2) and total protein within synovial fluid. Intravenous sodium hyaluronate treatment appears to alleviate t he signs of lameness by reducing synovitis.