Evaluation of an intra-articular carboxymethylcellulose crosslinked hydrogel in horses with osteoarthritis

Numerous treatment strategies have been proposed to manage osteoarthritis (OA) in sport horses. Carboxymethylcellulose (CMC), is used in veterinary medicine for various purposes.

This study aimed to assess the efficacy of a CMC hydrogel in reducing clinical lameness in horses with OA affecting joint. The hypothesis was that intra-articular CMC would produce a sustained reduction in lameness compared to a control treatment.

Thirty client-owned horses diagnosed with OA-related lameness in the metacarpophalangeal joint were enrolled. Horses were randomly assigned to two groups: the treated group (n = 16) received a single intra-articular injection of CMC hydrogel (3 ml/joint); the control group (n = 14) received 12 mg/joint of triamcinolone acetonide (TA) and 20 mg/joint of hyaluronic acid (HA). Lameness was evaluated at baseline and at 15, 30, and 90 days using a standardized AAEP scoring system. Treatment success was defined as a reduction of at least one lameness grade without additional therapy. Statistical analysis included the Kruskal-Wallis test and Chi-Square test; significance was set at P < 0.05.

At 90 days, 12/16 horses (75%) in the treated group achieved success (mean score 1.3 ± 0.6), compared to 1/14 horses (7.1%) in the control group (mean reduction 0.2 ± 0.4; P = 0.001). At 15 days, 3/15 CMC horses (20%) improved vs. 13/14 controls (90%). At 30 days, success was 75% in both groups.

Intra-articular administration of CMC hydrogel provided a delayed but longer-lasting improvement in lameness compared to corticosteroid and HA treatment.