Simple Summary
Dogs with hip osteoarthritis often have joint pain and decreased mobility, but it can be difficult to know whether a treatment is truly helpful. Using several assessment tools may provide a more complete picture of improvement after treatment. This study compared meloxicam, two marine-based fatty acid products, a combination of meloxicam with one marine-based product, and placebo treatment in client-owned dogs with naturally occurring hip osteoarthritis over 4 weeks. We assessed weight bearing on the affected hindlimb, veterinarian-assessed orthopedic status, owner-reported mobility and pain-related daily activity, and short-term blood safety results. Average weight-bearing measurements did not clearly differ among treatment groups. However, dogs receiving meloxicam were more likely than placebo-treated dogs to reach a conservative individual-dog weight-bearing improvement threshold at Week 4. Combination treatment showed improvements in owner-reported mobility and pain-related daily activity. One marine-based product showed owner-reported mobility improvement, whereas the other showed owner-reported improvement in pain-related daily activity. These owner-reported findings were not matched by clear objective evidence of better weight bearing. No consistent group-level safety concern was detected in blood test results, although individual clinically relevant events occurred. These findings may help veterinarians and owners judge treatment response using complementary tools rather than a single measure.
Abstract
Canine hip osteoarthritis (OA) requires multidimensional assessment. This randomized, double-blind, placebo-controlled trial evaluated 4-week treatment with meloxicam, PCSO-524, EAB-277, meloxicam plus PCSO-524, or placebo in 203 client-owned dogs with naturally occurring hip OA. The principal outcome was index-hindlimb peak vertical force (PVF) measured by force-plate gait analysis. Secondary outcomes included PVF responder status, orthopedic assessment score (OAS), Liverpool Osteoarthritis in Dogs (LOAD), Canine Brief Pain Inventory (CBPI), and safety assessments. The primary baseline-adjusted mean PVF analysis did not demonstrate treatment superiority among groups. A secondary responder analysis using an analysis-stage >5%BW PVF threshold showed that meloxicam had a nominally higher Week 4 responder probability than placebo (relative risk = 4.000; 95% confidence interval, 1.223 to 13.079; p = 0.022), interpreted as supportive rather than confirmatory. Within-group score reductions were observed in LOAD and CBPI pain interference for the combination group, LOAD for PCSO-524, and CBPI pain interference for EAB-277. OAS did not change significantly within any group. Between-group differences in LOAD and CBPI changes were not significant. No consistent group-level laboratory safety concern was detected. These findings support multidimensional assessment while emphasizing that secondary results do not establish treatment superiority.