Characterization of osteoarthritis in cats and meloxicam efficacy using objective chronic pain evaluation tools

This study aimed to characterize osteoarthritis (OA)-related chronic pain and disability in experimental cats with naturally occurring OA. Peak vertical ground reaction force (PVF), accelerometer-based motor activity (MA) and the von Frey anesthesiometer-induced paw withdrawal threshold were used to define OA and to test the efficacy of meloxicam. A diagnosis of OA was based on radiographic and orthopedic examinations. Cats with OA (n=39) and classified as non-OA (n=6) were used to assess the reliability and sensitivity of the parameters to assess OA over 3weeks while being administered placebo medication. A randomised parallel design study was then used to investigate the effects on OA of daily oral meloxicam treatment for 4weeks at different dose rates (0.025mg/kg, n=10mg/kg; 0.04mg/kg, n=10; 0.05mg/kg, n=9), compared to cats administered a placebo (n=10). The test–retest repeatability for each tool was good (intra-class correlation coefficient ⩾0.6). The PVF and the von Frey anesthesiometer-induced paw withdrawal threshold discriminated OA (P