THE PHYSIOLOGICAL COST OF GAIT (PCG): A NEW TECHNIQUE FOR EVALUATING NONSTEROIDAL ANTI-INFLAMMATORY DRUGS IN RHEUMATOID ARTHRITIS

Abstract
The physiological cost of gait (PCG) provides a technique for reproducibly quantifying the physical disabilities occasioned by inflammatory joint disease. The preferred walking speed (PWS) and the physiological cost index (PCI) related to achieving that PWS are shown to be abnormal in rheumatoid arthritis (RA) and objective improvement can be demonstrated with naproxen and indomethacin, two commonly-used nonsteroidal anti-inflammatory drugs (NSAIDs). Twenty patients with active RA were studied by double-blind cross-over technique and 16 completed the two-month study. Reliable PCG data obtained in 13 patients showed statistically significant improvement in PWS and PCI with NSAID therapy. Improvement was not correlated with conventional clinical measures of joint inflammation such as pain score, articular index, haemoglobin or ESR but the trends were similar. PCG may offer a reproducible, objective method of quantifying disability and response to treatment.