Musculoskeletal manifestations in polymyalgia rheumatica and temporal arteritis

Objective-To evaluate the incidence and characteristics of musculoskeletal manifestations in polymyalgia rheumatica (PMR) and temporal arteritis (TA). Methods-The records of 163 cases of PMR or TA diagnosed over a 15 year peri od in one area of Spain were reviewed for the presence and type of musculos keletal manifestations. Results-Of 163 patients, 90 had isolated PMR and 73 had TA. Eighteen of the 90 patients (20%) with isolated PMR developed distal peripheral arthritis either at diagnosis or during the course of the disease. When it occurred, synovitis was mild, monoarticular or pauci-articular, asymmetrical, transie nt, and not destructive. Other distal manifestations observed in these pati ents were carpal tunnel syndrome and distal extremity swelling with pitting oedema. In all cases these manifestations occurred in conjunction with act ive PMR. As expected, PMR was the most frequent musculoskeletal manifestati on in patients with TA, occurring in 56% of cases. On the contrary, only 11 % of patients with TA developed peripheral arthritis. An important finding was that peripheral arthritis in these patients appears to be linked only t emporally to the presence of simultaneous PMR and is not observed in its ab sence. Distal extremity swelling or defined polyarthritis were not observed . Conclusion-The spectrum of distal musculoskeletal manifestations of PMR in our series is similar to that reported in other populations. By contrast, d istal musculoskeletal symptoms are uncommon in TA. The almost complete abse nce of distal musculoskeletal manifestations in patients with pure TA sugge sts different mechanisms of disease in PAM and TA, supporting the view of t wo separate conditions or one common disease in which host susceptibility i nfluences the clinical expression.