Eleven out of 24 patients with systemic sclerosis had radiological features of inflammatory polyarthritis. Juxta-articular osteoporosis was present in 9 patients, erosions in 5 and loss of joint space in 6 patients. Only one patient had a positive rheumatoid factor. Titres of rheumatoid factor, anti-nuclear factor, and plasma viscosity were comparable in patients with and without radiological abnormalities. Measurements of grip strength and finger-palm flexion also were similar in the two groups. However, in individual cases joint or tendon sheath disease was associated with loss of function.