Capsular compliance and pressurevolume relationships in normal and arthritic knees

This study * of joint capsular compliance was undertaken in an attempt to assess objectively the effect of rheumatoid arthritis on the integrity of the joint capsule and associated ligaments. Joint instability and subluxation in progressive rheumatoid disease may result from damage to these structures through granulomatous invasion and distension by intra-articular effusion. Alteration in the compliance of the joint capsule and associated ligaments might be important as being early evidence of significant tissue damage. Changes in the properties ofjoint tissues which can be related to joint symptoms are of theoretical importance. Urayama (1956) investigated the relationship between pressure and volume after saline was injected into the knee joints of 162 patients and normal volunteers. He found significant differences between normaljoints and thosejoints with symptoms arising from injury or disease. Jayson and Dixon (1970a, b, c) confirmed Urayama’s findings (1956) of altered pressure-volume relationships in knee joints of patients with rheumatoid arthritis, and discussed the possible pathological effects of persistently increased intra-articular pressures. in the present study the observations of Urayama (1956) and of Jayson and Dixon (I 970a, b, c) have been extended and the results published by these authors compared wit