The joint capsule and joint laxity in dogs with hip dysplasia.

Present knowledge of the complexity of joint diseases makes it difficult to investigate the causes and early pathogenesis of canine hip dysplasia. Clinical signs of canine hip dysplasia including joint laxity may be a result of primary or secondary alterations of the joint. We already know that joint laxity is related to effusive synovitis (ie, accumulation of synovial fluid) and to other primary collagenous diseases. Canine hip dysplasia may be a third collagenous disease associated with joint laxity. This paper summarizes some of the studies that investigated the relationship between joint laxity and a defect in collagen metabolism and the influence that alterations in transsynovial flow have on joint laxity.