Degenerative Changes of Joints

Abstract

Degenerative changes of peripheral joints appear most frequently in the lower extremities, and are sometimes observed primarily and distinctly in the articular surface of the patella [806]. The cause of these changes may lie in injuries or mechanical disuse, particularly in young adults who do not manifest changes in any other joint. Not only are unequivocal traumata adduced as causes of this condition but, as Buedinger [210] noted, more commonly mechanical stresses associated with vertical pressure and tangential friction. Such stresses are produced by appositional tenseness of the contracting quadriceps muscle. In this context, Karlson [854] described cases in which alterations in the patellar articular cartilage were observed secondary to repeated minor traumata. These directly posttraumatic alterations are classified as idiopathic chondropathia patellae due to the nature of the observed pathological changes.