Abstract
The purposes of this article are 1) to provide an updated summary of some aspects of research into osteoarthritis and 2) to stimulate physical therapy inquiry on its causes, effects, and treatments. The current literature concerning the pathological changes associated with osteoarthritis is reviewed in the context of specific joint tissues (ie, articular cartilage, bone, synovial membrane, capsule and capsular ligaments, muscle, and nerve). Correlations are drawn between the pathological effects of osteoarthritis on these tissues and commonly observed clinical changes. Gaps in the current research literature are discussed, and areas needing further research are highlighted.