Joint Instability

The knee is commonly affected in OA. It is important to localize the symptoms because the joint has three separate articulations. Knee OA is associated with pain, tenderness, crepitus, and limited range of motion. Limitedjointmotion occurs from loss of articular surfaces, muscle spasm, capsular contracture, or mechanical blockage secondary to osteophytes (bony enlargements). Weakness or instabihty (the joint gives way ) is frequently noted by patients with knee OA. Such joint instability may lead to decreased activity and muscle atrophy. 

Balasch H, Schiller M, Friebel H, Hofftnann F (1999) Evaluation of anterior knee Joint instability with the rolimeter. A test in comparison with manual assessment and measuring with the kt-1000 arthrometer. Knee Surg Sports Traumatol Arthrosc 7 204—208... 

Mow, V. C., Howell, D. S. and Buckwalter, J. A. (1990) Structure-Function Relationships of Articular Cartilage and the Effects of Joint Instability and Trauma on Cartilage Function, in Cartilage Changes in Osteoarthritis (ed. Brandt, K.D.), Indiana University Press, Bloomington, IN. 

The diagnosis of joint instability basically relies on plain films. In some instances, however, the complex anatomy of joints and surrounding structures... 

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