Knee effusions may be the result of trauma, overuse, inflammatory disease or a combination of all three. A knee with chronic inflammation or history of injury is more suseptible to further injury from trauma. Synovitis is a process of inflammation and thickening of the membrane, and may present weeks or months after initial injury. Examination of fluid aspirated from the joint, along with physical exam and history, may provide clues about the source of injury. However, since the clinical presentation of acute injury is very similar to that of chronic disorders,and because the underlying cause of synovitis may be both acute and chronic, there is little chance of ruling out the acute injury as a contributing factor for your employee's knee pain.
For a very detailed explanation of diagnostic studies, anatomy, interventions, and prognosis in knee injury go to:
http://www.aafp.org/afp/20000415/2391.html
Edited by cch771 on June 21 2006 at 10:45 AM
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