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Knee flexion means bending your leg at the knee joint, reducing the angle between your lower leg and upper leg.
Arthritic and non-arthritic joints may develop âarthrofibrosis.â In this condition the knee fails to straighten fully. This is called a flexion contracture. Persons with this condition walk with the knee bent to varying degrees. The photo below shows a patient with a large flexion contracture in the right leg. Although they can straighten out their left leg so that it lies flat on the table, this is a straight as the right leg can get. The angle that the knee makes can be measured and is labeled as the degrees of the flexion contracture. The higher the number, the more bent the knee is. Walking with a bent knee is an abnormal stance. It causes increased pressure and âwear and tearâ on the knee while walking, especially on the knee cap. The end result is pain and disability. The worse the flexion contracture, the more rapidly the symptoms appear. But even mild flexion contractures can cause disability if they are left untreated. One study by Riddle found that over three years, for every degree of flexion contracture present, the risk of having a knee replacement increased 6%. Treatment of Flexion Contractures