Quadriceps muscle weakness

This can follow a number of causes including recent injury to the knee or thigh, aging, a period of sickness and/or inactivity, arthritis of the knee (sometimes isolated to the kneecap joint) or hip arthritis. The net result is that the quadriceps muscle does not get enough stimulation to remain strong and giving way of the knee occurs. This may be while walking or often while getting in and out of a chair or on stairs. Sometimes the knee simply feels as if it may give way.
Sometimes the weakness shows as obvious visible muscle wasting which can be measured or it may be necessary to perform a computerized muscle strength test (KinCom test).
Intensive quadriceps exercise will help this problem and should be instructed by an experienced sports medicine physiotherapist.