What are the specifics of the exercise program?

Initially the patient should strengthen his quadriceps isometrically, progressing to isotonic strengthening. Sometimes isokinetic exercise is necessary as well. (Details follow below.) In some patients, electrical stimulation or biofeedback may supplement and enhance the exercise program. Electrical stimulation involves application of electrodes to the thigh and an electrical current, which assures that the contraction of the muscle will be full and result in strengthening. Biofeedback involves application of electrodes with a sound (auditory) or light (visual) signal which indicates to the patient how complete the contraction is. The patient can then monitor and adjust their effort to gain fuller control over the muscle contraction. These complex techniques are reserved for more difficult cases. One should always avoid exercising through a painful “arc” of the range of motion. This is usually in the part of the arc where the patello-femoral pressure is highest, through mid-flexion.

1. Isometric Strengthening
   Lie flat on back, face up. Contract quadriceps and imagine “pushing knee down” into mattress with maximal force. These should be virtually no motion at the knee
   
2. Straight Leg Raise (Isometric)
   Lie flat on back with weight on ankle. Lift foot approximately 12" off bed keeping knee completely straight. Hold for 3-5 seconds. Count out loud. Lower leg to bed again, slowly. Repeat 15 times, 3 sets. The amount of weight on the ankle should be increased slowly from 0-20 lbs.
   
3. Isotonic Strengthening
   Once isometric exercises can be done with 15-20 lbs. comfortably, limited-range isotonic strengthening should be begun.
   
1. Terminal Extension – Sitting up on a table or a high chair, with feet dangling, weight around ankle, straighten (extend) the knee to full extension. The knee should then be bent up to 30 degrees of flexion slowly and straightened again. Each flexion-extension arc is one repetition. Perform 15 repetitions, 3 sets. This exercise should be begun with approximately 5-10 lbs. And gradually increased to 20 lbs. over several days to weeks.
   
2. Multiple Small Arc Isometrics/Isotonics – If feasible, multiple similar contractions should be performed at different angles of flexion. These should be begun isometrically and progressed to small arcs of isotonic flexion/extension.
   
3. Once #1 and #2 can be done comfortably, gradually increase to full-range isotonic strengthening. This means sitting with leg extended, and flexing all the way and extending all the way. This is not for everyone!
   
4. Isokinetic Strengthening
   People with more strenuous activities, typically athletes, sometimes need to go beyond isotonic strengthening to isokinetic strengthening. This involves usage of isokinetic machinery, such as BIODEX, where not only the strength of the muscle contraction is trained but the “speed” of contraction as well. The rate of development of force in the muscle is known as “torque”. Training to recruit the fullest possible force in the muscles in the shortest time results in reduced patellar pressure and decreased symptoms.