Exercise is the necessary method to restore the normal function of all the painful knee syndromes, as a result of overuse, injury or surgery.
If your Orthopedist advises you to start exercising, then your rehabilitation program should include the following goals.
1. RESTORE FULL RANGE OF MOTION
Normal function of the knee during the activities of daily living and in sports, requires that the knee can fully straighten and bend as much as possible, without pain.
When you bend and stretch your knee into extension to increase the range of motion, it is normal to feel a slight discomfort at the limit of the available range of motion, provided that it does NOT last. Your body will adapt and gradually the range of motion will come back to normal.
2. QUADRICEPS MUSCLE ACTIVATION AND STRENGTHENING
Our knee can not function properly without an optimal activation of the quadriceps muscle. When our knee hurts, the Central Nervous System decreases the activation of the quadriceps muscle, as a protective reaction. This protective response, in conjunction with the fear-avoidance strategy to put less weight on the painful knee, causes a reduction in the strength of the quadriceps muscle. As a result, the knee loses its ability to absorb the loads of our body.
You should start strengthening the knee with “Open Kinetic Chain” exercises. OPC exercises are performed WITHOUT the use of our body weight. Initiate the exercises in the painless range of motion with minimal resistance and work your way up to a wider range of motion, adding resistance as the muscle’s output increases.
3. GLUTE ACTIVATION
While you are working on the range of motion and quadriceps activation, you can start the glute activation exercises. The glute muscles are important muscles for two reasons.
a) They hold the pelvis level during the single leg stance (ie when we walk, run, go down stairs, etc.),
b) They also keep the knee aligned between the hip and the ankle. When the glutes are inactive and weak, the knees fall inwards and the condition is called “dynamic valgus”. Dynamic valgus is a leading cause of anterior knee pain and knee injuries in sports.
Below are some of the most important exercises for the glutes and can be performed easily on a mat.
4. MOTOR CONTROL EXERCISES USING THE BODY WEIGHT
When you have achieved a satisfactory knee range of motion and have quite strong quadriceps and gluteal muscles, it’s time to begin the “Closed Kinetic Exercises”, with the use of the body weight. Body weight exercises are functional exercises and prepare your knee to meet the demands of daily activities and sporting activities. Your functional goals decide the type and the intensity of the body weight exercises.
As noted above, the proper alignment of the knee joint, between the hip and the ankle joints, is very important. However, keeping the knee properly aligned is not only a matter of strength. It is a motor control task, that needs to be retrained, the same way as a dance move.
These exercises should be performed in front of a mirror, to enable the self-correction of possible errors during execution. Special attention must be paid in the knees staying apart during squatting, side to side movements etc.
5. PROPRIOCEPTION AND BALANCE EXERCISES
When your goals include the participation in sporting activities, you should perform exercises that prepare the knee to adapt in a changing and unpredictable environment. To meet this purpose we use unstable surfaces (balance boards, bosu etc.) and single leg exercises, so you can gradually improve your balance and dynamic stability of the whole lower extremity.
Even if you don’t participate in sporting activities, you should perform balance and weight shifting exercises, so you will adopt a stable and economic gait pattern, with proper activation of all muscle groups.
Alex Karagiannidis, MSc., Dip.MDT., BSc(Hons) Physiotherapy
Active Physiotherapy Solutions