Exercising Both Sides of the Body for Arthritis Pain Relief
If I have right knee osteoarthritis, do I have to work out my left side as well?
I was recently asked by a patient why he had to work out both sides of his body in physical therapy if only his right knee hurt. I can understand some of the confusion. After all, if your right shoulder were painful and inflamed and required an injection, the medication would only be put at the site of inflammation -- in your right shoulder. You would not be a candidate for a right and a left shoulder injection! However, physical therapy, for the most part, is much different. I'll explain.
There are two basic components to physical therapy -- passive and active. In the passive component, the therapist may apply ice, heat, ultrasound, electrical stimulation, and other modalities to the painful area. For the most part, these modalities are only placed at the site of injury (there are a few exceptions that are beyond the scope of this blog). So, in this sense, physical therapy is functioning similar to an injection. The focus is on the site of inflammation with the intent on calming down the injury and returning it to its previously healthy state.
The second part of physical therapy is the active component. This is where the patient actively engages in exercises designed to stretch and strengthen muscles in order to achieve optimal biomechanics. Optimal biomechanics takes the pressure off your joints and redistributes that pressure to your muscles, where it belongs.
In therapy, specific muscles are targeted in order to focus on strengthening around the painful joint or joints. In addition, some muscles further away from the joint that may still be involved are targeted. For example, often the hip muscles and core abdominal and lower back muscles need to be addressed in people with knee pain. When the hip flexors are tight, it pulls the knee out of alignment, making the knee track abnormally. If the hip is not addressed, no matter how much work you do on the knee, the knee will still have altered biomechanics because of the hip's tightness. Similarly, addressing the core muscles will help a person stand straighter, protect the spine, and move more optimally.
For some patients with knee pain, this may be an important component to their pain. Each individual's biomechanics are slightly different and must be addressed in a unique way. Of course, in a person with knee pain, the focus is still on the knee.
An important point to stress is that the body is a kinetic chain. That means that the foot is connected to the ankle, which is connected to the knee, and to the hip, and so forth on up to the head. When a person takes a step, the force from the ground is translated all the way up the kinetic chain. If one of the points along the kinetic chain is weak, tight, or otherwise not functioning properly, that stress will have to be taken up by other members in the chain.
Another important point to stress is that symmetry is a guiding principle for optimal body biomechanics. Consider what would happen if your right knee hurt and so you only strengthened the muscles around the right knee. Your right knee quadriceps (front thigh muscles) would grow stronger, helping to take the pressure off that knee. In the short term, you might start to feel better. But as you walked more and more, the increased strength on the right side would dominate and pull you off your center, which would place an increased stress on your left side! Ultimately, you may end up with left sided pain in your knee, hip, or lower back.
In addition to the passive modalities, an advantage of structured physical therapy, as opposed to doing exercises on your own at home, is that the therapist can design a therapy program targeted to your specific needs. As you work on the exercises, the therapist can place their hands on you and give you instant biofeedback about which muscles you should be feeling and overall how to do the exercise best.