My Knee Hurts. Why would I want to move it?

Posted by J Bergsten on 5th Oct 2014

Here’s an interesting fact for you. Did you know that, if you are hot, drinking a hot beverage like tea or coffee can help cool your body down? It seems counterintuitive, right? I think it does, but it is tough to argue with science, which has proven it to be true. Conversely, after a surgery, it seems logical that the best thing to do would be to keep your leg still so it won’t hurt more. However, moving your leg is one of the absolute best things that you can do for it, not only for maintaining and increasing range of motion, but also to decrease the pain in the joint.

As you well know, these surgeries are major events for your joints. During the surgery, all kinds of tissue, from skin, blood vessels, nerves, etc… are affected. Your body’s natural response is to send additional blood and fluid to the joint to help stimulate healing. But, too much of anything can be a bad thing. The extra fluid in the joint capsule causes swelling and creates extra pressure on the nerve endings, manifesting itself as pain. And no one likes to be in pain. That is where the CPM machine can be one of the best assets to your recovery.

Our joint capsules all have one position where they naturally rest. In the knee, that position is slightly bent, usually around 25 degrees of flexion. After your surgery, your knee begins to fill with fluid (your body doing its thing) and will come to rest at that position. This allows the most amount of fluid into the capsule with the least amount of pain. However, it is still painful. Utilizing a CPM will help reduce the pain further.

Do you remember the old fashioned water pumps?

When the CPM moves the joint back and forth, it creates a pumping action in the joint. The CPM creates periods of both high and low pressure. The high pressure forces the excess fluid out. This removal of fluid will cause a decrease in the swelling of the joint, lessening the pressure on the nerve endings and decreasing pain, allowing for greater range of motion and minimizing the likelihood of adhesions forming. The negative pressure draws new fluid and blood into the capsule, bathing the capsule in nutrient rich fluid, aiding the recovery process. It’s a win-win. Less swelling, less pain, greater range of motion and quicker recovery? I’d call that a win-win-win-win.