A: The sound that joints make when they move can often be scary. When do we need to be concerned about these sounds? Whether or not we should ignore them is the crux of this question and our medium of exploration is asana.
It would seem that if you asked this question to a physician or other health practitioners, you would probably get an answer that sounded like this (now remember I now have my physical therapist’s hat on). Often sounds in knees are called crepitus. Crepitus may show up suddenly with no associated pain and it may be persistent every time the motion is performed. These joint noises are considered “benign” because there is no associated pain. Some theories of what causes these sounds (and the medical term is cavitation) are that when the knee joint moves there are changes in joint pressure in the synovial fluid. The changes in joint pressure cause tiny bubbles of gas to form slowly in joints. When these gas bubbles burst quickly, they make a popping sound similar to when you pop bubble wrap. The myth that states that these joint sounds will lead to arthritis is not medically proven.
Okay, so now let’s explore the sounds a bit more. Remember, the ends of the bones in the knees are covered with cartilage. This cartilage protects the joints as we bend and straighten them. If this cartilage becomes worn or frayed, the normal and smooth sensation that accompanies knee motions can become rough, leading to catches or popping sensations. If the cartilage becomes severely damaged, severe painful catches and swelling can occur.
Another cause of joint noise is the snapping of tendons or scar tissue as they are stretched slightly as they go over a prominence around the knee joint and then snap back into place making that popping sound. Again, medical opinion is that there is no harm with this knee popping as long as it isn’t causing pain, and it will not put you at risk or make you more prone to injury.
Finally, sounds in the knee may be due to small fragments of cartilage or other tissue that move freely around the joint, and these small bodies can cause complaints of popping and catching although they are most often associated with pain with movement or loss of movement due to catching.
But now let’s address this teacher’s question. She states that the student “has a lot of issues with her knees, and also has a total hip replacement.” Well, “a lot of issues with her knees” is pretty vague, but after a hip replacement it is probably that this student’s mobility has been limited for quite some time. When hips are in pain, it significantly changes how we walk and stand. Our physical abilities decline and we become much more sedentary. So we have the surgery to fix the main limiting problem but our body has to learn how to move again without the fear of causing the pain that we had for such a long time prior to surgery.
I would recommend that you first look at your student in Tadasana (Mountain pose) to get an idea how she distributes her weight on her feet and her knees and whether her kneecaps (patellas) are facing in the same directions. Looking for asymmetries in her knees and feet will help you learn what might need to be addressed in her asana practice. I also would watch her walk, and see how she moves in space and how easy and smooth her walking is. I would also assess her balance.
Of course, knowing her hip limitations and restrictions is paramount before she begins an asana practice, and if she herself doesn’t know, she may have to either give you permission to call her surgeon. or you can ask her to call herself (but be specific in the questions she has to ask). As to her particular practice limitations, I might start her practice in a chair first so she can learn how to move her body with support. By having her practice in a chair, you can figure out if moving her knees in sitting has the same effect on the knee noise as loading her knees (standing in weight-bearing positions). Next, have her progress to standing poses but only with small, partial knee bending not full bending, seeing if there is a point that no noise occurs in the movements. She can work this way until she is ready to move onto the full poses.
—Shari
