One of the questions I get somewhat often is, "what is up with my piriformis, and why is it bothering me?...and will yoga fix it?" Truthfully, I don't know what's going on for you, but let's look at where the muscle is, and what its function is. One of the key things to remember is that this muscle, the piriformis, works in concert with the other deep rotators of the hip- lying beneath the gluteals, and working to externally rotate your hip and assist in abduction in hip flexion. This group of muscles attaches around the sacrum (tailbone) and attaches to the greater trochanter of your thigh bone, so essentially from pelvis to leg bone. The other muscles in that group (super and inferior gemellus, obturator internus and externus, and quadratus femoris) all play their own role in similar actions, yet the piriformis is the only muscle in that group that is directly in contact with the sciatic nerve, the largest nerve in the body running from the lower spine all the way to the foot.
Many of us have heard of, or perhaps experienced sciatica, which can manifest as numbness, tingling, burning, or other sensations in the foot, calf, and thigh. The cause of the sciatica can be more difficult to pinpoint- a lower back pathology may be the cause, such as a herniated lumbar disc, and although the lumbar nerves blend together around the piriformis, the hip rotators are not always, though sometimes, to blame. Sciatica is not actually a clear diagnosis- it doesn't tell you what the problem is, just that the nerve is being compressed somewhere from the lumbar spine all the way down to the foot. In most people, the piriformis is adjacent to the sciatic nerve, but in some people, the nerves actually pass through the piriformis itself, which is where the issues can present themselves in pirifiromis syndrome if the muscle impinges the nerve. A nerve impingement could still happen elsewhere in the leg or spine, but usually the piriformis gets the bad rap for causing impingement of the sciatic nerve. Side note, the research suggests that the piriformis is only responsible for 6% of sciatic pain!*
So then what do you do if you have sciatica or believe you have piriformis issues? I'm a big fan of seeing a medical practitioner to make sure other issues aren't present, such as a spine pathology or something else. As a yoga/pilates teacher, I can't and shouldn't diagnosis the cause of the pain, which is why it's good to seek a medical professional's opinion. But if you google "piriformis stretch," or "yoga for sciatica," you will see a plethora of suggestions. My main hesitation is that sometimes, stretching an irritated muscle or nerve will make symptoms worse, especially if it's not the culprit. Yoga poses also aren't pills to fix things- a greater awareness of what's going on in the body is critical! One of the things that has become more commonplace knowledge is that if something hurts, stretching it is not always a good solution and that lack of strength and stability may also be the issue. Some questions to ask yourselves if you are having sciatic nerve issues:
1) Are the symptoms present in both sides of the lower body?
2) When are the symptoms most present? (sitting vs standing vs lying down, etc)
3) Do any movements relieve the pain? (i.e. does walking change things)
4) Do any movements exacerbate the pain?
5) How many hours a day do you spend sitting in a chair?
Musicians (and normal people too) spend many, many hours a day sitting in a chair, often at 90 degrees of hip flexion. Even if sciatica or piriformis issues aren't present, the continued static position of the hip affects the whole body, including standing, walking, and other daily activities. Lack of hip range of motion coupled with lack of hip strength can lead to issues within the whole hip and spine complex, not just the piriformis, so start by asking yourself these questions about what's going on in the spine, hips, legs, and feet.
*By the way, there's a great blog on the whole "yoga and sciatica" conversation, and it's definitely worth a read!