Themes > Science > Life Sciences > General Biology > Physiology > Human Body > Muscles Menu > The Butt > Piriformis

Piriformis (low back, hip, sciatic, leg pain):
Work on piriformisPiriformis originates on the sacrum and inserts on the medial surface of the head of the femur. It is the principal lateral rotator of the hip. The sciatic nerve may pass under or through the piriformis, causing entrapment. Much sciatic pain is caused by the piriformis, as well as restless leg syndrome. Its trigger points typically refer into the leg, the hip, and the low back. See below.


Piriformis pain referral zone:

Piriformis pain referral zoneTranslation: "Piriformis" means "pear-shaped." This muscle attaches to the side of the sacrum, which is the wide, flat bone at the base of your spine just above your tailbone. It lies under the large butt muscle (gluteus maximus) and goes across the buttock to attach to the top of the thighbone. Its main job is to rotate the leg outward, but it also helps to hold the hip in joint when it's bearing weight. Your sciatic nerve, which is the nerve that goes down the back of your leg, passes under or through this muscle, so tightness in the piriformis can cause sciatica, which is pain down the back of the leg. It can also cause what's called "restless leg syndrome." Trigger points in this muscle can cause pain in the back of the leg, the hip, and the low back.

Observations on Piriformis
There are six deep lateral (external, outward) rotators of the hip, all buried deep in the buttock under the gluteal muscles, and piriformis is the prime mover, the Head Honcho, the top banana (see below for the others). Its principal job as far as actions are concerned is to rotate the hip -- and therefore the leg -- outwardly. This makes it a key muscle for ballet dancers, of course, because they are required to "turn out" virtually all the time in classic ballet. Of all the ballet dancers I have worked on, from students at North Carolina School of the Arts and Wake Forest University to long-time faculty members at those institutions, I have never found one that didn't have a tight piriformis -- so much so that I have taken to calling the condition "ballerina butt," which amuses my middle-aged clients who share this condition, and many do. It's perfectly understandable why ballet dancers would have "ballerina butt," but why do so many other folks who have never done a pirouette or a grand jete in their lives?

We think of muscles mostly in terms of their specific actions, but I have found that most myofascial problems come not so much from these clear and specific actions, which may result in well-defined injuries that don't take a lot of detective work to trace, as from their collateral but very important work in supporting and stabilizing and balancing and compensating. If you look at the hip joint on a skeleton, it looks like it wants nothing more than to go flying apart at the slightest shift of weight. And yes, there are certainly ligaments holding it in place, but they aren't strong enough alone to do the job, as is clear when you think about the incredible demands we make of our hips. There are a number of muscles attaching to the head of the femur, but few are so well-placed to hold it firmly in its socket as the lateral rotators -- the biggest and strongest of which is piriformis. So however much work a ballerina's right piriformis may be doing when she lifts her right leg, turned out fully, straight away from her body, her left piriformis is actually working much harder to keep her left hip in joint while it supports her full weight.

Now, the reason this affects all of us non-ballerinas, even the couch potatoes, is that most people do not stand with their weight evenly distributed between our two legs. If you observe both yourself and others closely, you'll notice that almost everyone tends to stand with the weight shifted to one leg or the other. And that means piriformis is working overtime. (For most people, this tendency is directly related to a general postural imbalance, and cannot be corrected by voluntary efforts. It is, however, correctable through postural alignment therapy.)
Another common situation that causes or aggravates problems in piriformis occurs in driving, especially long distances. One of the worst things you can do to a muscle is to leave it in a shortened position for a long period of time, and since most people tend to drive with their knees apart, thus keeping the hips outwardly rotated, that's what happens to piriformis. That's one reason so many people experience low back or leg pain after long driving. This is just one more reason to stop frequently, even if only to walk once around the car.

Trigger points in piriformis tend to radiate pain over the buttock and refer it down the leg, as pictured above, but there is another special problem that it can cause. The sciatic nerve, which innervates the back of the leg, runs under, over, or through piriformis, or even some combination of those, depending on how your neurons developed. This means that a tight piriformis can produce symptoms of what is traditionally known as sciatica, causing intense pain all the way down the back of the leg into the foot. Piriformis syndrome can even affect the groin, the genitals and the rectum as well. And I am convinced from professional and my own personal experience that piriformis is the principal cause of what is known as "restless leg syndrome," which is an indescribable sensation requiring compulsive movement of the legs and feet, particularly in bed at night. I have eliminated this condition in myself, and taught several patients to eliminate it, by active stretching of piriformis.

Instructions for Active Stretch of Piriformis: .
STANDING (less effective, but easier in the supermarket):      Holding onto something for support, raise the straight leg a few inches off the floor and rotate the whole leg from the hip -- not just the foot -- so that the toes are pointing toward the other leg. Hold that position for ten seconds. If possible, rotate it further and repeat. Remember that active stretching requires that the stretch be done by your own muscles with no outside help.

LYING DOWN (more effective, and can be done before going to sleep at night):     

 Lying face down, bend your knee at a right angle so that your lower leg is pointing straight up. Now rotate your leg so that your foot moves outward, away from you. When you reach maximum stretch, hold it for ten seconds.

A possible complication in stretching piriformis is that there are other muscles that may restrict rotation before piriformis is stretched, such as sartorius. If you feel a pulling at the upper, outer front of your thigh, this is what's happening. It may be that you will need professional help in releasing these muscles before you can effectively stretch them on your own.

Other Deep Ltheral Ritators Of The Hip:

  • Superior gemellus
  • Obturator internus
  • Inferior gemellus
  • Obturator externus
  • Quadratus femoris


Information provided by: http://danke.com