Piriformis Syndrome
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A Real Pain in the ….
A while back I noted that very often I will be visited by a runner complaining that his or her “sciatica is acting up.” Generally, what they are saying is they have some pain in the back of the thigh, maybe some in the buttock, low back or even into the calf. Sciatica, by definition, is an inflammation or irritation of the sciatic nerve, the largest nerve in the body, which originates in the lower spine in the form of five separate nerve roots which join together and traverse the buttock and descend into the lower limb all the way to the toes. The problem is, sciatica is a vague term that doesn’t really tell us very much about the underlying reason for these symptoms since there can be several explanations for them.
Some of the possible causes of this ailment which reviewed then included sacroiliac joint dysfunction, lumbar spine arthritis or herniated discs, chronic hamstring strains and a rather esoteric-sounding problem called the piriformis syndrome, which we want to look at in more detail now.
The piriformis muscle is a relatively large structure found in the buttock, originating on the sacrum (the lower part of the spine, or tailbone) and crossing over at a slightly downward angle to the outside of the hip, attaching to the outer portion of the upper thighbone (femur). Its function is to laterally rotate and extend the hip joint. It is only one of several muscles in the buttock which, as we’ve said, is an area through which the sciatic nerve passes, but the piriformis has been singled-out as a potential cause of sciatica because anatomists have found that in a fair number of people, all or part of the sciatic nerve goes directly through this particular muscle. (The exact percentage of people is unknown — studies vary widely with some experts reporting 20% and others as many as 60%!)
The speculation is that in these subjects, a tight piriformis muscle will “squeeze” the nerve, causing irritation and subsequent pain. Runners, of course, would be more likely to have a tight piriformis since they would be using it more often and more intensely, especially during the push-off phase of gait when hip extension and lateral rotation are needed most, but theoretically anyone could experience this problem really if posture and biomechanics of walking are abnormal.
Is it real? Does piriformis syndrome really exist? Well, the fact that we call it a syndrome — which in the medical field is a code word for “we don’t really know exactly what it is or know for sure what really causes it” — tells us a lot. It seems reasonable that the piriformis, like any muscle, can become overused and painful, especially with running. But, like any muscle, this irritated muscle can cause radiating or referred symptoms which would mimic sciatica pain while there may not necessarily be any actual injury to the nerve itself. Or, conversely, there are other potential causes of nerve inflammation in the buttock with no involvement of the piriformis muscle. My favorite example is something actually designated in the medical literature as “fat wallet syndrome,” which is found most often in long-distance drivers (truckers, salesmen). The prolonged pressure of a billfold full of cash and credit-cards on the sciatic nerve is a not-infrequent cause of sciatica. (The cure, of course, is for me to relief the patient of the offending object…)
Whatever the real culprit, runners with sciatica symptoms with clear pain and tenderness in the upper and outer buttock can treat this initially as if it were piriformis syndrome, since the following remedies are easy to try and usually result in quick success if, in fact, this is the problem. The first measure is an exercise to stretch the piriformis muscle by sitting on the floor with both legs out straight, then bringing the foot of the affected (say, right) side over to the outside of the other (left) knee. Then pull the right knee with your hands across your body toward the left shoulder until you feel a gentle pull in the right buttock. Hold this position for 90 seconds, release, rest 30 seconds and repeat. The other treatment to try is trigger point massage or compression of the muscle itself. (Unless you suspect you have “fat-wallet syndrome,” in which case call and make an appointment with me!)
If these self-treatments do not result in some improvement within a week, the cause of your sciatica may be elsewhere, in which case you should consider seeking the help of a professional.