Piriformis syndrome is literally a pain in the backside. It’s a condition that can affect anyone, but it’s more common in women and in runners. Along with buttocks pain, it can also cause discomfort in the lower back. In fact, between 5 and 36% of cases of lower back pain are due to piriformis syndrome. What causes this uncomfortable condition and what can you do about it?
What is Piriformis Syndrome?
The piriformis muscle is a small muscle that lies underneath the biggest muscle in the lower body, the gluteus maximus. The piriformis connects the last vertebrae, or bone in your spinal column, to the top of your leg. From this position, it helps your hip rotate outward and stabilize your body when you stand and walk. The piriformis muscle travels over the sciatic nerve, one of the biggest nerves in the body. The sciatic nerve extends from the tip of the spinal cord down the back of the thigh. Pressure or injury to the sciatic nerve is a common cause of back and buttocks pain. For example, a herniated disc can press on the sciatic nerve and trigger lower back pain.
It’s possible for the piriformis muscle to press on the sciatic nerve too. That’s what experts believe happens with piriformis syndrome. Due to the close proximity of the muscle to the sciatic nerve, the muscle can, under certain circumstances, press on the nerve and cause pain in the buttocks and leg.
Why would the piriformis muscle place pressure on the sciatic nerve? Injuring the buttocks or straining the piriformis can be the event that brings it on. When the piriformis muscle is strained, scar tissue may build up around the muscle and impinge on the sciatic nerve. Runners are prone toward it because the repetitive movements of running can irritate or strain the piriformis muscle. It’s also more common with downhill running as eccentric, or lengthening, contractions of the muscles in the legs are more likely to irritate the piriformis than concentric contractions.
Other risk factors for piriformis syndrome include a history of a lower back, hip, or buttocks injury. Also, surgery, scoliosis, and a significant difference in leg length between the two sides of the body are risk factors. Prolonged sitting makes you more susceptible as well. So, office workers and runners are both at higher risk of developing piriformis syndrome. Certain foot problems increase the odds of developing piriformis syndrome as well, probably because they alter the alignment of the posterior chain and place added strain on the muscle. Wearing high heels frequently can also throw off body alignment and irritate the piriformis muscles. Some literature also suggests that vigorous exercise boosts the risk.
How Do You Know if You Have It?
The pain of piriformis syndrome usually comes on gradually and worsens with prolonged sitting. The discomfort becomes more pronounced with time and begins to radiate down the back of the leg, with the pain sometimes extending as far as the foot. These are all symptoms you can see with a herniated disc too. That’s why it’s important to get the symptoms checked out and get a proper diagnosis. It can progress to the point that it’s hard to bear weight on the affected side.
What Can You Do About Piriformis Syndrome?
At one time, experts routinely recommended stretching the piriformis muscles. The idea was that with piriformis syndrome the piriformis muscle is tight and contracted and stretching will help elongate the muscle and ease the spasm. But, there’s now the belief that certain people with piriformis syndrome have an elongated or stretched piriformis muscle already and stretching could make it worse.
How do you know whether the piriformis is stretched or shortened? One way to differentiate between an elongated piriformis muscle and a shortened one is to look at the degree of hip rotation a person has. If the piriformis muscle is elongated, medial rotation of the hip on the affected side is greater than on the healthy side. If it’s shortened, hip rotation on the affected side is reduced. It’s a good idea to let a physical therapist or health care professional assess this.
If the piriformis muscle is shortened, deep tissue massage may help the symptoms, but if the piriformis muscle is stretched, deep tissue massage will have little benefit. Instead, the elongated piriformis muscle needs to be strengthened. Glute bridges and lateral band walks are two exercises that help strengthen the piriformis muscles. Physical therapy can be helpful in cases where the symptoms persist. That’s why it’s a good idea to get a professional evaluation if you have this condition.
Can You Prevent Piriformis Syndrome?
Although there’s no surefire way to prevent inflammation of the piriformis muscle, avoiding repetitive activities, like long distance running, that irritate the piriformis can help. Running on flat ground and avoiding hills, due to the eccentric contractions when you run down, may help too. At the opposite extreme, avoid long periods of sitting. If you have frequent hip and buttocks problems, get your legs measured. If you have a significant discrepancy between the lengths of your two legs, you may benefit from an orthotic that lifts the heel one side and corrects the length discrepancy. It’s also a good idea to limit how often you wear high heels too!
The Bottom Line
If you have buttocks pain that gets worse when you sit, it may be piriformis syndrome. It’s also important to rule out a herniated disc since the symptoms can be similar with the two conditions. Be aware that leg length discrepancies, sitting too much, excessive running, foot problems, and wearing high heels place you at higher risk. Work on correcting these risk factors if you want to avoid this common cause of buttocks pain.
Eur Spine J. 2010 Dec; 19(12): 2095–2109.
Athletico Physical Therapy. “Strengthen and Stretch: It’s what the Glutes and Piriformis Need”
Squat University. “How to Correctly Treat Piriformis Syndrome”
UptoDate.com. “Approach to hip and groin pain in the athlete and active adult”
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