The piriformis muscle is flat and pear shaped. It sits in the buttock, between the sacral vertebrae to the greater trochanter of the hip bone. Depending on whether the hip is flexed or extended, this muscle is pivotal in helping the joint to externally rotate or adduct. It is innervated by nerves from the L4 thru S3 spinal cord levels. They come together as the largest single nerve in the body – the sciatic nerve- just above the piriformis muscle. It then runs through the middle of the piriformis muscle, and down the back of the leg to the foot, dividing into two branches behind the knee, providing both sensory and motor functions to the extremity. When stressed, inflamed, overused, or traumatized it can cause sciatic nerve symptoms resulting in hip, posterior thigh, calf and foot pain.
It’s estimated to be the cause of close to two and a half million new complaints of low back and leg pain annually. It usually occurs in middle age and seen six times more often in women than men.
Complaints often include:
- Hip and buttock pain.
- Pain with sitting long periods of time.
- Worsening pain with hip motion.
- Pain when getting up in the morning
- Tenderness when the muscle is palpated
- Shooting pain or burning ache from the buttock down the back of a leg.
- Numbness in the buttock and tingling along the sciatic nerve distribution.
- Discomfort while walking or running
It’s often caused by:
- Trauma to the buttock or hip areas.
- Sitting for prolonged periods of time e.g. truck drivers, jobs where sitting at a desk long hours is required.
- Weight lifting that causes the muscle to hypertrophy.
- Not properly warming up before and after exercising.
- Over exercising
- Stressing the muscle with a lot of running, hiking, stair climbing… that haven’t been strengthened or warmed up.
- Anatomical anomalies
- A bipartite muscle
20% of the population have a sciatic nerve that divides too early, predisposing individuals to piriformis muscle issues
There are no real tests to rule out this diagnosis. It is diagnosed once all other possibilities e.g. a herniated lumbar disc, spinal stenosis, sprain/ strain of other muscles or ligaments are ruled out and the signs and symptoms match a piriformis etiolgy.
Treatments may include:
- Physical therapy
- Muscle relaxants
- NSAIDs (non steroidal anti- inflammatory drugs) like Aleve and Motrin if appropriate to your medical history.
- Steroid injections
- Botox injections
- Alternating hot and cold packs
- Stretch and mobilize daily
- Lift properly- bend knees and squat. Keep items close to body and don’t twist while lifting.
- Maintain good posture when sitting, standing, driving.
- Warm up before and after exercising.
- Take frequent breaks to stretch, walk, stand … when sitting for long periods of time.
How to stretch and strengthen safely the piriformis muscle:
- Lie on your back. Pull one knee to your chest and hold for 30 seconds. Switch sides.
- Stand, then bend at your hips dangling hands and head to the floor. This will stretch the back of the buttock and legs.
- Lie on the forearms with straight legs and lift the hips off the floor into a straight line. Hold for 15 seconds. Also a type of plank exercise.
- Lie on your back with your legs straight. Lift affected leg and bend knee. With opposite hand reach across your body and gently pull your knee toward your opposite shoulder. Hold for 30 seconds.
- Lie on your back with both knees bent, feet flat on the floor. Put ankle of affected leg on opposite thigh, near knee. Use hand to gently push knee away from your body until you feel a gentle stretch in the buttock and hip. Hold for 30 seconds.
- Sit in a chair with both feet on the floor. Cross your ankle over the opposite knee. Let the knee fall towards the ground, keeping the ankle in place. Push your knee gently or lean forward to feel a stronger stretch in the buttock area.
- Lie flat on your back with both knees bent. Contract your abdomen and lift your hips off the floor as high as you can, then squeeze your buttocks and hold for 19 seconds. Slowly lower your hips back to the floor, and repeat,
Most episodes of piriformis muscle pain resolve in a few days or weeks with minimal intervention. If it persists talk to your healthcare provider.