Piriformis Muscle Syndrome Treatments & Causes of Pain
Low back pain radiating down the leg may be caused by Piriformis Muscle Syndrome. The piriformis muscle starts on the sacrum and extends to the femur; it is a large and powerful muscle that stabilizes the pelvis during walking, squatting, and rotating the leg. The sciatic nerve is the largest bundle of nerves in the body, and it leaves the pelvis through the greater sciatic foramen. The sciatic nerve travels underneath the piriformis muscle (in some cases through the muscle fibers), and contraction can compress the sciatic nerve. Any compression of the sciatic nerve in the gluteal area could produce pain, dull ache, numbness, tingling, burning, weakness, loss of sensation, or weakness down the buttocks and leg. The deep ache and burning in the buttocks does not feel like a bone pain, rather it feels deep in the gluteal muscles.
The piriformis muscle and its tendon can become injured for a variety of reasons, most commonly injuries have a history involving chronic and prolonged sitting and inactivity. Overtime, hip muscles lose their flexibility and become chronically shortened, which increases the chances of injury with a couple hours of walking, hiking, bending, or lifting. It is more likely to occur in older or less active individuals after they exert themselves differently, especially with home, yard, or cleaning projects. A person who has difficulty squatting because of hip strength and ends up "hinging at the low back" to pick something off the floor is much more likely to injure their low back or piriformis.
Sciatica is a term used to describe pain that radiates from the low back and down the leg. There are several injuries that can produce radiating leg pain, and not all of them compress nerves. Piriformis syndrome is one of the many causes of sciatica, and is very commonly misdiagnosed condition by your healthcare provider, who assumes the radiating sciatic pain is caused by a lumbar disc herniation or lumbar joint sprain. Activities, positions, aggravating, and relieving factors are distinctly different in piriformis syndrome compared to disc herniations or spinal stenosis. Your doctor will compare your description of positions that aggravate and relieve your symptoms with a clinical functional movement exam to differentiate between the types of injuries that produce sciatica.
The lumbar spine (low back) sits on top of the sacrum and transfers weight from the torso to the pelvis through the lumbar facet joints and L5 spinal disc. These joint articulations absorb an incredible amount of body weight and stress, yet provide significant flexion, extension, and rotational movements. The sacrum sits in between the ilium on its left and right. Together the sacrum and ilium create the sacroiliac, or SI joint. The SI joint provides a significant amount of flexion and extension, allowing you to walk, climb, and sit. On the lateral side (outside) of the ilium is the acetabulum, where the head of the femur meets the pelvis. This joints is surrounded by cartilage, ligaments, muscles, and tendons.
The hip regions contains many muscles that stabilize the pelvis and allow tremendous movement in the sacroiliac and hip. The major hip muscles on the backside include gluteus maximus, gluteus medius, gluteus minimus, piriformis, obturator internus, obturator internus, superior gemellus, and inferior gemellus muscles. They are responsible for extension, external rotation, hip abduction, and lateral movements. They help stabilize the pelvis and hip with muscles in the front, which include the adductors, pectineus, gracilis, quadriceps femoris, tensor fascia latae, psoas major, iliacus, and sartorius muscles. Together the hips, low back, and core muscles stabilize the spine, pelvis, and femur, allowing us to walk, squat, run, and jump.
Several levels of nerve roots (L4-S3) can come together to form the sciatic nerve. The sciatic nerve travels down the pelvis and leaves via the greater sciatic notch. It is deep in the glute muscles and runs right underneath the piriformis, which is where piriformis muscle spasms can compress the sciatic nerve. Like most entrapment syndromes, a little compression can create severe burning, tingling, weakness, sensory changes, or radiating pain symptoms.
Sacroiliac spine disease, bursitis, spinal degenerative joint disease, degenerative changes in the muscle or tendon, inflammation, or trauma all could predispose a person to developing entrapment syndromes and nerve compression. Acute low back pain combined with degenerative disc disease causes a person to compensate with their hip muscles during walking and standing movements. People usually favor one side and create hip tightness, further increasing the chances of developing the problem.
Hip stabilizers become injured because of injury, chronic overuse, or degenerative changes in the pelvis, hip or lumbar spine. Lower back injuries may cause changes in the lower spine, leading to the pelvis tipping forward or backward, which places more strain on the supporting soft tissues. Specifically, changing the lumbar, sacrum, and pelvis angles increases glute medius, piriformis, and hamstring contractions in the attempt to stabilize the pelvis during sitting, standing, and walking. Change in pelvis tip requires the gluteal and hip muscles to work harder day to day, and eventually the overuse in hip stabilizers leads to spasms and compression of the sciatic nerve.
We are seeing more patients present with the condition after recovering from a recent abdominal, pelvic, hip, knee, or ankle surgery. As a result of the surgical procedure, the patients were less active and lost some muscle strength and endurance. Many focused on strengthening the muscles around the surgery, but they did not properly strengthen the hip stabilizers. As they returned to previous exercise levels, the hip weakness eventually led to entrapment syndrome.
Older patients are especially at risk. Senior citizens recovering from surgery often had weakness before the surgery. With increased age, it is harder to strengthen the muscle and increase flexibility. Hip and pelvic stabilizers are often not properly addressed leading to weakness. Now the older patients begin to hinge at the back instead of squat, because they cannot properly stabilize the pelvis. Hip weakness also is found on longer walks, when their hips begin to "wobble" side to side, which indicates hip weakness and increases the likelihood of the problem developing in the future.
Radiating sciatic pain is the most common symptom, and it occurs anywhere from the low back to the foot. It is most commonly felt in the gluteal and hamstring. The pain can radiate below the knee to the calf and bottom of the foot; this pattern is the most severe and usually occurs with getting up from a seated position or climbing stairs. Most times the pain radiates from the gluteal or hip and down to the knee. Burning, tingling, and changes in sensation can occur anywhere along the sciatic nerve distribution. People often describe burning or loss of sensation along the leg and back of the calf; in addition, it often skips the ankle and is felt on the bottom of the foot and patients describe a burn on the ball of the foot.
The condition can produce hip and leg weakness, and people feel like their leg is "giving out." When the hip muscles contract during squatting, climbing stairs, standing, or stepping off a curb, the extra hip stabilizing contraction compresses the sciatic nerve and the body stops you from contracting the muscle. This is a protective mechanism, where the body stops you from contracting a muscle that is causing more pain and discomfort. People find that internal or external rotation of the foot while they climb stairs helps relieve the deep, dull ache and sharp radiating burning down their leg.
As mentioned before, hip muscle contraction increases the discomfort and radiating pain down the leg. As expected, activities that decrease spasms and compression produce relief. Lying and sitting in certain positions allow the piriformis to relax, which removes the compression that is causing the leg symptoms. Any extra compression in the gluteal region, such as deep massage therapy, trigger point therapy, or palpation can reproduce piriformis syndrome symptoms. A strong hip or piriformis stretch increases the pain, and slightly lessening the stretch allows the symptoms to disappear. This is one of the orthopedic tests that your physician can perform to evaluate the condition. Tenderness is often found with palpation of the gluteal region and may reproduce the radicular pain.
The causes of mechanical low back pain are very similar: poor posture, repetitive activities, over exertion, chronic back pain, abdominal muscle weakness, and poor decision making (i.e. hold my drink and watch this). Previous back surgeries, multiple levels of disc degeneration, multiple disc herniations, hip arthritis, lack of hip flexibility, and hamstring hypertonicity all increase the likelihood of developing lower back pain, hip pain, or sciatica.
As mentioned before, mechanical low back pain, soft tissue injuries, muscle trigger points, degenerative disc disease, sacroiliac joint sprains, ligament strains, disc herniations, and single nerve root entrapments from lumbar facet arthrosis can all cause radiating sciatic pain; but the location of pain patterns, physical and neurologic history, relieving body positions, and aggravating postures produce different pain and burning symptoms. Each of these conditions responds to a different treatment, which requires proper diagnosis from your physician, physical therapist, or chiropractor.
Initial therapy goals are to reduce the muscle spasms and entrapment on the sciatic nerve. Your doctor may prescribe medication for inflammation and pain. Cortisone or steroid injections are not usually the first therapy option for the condition. When piriformis syndrome occurs with other causes of lower back pain, steroid injections may be used for the other injuries to joints and soft tissues. Some individuals are unable to take certain drugs because of prior health conditions, and should confirm with a doctor prior to taking over-the-counter medications. Other options for pain management include injections to decrease muscle spasms and enhance conservative treatment. Most patients respond very well to over-the-counter medication and a primary care's prescriptions, and injections for pain managements are less frequent and for those in severe pain radiating below the knees and not responding to conservative therapies.
Stretching, massage therapy, heat, ice electrotherapy, and manual therapy, are other excellent physical therapy treatments to quickly reduce spasms in the hip and buttocks. Alternative medicine is also very beneficial and effective. Some patients respond very well to acupuncture to decrease pain and relieve the compression.
Cold laser therapy (Low-Level Laser) is often used on nerve entrapment injuries to enhance nerve regeneration and repair, but it is also effective at decreasing pain and inflammation associated with spasms, tendonitis, and bursitis in low back, sacroiliac, and hip condition, as well as in the acute phase. Most case studies and journal articles on low-level lasers focus on decreasing inflammation, but its greatest benefit may be its ability to accelerate cellular repair, regeneration, and enhance nerve entrapment syndrome treatments.
Stretching needs focus on all the gluteal muscles because when the piriformis muscle is involved, the hip muscles above and below are also affected. Light stretching may reproduce some sensation radiating down the leg, but it should not go past the knee. Changing the angle and direction of the stretch will alleviate radiating, burning, and aching symptoms; moreover, changing direction also enhances flexibility in the other hip and back muscles. Stretching can feel strong and comfortable. Patients should stretch both of their hips, and not just not the affected side.
Exercises will increase strength and stability in pelvic and core muscles to establish normal pelvis and lumbar movements. Many of the exercises are similar to back pain treatments, especially if the hip weakness was the result of lumbar and core muscle weakness. Hip extension and lateral exercises will involve body weight and rubber band exercises. Hip and gluteus maximus neuromuscular education and proprioceptive activities will help to engage low back, hip, and pelvis stabilizers. Therapeutic exercises can involve strengthening bands, weights, vibration plates, foam, BOSU balls, and therapy balls. Exercises will advance to to more difficult single leg squats on unstable surfaces.
Long term goals will achieve proper strength and endurance for your age, and reduce the likelihood of future injuries. More article information on clinical symptoms, treatment techniques, exercises for sports specific prevention activities for athletes, and simple strengthening exercises for older adults is found on our exercise and anatomy pages.