What is Piriformis Syndrome?
Piriformis Syndrome Explained by Las Vegas, Summerlin, and Henderson Nevada’s Top Pain Doctors
Prevalence estimates suggest that between 40 and 70% of adults will experience some form of lower back pain during their lifetime. Of these, epidemiological studies suggest that between 5-36% have lower back pain that is attributable to piriformis syndrome. Piriformis syndrome is relatively uncommon, though many believe that current estimates are skewed, and that piriformis syndrome is actually more common than studies report, due to the fact that so many cases of piriformis syndrome are thought to go undiagnosed.
The piriformis is a very large muscle that runs deep within the buttocks and attaches both at the lower back and the top of the femur. This muscle serves to rotate the hip, as well as turn the leg and foot outward. Additionally, the piriformis aids in balance and stabilization while walking. Thus, pain associated with piriformis syndrome seems to be related to irritation of the piriformis muscle. This irritation leads to swelling of the tissue that causes a compression of the sciatic nerve resulting in pain.
The specific symptoms of piriformis syndrome are widely varied, though the most common complaint from patients with this condition is pain after sitting for long periods of time. Pain with this condition is generally experienced within the piriformis muscle, particularly where the muscle attaches to the base of the spine and the femur, and along the sciatic nerve. Some patients will experience the pain as a highly specific sharp stab, while others will describe the pain as dull and achy. While the specific symptom depends on the underlying cause, some common complaints associated with piriformis syndrome include:
- Numbness in feet
- Difficulty walking
- Weakness in lower extremities
- Muscle spasms
- Radiating pain
- Neck pain
- Abdominal, pelvic, or groin pain
- Painful bowel movements
- In women, painful intercourse
Causes of Piriformis Syndrome
The specific causes of piriformis syndrome are largely unknown. In fact, a history of injury or trauma occurring in conjunction with symptoms is only reported in about half of all presenting cases. Overload on the piriformis muscle can lead to inflammation and, thereby, put pressure on the sciatic nerve. Thus, individuals who frequently engage in activities that involve running, lunging, or jumping may be more at risk. Piriformis syndrome occurs more frequently in women than in men. Interestingly, several chemicals causing inflammation and irritation of the sciatic nerve have been identified, such as prostaglandin, histamine, bradykinin, and serotonin.
In order to achieve the most accurate diagnosis, you may undergo a physical examination, including an assessment of pain and degree of swelling. Your physician will likely have a number of questions regarding your history, the onset of the current episode of sciatic pain, and a detailed description of the symptoms. Additionally, your physician will manipulate several of your joints and assess for pain experienced in an effort to confirm the diagnosis. Given that sciatic nerve pain associated with piriformis syndrome can arise from these different sources, identifying the underlying cause typically becomes a process of elimination in conjunction with your doctor.
Treatment for Piriformis Syndrome
In terms of pharmacotherapy, there are a number of medications available. Specifically, non-steroidal anti-inflammatory drugs (NSAIDs), including ibuprofen and naproxen; oral analgesics, including acetaminophen; as well as anti-depressants are recommended and have received some support in terms of their effectiveness in relieving pain associated with piriformis syndrome. Additionally, gabapentin, a drug frequently used to treat neuropathic pain, has also received some support as providing relief from pain associated with piriformis syndrome.
For chronic piriformis pain, a non-surgical nerve block procedure is recommended to provide patients with significant, and often complete, relief from pain. Located within the buttocks, the sciatic nerve is a bundle of nerves whose job is to transfer pain information from the legs to the spinal cord and brain. Thus, the sciatic nerve block is a non-surgical procedure to anaesthetize the sciatic nerve bundle and thereby prevent the transmission of pain information. Additionally, there is some indication that patients can experience a significant reduction in pain with spinal cord stimulation. This procedure involves implanting a device near the spinal column that delivers electrical impulses to control the transmission of pain signals from the nerves within the spine. Trigger point injections have also received some support in relieving pain related to piriformis syndrome.
Biofeedback training has received support for helping individuals manage their symptoms of pain. This non-pharmacological technique assists patients with recognizing symptoms in order to help them learn skills to control them. During this training, individuals are taught relaxation and coping skills, thereby allowing the patient to gain some control over their symptoms of pain.
Piriformis syndrome is a relatively uncommon pain condition affecting the piriformis muscle and sciatic nerve within the lower back and buttocks. Many believe that prevalence rates of piriformis syndrome are much higher than those reported owing to misdiagnosis of lower back pain. There are a number of treatment options available for managing the pain associated with piriformis syndrome. Patients with piriformis syndrome are encouraged to speak with their physician about the possibility of using corticosteroid injections to help relieve their symptoms of pain.
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