Pain in the buttock that radiates down the leg is commonly called sciatica. The most common cause for sciatica is irritation of the spinal nerves in or near the lumbar spine. Sometimes the nerve irritation is not in the spine, but further down the leg one possible cause of sciatica is piriformis syndrome.
Piriformis syndrome is a painful musculoskeletal condition resembling sciatica, secondary to sciatic nerve entrapment in piriformis muscle at the sciatic notch. It is frequently goes unrecognized or misdiagnosed in clinical settings as it mimic common clinical entity like lumbar disc prolapse .It is first described in 1928 by Yeoman while studying the cause of low back pain. Robinson in 1947 introduced the term “Piriformis Syndrome” and applied it to sciatica due to abnormal muscle which is usually traumatic in origin.
Incidence and prevalence of piriformis syndrome is not clear, but it is suggested that piriformis syndrome is responsible for 6 to 36% of low back pain and sciatica cases. True prevalence is difficult to accurately determine because the diagnosis is largely clinical and is one of the exclusion
What is Pirifomis Syndrome?
Piriformis Syndrome refers to irritation of the Sciatic nerve as it passes through the piriformis muscle located deep in the buttock. Inflammation of the sciatic nerve causes pain in the back of the hip that can often travel down in to the leg (Sciatica).
How does it occur?
The piriformis muscle is located deep in the buttock and pelvis and allows you to rotate your thigh outward, The sciatic nerve travels from your back into your leg by passing through the piriformis muscle is unusually tight or if it goes into spasm, the sciatic nerve can become inflamed or irritated.
What are the Symptoms?
- A dull ache /burning in the mid buttock
- pain down the back of the leg
- pain when walking upstairs or inclines
- increased pain after prolonged sitting
- there may be groin or pelvic pain
- women sometimes complaining of dyspareunia
- patient may present with cervical, thoracic and lumbar pain and head ache due to compensatory or facilitative mechanism
- symptoms may feel easier after lying down on your back or changing position
How is it diagnosed?
Diagnosis begins with a complete history and physical exam.
Radiographic studies have limited application to the diagnosis of piriformis syndrome. Although MRI and CT may reveal enlargement of the piriformis muscle, these imaging technologies are most useful in this setting when ruling out disc and vertebral pathologic condition. Diagnostic imaging of the lumbar spine is necessary to exclude disc herniation, arthritis, fractures and pathological masses.
Electro diagnostic testing (EMG) is beneficial in differentiating piriformis from other conditions.
How is it treated?
Treatment may include
- Taking prescribed Non-steroidal anti-inflammatory drugs and muscle relaxants and referral to physiotherapy.
- If the patient does not respond adequately to the above treatment then injection with lidocaine hydrochloride, steroids or botulinum toxin type A(PTX-A) may be considered
- If all of the above treatments fail, the final treatment option is surgical decompression.
The most commonly reported physical therapy interventions include
- Heat or Cold therapy
- Ultrasound therapy
- Laser therapy
- Soft Tissue mobilization
- Dry needling
- Manual Therapy (Manipulation Mobilization of your Hip and Surrounding soft tissue)
- The keystone treatment for Piriformis is stretching exercises which focuses on relaxing tight muscles to relieve nerve compression
Piriformis Stretching Exercise’s
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