Piriformis syndrome is a peripheral neuritis of the sciatic nerve caused by an abnormal condition of the piriformis muscle. This syndrome often goes unnoticed as it tends to present similarly to other conditions such as lumbar radiculopathy, sacral dysfunction along with others.
Piriformis syndrome occurs when the piriformis muscle irritates the sciatic nerve, leading to sciatica. The Piriformis is a muscle found in the gluteal (buttock) area. It runs from the sacrum, over the sciatic nerve, to insert into the hip joint. Thus, any tightness or inflammation in the piriformis muscle may lead to increased pressure on the sciatic nerve below it. This causes symptoms representative of sciatica (buttock pain, leg/foot pain/numbness/pins and needles).
Piriformis syndrome occurs most frequently during the fourth and fifth decades of life and affects individuals of all occupations and activity levels. Piriformis syndrome is more common in women than men, possibly because of biomechanics associated with the wider quadriceps femoris muscle angle (Q angle – refer to previous blog on ‘The Female Athlete’ for details) in the pelvis of women. However, difficulties arise in accurately determining the true prevalence of piriformis syndrome because it is frequently confused with other conditions.
There are two types of piriformis syndrome :
- Primary Piriformis Syndrome;
- Secondary Piriformis Syndrome.
Primary piriformis syndrome has an anatomic cause, such as a split piriformis muscle, split sciatic nerve or an anomalous sciatic nerve path. Secondary piriformis syndrome occurs as a result of a precipitating cause, including macro-trauma, micro-trauma, ischemic mass effect and local ischemia.
Among patients with piriformis syndrome, fewer than 15% of cases have primary causes. Piriformis syndrome is most often caused by macro-trauma to the buttocks, leading to inflammation of soft tissue, muscle spasm, or both, with resulting nerve compression. Micro-trauma may result from overuse of the piriformis muscle, such as in long-distance walking or running or by direct compression. An example of this kind of direct compression is ‘wallet neuritis’ (ie. repetitive trauma from sitting on hard surfaces).
- Pain with sitting, standing, or lying longer than 15 to 20 minutes
- Pain and/or paresthesia radiating from sacrum through gluteal area and down posterior aspect of thigh, usually stopping above knee
- Pain improves with ambulation and worsens with no movement
- Pain when rising from seated or squatting position
- Change of position does not relieve pain completely
- Difficulty walking
- Numbness in foot
- Pins and needles down the back of the leg and/or in the foot
- Weakness in ipsilateral lower extremity
Throughout the physical evaluation of patients, clinicians should maintain a high index of suspicion for piriformis syndrome. Early conservative treatment is the most effective treatment.
Stretching of the piriformis muscle and strengthening of the abductor and adductor muscles should also be included in patient treatment plans. Manual therapy by the physiotherapist may include soft tissue/massage therapy, stretching and acupuncture.
If you are experiencing any of the symptoms listed feel free to contact us at Function360 for advice.