Related articles: Piriformis syndrome
Definition
Piriformis syndrome is a disorder that occurs when the piriformis muscle, located in the gluteal region, compresses or irritates the sciatic nerve. This phenomenon produces symptoms similar to other conditions that evolve into sciatica.
The piriformis is a small muscle located deep in the buttock (behind the large buttock), which extends from the pelvic surface of the sacrum to the upper edge of the great trochanter of the femur; plays an important role in the rotation of the hip and in the movements that allow to turn the lower limb outwards. In the presence of any problems, this muscle can compress the sciatic nerve at the point where it emerges from under the piriformis, before passing over the lateral rotators of the hip.
Piriformis syndrome can be caused by various causes, which include anatomical changes in the muscle-nerve relationship (eg muscle hypertrophy, fibrosis and postural disorders), excessive strain or injury to the buttock, hip or lower back, such as a car accident or a fall.
Most common symptoms and signs *
Further indications
Piriformis syndrome causes pain, often described as a tingling or radiated numbness along the course of the sciatic nerve (it starts at the level of the buttock and extends to the entire back of the thigh and leg, sometimes up to the foot). In some cases, the pain in the buttock is chronic, fixed and pungent, and may be associated with limitation in joint movements of the hip.
Painful symptoms can worsen during the course of daily activities involving the piriformis muscle (for example, when you go up and down the stairs or while driving the car) or after sitting for long periods of time; the pain can improve instead with the rest in supine position.
Piriformis syndrome is mainly defined on the basis of the symptoms that the patient manifests and on the physical examination, after the exclusion of other possible causes. The syndrome is often confused with a problem affecting a lumbar vertebral disc, as the symptoms are similar to a compression or an irritation of the spinal nerve roots. However, compared to piriformis syndrome, sciatica from discopathy is usually associated with low back pain.
When the differentiation between the two conditions is difficult, it may make it necessary to resort to instrumental diagnostic tests (such as X-rays, CT and MRI).
Therapy is symptomatic. In general, the approach to the disorder begins with specific physical exercises and stretching for the posterior hip and the piriformis, which allow the movement to be rehabilitated. Most treatments are aimed at reducing the pressure exerted by the piriformis muscle on the sciatic nerve. To relieve local pain and inflammation, analgesic and muscle relaxant drugs can be prescribed. In severe cases, local corticosteroid infiltrations may be indicated. Surgery is rarely necessary.
