Definition
In Piriformis syndrome, irritation of the sciatic nerve causes pain radiating from the hip, which is similar to a herniated disc in the lumbar spine, but is spatially and causally independent of it. It takes its name from the piriformis muscle (pear-shaped muscle), which exerts or transmits internal or external pressure on the sciatic nerve, thus causing irritation of the nerve.
Epidemiology
There are different indications of the frequency of lumbar syndrome. In a general practice, about one in twelve patients complains of deep back pain radiating into the buttocks and legs. Besides, 25% of all sickness-related work stoppages are caused by such complaints. About 42% of all patients with the appearance of pain in the area of the lumbar spine up to the course of the sciatic nerve, which are proven to have no herniated disc as a cause, suffer from piriformis syndrome.
Causes
Piriformis syndrome can have many causes. Accidents or falls on the buttocks can trigger the pain syndrome by pressure on adjacent parts of the sciatic nerve, but also lower pressure over an appropriate period of time on a certain area of the buttocks, such as by sitting on a purse in the back pocket or one-sided pressure on the buttocks when sitting, are described as causes. Piriformis syndrome can be caused by prolonged, monotonous strain, such as during endurance running, frequent lifting from the straddled legs or by prolonged, forward bending work.
In addition, the holding muscles, including the piriformis muscle, shorten quite frequently in old age, which can exert increased pressure on the sciatic nerve. Anatomically, the piriformis muscle pulls from the lower, lateral inner surface of the sacrum over to the inner surface of the large rolling mound on the thigh bone and is responsible for internal rotation, lateral abduction and posterior extension of the thigh. Directly below it, also coming from the sacrum, the sciatic nerve in the deepest part of the buttock pulls to the back of the leg.
This anatomical neighborhood is in most cases one of the causes of the piriformis syndrome, as well as the fact that the stretchability of the sciatic nerve is low and it is therefore susceptible to force effects. In anatomical position variants, the sciatic nerve can even run directly through the piriformis muscle or over its upper edge, which favors the development of the pain syndrome. You can find more information on this topic under:
- Causes of Piriformis Syndrome
- Incarcerated sciatic nerve
Piriformis syndrome is a typical jogger’s disease.
In this type of sport, the Piriformis muscle is heavily involved in the movement pattern, which is why the muscle can be tensed more often. In addition, jogging exercises the muscle, which can cause it to press on the sciatic nerve and cause pain. Most often, Piriformis Syndrome occurs suddenly while jogging, after a small bump in the ground had to be overcome. The pelvis has to react to the unusual movement, which causes sudden tension of the piriformis muscle, among others.
