|Classification according to ICD-10|
|ICD-10 online (WHO version 2019)|
As sciatica (from ancient Greek ἰσχίον is'chíon , hip 'and ἄλγος algos , pain), also briefly sciatica are pain and discomfort referred to the main nerve of the leg, the sciatic nerve ( the sciatic nerve , even sciatica called), are assigned and caused by irritation or damage to its nerve fibers . If, in addition to neuralgia (nerve pain), other neuropathic impairments occur in the supply area of this nerve , for example muscle weakness or sensitivity disorders , it is also referred to as sciatica ; older names that are not commonly used are Cotugno syndrome and (nervous) hip pain .
In most cases the complaints are caused by pressure on the nerve roots of the spinal nerves emerging from the spinal column and originating from the spinal cord , i.e. a radiculopathy . In the supply area, the area is often only affected by a single spinal nerve on this side. Often this is one of the lower lumbar spinal nerves, belonging to the fifth segment of the lumbar cord in humans (L 5 ), or an upper sacral one , belonging to the cruciate cord (S 1 ).
Typical of the so-called sciatica is an increase of intensity or spread of pain in the leg at an elongation of the nerve, such as diffraction straight leg in the hip . On the other hand, the common lumbago , medically called lumbago , in the lumbar spine area is associated with back pain that does not radiate into the legs. A combination of lumbago and sciatica is called lumbar sciatica .
The cause of the radiculopathy of lumbar (L 4,5 ) or sacral (S 1,2,3 ) spinal nerve roots, often referred to as sciatica , is predominantly degenerative changes in the intervertebral discs or spine , which generally increase with age. They are caused by the static load in the more or less upright bipedal posture typical for humans and are accelerated by inappropriate loads and excess weight.
This in every human age-related increasing changes can have the consequence that nerve fibers in the narrow openings of intervertebral foramen ( intervertebral foramen ) when passing into the spinal canal are compressed. Such a compression of the nerve root can occur, for example, when intervertebral disc tissue protrudes above a certain level, for example in the case of a herniated disc or disc protrusion as a result of progressive attrition (degeneration) of the disc. Bony changes in the vertebral bodies , for example spondylophytes as a result of signs of wear ( osteochondrosis ) of the axial skeleton or vertebral fractures ( e.g. as a result of osteoporosis ), can irritate the nerve roots and thus lead to sciatica.
A sciatica but may also occur if the actual sciatic nerve becomes irritated, or on the course of its path (for example by pressure or inflammation) damaged. The sciatic nerve emerges from the sacral part of the lumbosacral plexus (lumbar cross plexus) with parts of the spinal nerves L 4 to S 3 . It leaves the pelvis at the level of the buttocks , runs to the back of the thigh , gives off various branches here, and finally branches to the tips of the toes . The sciatic nerve is the thickest of the peripheral nerves in the human body and supplies several muscles of the thigh as well as the muscles and almost all of the skin of the lower leg and foot .
If the sciatic nerve is compressed between the pelvic bone and the piriformis muscle when it passes through the infrapiriform foramen , a piriformis syndrome can occur. There are also a number of other possible causes of sciatica, including extensive tumors or, for example, herpes zoster along the nerve tract .
- MA Stafford, P. Peng, DA Hill: Sciatica: a review of history, epidemiology, pathogenesis, and the role of epidural steroid injection in management. In: British Journal of Anesthesia (BJA) October 2007, Volume 99, No. 4, pp. 461-473: Review; doi: 10.1093 / bja / aem238 , PMID 17704089 .