Sciatica
Sciatica can be described as pain in the back and legs, caused by pressure on the lumbar nerves exiting the lower spine. It affects up to 40% of the population, and typically occurs in people in their 30s and 40s and older, due to injury to the low back or arthritis in the spine.
Sciatica is the name for a presentation of symptoms, characterised by:
Leg pain, usually only one leg at a time
Numbness
Pin and needles
Tingling
Weakness in affected leg
Pain that starts at the back and travels down the leg, past the knee
Causes
Sciatica is a set of symptoms, as a result of other underlying issues. Most causes of sciatica originate from the low back, such as herniated or degenerated discs, spinal stenosis, or spondylolisthesis.
Muscle spasms can also cause sciatica by compressing the sciatic nerve as it travels through the muscles. Less common causes of sciatica include infection, pelvic injury or fracture, and tumours.
In older age groups, sciatica may occur as the result of conditions caused by spinal degeneration, such as spinal stenosis. This is where the pathways through which the sciatic nerve travels are narrowed, causing compression and/or irritation of the nerve. Age-related outgrowths of bone (bone spurs) on the vertebrae can also compress the sciatic nerve.
While any injury or process which causes compression of the sciatic nerve can cause sciatic pain, in many cases there may be no specific cause identified for the sciatic pain.
Things can increase the likelihood of sciatica occurring:
Older age
Pregnancy
Being overweight
Smoking
Jobs that involve twisting of the back or carrying heavy loads
Sitting for long periods.