Many patients seek physiotherapy with complaints of sharp, shooting pains down the back of the leg usually starting from the buttock or lower back. Patients complain of difficulty walking, sitting, sleeping, and they just can’t get comfortable. Moreover they may experience burning and tingling or numbness in the leg.
A thorough examination with specific positive findings often reveals the problem to be sciatica.
Sciatica refers to an inflammation of the sciatic nerve. The sciatic nerve is comprised of 5 nerve roots: the fourth and fifth lumbar nerve roots and the first to third sacral nerve roots. These nerve roots join together on each side of the lower back and form the large sciatic nerve which runs through the buttock under the piriformis muscle and under the hamstring muscles in the back of the thigh. The sciatic nerve starts to branch off into smaller peripheral nerves in the back of the thigh. These nerves supply different muscle groups and sensation to the leg.
The sciatic nerve becomes inflamed and irritated when it is compressed. The cause of nerve compression could be due to a disc herniation in the lower back at the fourth and fifth levels or narrowing of the foramen where the nerve exists due to degenerative changes. Nerve compression causes pain, and possibly reduced conductivity. This would result in altered sensation and weakness in the muscles that the nerve root supplies.
A detailed examination will test the lower quadrant (low back & legs). Specific findings would reveal sciatica: a limited passive straight leg raise is usually a positive sign as well as reduced lumbar spine mobility. Muscle testing will reveal any leg weakness ie. ability to walk on toes or heels.
Physiotherapy is usually helpful. Treatment aims to reduce the compression in the nerve root. Specific manual techniques are useful. Exercises to strengthen the lower back and abdominals muscles help reduce pressure in the disc. Modalities such as electrical current, ultrasound and ice can help reduce the inflammation and ease the pain. Medication is often prescribed by the physician to help relieve pain and inflammation.
Written by Susan Reive, Owner of Kilborn Physiotherapy Clinic