What is sciatica?
The sciatic nerve is the largest nerve in the body. Nerve roots that originate from the spinal cord pass out between the disc spaces and join to form the sciatic nerve. The nerve then travels through the buttock and down the back of the leg.
The term ‘sciatica’ is widely used but often misunderstood. Sciatica is not a diagnosis in itself, rather the term is used to describe a set of symptoms caused by compression or irritation of the sciatic nerve or its nerve roots. Symptoms of sciatica may include pain down the leg, numbness, pins and needles or weakness. Symptoms are usually down one leg but both may be affected. Typically, sciatica is made worse by bending, lifting, sneezing or coughing.
Causes of Sciatica
- Herniated disc – The intervertebral discs are located between the vertebrae of the spine. They consist of a hard outer layer and a soft gelatinous centre. If the outer layer becomes weak, through age or injury, the centre can bulge out and compress the nerve roots causing pain and inflammation
- Osteophytes – Bony spurs or growths at the edge of joints that can apply pressure to nerves
Spondylolisthesis – Where one vertebra slips forward on top of the one below (usually L4 and L5), causing compression of the spinal canal and pressure on the nerves
- Pregnancy – Pain may result from the growing uterus causing pressure on the nerves or due to the postural changes associated with pregnancy
- Pseudo Sciatica – This is referred pain from the joints and soft tissue of the back which may be felt in the low back and back of the leg but is not caused by compression of the nerve roots
- Piriformis syndrome – where tightness of the piriformis muscle in the buttock compresses on the sciatic nerve
How can physiotherapy help?
Physiotherapy for sciatica is aimed at removing the pressure on the sciatic nerve, reducing pain in your back and leg and restoring function. A physiotherapist will begin by taking a detailed history from you to work out the cause of your pain. They will then perform a physical assessment, including spinal, orthopaedic and neurological examinations, to determine the exact cause of your sciatic nerve interference.
Treatment for sciatica may include soft tissue massage, spinal mobilisation, ultrasound, TENS and traction. An appropriate program of exercises will also be prescribed to improve core stability, strength, range of movement and muscle flexibility. Where appropriate, hydrotherapy may be used as an adjunct to treatment.