This condition typically occurs in people aged 30-50, either spontaneously or with an episode of twisting, bending or lifting. The disc herniation can press on adjacent nerve roots leading to leg pain ‘sciatica’ with pins and needles, numbness and sometimes leg weakness.
What are the symptoms?
Gradual or sudden onset of leg pain, radiating down the front or back of the leg, with pins and needles and numbness. This is often proceeded by a period of back pain caused by the disc ‘tearing’. Sciatic symptoms may be aggravated by coughing, sneezing and straining. Occasionally the nerve may stop working leading to leg or ankle weakness called a ‘foot drop’.
Rarely a large disc herniation can press on the nerve roots supplying the bladder, bowels and sexual organs leading to incontinence and erectile dysfunction. So called acute cauda equina syndrome is an emergency, requiring immediate referral and surgery.
What is the prognosis and treatment options?
Leg pain can be very severe. Initial treatment is a combination of regular strong analgesia, including an anti-inflammatory, trying to keep moving with gentle stretching exercises, and lifestyle modification, avoiding prolonged sitting. Forceful manipulation of the spine should be avoided as this has the potential to aggravate or cause nerve damage.
In approximately 90% of individuals the pain will settle over 3 months as the disc resorbs or ‘shrivels up’, with significant improvements often occurring in the first few weeks.
Referral to the specialist clinic can be made at any stage, with the diagnosis made by history, examination, and usually MRI.
A targeted nerve root block is simple to perform and often highly effective particularly when performed acutely. Once the diagnosis is made, this can be offered by the clinic within a few days of symptoms starting.
If symptoms remain intrusive beyond 6 weeks then a lumbar microdiscectomy may be a good option. Significant motor weakness such as a ‘foot drop’ may be an indication for sooner surgery.