A B C D E F G H I J K L M N O P R S T U V W

SLIPPED DISC - DISC PROLAPSE

What is a Slipped Disc ?

The discs lie between the end surfaces of the bony blocks (vertebrae) that make up the spine. They have a soft centre which is surrounded by a tough outer ring. The discs allow movement of the spine and also act as shock absorbers. The nerves which run from the brain to the arms and the legs lie within the spinal canal. As the nerves leave the spine to go to the muscles and skin, they pass very close to the back of the discs. When a disc is damaged, the soft centre may slip out (prolapse) and press on a nerve. The usual place for such a prolapse to occur is in the lower back (lumbar) region. Less often the problem occurs in the neck (cervical) region. Damage to a disc may cause only back or neck pain at first. Once a prolapse occurs resulting in pressure on a nerve, pain is felt shooting down the arm or the leg (sciatica). Pins and needles are often felt in the foot, toes or in the hands. The area of skin supplied by the nerve may feel numb. Weakness of the muscles served by the nerve also occurs. The muscles of the back or neck will be very tense, and this will limit movement. Very ocasionally, all large prolapse will press on nerves to the bladder. The patient will then be unable to pass water. There is often sciatica in both legs at the same time. The majority of patients affected by disc prolapse are under age 40.

How does a Slipped Disc occur ?

A sudden increase in pressure on the disc causes a tear in the tough outer ring. If the tear extends right through the outer ring, some of the soft centre may prolapse. As well as local pressure on the nerve from the disc, there is swelling and inflammation. This inflammation is responsible in part for the severe pain caused by a disc prolapse.

Why does a Slipped Disc occur ?

Any situation which increases the pressure within a disc can lead to damage and prolapse. Lifting heavy objects with the back bent is a common cause. Coughing or sneezing may also cause a prolapse to occur. Less commonly, a fall or injury damages the disc.

Treatment involved for a Slipped Disc

In the majority of cases, surgery is not required. You will be advised to rest at home, lying flat, only getting up to go to the toilet. Anti-inflammatory drugs, muscle relaxants and painkillers will be prescribed for you. If the pain does not get better, then strict rest in hospital may be needed for a further 2 weeks. Traction may be used. This involves lying flat in bed, while weights pulling on ropes attached to the legs produce a slight stretching of the spine. This takes the pressure off the damaged disc. Ninety per cent of patients get better with this conservative type of treatment. Surgery is carried out to relieve persisting pain in the arms or legs. It is not generally used for back or buttock pain, or local discomfort in the neck. When the patient is unable to pass urine, or if muscle weakness is increasing rapidly, then immediate surgery is necessary. Before any surgery, it is important to confirm the site of the disc prolapse. This is done with a CT (computerized tomography) x-ray scan or magnetic resonance (MRI) scan. No spinal injections are needed with these methods and there is no pain or discomfort. Myelography may be used in some cases. This involves the injection of a dye into the spinal canal to outline the nerves on x-rays. Surgery is carried out under a general anaesthetic. For operation on a lumbar disc, the incision is in the middle of the lower back. The soft tissues between the vertebrae of the back are removed over a small area. Sometimes part of the bone of the vertebrae needs to be taken away also. This allows the nerve and the disc prolapse to be seen. The loose pieces of disc are then removed from in front of the nerve. Any other loose pieces lying inside the disc itself are also removed. The common name for this operation is laminectomy. Some surgeon use a form of keyhole surgery called microdiscectomy. When a disc in the neck is to be removed, the incision is made to one side across the front of the neck. Normally the majority of the disc is taken away to relieve the pressure on the nerve. Following this a piece of bone is used to bridge the gap between the vertebrae. The piece of bone is taken from the hip.

After treatment

After surgery, you will wake up with a plastic drip tube in one arm to give fluids. Blood is not usually needed. Injections and then tablets are given regularly for pain. Sometimes you may find it difficult to pass urine after surgery. A tube then needs to be put into the bladder. A physiotherapist will start muscle exercises on the day after surgery. You will probably be able to get out of bed between 24 and 48 hours after operation. After surgery on the back, no support is necessary. If a disc has been removed from the neck then a supportive collar is worn. Pneumonia, heart problems or a clot going to the lungs (pulmonary embolism) are rare. Sometimes there may be more numbness or weakness following surgery. This usually gets better with time. Severe damage to the spinal nerves is very unusual. In some people the pain in the arm or leg does not go away completely. This may be due to damage to the nerve itself by pressure from the disc before operation. Occasionally a blood clot collects under the skin at the operation site. Return home is between 5 and 7 days in general. It may be sooner after keyhole surgery. After discharge from hospital, normal daily activities can be gradually restarted. Bending and lifting should be strictly avoided for 3 months. Clerical work can be started once sitting is comfortable. This is usually about 6 weeks. More manual work should not be done for 3 months. Driving can start at about 4 weeks. The doctor should be contacted if there is any leaking from the wound, chest pain or increasing pain in the arm or leg. Another disc prolapse occurs in about 10% of people. This risk is greater in men involved in heavy manual work.

If a Slipped Disc is left Untreated

In the majority of cases, the pain will improve gradually. This may take many months or even a year or more. If there is pressure on the nerves to the bladder or spinal cord, then surgery is essential. Permanent paralysis and problems with passing urine will otherwise occur.

Effects on the family of a Slipped Disc

You will certainly need the support of someone to help you with day-to-day activities for the first couple of weeks at home. If not available, a period of convalescence with a friend or relative would be worthwhile.