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Introduction Slipped disc is the common name for the medical term prolapsed or herniated disc. Many people in the UK have back pain and although a slipped disc causes back pain, there are many other causes and a slipped disc is not a very common cause. The discs are protective, circular pads of cartilage that lie between the bones of your spine (vertebrae) and cushion the vertebrae when you jump or run. They are made up of a tough, fibrous case, which contains a softer gel. The spinal cord is a collection of nerve fibres that come from the brain and are protected by the spine. Nerve fibres from the spinal cord come out from between the vertebrae and take and receive messages to different parts of the body. A slipped disc occurs when the outer part of a disc ruptures and allows the gel inside to bulge outwards from between the vertebrae. The damaged disc can put pressure on your whole spinal cord or on a single nerve fibre. This means that a slipped disc can cause pain both around the area of the bulge or anywhere along the area controlled by an affected nerve. A slipped disc occurs most frequently in your lower back, but any disc can rupture, including those in your upper back and neck.
Symptoms Slipped discs occur most often in your lower back. The main symptoms of a slipped disc in this region are sudden, severe back pain, muscle spasm and sciatica. Sciatica is pain, numbness, weakness, or tingling that extends down the sciatic nerve that runs from your lower spine through each buttock and leg. Usually the pain is only on one side. The pain is often made worse by moving, coughing or straining. If a slipped disc occurs higher up the spine the symptoms can include a band of pain or numbness around your chest, as well as back pain. If a slipped disc occurs at neck level the symptoms are pain in your shoulder, neck, arm, or hand, muscle spasm and stiffness of your neck. If the gel inside the disc escapes directly backwards it may press very firmly on your spinal cord. This can cause sciatica in both legs, numbness in the saddle area between your thighs and difficulty in controlling your bladder or bowels. This is known as Spinal cord compression. It is a medical emergency and needs urgent treatment to prevent permanent damage to the spinal cord.
Causes A slipped disc usually happens when your back is bent forward and a large amount of pressure is put on a disc. Bending forwards opens up the gap in the vertebrae at the back of your spine and makes it easier for the disc to slip if it is squeezed. For example, by the strain that is put on your back when you are attempting to lift a weight. The way you stand, sit or move can also be a factor in whether you damage a disc. It is not clear why some people develop a slipped disc and others dont. However, there are factors that make a slipped disc more likely. You are more likely to suffer a slipped disc if you: have a job that involves heavy manual labour, are lifting incorrectly, especially while twisting or turning, have a job where you sit for a long time, have a job where you drive for many hours at a time are overweight, are a smoker, have had a slipped disc before, have spine problems in your family, are male, or are older or elderly, as your discs weaken with age.
Diagnosis Your GP will normally be able to diagnose a slipped disc from your description of any pain you are experiencing, along with a physical examination of your back, legs and feet to identify any sciatic nerve problems. If your back pain does not go away within 4-6 weeks your GP may suggest that you have an MRI or CT (computed tomography) scan of your spine. This will confirm whether or not your back pain is from a slipped disc and rule out more serious but rare causes, such as cancer. The scan will allow your doctor to see the size and site of the damaged disc better, which is useful in deciding whether you need surgery for your slipped disc.
Treatment In 90% of cases the pain from a slipped disc gets better on its own and does not require surgery. However, the process may take some time. For most people the condition gets a lot better within about six weeks. The first step to treating a slipped disc is to make sure that you do not make it any worse. You should avoid any form of lifting for three months to allow the disc to heal and you should take care not to strain or bend. You should stay active instead of lying in bed, as most doctors no longer recommend bed rest for back pain. However, you may need to rest on whatever surface is most comfortable until the initial intense pain of the injury has subsided. Your GP may prescribe a painkiller or recommend one you can buy from the chemist, such as paracetamol or ibuprofen. Ibuprofen is not recommended if you have a history of asthma, kidney, or liver disease.
Physiotherapy, exercise and massage can all be considered. Studies so far on the subject have not been very conclusive but it is thought that spinal manipulation from a chiropractor, physiotherapist, or an osteopath may help take the pressure off the nerves that are being pressed by the damaged disc. If healing does not happen on its own within a reasonable time, usually not less than six weeks, surgery may be considered. The aim of surgery is to remove the portion of the disc that is bulging out and causing the pressure on the nerves in your back. The procedure gives fast relief for most people who have lower back pain and sciatica caused by a slipped disc, but about half of those who have surgery will need a repeat operation at some time in the future.
Prevention A few sensible precautions and a healthy lifestyle can help prevent back pain or a slipped disc and decrease the chances of the recurrence of a previous injury: Regular exercise can decrease the hardening and natural breakdown of the discs in your back that comes with the aging process. It can also help keep the supporting back muscles strong and supple. Both should help prevent injury. Use the correct techniques for lifting. Lifting should be done with your back straight and your legs bent and taking the weight. Heavy lifting while bending or twisting should be avoided. Make sure you warm-up and cool down with stretching exercises before any workout or sports activity. Make sure you have a comfortable, supportive seat when sitting or driving for a long period and take breaks to stretch and walk around if possible. If you are overweight there is extra stress on your back.
Losing weight will help. Try to keep a good posture. Try to walk or stand with your head and shoulders slightly back. When sitting at a desk, make sure that your chair is the right height for the desk. Your feet should be able to rest flat on the floor with your knees bent at 90. You should sleep on a bed with a mattress that matches and supports your spines natural curves.
Glossary Brain The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.
Liver The liver is the largest organ in the body. Its main jobs are to secrete bile (to help digestion), detoxify the blood and change food into energy.
Bladder The bladder is a small organ near the pelvis that holds urine until it is ready to be passed from the body.
Kidney Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body.
Spine The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.
MRI MRI stands for magnetic resonance imaging. It is the use of magnets and radio waves to take detailed pictures of inside the body.
Physiotherapy Physiotherapy is a treatment that uses physical movements, massage and exercise to relieve illness or injury.
Numbness Numbness refers to a lack of sensation in a part of the body. Pain Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.
Rupture A rupture is a break or tear in an organ or tissue.
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