This leaflet is intended to reinforce the things that have already been discussed about your back and your forthcoming operation.
Anatomy
The spinal column consists of 24 bones called vertebrae. They are connected together by small joints (called facet joints) and a spongy intervertebral disc, which together allow a small amount of movement between each vertebra and a large amount of flexibility over the spine as a whole (Fig. 1).
Each disc consists of a soft spongy central portion (the nucleus pulposus) and a tougher fibrous outer coat (the annulus fibrosus). Directly behind the disc are the spinal nerves (Fig 2).
As we get older the disc dries out and becomes less spongy, and small tears start to occur in the fibrous coat. As the fibrous coat is thinnest at the back (by the nerves) this is unfortunately where
problems usually develop. Eventually the fibrous coat becomes torn to such an extent that the spongy nucleus may cause it to bulge out and press on a nerve, or else a piece of the nucleus may squirt out (like toothpaste from a tube) and press directly on the nerve (Fig. 3).
This is a prolapsed intervertebral disc (slipped disc), which may cause severe pain, as well as weakness and sensory changes in the area that the compressed nerve supplies. For discs in the lower back (lumbar discs) this is usually down the leg and into the foot.
Can it get better on it's own?
If the disc bulge isn't too large and there is sufficient room within the spine then the symptoms may go away after 6-8 weeks of rest. This is what happens in the majority of cases and these people may never have another episode. If however, the disc fragment is very large, and the symptoms do not settle after several weeks of bed rest and pain relief then surgical removal is the next option.
Microdiscectomy This is one of the commonest neurosurgical operations. Under a general anaesthetic (so you are asleep) an incision about an inch long is made in the back between the appropriate vertebrae (Fig. 4).
Then, using the operating microscope, a small hole is made in the ligament between the vertebrae to expose the nerve and the disc. The nerve is gently held out of the way while the disc is carefully removed (Fig 5).
The wound is then closed with an invisible dissolvable suture, so there are no stitches to be removed later on.
The Hospital Stay
Usually you will be admitted to hospital the day before the operation. After surgery you will be encouraged to get out of bed and walk around as soon as possible. Most people are well enough to go home the evening or next day after surgery.
Post Operative Course
When you go home you will need to take it very easy for the first few weeks. The wound should be kept dry for the first week so you will have to shower around it to start with. Initially, you will find lying or standing much more comfortable than sitting, but you will gradually find that you are able to sit comfortably for longer periods of time. You are to be encouraged to go for a walk once or twice a day and to gradually increase the distance you go. Regular swimming is also very good exercise. It is difficult to give a comprehensive list of "dont's" as everyone's circumstances differ; but lifting, twisting or excessive bending and stretching should all be avoided during the first few weeks. Driving (or travelling as a passenger in a car) is often quite uncomfortable for a while after microdiscectomy. Apart from your journey home it is therefore best to avoid this for a few weeks if you can, and then gradually build it up again, starting with short journeys.
The symptoms may well not settle immediately, particularly if the disc prolapse was large and had been pressing on the nerve for a long time. Leg pain is usually the first to settle, followed by any weakness. You may well experience tingling, pins and needles or other odd sensations for some months however as these symptoms are usually the last to improve, and may not resolve completely.
Getting back to work and the longer term
The main aim of microdiscectomy is to relieve the pressure on the nerve so it has a chance to recover, thereby allowing your symptoms to improve. The intention is always to try and get you back to the same job, sports and social activities, essentially the same life-style, that you had before.
A prolapsed disc however should be taken as a warning that your back is a bit worn in places and therefore deserves a little more care in the future if the risk of further problems is to be minimised. This may necessitate some sensible adjustments to your life-style such as.
• Making sure you are not over your ideal weight. Every extra pound is extra strain on your back.
• Avoiding heavy lifting and ensuring that any lifting you do is done with a straight back (Fig 6), with the load as close to you as possible.
• Making sure that the lower part of your back is properly supported by whatever chairs you usually sit in: especially if you work for long hours in a seated position.
• Taking a little regular exercise to maintain muscle strength and general fitness. It will also prevent your weight from creeping up!
Follow up
You will be reviewed regularly after your discharge, initially every few weeks, and then at longer intervals until you are completely better.
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