What is the function of the spinal column? Stability The function of the human spinal column is above all to stabilise the head, the upper body, and walking upright. Primarily responsible for this are the vertebrae. These are box-shaped bones, which by virtue of their construction are particularly resistant to downward forces such as occur in jumping, but also in climbing stairs or while walking. Mechanical protection The vertebrae and the vertebral arches form a canal in which the spinal cord and the nerve endings are contained and protected from external influences. Shock absorption and mobility "Shock absorbers", the intervertebral discs, lie between the vertebrae to cushion impact forces, and, together with the vertebral joints, to make it possible for the torso to turn, stretch and bend.
The slipped disc The intervertebral disc is flat, and consists of a fibrous outer ring (annulus fibrosus) and a gelatinous inner core (nucleus pulposus). Under stress, this structure works like a water cushion, distributing pressure evenly over the neighbouring vertebrae. If the fibrous ring and the gelatinous core become loose, which can happen for a wide variety of reasons, the high pressure on the disc and the weight of the body make the disc bulge forward towards the spinal canal and the nerve ending. If the fibrous outer ring tears, disc tissue can protrude into the spinal canal (slipped disc or prolapse). This leads to compression of the passing nerve endings, which results in: back pain pain spreading into the legs sensory disturbances (numbness) paralysis disturbance to urination, defecation and sexual function.
IIn the overwhelming majority of cases it is the 5th and 4th lumbar discs which are affected, and more rarely the 3rd and 2nd. The precise diagnosis will be made by the doctor from the patient's previous history, from the clinical examination and from imaging techniques. Computer tomography In most cases, a slipped disc can be diagnosed using computer tomography (CT), a form of x-ray examination which makes the individual structures of the spinal canal, i.e. the bones, the dural sheath, the nerves and the prolapse directly visible. Nuclear magnetic resonance imaging It is becoming more and more common to use nuclear magnetic resonance imaging (NMR, MRI), a relatively new examination which does not involve x-raying the patient, to diagnose a slipped disc. Medullography If the findings are still not clear, we carry out a medullographic examination. This is an examination using a contrast medium, and involves introducing a needle into the spinal canal and extracting nerve fluid for chemical examination in the laboratory to exclude the possibility of other illnesses. Then the contrast medium is injected. X-ray images now show the exact site of the prolapse. The contrast medium is expelled from the body through the kidneys within 6 to 8 hours. After undergoing medullography, the patient should lie down for 2-3 hours and subsequently drink a lot of fluid. Occasional complications are headaches and muscular spasms in the legs, and very rarely hypersensitive reactions to the contrast medium can occur.
Many cases of slipped disc can be treated conservatively (rest, pain relief, therapeutic exercises, physiotherapy). However, if pain or paralysis symptoms (slight paralysis in the legs, numbness) persist despite adequate treatment of this kind, surgery should be considered. If severe paralysis and/or bladder, rectum or sexual function disturbances occur, surgery must be performed immediately, since the danger otherwise exists that these functions, e.g. control of the bladder, will be lost permanently.
Slipped disc surgery The aim of the operation is to alleviate the pain and to cure any paralysis or sensory disturbance which existed before the operation. Since the introduction of microsurgery methods, the operation has become less traumatic, safer and more successful. An incision 3-4 cm long is made in the skin, the fascia of the back are cut into lengthways and the muscles in the back are detached using a non-sharp instrument. With special instrumentation the surgeon now makes a tubeshaped access to the spinal column and opens the spinal canal with the help of a surgical microscope. Under strong magnification the slipped disc can be clearly seen and removed. The remaining degenerated disc tissue is then removed from the intervertebral space, relieving the compressed nerve ending which can now recover. After bleeding has been carefully stopped, the various layers of the wound are closed and the operation is over. (Surgery normally lasts for 1-1 1/2 hours.) In 90-95% of cases the operation is performed without complications. However, the following complications can rise in a few cases: infection 2% secondary bleeding 1-2% increase in paralysis symptoms (mostly only temporary) 3-5% injury to the surface of the nerve 2% In extremely rare cases injury can occur to the abdominal organs in front of the intervertebral disc (e.g. abdominal vessels).
What happens after the operation? After your slipped disc surgery the stability of your spine is ensured in every case. It is therefore important to get you "on your feet" as quickly as possible, while at the same time not putting any strain on the wound. In principle, you can get out of bed for a short time on the day of the operation itself and go to the toilet accompanied, as long as your doctor does not give instructions to the contrary. The following day you will begin your physiotherapy exercise programme to strengthen your abdominal and back muscles, and you will be given instructions on movements which are good for the spine. You should carry on with these exercises long-term after you have left hospital and returned home. The rapid relief from pain which most patients experience after microsurgery brings some dangers with it. Many patients become careless and put their spine under strain too early. This can give rise to a very intensive, local pain, which only goes away again after a comparatively long resumed resting period - i.e. strict bed rest. We therefore ask our patients to follow the instructions given below and thereby contribute to their own rapid recovery. From the first day after the operation, you may sit up. However, longer periods of sitting may lead to unspecified aches and pains. For the first 6 weeks, you should avoid sitting on deep sofas and sitting for a long time in the car. You should also avoid carrying heavy objects during this period. Activities which lead to pain in the back or legs should be reduced. Your wound: your wound will only hurt for the first few days. The stitches are removed on the 7th or 8th day after the operation. If your wound is healing normally, you may have a shower from the 5th day, with a waterproof plaster protecting your wound. Many patients experience sciatic-type pain, similar to the pain they had before surgery, between the 4th and the 7th day after the operation, but this pain quickly disappears again, and you should not be worried by it. Paralysis: paralysis or sensory disturbances which existed before surgery do not disappear immediately after the operation. It can often take weeks or months for this to return to normal, depending on the extent of damage to the nerves.
Correct behaviour after discharge After you have been discharged from hospital (if no complications have arisen, between 3 and 7 days after the operation), the doctor who referred you to hospital or your GP should continue your treatment (physiotherapy, exercises, medication if necessary). The treatment you receive will be tailored to your needs. The therapeutic exercises you learnt in hospital should be performed for 5 to 10 minutes twice a day. You may now go for short walks, increasing the distance from day to day. The success of slipped disc surgery depends quite fundamentally on the patient's own sensible behaviour. For 4 to 6 weeks you should avoid any heavy physical straining or bending of the spine. Sleeping: there are no special restrictions concerning sleeping. You can sleep in whatever position and on whatever mattress is comfortable for you. Sport: in the first 4-6 weeks, you should avoid sporting activities (apart from walking). About 85-90% of patients return to full health and fitness after the operation. After this time, you may return to work and take part in most types of sport. The best activities for you are swimming, gymnastics, cross country running, rambling. You should normally refrain from certain sports such as riding, throwing sports, judo, football and karate in the first 4-6 months. The most important deciding factor in your particular case is once again your own sensible assessment of what you are physically capable of and avoiding placing any unreasonable strain on your body. Fitness for work: You will probably be unfit for work for about 4-6 weeks after you have been discharged from hospital. This also applies to housework. If you are still experiencing any residual pain or discomfort after this time, this can mean that a longer recuperation period is necessary. Fitness for work obviously depends on the amount of physical strain involved in the job you do. Heavy physical work should not be resumed until about 3 months after your operation. Having to retrain for another job is only necessary in a few exceptional cases. Sex: No special restrictions (avoid heavy physical stress). What else should be avoided in the first three months? Abrupt bending, lifting from a bending forward position, fast turning movements, working in the garden, sitting or driving for long periods, carrying heavy shopping, walking too far. In this rest and recuperation phase you should take care to eat sensibly, since putting on weight places a strain on your back.
Residual symptoms and relapse operations Residual symptoms If paralysis or sensory disturbance has existed for too long before surgery, there is a possibility that it will not cure itself completely. Despite improvements in the operating technique, it must generally be reckoned with that about 10% of patients do not lose their symptoms entirely. More or less pronounced dull back pain can persist, as well as shooting or burning pains in the legs. If this occurs, you should definitely return for an out-patient examination (please telephone in advance) to find out whether any other discs have become damaged. Relapse operations During your stay in hospital or afterwards, another prolapse - called a relapse - can occur and cause new, severe pain. Remaining pieces of the removed disc or the fibrous ring can put renewed pressure on the nerve endings. Although the danger of this happening is slight, a relapse after slipped disc surgery must be regarded as representing a certain risk which has to be taken into account. It occurs in 5-8% of all patients undergoing surgery. It is also possible for neighbouring intervertebral discs to become damaged, making further surgery necessary. Such a case, however, is not considered as a relapse, but rather as a new illness. These are all general recommendations, which may be subject to modification in particular circumstances, since each case is different and each patient therefore requires individual treatment. We would ask you to return to our out-patient department 8 weeks after you have been discharged from our hospital. If you have any further questions, please do not hesitate to contact us (patienten@aesculap.de).