Synonyms in the wider sense
prolapsed intervertebral disc of the lumbar vertebrae, nucleus pulposus prolaps, NPP, Nucleus-pulposus-prolaps, disc prolaps, protrusion
Related terms: ischiadic pain, intervertebral disc bulge, intervertebral disc protrusion, lumbago, lumbaralgie, lumbago, lumbar ischiadical pain, back pain, intervertebral disc, intervertebral disc prosthesis
Definition
The term “prolapsed intervertebral disc” stands for the sudden or slowly progressing moving or escape of substance of the nucleus pulposus (jelly-like centre of the intervertebral disc) of one intervertebral disc backwards into the spinal channel or back and sidewards (nerve root). As a result of this, pressure on the nerve roots can cause pain, signs of paralysis and / or irritation of sensorial perception.
Prolapsed intervertebral discs occur more often within the lumbar vertebral column than the neck vertebral column.
Epidemiology
Back pain alone is no indication for a prolapsed intervertebral disc. It is generally very difficult to find the cause for back pain. Even x-ray cannot always provide the desired clarification.
In order to show that back pain and a pathological (morbid) prolapsed intervertebral disc do not necessarily go hand in hand, we here want to exemplarily look at the study by Jensen. This randomised, controlled study worked with MRT- examinations of the lumbar vertebral column and looked at people without pain. The results astonish:
With 52% of patients a protrusion of the intervertebral disc (= protrusion, intervertebral disc bulge) could be found.
With 27% a prolapsed intervertebral disc could be diagnosed, and 1% of the patients actually showed a prolapsed intervertebral disc that was already putting pressure on the surrounding tissue.
With 38% of patients the changes were not limited to just one intervertebral disc.
The frightening part is that only about 33% of all people examined mentioned back pain.
This shows that diagnostical accuracy can only be achieved, when all diagnostical methods are fully explored. It is always necessary to differentiate between different symptoms in order to achieve a
The intervertebral disc
Before we look at the prolapsed intervertebral disc, we should explain the term intervertebral disc. Only when the functions and the characteristics of the intervertebral disc are clear, can we understand the extent of the illness and the necessary therapeutic methods.
POSITION – where are intervertebral discs?
Between two vertebral bodies there is a cartilaginous connection that is called intervertebral disc. Because it is situated between two vertebral bodies, it is called inter-vertebral disc. Vertebral body and intervertebral disc are firmly joined together.
CHARACTERISTICS OF THE INTERVERTEBRAL DISC:
An intervertebral disc consists of the so-called annulus fibrosus, the outer ring made of connective tissue and cartilage, and the nucleus pulposus, the jelly-like inner centre. The humane body has altogether 23 intervertebral discs, which means that they together make up ¼ of the total length of the vertebral column.
The above described nucleus pulposus, the jelly-like inner centre, is under pressure. The consistency of the centre depends on the water balance of the intervertebral disc. The rule of thumb is:
“The more water it absorbs like a sponge, the fuller, more elastic and firmer it is.”
Accompanying we want to explain the process of full absorbtion.
The existence and decline of the water balance can be explained looking at the humane ageing process: during life the water content of the intervertebral disc is automatically reduced. This is made externally visible by the fact that the human gets smaller during the ageing process.
Also looking at yourself you can see that the same person is 1 – 3 cm taller in the morning compared to the evening, due to the fact that the intervertebral disc can relax through the nightly relief and reabsorb. It is like a wrung out sponge put in water that now absorbs to the full. And like a sponge the intervertebral disc gains in height.
The intervertebral disc however does not only need water, but also vital substances. Because the intervertebral discs do not get their nourishments from the blood stream, these vital substances can only be absorbed, if they are available and have been put forth through multiple human movements (bending backwards, circular movement of hips, walking, jogging, bending,…).
The following rule applies:
The more diversified the movements of a human are, the more intensive is the supply of this highly sensitive cartilaginous tissue with vital substances and water.
The following graphics show when the intervertebral disc absorbs water through relaxation and when it gives off water through strain.
STRAIN
It is through the intervertebral discs that the vertebral column gains its flexibility. Without them the vertebral column would be stiff, comparable to a broomstick. The intervertebral discs allow the elasticity and suppleness of the vertebral segments.
A change of bodily weight to the front, back or side provokes a moving of the nucleus in the same direction. Through this moving of the nuclei the cartilaginous ring, the so-called cartilaginous tissue disc, will be pressed together on one side and depending on the movement with varying strength; thus the pressure an intervertebral disc has to bear can vary tremendously.
The picture on the right should point out the different amount of strain that puts pressure on the intervertebral discs with different every-day movements. It is striking that the pressure on the intervertebral discs is the least, when lying on the back. Through false postures or false movements (middle right, below) the strain on the intervertebral discs increases. If the cartilage is already worn, a wrong movement like that can cause a prolapsed intervertebral disc. Wear and tear of cartilage is encouraged by ageing and / or loss of water.
Differentiation between prolapsed and protrused intervertebral discs
In the cause of a prolapsed intervertebral disc we differentiate between:
- Protrusion of the intervertebral disc (picture below), which causes the bulging of the annulus fibrosus
- Prolapse of the intervertebral disc (picture below) into the intervertebral holes or – more rarely – into the spinal channel
- Sequestration, in the consequence of which the prolapsed parts no longer are linked to the original disc
It can all be imagined as follows:
With a protrusion of an intervertebral disc the disc in itself stays intact. The inner jelly-like centre bulges to the front and thus puts pressure on the cartilaginous outer ring made of connective tissue.
With the prolaps of the nucleus pulposus however the jelly-like centre partly comes out of the outer ring. The part that comes out is still connected to the remaining inner jelly-like centre and does not encapsulate.
An encapsulation of the part that has come out happens during sequestration however: the prolapsed part of the jelly-like centre is no longer connected to the inner part.
Prolapsed parts of the intervertebral disc can put more or less pressure on the nerve root which immediately adjoins the intervertebral disc. In the lower part of the lumbal vertebral column that includes the ischiadical nerv, which under pressure can cause considerably strong pain (ischiadical pain).
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Vertebral disc:
- nucleus pulposus
- annulus fibrosus
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Protrusion of intervertebral disc:
- Nucleus pulposus
- Anulus fibrosus
- Protrusion of intervertebral disc
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Prolapsed / herniated intervertebral disc:
- Nucleus pulposus
- Anulus fibrosus
- Prolapsed intervertebral disc
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Cause
The intervertebral disc consists of a tissue ring with a jelly-like centre. In the case of a weakening or a tearing of the tissue ring due to wrong or over strain of the vertebral column, the jelly-like centre can come out of the intervertebral disc. This usually is caused by wear and tear; thus risk factors for a prolapsed intervertebral disc are adipositas and pregnancy.
Age and frequency
As already mentioned above the prolapsed intervertebral discs mainly occur in the lumbal part of the vertebral column, followed by the neck part; prolapsed intervertebral discs within the thoracal part of the vertebral column are relatively rare.
While lumbal prolapsed intervertebral discs mainly occur between the age of 30 and 50, those of the neck region peak later between the age of 40 and 60. A protrusion of the invertertebral discs can happen much earlier.
In the later stages of life prolapsed intervertebral discs occur less frequently, because then the loss of water within the intervertebral disc occurs (see above). In relation to the prolapsed intervertebral disc this bears the advantage that the jelly-like centre is more viscous and thus less able to prolapse.
Symptoms
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Picture MRT lumbal vertebral column
- intervertebral disc
- vertebral body
- spinal cord
- prolapsed intervertebral disc
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Which symptoms occur during a prolapsed intervertebral disc?
We have already mentioned the study above that showed that not every prolapsed intervertebral disc has to cause pain (back pain). If pain and symptoms occur with a prolapsed intervertebral disc, they are caused by the moving of the jelly-like centre that then puts pressure on single nerve roots, nerve-fibre-bundles (in the area of the lumbar vertebral column) and / or the spinal cord.
In the text that follows we will look at the symptoms that can vary depending on the pressure on the above mentioned areas.
Symptoms with pressure against a nerve root:
Pressure on nerve roots always causes intensive pain that can spread into the arms / legs. This intensive pain can be combined with an irritation of sensorial perception, namely: pins and needles, tingling and numbness. Depending on the stage and extent of the illness those symptoms can be followed by a weakening of the muscle power or even paralysis of individual muscle groups.
Symptoms with pressure against the spinal cord:
The symptoms vary according to the location of the prolapsed intervertebral disc. Prolapsed intervertebral discs within the thoracal vertebral column can cause irritation of sensorial perception, spasms or even paralysis, whereas a prolapsed intervertebral disc within the lumbar vertebral column can for example result in a paralysis of the bladder; also paralysis of the leg muscles is possible.
Symptoms with pressure on nerve fibre bundles (cauda equina):
Lack of control over the bladder and colon function, irritation of sensorial perception in the anal and / or genital region, the inner part of the upper legs and possibly even a paralysis of the legs.
Diagnosis
The diagnosis of the prolapsed intervertebral disc consists of different physical and machine-aided examinations. In addition to that other illnesses with similar symptoms have to be excluded through a differential diagnosis.
Neurological Examinations:
In order to diagnose or exclude a prolapsed intervertebral disc a thorough neurological examination is necessary. As part of the differential diagnosis it can for example help to exclude a disturbance of the blood supply or circulation of the legs, the so-called window-shopping-disease (= claudicatio intermittens).
Apart from that it enables to draw conclusions to the location, grade of the prolaps and the participating nerves.
A neurological examination tests the reflexes, the mobility, the sensitivity as well as the measurement of the nerve transport speed. This is especially important in order to judge the stage of the prolapsed intervertebral disc and to test, which nerve roots were damaged or what kind of circulation problem has occurred.
Conventional X-Ray:
2-LEVEL-SHOT:
An x-ray in at least two levels (from the front, from the side) allows to look at the bone structure of the vertebral column.
It is also possible to x-ray the patient in a functional shot. This special shot that can for example be done in an angle, which then allows conclusions regarding the flexibility of the vertebral column.
The problem with x-rays is that they only allow to look at the bone structure; the remaining soft tissue and the intervertebral discs can only be portrayed indirectly. Thus you can judge the vertebral column from its bone structure, but not – and that is especially important with a prolapsed intervertebral disc – the situation of the intervertebral disc and its individual problem.
Myelography
During a myelography contrast medium is injected in the nerve sack (dural sack). Through the contrast medium in the nerve sack the spinal cord including the nerve root in this sack can be made indirectly visible by leaving a blank space without contrast medium.
Due to the fact that nowadays we have good tomographic media, myelography is hardly put to use.
By using MRT and CT the best statements can be made with regard to size and localisation of a prolapsed intervertebral disc. Using CT however means a certain amount of radioactive contamination to the body.
Tomographic Diagnosis:
Computertomography and Magnetic Resonance Tomography show the spinal cord and the nerve roots. In order to differentiate between inflammatory and tumorous
disorders the additional injection of contrast medium is possible.
Therapy
Like with many illnesses there is the choice of conservative and surgical therapy. Which form of therapy is chosen, has to be determined in each individual case. We will briefly explain both therapeutical forms here. The therapy that is best for you does not depend on which one you prefer; your doctor will explain and recommend the best therapy for your individual case.
CONSERVATIVE THERAPY OF THE PROLAPSED INTERVERTEBRAL DISC:
Usually the first therapy is conservative, exceptions are acute, median prolapses that can cause severe damages and loss of motor and sensory abilities.
At first the vertebral column is relieved by bed-rest. This kind of immobilisation can last for 4 – 6 weeks. Based on the bed-rest back pain in the lumbar vertebral column may occur, that can be reduced by using a so-called step-bed.
In the case of a prolapsed intervertebral disc of the neck area the immobilisation can be achieved by using a neck-cuff.
Drug therapy
Drug therapy (pharmacotherapy) is an important part of the so-called pain therapy not only in relation to prolapsed intervertebral discs. Regarding the prolapsed intervertebral disc the most frequently used drugs are the non-steroid antiphlogistics (NSAR) like Ibuprofen, Diclofenac (Voltaren), Indometacine or COX-2-inhabitants (NO VIOXX!!!) in the form of tablets, capsules, suppositories, intramuscular injections or intravenous infusions.
A special anti-inflammatory, subsidising (anti-phlogistic) effect can be found in corticosteroids (cortisone). They should only be taken under the guidance and with the prescription of a doctor, when individual circumstances demand them.
The above mentioned drug therapy can also involve medical substances for the relaxation of muscles (muscle relaxants like Tetrazepam) capable of increasing the pain-reducing effect of non-steroid antiphlogistics. Relaxants minimize a part of the complaints by dissolving the muscle spasms.
If the illness has proceeded to a stage where the damage has reached the nerves in the periphery – as it is for example the case with a damaged nerve root -, the usage of antidepressants or anticonvulsive drugs can lift the pain barrier.
Chronic pain that is constantly there and does not function as a warn signal anymore – which is the original function of pain – can be eased by the prescription of opiates or opioids for example in the form of a so-called pain-plaster.
The taking of medical substances over a certain amount of time can result in possibly serious side-effects. For that reason self-medication is not an option! Every pain therapy belongs into the hands of a doctor. Only a trained doctor can decide the right form of therapy by judging the stage of the illness.
Physiotherapy / Medical Gymnastics:
By strengthening the back muscles through physiotherapy a better muscular conduction of the vertebral column can be achieved, that then also reduces the strain on the intervertebral disc. The physiotherapeutical measurements play a very important role within the conservative treatment of the prolapsed intervertebral disc. Please pay attention to the recommended literature.
Peridural Infiltration (PDI) and periradicular therapy (PRT):
By the means of peridural infiltration (PDI) or periradicular therapy (PRT) painkilling, anti-inflammatory and tissue-desolating medical substances are precisely injected in the pain-causing nerve root under computertomographic control. That leads to a damming of the mechanical inflammation around the nerve root and to a subsiding of the nerve. Sometimes within a prolapsed intervertebral disc you can observe a shrivelling of the moved intervertebral disc tissue. Whilst we use the PDI mainly for the lumbar vertebral column, the PRT rather applies for the neck area of the vertebral column. This is not a replacement for surgical therapy, but it can be used in the case of to other conservative treatments resistant pains with none or only minor neurological symptoms as an alternative therapy to surgery. Also pain after surgical treatment of prolapsed intervertebral disc can often be cured this way. This sort of treatment in the lumbar region does not necessarily need the use of CT.
Surgical therapy of prolapsed intervertebral disc:
Nowadays the indication for surgical treatment is only given reluctantly. Normally a direct advice for surgery is only given in the case of acute median mass prolapses in the area of the lumbar vertebral column that cause signs of paralysis. This is partly explained by the fact that conservative treatment bears a big chance for healing.
If a long conservative therapy brings no or hardly any results in the reduction of pain, we talk about a relative indication for surgery.
Generally a surgical treatment cannot prevent another prolapsed intervertebral disc. Also proliferating scar tissue can be in the way of surgical treatment.
Minimal-invasive treatment:
Due to the fact that traditional open surgery in general bears risks and means a longer stay in hospital, the so-called minimal-invasive surgical treatments have been developed. These minimal-invasive treatments can be done as an out-patient and with local anaesthetics, if the surrounding conditions are right. The risks that can never be excluded with a narcosis are reduced this way.
Minimal-invasive treatment does not apply in every stage of the illness. Traditionally this kind of treatment is used for simple and relatively new protrusions or prolapses of the intervertebral disc. Sequestration is not normally treated minimal-invasively.
Another exception for this form of therapy is pre-surgery. That means that patients who have already had surgery for a prolapsed intervertebral disc should not be treated with this method.
Traditional minimal-invasive methods are:
CHEMONUCLEOLYSIS
Chemonucleolysis means the chemical dissolving and subsequent sucking away of the inner jelly-like centre of the intervertebral disc.
REMOVAL OF THE INTERVERTEBRAL DISC VIA LASER:
Another therapeutical option is the removal of the intervertebral disc via laser. Similar to the above minimal-invasive treatment this method is only apt for uncomplicated, fresh prolapses.
This method is also based on the principle of volume reduction within the intervertebral disc and is done by the use of a medical YAG (Yttrium-Aluminate-Granate)-Laser.
PERCUTAN NUCLEOTOMY:
This method resembles the chemonucleolysis in the way that here, too, the volume reduction is achieved by sucking away the inner jelly-like centre. Different to the chemonucleolysis the dissolving is not done by an enzyme, but the prolapsed intervertebral disc is removed mechanically.
Micro-surgery:
Large wounds and big surgical areas mean a longer recuperation period for the patient; that is why minimal-invasive surgery tries to keep the surgical area as small as possible. This form of treatment is especially designed for the uncomplicated prolapsed intervertebral discs in the lumbar vertebral column. Through a minor incision the prolapsed intervertebral disc is cut out with the use of a microscope.
Conventional open surgery:
Difficult prolapsed intervertebral discs cannot be cured by minimal-invasive surgery. These are for example prolapsed intervertebral discs that concern neurofamina, prolapsed intervertebral discs that have existed for a longer period of time and are distributed over several storeys. In those difficult cases a bigger open access has to be chosen that allows a wider view into the surgical area.
In order to make this possible at least a part of the ligamentum flavum is removed, either on one or on both sides. This is called “windowing” and enables the access to the intervertebral disc and the concerning nerve root. If the nerve roots of two neighbouring storeys need to be presented, it might become necessary to remove a half arch of a vertebral body or even the whole arch. That way you can look at all the relevant structures and make them accessible for treatment. The prolapsed intervertebral disc can be totally or partially removed. Due to the extensive preparation the convalescence (recovery) is inevitably longer than with the micro-surgical procedure.
At the treated area the development of scar tissue is inevitable, like with all other surgical procedures; the extent of it is individually different. In unfavourable circumstances this scar tissue is susceptible to growth which in return can have a space consuming effect and put pressure on the nerves. In such cases another surgery might become necessary in order to reduce the scar tissue (postnucleotomysyndrome).
After the clearing of an invertebral disc storey a painful instability of the vertebral column may also develop. This may also make further surgery necessary, for example for a stiffening of the vertebral column.
Prosthesis of the vertebral disc:
In a growing number of cases prosthesis of the vertebral disc are inserted that are meant to copy the functionality of a normal intervertebral disc and to protect against the feared instability of the vertebral column.
So far the prosthesis of the vertebral disc are certified to have a long durability, but we are still missing more extensive studies. The importance of the prosthesis of the intervertebral disc will have to prove itself in the future, as well as the best type of prosthesis.
Propylaxis
There is no special prophylaxis protecting against a prolapsed intervertebral disc. The risk for one can be minimised however by changing or adapting the life-style, for example by strengthening the back muscles through exercise. Please note the recommended literature on this.
From my point of view exercise is the best and most important prophylaxis. Part of the changing and adapting is naturally also the correct posture with all activities at work and home. Thus heavy things should be picked up by squatting down with a straight back. When hoovering you can achieve a straight and relaxed working position by adjusting the hoover-pipe. If you have an occupation, where you sit most of the time, it makes sense to get up every now and again and walk about. Especially for this occupational group programmes with exercises for relaxation and loosening of muscles have been developed. And ergonomic adaption of the chair through height adjustment of the seat and back can also contribute to the protection of the vertebral column. This is also important for professional drivers.
Perspective / Prognosis
An exact prediction regarding the prognosis of an invertebral disc illness or prolapsed intervertebral disc is not possible. Older patients however tend to towards a chronicalisation of the pain, whereas younger patients show acute pain with longer intervals free of pain.
Thanks to modern therapeutical methods even a chronic illness can be made bearable for the patient. The extent of the improvement however hugely depends on the patient’s own initiative. Medical gymnastics are especially effective on the long run.
Please also pay attention to the related subject:
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