Disc Prolapse (Slipped disc)

A disc prolapse can occur throughout the spine but most commonly causes symptoms in the lower (lumbar) spine. It can cause back pain or, when pressing on a nerve, leg pain. This is called sciatica and is so named due to the distribution of pain along the sciatic nerve. Similar symptoms can occur if a prolapse occurs in the neck which may cause neck, shoulder or arm pain.

In the majority of people these symptoms will resolve in a matter of weeks with no intervention as the body heals itself and controls the inflammatory reaction associated with the prolapse. In this case, all that is suggested is a gentle return to comfortable activities, anti-inflammatory medication and pain killers as required.

Anti-inflammatory steroid injections may be useful to resolve symptoms sooner and surgery can be helpful in certain instances when pain is not controllable or has not resolved after a approximately 6-8 weeks.

What is a disc prolapse?

A prolapsed disc or slipped disc is not a true slip but rather occurs when the tough outer layer of the disc, the annulus, bulges or tears causing the soft nucleus to press on the nerves passing this region of the spine. Due to the combination of pressure and inflammation, that area around the disc and nerve becomes irritated and so the person experiences pain.

The brain interprets the pain as originating throughout the course of the nerve so in the lower spine that occurs in the leg (sciatica) and in the neck, the person experiences shoulder or arm pain (brachialgia). Bigger disc prolapses tend to cause more severe symptoms but it is not uncommon for a disc prolapse to be symptom-free and only picked up coincidentally when evaluating the spine for other reasons.

This is because when there is very little inflammation, there is often no pain. Asymptomatic disc prolapses need no treatment. Treatment is targeted at people experiencing pain.

Who gets a prolapsed disc?

Back pain is a common symptom and most people will experience back pain at some point in their lives. Only 5% of cases of back pain are caused by a prolapsed disc and only 5-10% of these may require surgical intervention. The reason for this is that back pain may have a number of causes and the disc is only one component of the spinal structure. The body also has a remarkable ability to repair itself.

There is a clear inheritance pattern to symptomatic disc prolapses so there is a higher incidence of prolapsed discs in families or siblings. The condition commonly occurs in men more than women and in the age group 20-50 years old.

Other factors such as smoking, obesity, major trauma and a previous disc prolapse may also increase a person’s risk of developing a future disc prolapse. It has not been shown that particular jobs or activities increase the risk of a prolapsed disc but a particular action such as sneezing or a sudden twist may be the final action that leads to a disc at risk of prolapsing, finally bulging out enough to cause symptoms.

Sedentary occupations or those that involve long periods of lifting or driving may cause other problems in the spine, such as muscle weakness. These problems may lead to the development of a disc prolapse in people at risk. Early physiotherapy aimed at strengthening the back and core muscles can be recommended to help prevent this occurring and thus prevent the need for surgery.

What are the symptoms of a disc prolapse?

Back or neck pain does occur and may precede the appearance of leg (sciatica) or arm pain (brachialgia) by a few days or weeks. Typically it starts suddenly and there may be an event or action that can be directly attributed to this such as a sneeze, twist or lifting something heavy.

This is then followed by limb pain which is typically all the way down the limb into the hand or foot. This is often described as a dull deep ache which may come and go depending on the position of the person and they may be able to find one position that is most comfortable, such as sitting or lying on one side. Depending on which nerve is affected, the distribution of pain may be different.

Apart from pain, people may also experience numbness, weakness or tingling/pins and needles and this is a reflection of the different ways the nerve is affected. These symptoms may come and go and typically the pain and tingling settles within a few weeks. Many people with a disc prolapse evident on a scan have no symptoms and these people need no treatment other that that aimed at caring for their spines in the form of the correct exercise and avoidance of activities and actions that could result in future problems.

What is cauda equina syndrome?

This rare condition occurs when a disc prolapse is particularly large and the nerves to the bladder and bowels are affected. The importance of this is that if these nerves are permanently affected it can result in long-term bladder or bowel control problems and incontinence.

Although extremely rare, if it does occur we know that early surgical intervention in the form of removal of the prolapsed disc and resultant pressure on the nerves can prevent long-term complications and so early recognition of the symptoms and presentation to a doctor is important.

The earlier the surgery the better. Once symptoms of incontinence have been present for a prolonged period, surgery is less effective.

Symptoms that may indicate that a disc is large enough or pressing on nerves to the bladder and bowels included sciatica stretching down the back of both legs and calves or going through periods of one leg then the other. Also numbness of the buttock area on both sides, typically that area we would normal sit on or the saddle area.

This can include numbness or tingling of the genital area or peri-anal region or the lack of feeling when using the toilet. Weakness of one or both legs could also indicate a large disc. Any of these symptoms should prompt urgent assessment by a doctor.

Once symptoms of inability to pass urine or being unable to feel or control the passing of urine occurs due to the presence of a disc prolapse, emergency surgery is indicated.

What is the typical course after a disc prolapse?

The vast majority of people will recover within 6-8 weeks with no intervention and only approximately 10% of people will require surgery. There is an incidence of recurrence so that after one episode, people are at risk of future episodes in the same or a different leg or arm.

By using anti-inflammatory medication and pain killers, symptoms can usually be controlled until the body’s natural healing ability resolves the prolapse and symptoms. Gentle return to activities of daily living are indicated but a few days of rest during the worst of the pain is entirely reasonable. If the pain symptoms do not resolve in a tolerable period or the pain is acute and not easily controlled with medication then an opinion from a spine surgeon may be helpful.

Is an x-ray or MRI scan needed?

Additional tests are not usually necessary for your doctor to make the diagnosis but are necessary to plan surgery. An MRI scan is the most sensitive way of seeing the disc prolapse. It shows exactly how the nerve is being affected and thus how to direct surgery or what surgery may be best suited to a particular person.

X-ray evaluation of the spine can be useful in certain cases of disc prolapse but in the majority of people is not required. Most abnormalities seen on X-ray or MRI scanning are part of the normal aging process of the spine and seldom require treatment so should not be performed without good indication and understanding of spinal conditions. They are completely unnecessary in people without symptoms or when symptoms have resolved.

What treatments are useful for sciatica or brachialgia?

Most people will recover fully without any intervention. It is suggested that they continue with regular activities as much as possible, avoiding those things that aggravate the symptoms. Resting for a few days may be useful, particularly when the sciatic or arm pain is at its worst.

Previously weeks of bed rest and traction in hospital was advised but now we have evidence that this does not help and may result in a prolonged recovery. It must be remembered that not all cases of back pain are due to a disc prolapse and treatments for back pain may differ from those for sciatica depending on the cause. If there is uncertainty as to the cause, advice from a doctor or physiotherapist would be helpful.

Medication

Medication that allows you to return to normal activities early is advisable and your doctor can suggest what is appropriate. These can be taken on their own or in combination. Broadly they fall into 3 categories

Paracetamol: this is a medication with few serious side effects and can be taken without prescription. People are still advised to refer to the advice found within the packaging regarding dosage and side effects.

Anti-inflammatory painkillers: these include ibuprofen, diclofenac, and naproxen and are aimed at reducing the inflammation that occurs with the prolapse. Side effects such as gastric irritation need to monitored and your doctor can advise on this. Some newer medication called COX-2 inhibitors may produce fewer side-effects and your doctor can advise if these will be suitable.

Painkillers: opiate type medication can serve as strong pain fillers and need prescribing by a doctor. These include codeine and tramadol but also include stronger pain-killers such as morphine. In situations when these stronger pain killers are required for long periods, side effects are more common and it is reasonable to consider a surgeon’s opinion as to whether a steroid injection may be useful.

Physical therapy.

In the acute stage of severe sciatica, it is unlikely that physical therapy (physiotherapy, chiropractic treatment or osteopathic manipulation ) will be tolerable and its benefit is thus debatable at this early stage. It is probably better to get the pain under control with medication and then consider physical therapy to hasten recovery and avoid a recurrence of symptoms or start physical therapy once the symptoms are resolving on their own.

Surgery

Surgery may be an option in cases where the pain is not resolving on its own after a period of approximately 6 weeks but this is not necessary in 90% of cases. Surgery may also be helpful if sciatica is recurrent or when episodes are resulting in prolonged periods of immobility or time off work. Should symptoms of cauda equina syndrome be present then an urgent opinion form a spinal surgeon should be sought as emergency surgery is the best treatment in this situation.

A surgeon may recommend a nerve root injection or epidural injection of steroid as a way of controlling symptoms but avoiding surgery. This is a way of introducing a steroid in the vicinity of the nerve affected by the inflamed disc and and as a steroid is a long-working anti-inflammatory medication, this may help control the pain while the body uses its own repair mechanisms to heal the prolapsed disc.

Injections are considered to be mostly safe interventions with few side effects and your spinal surgeon can advise you as to whether this is an appropriate form of treatment. Surgery in the form of a micro-discectomy is the standard treatment for a disc prolapse and in particular is aimed at removed the pressure on the nerve which then stops the pain

People that are already experiencing numbness and weakness often do not notice an improvement in these symptoms so this needs careful discussion with the surgeon prior to intervention. Resolution of pain however does occur in 90% of people that have surgery.

What long term treatment should I have after disc surgery?

Evidence does suggest that exercise and remaining active is the best way of recovery after surgery or an episode of sciatica. The best forms of exercise suitable can be recommended by a physiotherapist with expertise in back conditions.

The exercises are generally aimed at strengthening the back and core muscles and many exercise regimes such as pilates are developed to have a similar effect. A healthy lifestyle is beneficial which includes stopping smoking, healthy eating and losing weight if necessary.

Consider these sources of reliable information on caring for your back in the long term: Backcare ( the national back pain association)

The Back Book: written by a team consisting of a GP, orthopaedic surgeon, physiotherapist , osteopath and psychologist. It may be available through your GP or allied health professional or internet. Roland, MO et al. (2002) The Back Book. London: The Stationary Office.