Does science support surgery for sciatica?
What is Sciatica?
Many patients will see a chiropractor because they have sciatica. Sciatica is a commonly used term but its meaning can sometimes be confused. True sciatica is pain that emanates from the back and runs from the buttock down the back of the thigh and calf and often into the foot. This pain follows the pathway of the sciatic nerve and its branches. The pain is commonly associated with numbness down the back or side of the leg and weakness in the muscles of the calf or foot. Health care professionals will usually diagnose the problem according to the particular spinal nerve that is the likely cause and the side of the body that is affected. The term radiculopathy is generally used in the diagnosis for example a left L5 radiculopathy, which means the 5th Lumbar nerve on the left side is being inflamed or compressed. Sciatica can be felt down both legs and this can represent a more severe problem.
Slipped or bulging discs
The vast majority of (around 90%) of cases of sciatica are caused by a bulging or “slipped” disc (or herniated disc) in the lower back. In reality discs do not slip out, they have a tough outer “bark like” layer and a thick “gel like” substance inside. There are various risk factors associated with developing a disc herniation risk factor is being between the ages of 35 and 50.
These risks are, gender- men have roughly twice the risk of developing a lumbar (lower back) herniated disc compared with women, Physically demanding work, whole body vibration (bus drivers etc), Obesity, Smoking, Family history (genetics).
In cases of sciatica over months or years the gel can start to be squeezed back towards the nerves of the spine and at some point this can result in the pain and problems described above. Less frequently sciatica can be caused by “wear and tear” related narrowing of the spine called stenosis. Fractures and tumours make up an even smaller proportion of cases of sciatica.
Cauda Equina Syndrome
In rare circumstances (incidence of 1 in 33, 000-1 in 100 000 in the population) there can be numbness that develops around the backside and genitalia and loss of normal control of the bowel, bladder and sexual dysfunction may occur. These problems are caused because of compression of a collection of nerves at the base of the spine known as the cauda equina (“horses tail“) and the term used for the resultant loss of function of these nerves and bodily systems is termed cauda equina syndrome.
Cauda equina syndrome is requires emergency decompression surgery to be performed to minimize the risk of permanent loss of function of these bodily functions which will often occur after around 72 hours of the development of cauda equina syndrome.
The good news is that if decompression surgery is performed in this time frame the outcomes are favourable. So for these patients surgery is undoubtedly the best option and the sooner the better.
Many patients wish to have an MRI or other imaging when they have sciatica. Imaging is only recommended if patients haven’t improved after 6-8 weeks of conservative treatment (advice, painkillers, rehabilitation exercise and hands on treatment). The exception to this is if a patient displays “red flag’ in their history.
The good news is that the majority of patients will recover, the pain will go and the nerve function will return to normal or very near normal. In cases where people have worsening weakness or numbness in their leg or foot and a “slipped disc” appears the likely cause when considering a detailed examination and MRI findings (not MRI findings alone) then surgery may be considered.
Studies that have looked at hundreds of cases of patients with sciatica have shown that after 12 months those having surgery are generally no better off than those patients who have not had surgery. Some studies have suggested that in severe cases of sciatica patients have improved more quickly if they have had surgery, but again after 12 months they aren’t better off than those who have not had surgery.
Research studies do not always look at all the details of each individual case. If you are in this situation it’s important to have a discussion with the various healthcare professionals who are looking after you. Together with them, you can make the best decision for your individual case. Clearly having even minor surgery to the spine has some risk associated with it, so the likely benefit of having the surgery has to outweigh the risks for it to be the right course of action. The vast majority of people who have sciatica do not require surgery.
The final point is that if patients are still experiencing a lot of pain and disability, despite having all the usual conservative treatment, they may be offered an injection into their back. This is either around the nerve thought causing the sciatica a “nerve root block” or an injection that can help with pain in the back and more than 1 nerve known as a caudal epidural. These injections can and do help a lot of patients, but that’s a topic for a separate article.
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If you would like to discuss your back or leg pain feel free to contact us.