Sciatica

What causes sciatica?

Sciatic pain is often caused by a trapped nerve from a bulging disc (also called slipped disc, prolapsed disc and herniated disc in varying degrees of severity). The lowest discs in the spine are the most vulnerable as they are carrying the most weight and there is a narrowing of one of the important spinal ligaments here. Also the transition between the highly mobile lumbar spine and the immobile pelvis puts more mechanical stress at this level.

In sciatica problems the worst thing to have is numbness and weakness, not pain. If nerves, like the sciatic nerve, that come out of the spine get trapped the first thing to happen is pain as the nerve itself gets inflamed. If the compression on the nerve continues then you get tingling, pins and needles and eventually numbness and paralysed muscles in the leg. Interestingly you may not even have a sore back. If the compression is not relieved urgently, this can cause permanent problems. Often, however, sciatica and disc bulges are misdiagnosed.

Sciatica Symptoms

Sciatica Pain

In a study a while ago it was found that 40% of normal middle aged adults had a disc bulge on MRI scans and yet were not suffering from any adverse symptoms. So presumably many people who go to the GP with low back pain and sciatica due to say a lumbar joint problem, will have an MRI which shows a bulging disc completely un-related to their pain. This may account for the high failure rate of lumbar spine surgery to remove the offending disc bulge. The patient wakes up and the lumbar spine joint problem is still there.

Sciatica pain can start in the back and travels into the buttock, the back of the thigh and into the back or outside of the calf and finally into the outside or underneath of the foot and toes. The pain may skip some areas. If the pain is in the front of the thigh it is not sciatica. If the pain does not go beyond the knee it may not be sciatica either but simply a referred pain from a back muscle or joint. It is important to get a proper diagnosis as the treatments are different.

Many cases of sciatic nerve irritation are not caused by compression of the nerve at all. New research has shown that the damage around the nerve root may be due inflammatory changes. These changes may be caused by an auto-immune response or other chemical changes initiated by the body due to leakage of the jelly like interior of the disc into the spinal canal. If this is true, new drug treatment options may be coming along in the future. In the meantime, we are stuck with the traditional methods and chiropractic care may help.

Another theory is that emotional stress may play a role in some people. It is well recognised in the back pain research that stress and levels of happiness influence symptoms and the same may be true for sciatica. Perhaps the stress hormones are the key here as they can have a pro-inflammatory effect which would be like pouring petrol on the embers of inflammation from a disc bulge.

Sciatica Treatment

GP’s will often prescribe anti-inflammatory medication and pain-killers which can help. If things are not settling down within a few days more active treatment may be needed. Most chiropractors will use low back manipulation which frees up stiff joints, reduces adhesions and raises the pain threshold. Some studies have shown a reduction in the size of the disc bulge after manipulation which is encouraging.  Another technique which we use at Sundial is called Flexion-Distraction which, again, has some encouraging early studies and we have found helpful.

Flexion-distraction involves the patient lying face down on a special chiropractic bench which has a movable lower section. The chiropractor places one hand on the vertebra above the disc lesion and gently lower the patients legs creating a distraction stretch on the damaged area. Often people report that this brings immediate relief. This gentle up and down movement is repeated for a few minutes and is done 2 to 5 times a week for 2 to 4 weeks. If symptoms have improved well then treatment is stopped. If there has been some improvement but not enough then another 2 to 4 week trial is carried out. If no improvement is forthcoming then another treatment is used you may be referred back to you GP, especially if symptoms are still worsening.

A recent review on all forms of manual therapy found that there is moderately positive evidence that this manipulation is helpful for sciatica.

Sciatica Exercises

The most important thing for a quick and complete recovery is to stay as active as you can manage and to do the exercises that are prescribed. These will often be sit-ups and back extensions over a gym ball. This type of exercise strengthens the core stability trunk muscles and the tiny muscles in between the vertebrae themselves. This reduces the mechanical strain on the discs and joints and not only helps with recovery but also preventing it happen again.