Is it really sciatica?
Not all pain down the leg is sciatica,
but as it's about the only cause of leg pain most people have heard about, it's often what they most commonly self diagnose as the reason for their pain. In this respect it's quite similar to people calling any bad headache a migraine
or any elbow pain tennis elbow
, so over diagnosis is frequent.
Sciatic pain comes from irritation of the sciatic nerve, which runs from the lower part of our spine, through the buttock, down the back of the thigh and leg, usually a bit towards the outer edge. This is where the pain is felt and it's quite unique - more like a deep toothache or even 'electric' compared to simple muscular pain.
Pain down the side or front of the leg or thigh is not sciatic, and some pains in the right area may be due to referred pain from other structures such as spinal joints. This is a bit like neck pain causing referred pain in the shoulder - the location of the pain and the problem are not always the same. This is also true of a problem with the sacro iliac joint, which may refer pain there and/or in the groin or down the inside of the thigh.
Other nerves can also cause leg pain, pins and needles, numbness or even weakness. For example, the femoral nerve is associated with front of thigh pain, whilst the obturator nerve is related to an area on the inside of the thigh.
What causes it?
The nerve can be irritated by mechanical compression
from a tight muscle, often in the buttock, or a protruding disc pressing on it in the lower back, or by chemical irritation.
This may happen if a nearby structure in the lower back has been injured. The chemical 'soup' produced during the healing process of inflammation
is irritating in itself, but the accumulation of liquid pressure in the limited space of the spinal joint can also compress the nerve. In these cases, a course of anti inflammatory medication can be a great help in managing the symptoms.
|A real case study
This middle aged lady had a genuine case of sciatica that started soon after a trip some 3 months earlier, and which seemed worse in the morning. There had been one previous episode of the pain, but 6 years before.
Physio and osteopathy had given her some temporary relief. She did have low back pain, but that was overshadowed by the sciatic pain.
The cause could have come from a couple of areas in this case. Tests & X rays showed that compression of the nerve at the spine was very likely because the relevant disc was very worn. Since the disc acts as a thick rubber spacer and helps absorb shocks, a thinned disc leads to the vertebral joints being abnormally compressed.
In the long term, the joints become worn and roughened from this excess pressure. And in this patient this seemed to be the case because testing the joints would give her pain in the back of the thigh.
The inflammation from the damage would also explain why she felt her symptoms were worse on waking, because inflammation has a chance to build up during the night when we move around very little.
The outlook for complete recovery in these more extreme cases of wear and tear is not so hopeful, but in her case she was pain free after her 4th visit when she was due to see a specialist.
It is not known how she has been doing since, but this shows how it's always worth trying some treatment as a first step before making an expensive appointment with a specialist or surgeon.
If the degeneration has gone too far, it may be that the pain will never go completely, but that it can at least be kept to a manageable level.
Chemical irritation can come from an injured disc, for example from heavy lifting whilst leaning forwards, or from a prolapsed disc
. The difference is that with the latter, the disc material itself has ballooned out to one side to squash up against the nerve.
Sciatica in pregnancy
is common, and most likely due to the greater postural stresses on the lower back and buttock muscles. This stress comes not only from a growing baby, but also from the changed posture needed to compensate for the growing belly, and it's most visible in the typical backward lean of the heavily pregnant mother.
In older people, a longer history of sciatic pain may indicate that a condition known as stenosis
has set in. Stenosis just means a narrowing
of the tunnel through which the nerve passes coming out from the spine so that it is pinched. This is due to to irregular bone growth happening in a rather haphazard fashion. If everything else fails, surgery may be the only alternative to widen and smooth out the tunnels.
There are other less common but serious causes of sciatica which can not be treated with manual therapy, and these will need to be considered and ruled out during your consultation.
Can we help?
Unless the nerve irritation is from stenosis (see above), then the answer is usually yes.
The first step is to find the location and cause of the irritation; usually in the buttock or lower back. Most of the treatment will then focus on stretching and relaxing the muscles if that is the fault, or getting more movement in the affected spinal joint. De-compressing the nerve will also help recovery.