It's thought that up
to one in four cases may actually be caused by infection and not by
mechanical problems such as poor posture or improper lifting.
In a Danish study, more than half the patients were either cured or
much improved after 90 days of daily antibiotics. A much larger trial is
now under way, with results expected later this year.
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MRI scans of patients with herniated discs have
shown key changes in the vertebrae - the bone itself around the
affected area swells |
Lower back pain is one of Britain's biggest health problems. Every
year, nearly one in 12 adults consults a GP about it. Many patients
improve within three months of this initial visit, but up to 50 per cent
continue to suffer pain and disability.
Carrying heavy items and sleeping on soft mattresses are
common causes, but in many cases the problem is a herniated or slipped disc.
The discs, which are slotted between each of the vertebrae, are made up
of a hard, fibrous outer ring with a soft inner part called the nucleus.
The discs can degenerate with wear and tear; the outer
part then cracks, forcing the pulpy centre to bulge into the spinal canal.
This can irritate the nerves running from the spinal cord down the leg,
causing back pain and pins and needles down the leg.
Conventional treatments range from lifestyle changes and physiotherapy
to painkillers and surgery. However, it's thought bacteria may be
implicated, after MRI scans of patients with herniated discs have shown
key changes in the vertebrae - the bone itself around the affected area
swells. The scans showed that this occurs in up to seven out of ten
patients with a herniated disc. Patients with normal healthy discs do not
develop these changes.
In the pilot study, 29 patients with lower back pain and these bone
changes were given the antibiotic amoxicillin-clavulanate for three
months. Following treatment, 52 per cent of the patients reported that
they were much better or cured and 24 per cent were moderately better.
Nobody's symptoms worsened, although symptoms had been getting more severe
in the months before treatment. Researchers believe that when a disc
becomes herniated, bacteria can enter and cause an infection. That results
in an immune system response - the visible bone changes.
Other laboratory-based studies support this theory. In tissue removed
from damaged discs, more than half were infected with the bacteria
Propionibacterium acnes and Corynebacterium propinquum. Neither was found
in tissue from patients who underwent surgery for other back problems. But
where could the bacteria come from? Bacteria is found on the skin and in
the mouth, and frequently gets into the bloodstream through the gums;
brushing your teeth too vigorously can cause gums to bleed.
Usually the bacteria causes no problems - it is anaerobic, which means
it cannot grow in the presence of oxygen. But disc material, which has no
blood supply and hence no supply of oxygen, is an ideal breeding ground.
'When bacteria gets into the bloodstream, it can travel to the site of
a damaged disc; the body then reacts to the infection, resulting in lower
back pain,' says Dr Hanne Albert who has been leading the larger clinical
trial at the Back Research Centre in Denmark.
David Blake, professor of bone and joint medicine at the Royal National
Hospital for Rheumatic Diseases, Bath, says: 'If these results are
replicated and are significant in the placebocontrolled trial, it will be
a big step forward and comparable with the relatively recent discovery
that stomach ulcers can be caused by the bacterium Helicobacter pylori.
That was another big surprise to the medical profession, and it has
transformed the lives of millions.' Chronic pain sufferers have tested a
treatment which kept pain at bay for almost five weeks, writes Jenny
Hope. The intravenous therapy, called IVIG, is normally prescribed
for immune-system disorders. But doctors at the Pain Research Institute,
Liverpool University, found it helped almost 50 per cent of patients with
complex regional pain syndrome, a type of nerve injury that persists for
months after an injury or trauma to a limb. Twelve patients were given a
single, low-dose infusion of IVIG, antibodies taken from donated blood
plasma. Almost half had a 30 per cent reduction in their pain lasting five
weeks, and two patients had a 50 per cent reduction, says a report in
Annals of Internal Medicine.
Researcher Dr Andreas Goebel, senior lecturer in pain medicine, says it
is thought the treatment interferes with pain messages.
Roger Dobson - dailymail.co.uk
- Antibiotics are being investigated as a new
way to treat chronic lower back pain.