Surgeons in the UK and elsewhere are reviewing how they treat patients with chronic back pain after scientists discovered that many of the worst cases were due to bacterial infections. The finding means that some patients with unrelenting lower back pain mayl no longer face major operations but can instead be cured with courses of antibiotics. One of the UK’s most eminent spinal surgeons said the discovery was the greatest he had witnessed in his professional life, and that its impact on medicine was worthy of a Nobel prize. “This is vast. We are talking about probably half of all spinal surgery for back pain being replaced by taking antibiotics,” said Peter Hamlyn, a consultant neurological and spinal surgeon at University College London hospital.

Specialists who deal with back pain have long known that infections are sometimes to blame, but these cases were thought to be exceptional. That thinking has been overturned by scientists at the University of Southern Denmark who found that 20% to 40% of chronic lower back pain was caused by bacterial infections.

“This will not help people with normal back pain, those with acute, or sub-acute pain – only those with chronic lower back pain,” Dr Hanne Albert, of the Danish research team, told the Guardian. “These are people who live a life on the edge because they are so handicapped with pain. We are returning them to a form of normality they would never have expected.”

The Danish team describe their work in two papers published in the European Spine Journal. In the first report, they explain how bacterial infections inside slipped discs can cause painful inflammation and tiny fractures in the surrounding vertebrae. Working with doctors in Birmingham, the Danish team examined tissue removed from patients for signs of infection. Nearly half tested positive, and of these, more than 80% carried bugs called Propionibacterium acnes. The microbes are better known for causing acne. They lurk around hair roots and in the crevices in our teeth, but can get into the bloodstream during tooth brushing. Normally they cause no harm, but the situation may change when a person suffers a slipped disc. To heal the damage, the body grows small blood vessels into the disc. Rather than helping, though, they ferry bacteria inside, where they grow and cause serious inflammation and damage to neighboring vertebrae that shows up on an MRI scan.

In the second paper, the scientists proved they could cure chronic back pain with a 100-day course of antibiotics. In a randomized trial, the drugs reduced pain in 80% of patients who had suffered for more than six months and had signs of damaged vertebra under MRI scans.

Albert stressed that antibiotics would not work for all back pain. Over-use of the drugs could lead to more antibiotic-resistant bacteria, which are already a major problem in hospitals. But she also warned that many patients will be having ineffective surgery instead of antibiotics that could alleviate their pain.”We have to spread the word to the public, and to educate the clinicians, so the right people get the right treatment, and in five years’ time are not having unnecessary surgery,” she said.

Hamlyn said future research should aim to increase the number of patients that respond to antibiotics, and speed up the time it takes them to feel an improvement, perhaps by using more targeted drugs.