Some people claim it is the answer to back pain, others that it's a risky manoeuvre with serious side effects.

Tens of thousands of patients undergo spinal manipulation every year by osteopaths, chiropractors and physiotherapists in which the back or neck is "clicked" to relieve pain.

Today experts clash in the British Medical Journal over whether the risks are worth the benefits.

Neil O'Connell from Brunel University in London, and colleagues say research shows the manoeuvre carries a small but significant risk of tearing the lining of the vertebral artery or causing a stroke.

Yet the benefits are short term and do not provide lasting improvement.

The technique "may carry the potential for serious neurovascular complications" and is "unnecessary and inadvisable" they say.

Evidence suggests exercise is as effective as manipulation, without the risks. "The clear absence of unique benefit lead to the inevitable conclusion that manipulation of the cervical spine should be abandoned as part of conservative care for neck pain," they say.

David Cassidy, professor of epidemiology at the University of Toronto, Canada, and colleagues argue this would be tantamount to throwing the baby out with the bathwater.

They claim there is high quality evidence suggesting spinal manipulation can help patients with neck pain and it should be retained as a treatment option, along with other interventions such as exercise.

They call for further research to establish safe and effective treatments for the problem.

Back and neck pain are among the most common reasons for visits to GPs (after colds and flu). They affect one in three adults in the UK each year, with an estimated 2.5 million people seeking help from their GP.