Patients should seek emergency help if they developed neurological symptoms after neck manipulation, such as pain, dizziness, double vision, unsteadiness, slurred speech, nausea and jerky eye movements.

Experts have issued a new warning about the risk of strokes associated with neck manipulation to treat back pain.

Scientists highlighted a type of neck injury called a cervical artery dissection (CD) that can cause small tears in the walls of blood vessels in the neck.

This could result in clots blocking the flow of blood to the brain, leading to a stroke.

US neurologist José Biller, from the Loyola University, Chicago, who led a group of physicians writing in the journal Stroke, said: “Most dissections involve some trauma, stretch or mechanical stress.

“Sudden movements that can hyper-extend or rotate the neck – such as whiplash, certain sports movements, or even violent coughing or vomiting – can result in CD, even if they are deemed inconsequential by the patient.”

He pointed out that some manipulation techniques used to correct spinal misalignments and ease back pain involved extending, rotating and jarring the neck.

“Although a cause-and-effect relationship between these therapies and CD has not been established and the risk is probably low, CD can result in serious neurological injury,” he added. “Patients should be informed of this association before undergoing neck manipulation.”

Last year doctors writing on the British Medical Journal website also warned about the possible side effects of the treatments provided by chiropractors and osteopaths. They argued that the therapies were “unnecessary and inadvisable”.

Cervical artery dissection can result in serious neurological injury

Although case control studies had shown a link between CD and neck manipulation, they were not designed to prove cause and effect, Biller’s team said.

But the experts said patients should seek emergency help if they developed neurological symptoms after neck manipulation, including pain, dizziness, double vision, unsteadiness, slurred speech, nausea and jerky eye movements.

“Tell the physician if you have recently had a neck trauma or neck manipulation,” said Biller. “Some symptoms, such as dizziness or vertigo, are very common and can be due to minor conditions rather than stroke, but giving the information about recent neck manipulation can raise a red flag that you may have a CD rather than a less serious problem, particularly in the presence of neck pain.”