There is good news for people suffering from Complex Regional Pain Syndrome (CRPS), a serious condition affecting a limb after an – often small – accident or operation.

Researchers have now come closer to discovering the cause of the syndrome, raising hope of findings a treatment.

“The CRPS is a serious condition which is not fully understood. The findings of this study hint at a cause for it – harmful serum-autoantibodies – and raise the possibility of finding a treatment,” said Andreas Goebel from University of Liverpool in Britain.

Although it had previously been thought that the cause of CRPS is exclusively an abnormal brain activity after injury, the study points to an immune dysfunction.

“It is quite possible that CRPS is caused by a fault in the immune system. This study seems to pinpoint the cause as autoantibodies, and by examining this area further we can look to developing a cure,” Goebel added.

CRPS can cause severe pain lasting many years, as well as limb swelling, hair and nail growth changes, and muscle atrophy, but until now there has been no clear evidence of the cause.

For the study, researchers transferred antibodies from the serum of patients with CRPS to mice, causing many of the same symptoms to be replicated.

The findings appeared in the journal Pain.