Bare Bones Study in the UK

There is little discussion among those in the American sport diving industry of bone necrosis, a serious disease that causes bones to die. While there has been increasing evidence that it affects sport divers, it gets little discussion. After all, the suggestion that a long-term, lurking disease can affect people long after they stop diving is one way to throw a very wet blanket on the diving industry. And the thought that it may be related to longer and deeper diving is certainly an anathema to the emerging technical side of the industry.

Yet it’s a burning issue in the United Kingdom. The increased cases of bone necrosis in sport divers is seen as so serious that the United Kingdom Sport Diving Medical Committee recently issued this statement (which we have edited):

“Bone necrosis is a serious disease of bones that is also called avascular necrosis or dysbaric osteonecrosis. There are many causes, but exposure to hyperbaric conditions is the usual reason when it occurs in someone who dives or has dived in the past. Until recently it was thought to occur in only professional divers; however the UK Sport Diving Medical Committee has become aware of cases occurring in amateur divers. The Committee therefore wishes to bring this condition to the attention of all amateur divers.

“The disease can occur months, years or even decades after hyperbaric exposure. It causes areas of bone to die. If near a joint, it can result in severe joint damage and may make joint replacement necessary. When a dead area affects the shaft of a bone it causes no symptoms, but bone necrosis can change to a form of bone cancer.

“The cause of dysbaric osteonecrosis is unknown. There is no proven association with decompression illness, though both can affect joints and the risk of each condition is related to the degree of exposure to hyperbaric conditions. The incidence of dysbaric osteonecrosis increases with depths of dives, their duration and the number of exposures. Amateur sport scuba divers were considered to be at low risk because their dives were usually short and shallow. As amateur divers go deeper longer it is probable that more cases of dysbaric osteonecrosis will come to light. Failure to learn from past lessons may cause amateur divers to suffer an epidemic of bone necrosis, similar to those in caisson workers in the last century and in professional divers earlier in this century before safer work practices were introduced to those occupations.”

A member of the committee, Dr. Peter Wilmhurst, told DIVE magazine that he has treated three recreational divers for bone necrosis in the last year. “I have never before come across this illness in amateur divers, and other doctors are reporting similar cases. A new pattern is emerging.” The cases have spurred the UK Sport Diving Medical Committee to set up a registry of cases.

Would it not be prudent for the American diving industry, led by DAN, to take the same measure?

— Ben Davison

P.S. Dr. Wilmhurst can be contacted at Royal Shrewsbury Hospital, Shrewsbury, UK SY38XQ