Musculoskeletal decompression sickness and risk of dysbaric osteonecrosis in recreational divers.

INTRODUCTION: Dysbaric osteonecrosis (DON) is a complication that usually occurs in professional divers or compressedair workers. Its correlation with a previous musculoskeletal decompression injury (i.e., 'limb bend') remains a controversial subject. There is little information about the prevalence of DON and its relationship to decompression sickness (DCS) in recreational divers.

METHODS: We undertook an observational, retrospective study of recreational divers treated for musculoskeletal DCS between 2004 and 2008 in three hyperbaric centres in the south of France using magnetic resonance imaging (MRI) following hyperbaric treatment.

RESULTS: Twenty-five (11.5%) musculoskeletal DCS cases were identified amongst 288 diving accidents treated during this period. Average age was 38 years with a mean body mass index of 26 kg/square m. Joint pains were located in the shoulder area in 21 divers, mainly in experienced male divers after performing repetitive long, deep dives with adequate decompression using dive computers. Twenty-one of 25 injured divers were examined by MRI of the affected area shortly after the accident. Six had initial humeral lesions compatible with ischaemic necrosis, but two repeat MRI examinations at three months did not reveal bone abnormalities. Increasing pain during hyperbaric treatment appeared to be the only factor associated with DON occurrence.

CONCLUSIONS: Musculoskeletal DCS in recreational diving is particularly seen in provocative dive profiles considered to carry a high risk for bubble production during decompression. The occurrence of this insult appears also to be related to other factors needing further study. The risk of early development of DON should not be ignored.