Dysbaric osteonecrosis in recreational divers: a study using magnetic resonance imaging.

OBJECTIVE: We set out to identify whether magnetic resonance imaging (MRI) would identify evidence of dysbaric osteonecrosis (DON) in a group of experienced recreational scuba divers.

DESIGN: Local British Sub Aqua Club divers of at least Trainee Dive Leader grade were offered MRI scans (T1 and TIRM sequences) of hips, femora and shoulders. Anonymous images were interpreted separately by two radiologists, and cases not considered unequivocally normal were discussed for consensus opinion.

RESULTS: Of 26 divers imaged, five merited discussion. Four of these were considered to show unrelated normal variants or incidental findings. Only one case (abnormalities in the right humerus and left femur) could have possibly represented osteonecrotic lesions. After obtaining plain radiographs and more detailed clinical and dive history, these lesions were considered "indeterminate" but probably not DON by both reviewers and after taking further specialist musculoskeletal MRI opinion.

CONCLUSION: This study found no evidence that DON is a significant risk in recreational scuba diving and as such concurs with prevailing current opinion.