Risk Factors of Dysbaric Osteonecrosis in Saturation Diving Identified through Magnetic Resonance Imaging Surveillance.

Abstract

Introduction: Only a few cohort studies have investigated dysbaric osteonecrosis (DON) in saturation diving (SD) divers using magnetic resonance imaging (MRI) to detect early-stage DON. We aimed to investigate DON in the Japan Maritime Self-Defense Force (JMSDF) deep SD divers using MRI and examined the relationship between DON and the risk factors.

Methods: This study included 62 JMSDF SD divers. DON was diagnosed in the subjects' shoulders, hips, and knee joints using MRI and their clinical information. We analyzed subjects' diving records, including pre- and post-diving medical check information such as decompression sickness (DCS) and pain +/-. Data from the annual JMSDF health checks were analyzed to identify risk factors for DON based on divers' predispositions, lifestyles, and diving profiles.

Results: Of the 62 saturation divers (mean age: 40.61±6.93 years), three (4.8%) showed evidence of DON. MRI showed a geographic lesion with symptoms or a history of DCS. Two divers with DON had knee pain and a history of DCS. Furthermore, one asymptomatic diver and another diver with pain were heavy drinkers. Regarding physical and biochemical examination, diastolic blood pressure and high-density lipoprotein-cholesterol were identified as significant risk factors in an unpaired t-test (DON+ vs. DON-).

Discussion: Our findings suggest that SD is associated with a higher risk of DON, the early stage of which can be detected using MRI. The possible risk factors for DON were a previous history of DCS, diastolic BP, and HDL cholesterol, suggesting that ischemia could be involved in DON pathogenesis.