Incidence and Mechanisms of Musculoskeletal Injuries in Deployed Navy Active Duty Service Members Aboard Two US Navy Air Craft Carriers

Introduction This brief report describes the number and nature of cases of musculoskeletal pain and injury among sailors and marines presenting to the ship's physical therapist during recent, respective deployments of two U.S. Navy aircraft carriers. Materials and Methods The case definition for this study was cases of work-limiting medical complaints involving the musculoskeletal system presenting, or referred, to the ship's physical therapy services for evaluation and treatment. The population for this study was drawn from ship's company from two Nimitz class carriers on their respective deployments. Potential subjects were recruited at their index visit for their complaint. Participants completed a survey of their symptoms while at the ship's medical department. Data for analysis consist of counts of cases, body part affected, self-reported mechanism of injury, age, and gender of the subject. Data were analyzed by generating descriptive tables. Results One hundred ninety-seven cases were captured across the two carriers. Injury to the low back was the most frequent (34%), followed by shoulder (25%) and knee (15%). Twenty one cases (11%) were reported to be exacerbation of previous injuries and the rest new injuries. Of the 176 new injury cases, 93 (53%) were of an insidious onset and the remainder had a specific, identifiable onset. Of the 82 cases with a specific identifiable onset, 38 cases (46%) occurred during participation in sport and exercise activity on board ship, and the remainder of the cases occurred during the performance of duty-related work. None of the cases required evacuation off of the ship. Conclusion Care should be used interpreting the results since participants were volunteers and a small proportion of eligible subjects chose not to participate in the study. Nevertheless, our data are generally consistent with other studies of musculoskeletal injury on board U.S. Navy ships and are useful for health care planning purposes and for planning for future studies that may take place on board U.S. Navy vessels. The novel and important finding of this study suggests that sports and exercise activity on board ship may warrant a new area of attention for safety.