E. Canetti1,2, B. Schram1,2, R. Orr1,2, R. Pope3,2
1Bond University, Faculty of Health Sciences and Medicine, Gold Coast, Australia, 2Tactical Research Unit, Bond University, Gold Coast, Australia, 3Charles Sturt University, School of Community Health, Albury/Wodonga, Australia

Background: Osteoarthritis (OA) is a degenerative multifactorial debilitating musculoskeletal condition. Occupations with high physical demands, such as the military, have been associated with an increased risk for developing, and worsening, lower limb OA. The burden of OA in military occupations, such as air force officers, is not limited to the cost of training, which can be over one million US dollars per pilot, for example, but extends to deficits in combat readiness and capabilities.

Purpose: To
a) analyse the exposure of Australian Air Force Officer Cadets to occupational tasks associated with an increased risk of developing lower limb OA, and
b) identify projected timeframes for Air Force officers to reach threshold exposures that may increase risk of developing lower limb OA.

Methods: A Job Exposure Matrix was developed using training program, observation, survey data collected from the Initial Officer Course (IOC). Data included activities undertaken within the program and their durations, distances traversed by trainees, and loads lifted or carried by trainees.  From these, a desktop analysis was performed to identify the frequencies and durations of exposures during the 17-week course to physically demanding occupational tasks reported by the Australian Repatriation Medical Authority’s (RMA) Statements of Principles to be associated with increased risk of developing lower limb OA (i.e. lifting or carrying loads >20kg, climbing >150 stairs, kneeling/squatting >1hour). Projected cumulative exposures were then estimated, assuming that average weekly exposures identified in the IOC would continue as personnel moved into the operational roles for which they were trained.

Results: It was estimated that within 7 years 31 weeks following commencement of service, Air Force officers would reach the threshold exposure specified by the RMA under its ‘reasonable hypothesis’ scenario for increased risk of lower limb OA, based on having lifted weights of over 20kg to a cumulative total of 100,000kg within a 10-year period of service. Exposures to carrying, climbing stairs, kneeling and squatting during the IOC were insufficient to reach any of the RMA-specified thresholds for the development or clinical worsening of lower limb OA.

Conclusion(s): Cumulative exposures to lifting heavy weights (>20kg) may increase the risk of Australian Air Force officers developing lower limb OA.

Implications: Review of officer training practices should aim to reduce heavy lifting (>20kg) while weight bearing through legs, where possible, to support workforce preservation and veteran wellbeing. Where such occupational demands are unavoidable, efforts should be aimed at reducing other risk factors for lower limb OA, such as high BMI and history of previous injury.

Funding, acknowledgements: This project was funded by a grant awarded by the Department of Veterans' Affairs.

Keywords: exposure, osteroarthitis, occupation

Topic: Occupational health & ergonomics

Did this work require ethics approval? Yes
Institution: Bond University
Committee: Bond University Human Research Ethics Committee
Ethics number: RP02290

All authors, affiliations and abstracts have been published as submitted.

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