Risk Factors Associated With Musculoskeletal Injury: A Prospective Study of British Infantry Recruits.

BACKGROUND: Musculoskeletal Injury (MSKI), a common problem in both military and physically active civilian populations, has been suggested to result from both extrinsic and intrinsic factors. OBJECTIVE: To investigate prospectively whether gait biomechanics, aerobic fitness levels and smoking status as well as entry military selection test variables can be used to predict MSKI development during recruit training. METHODS: British infantry male recruits (n = 562) were selected for the study. Plantar pressure variables, smoking habit, aerobic fitness as measured by a 1.5 mile run time and initial military selection test (combination of fitness, Trainability score) were collected prior to commencement of infantry recruit training. Injury data were collected during the 26 week training period. RESULTS: Incidence rate of MSKI over a 26 week training period was 41.28% (95 % CI: 37.28 - 45.40%). The injured group had a higher medial plantar pressure (p < 0.03), shorter time to peak heel rotation (p < 0.02), current smoking status (p < 0.001) and a slower 1.5 mile run time (p < 0.03). In contrast, there were no significant differences (p > 0.23) in lateral heel pressure, age, weight, height, BMI and military selection test. A logistic regression model predicted MSKI significantly (p= 0.03) with an accuracy of 34.50% of all MSK injury and 76.70% of the non-injured group with an overall accuracy of 69.50%. CONCLUSION: The logistic regression model combining the three risk factors was capable of predicting 34.5% of all MSKI. A specific biomechanical profile, slow 1.5 mile run time and current smoking status were identified as predictors of subsequent MSKI development. The proposed model could include evaluation of other potential risk factors and if validated then further enhance the specificity, sensitivity and applicability.

Retrospective analysis of four-year injury data from the Infantry Training Centre, Catterick.

INTRODUCTION: Musculoskeletal injury (MSKI) represents a considerable threat to the effectiveness and productivity of military organisations globally. The impact on the medical chain, occupational disposal with associated loss of working days and associated financial burden have far-reaching consequence. The moral and legal responsibility to reduce avoidable injuries through risk assessment and prevention strategies is fundamental to governance and a key component of best practice. METHODS: A retrospective observational analysis was performed of 4101 MSKIs presenting from a total inflow of 10 498 British Army Infantry recruits recorded over four consecutive training years between 2012 and 2016. Injury incidence, site, type and week of training were recorded and analysed. RESULTS: The total incidence of all MSKI was observed as 39.1%. Overuse injuries were the most common subclassification of injury type (24.5%), followed by trauma (8.8%) and then stress fractures (5.7%). Causes of medical discharge over a four-year cumulative incidence were from overuse injuries (59.3%), stress fractures (21.5%) and trauma (19.2%). 45.5% of all MSKIs presented within the first eight weeks of training. CONCLUSIONS: MSKI data highlighted the requirement for a comprehensive service evaluation of the Combat Infantryman's Course and subsequent justification for the introduction of an injury prevention intervention - Project OMEGA.