Musculoskeletal Injuries Among Females in the Military: A Scoping Review

Load carriage changes tibiofemoral arthrokinematics during ambulatory tasks in recruit-aged women

The introduction of women into U.S. military ground close combat roles requires research into sex-specific effects of military training and operational activities. Knee osteoarthritis is prevalent among military service members; its progression has been linked to occupational tasks such as load carriage. Analyzing tibiofemoral arthrokinematics during load carriage is important to understand potentially injurious motion and osteoarthritis progression. The study purpose was to identify effects of load carriage on knee arthrokinematics during walking and running in recruit-aged women. Twelve healthy recruit-aged women walked and ran while unloaded (bodyweight [BW]) and carrying additional + 25%BW and + 45%BW. Using dynamic biplane radiography and subject-specific bone models, tibiofemoral arthrokinematics, subchondral joint space and center of closest contact location between subchondral bone surfaces were analyzed over 0-30% stance (separate one-way repeated measures analysis of variance, load by locomotion). While walking, medial compartment contact location was 5% (~ 1.6 mm) more medial for BW than + 45%BW at foot strike (p = 0.03). While running, medial compartment contact location was 4% (~ 1.3 mm) more lateral during BW than + 25%BW at 30% stance (p = 0.04). Internal rotation was greater at + 45%BW compared to + 25%BW (p < 0.01) at 30% stance. Carried load affects tibiofemoral arthrokinematics in recruit-aged women. Prolonged load carriage could increase the risk of degenerative joint injury in physically active women.

High Physical Exposure During Female Recruits' Basic Military Training in Sweden-A Descriptive Study

INTRODUCTION

There is a knowledge gap concerning the occurrence of physical complaints/injuries, i.e., musculoskeletal disorders (MSD), among Swedish women who undergo basic military training (BMT). The aims were to describe prevalence and factors related to MSD and explore physical exposure and performance in Swedish female recruits during BMT.

MATERIALS AND METHODS

A total of 144 females (mean age 22 years) who underwent BMT in 2016 participated in this cross-sectional study. Data regarding self-reported MSD, physical performance, physical activity and exercise, motivation and mental and physical preparation, and physical exposure during BMT and perceived health were collected at the end of BMT through the Musculoskeletal Screening Protocol questionnaire. Additional data on muscle strength were retrieved from IsoKai isokinetic lift tests. Descriptive and analytic (paired samples t-test and logistic binary regression) statistics were used.

RESULTS

The prevalence of MSD was high, with 33% (n = 48) reporting MSD before BMT, 78% (n = 113) during, and 50% (n = 72) at the end of BMT. Knee and upper back were the most frequently reported MSD locations. Forty-four (30%) participants felt insufficiently physically prepared for BMT. The physical exposure was high with loaded marches/runs and carrying heavy loads as the most demanding tasks. The longest walking distance was reportedly 55 km, and the reported maximum load was 50 kg. Forty-five participants (31%) had carried a load representing over 50% of their body weight. Most participants reported good to excellent health at the end of BMT. There was a small (8 N) but significant (P = 0.045) increase in mean force over time. Two variables, MSD before BMT (odds ratio 2.24, P = 0.03) and being physically unprepared (odds ratio 3.03, P < 0.01), were associated with MSD at the end of BMT.

CONCLUSION

This study showed that the prevalence of MSD in Swedish female recruits was high before, during, and at the end of BMT, with knee and upper back as the most frequent locations. Although the physical exposure during BMT was occasionally high, self-rated health was mainly perceived as good to excellent at the end of BMT. Previous MSD and being physically unprepared were related to MSD at the end of BMT. These important and relevant findings indicate the necessity for implementing interventions to increase physical fitness and treat MSD at the beginning of BMT.

Associations Between Rank, Sex, and Parity With Musculoskeletal Injuries Sustained During Annual Military Physical Fitness Test

ABSTRACT

Edwards, CM, da Silva, DF, Puranda, JL, Souza, SCS, Semeniuk, K, and Adamo, KB. Associations between rank, sex, and parity with musculoskeletal injuries sustained during annual military physical fitness test. J Strength Cond Res 38(2): 367-373, 2024-Musculoskeletal injuries pose a significant threat to the well-being of military personnel. Attempts to use physical employment standard test results as predictors of injury are underway, but little is known about injuries sustained during the tests. This study sought to identify body regions most likely to be reported as injured during the annual Canadian Armed Forces (CAF) physical fitness evaluation. In addition, sex, rank, and parity status are explored as possible associated factors for injury. A total of 1,796 actively serving CAF members were categorized by sex (1,030 male participants; 766 female participants), rank (1,142 Non-Commissioned Members [NCM]; 638 Officers), and parity (314 parous female participants; 435 nulliparous female participants). Sex, rank, and parity were associated with body regions reportedly injured during an annual CAF fitness assessment (significance p ≤ 0.05). When compared with male participants, female participants were more likely to be injured {aOR: 1.797 (95% [confidence interval] CI: 1.45-2.23)} and more prone to injury of the wrist (adjusted odds ratio [aOR]: 1.933 [95% CI: 1.20-3.12]), hip (aOR: 3.445 [95% CI: 2.07-5.728]), or lower back (aOR: 1.55 [95% CI: 1.18-2.04]). Non-Commissioned Members were more likely to injure the neck (aOR: 2.14 [95% CI: 1.18-3.88]) or shoulder (aOR: 2.03 [95% CI: 1.31-3.15]), when compared with Officers. Parous female participants reported pelvis/abdomen injury at a higher rate than the nulliparous group (5 vs. 1.7%, p = 0.019). Injuries sustained during an annual CAF fitness assessment differ based on sex, rank, and parity. Canadian Armed Forces female participants, NCM, and parous female participants may require specific physical fitness support in preparation for the annual physical fitness test.

Sex disparities in self-reported musculoskeletal injuries in the Canadian Armed Forces

Recent comprehensive systematic reviews indicate that females are at greater risk of musculoskeletal injuries (MSKi) than males in military populations. Considering the Canadian Armed Forces (CAF) goal of increasing female representation in the next few years, exploring these trends is essential. We aimed to determine the association between biological sex and MSKi in the CAF. An online survey was conducted with active-duty and former CAF members aged 18-65 years. Sex disparities in MSKi (acute or repetitive strain [RSI]) were analyzed using bivariate associations and binary logistic regressions with significance level at p < 0.05. Analyses were stratified by military environment (i.e., Army, Navy, and Air Force). From the 1947 respondents whose biological sex was reported, 855 were females and 1092 were males. Rates of RSI sustained by females and males while serving were 76.2% and 70.5% (p = 0.011), respectively, whereas 61.4% of females reported acute injuries compared to 63.7% of males (p = 0.346). Females were more likely to report overall RSI (adjusted odds ratio [aOR]: 1.397; 95% confidence intervals [CI]: 1.068-1.829), RSI having a greater impact on daily activities (aOR [95%CI]: 2.979 [2.093-4.239]) and greater impact on career progress/length (aOR [95%CI]: 1.448 [1.066-1.968]). Acute injuries, also more prevalent in females, were reported to have a greater impact on daily activities (aOR [95%CI]: 1.688 [1.198-2.379]). This study highlights sex disparities in MSKi prevalence and outcomes. Females within the CAF sample presented greater likelihood of reporting RSI, perceived impact of RSI on daily activities and career progress/length, and perceived impact of acute injuries on daily activities.

Characterization of Female US Marine Recruits: Workload, Caloric Expenditure, Fitness, Injury Rates, and Menstrual Cycle Disruption during Bootcamp

Basic training is centered on developing the physical and tactical skills essential to train a recruit into a Marine. The abrupt increase in activity and energy expenditure in young recruits may contribute to high rates of musculoskeletal injuries, to which females are more susceptible. To date, the total workload of United State Marine Corps (USMC) bootcamp is unknown and should include movement around the military base (e.g., to and from dining facilities, training locations, and classrooms). Thus, the purpose of this effort was to quantify workload and caloric expenditure, as well as qualitatively assess the impact of female reproductive health and injury rates in female recruits. Female recruits (n = 79; age: 19.1 ± 0.2 years, weight: 59.6 ± 0.8 kg, height: 161.6 ± 0.7 cm) wore physiological monitors daily throughout 10 weeks of USMC bootcamp. Physical fitness test scores, physiological metrics from wearables, injury data, and menstrual cycle information were obtained. Female recruits on average expended 3096 ± 9 kcal per day, walked 11.0 ± 0.1 miles per day, and slept 5:43 ± 1:06 h:min per night throughout the 10 weeks of bootcamp. About one-third (35%) of female recruits sustained an injury. In a subset of females that were not taking birth control and had previously been menstruating, 85% experienced cycle dysfunction during boot camp. High levels of physical activity and caloric expenditure, coupled with the stress of a new environment and insufficient sleep, may lead to alterations in female reproductive cycles and musculoskeletal injuries in young USMC recruits.

A Pilot Study on the Role of Experience and Patient Gender on MARCH Treatment Sequence

INTRODUCTION

The brevity of training for soldiers and combat medics to learn how to provide treatment on the battlefield may restrict optimal performance for treating chest and airway injuries, particularly when treating female soldiers. The present study tested treatment performance on patient simulators by battlefield medic trainees to determine whether there is a need for more extensive training on chest and airway procedures on female soldiers.

MATERIALS AND METHODS

Battlefield medic trainees treated male and female patient simulators in counterbalanced order. The assessment considered the effects of patient gender and order on procedures performed, particularly critical chest and airway interventions such as needle chest decompression (NCD), and considered the appropriate order of treatment tasks. Four coders rated video footage of three simulated procedures, i.e., tourniquet, chest seal (front and back application), and NCD, using a binary coding system to determine completeness and order correctness according to the Massive hemorrhage, Airway, Respiration, Circulation, and Head injury/Hypothermia (MARCH) mnemonic.

RESULTS

Results from analysis of variance showed that when presented with a female patient first, trainees performed significantly fewer total procedures on both the female and male simulators. More experienced trainees completed significantly more procedures compared to trainees with minimal experience. Results from the binary logistic regression showed that trainees with more experience and trainees presented with the male patient simulator first performed significantly more procedures in the correct order. Finally, an examination of the NCD procedure found that trainees presented with the female patient simulator first had more errors and that trainees with less experience were less likely to perform the procedure adequately.

CONCLUSIONS

The findings suggest that treating a female patient first may lead to undertreatment of both patients. Furthermore, the observed differences in treating sensitive areas of the body (e.g., near female breasts) suggest providing greater opportunities for trainees to practice often missed or incorrectly performed procedures. Treating a female patient remains a novel experience for many trainees, such that trainees are less likely to fully treat a female patient and are less likely to treat female soldiers for the most life-threatening injuries. In fact, the initial presentation of the female patient simulator appeared to affect experienced trainees, suggesting that removing the experience of novelty and stress requires more extensive exposure and alternative training. The study's small sample size with a wide range of trainee experience may limit the findings, which may fail to capture some study effects. Finally, the study did not request trainees' experience treating female soldiers, so future studies should examine the extent to which experience is predictive of performance. There is a need for more interactive approaches in patient simulations to provide opportunities for practice, especially those that require the treatment of sensitive areas.

A profile of injuries suffered by female soldiers serving in the Australian Army

Introduction

Female soldiers comprise an important component of any modern army, yet little research has been performed to investigate differences in the profiles of injuries reported by qualified female and male army personnel.

Aim

The aim of this study was to compare injury rates and patterns between female and male soldiers of the Australian Regular Army (ARA).

Methods

Data pertaining to all injuries reported by ARA members over a two-year period were accessed from the SENTINEL database and analysed descriptively. Findings regarding injury patterns were reported by most common location, nature, mechanism, and activity being performed at the time of injury. Injury incidence rates (IR) were calculated based on population size, and injury incidence rate ratios (IRR) comparing female and male injury rates were determined.

Results

A total of 8750 injuries were recorded across the two-year time period (2018–2020) of the study (minor injuries: n = 1766 female, n = 6870 male; serious injuries: n = 19 female, n = 95 male). Higher incidence rates of minor injuries were reported for female soldiers (IR = 20.75 injuries/100 soldiers/year) when compared to male soldiers (IR = 13.60 injuries/100 soldiers/year), with an IRR of 1.53 [95% CI = 1.46–1.60]. More serious injuries were reported at a similar rate between female (IR = 0.22/100 soldiers/year) and male soldiers (IR = 0.21/100 soldiers/year), with an IRR of 1.05 [95% CI = 0.65–1.72]. Female soldiers tended to report more ankle injuries than male soldiers who reported more knee injuries. Physical training and combat training were the most common causes of injury for both sexes.

Discussion

There were subtle differences in body locations of minor injuries within female and male soldiers. Both minor and more serious injury profiles were otherwise similar between sexes. Therefore, strategies required to minimise injuries in female soldiers may be similar in many respects to strategies required for male soldiers but require some differences to account for the subtle differences in body locations of injury, and so to ensure effectiveness across all personnel.