ABSTRACT
OBJECTIVES: A history of childbirth is associated with musculoskeletal injury (MSKi) in female members of the Canadian Armed Forces (CAF). While previous injury and pregnancy impact knee kinematics, it is unclear if a history of childbirth is associated with medial knee displacement (MKD) in an overhead squat movement screen. The aim of this study is to examine the relationship between MKD and (1) MSKi and (2) parity status in female CAF members. METHODS: 24 nulliparous and 21 parous female participants employed by the CAF completed a comprehensive physical fitness assessment of muscular flexibility, power, strength, endurance, aerobic capacity and a bodyweight overhead squat movement screen (recorded using two-dimensional video, and hip-knee-ankle angle measured using Kinovea software). Interactions between MKD, parity status and MSKi history were assessed by one-way analysis of variance and two-way analysis of covariance (ANCOVA) (adjusted for age). RESULTS: An interaction between parity status and acute injury of the lower extremity was observed (F=4.379, p=0.043, η2 =0.099) in MKD of the right knee. The two-way ANCOVA examining acute injury of the lumbopelvic hip complex (lower back, pelvis, hip) yielded an interaction between acute injury to the lumbopelvic hip complex and parity status (F=4.601, p=0.038, η2=0.103) in MKD asymmetry. DISCUSSION: Parous participants with acute injury to the lower extremity had larger MKD than parous without this injury type. Parous participants without acute injury to the lumbopelvic hip complex had greater MKD asymmetry than nulliparous without this injury type. Our findings suggest that researchers and clinicians should consider parity status in conjunction with MSKi history when assessing knee kinematics in female military members.
ABSTRACT
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.
