Effect of Sex and Ankle Brace Design on Knee Biomechanics During a Single-Leg Cut

Abstract

Background: Despite success at preventing ankle sprain, prophylactics that restrict ankle plantarflexion motion may produce deleterious knee biomechanics and increase injury risk. Purpose: To determine if ankle prophylactics that restrict plantar- and dorsiflexion motion produce changes in knee biomechanics during a single-leg cut and whether those changes differ between sexes. Study Design: Controlled laboratory study. Methods: A total of 17 male and 17 female participants performed a single-leg cut with 4 conditions: Ankle Roll Guard (ARG), lace-up brace, nonelastic tape, and an unbraced control. Peak stance knee flexion, abduction, and internal rotation joint angle and moment; total knee reaction moment (TKM) and its components (sagittal, frontal, and transverse); and ankle plantarflexion and inversion range of motion (ROM) and peak stance joint moments were tested with a repeated measures analysis of variance to determine the main effect and interaction of condition and sex. Results: Brace and tape restricted plantarflexion ROM as compared with ARG and control (all P < .001). With the brace, women had increased peak knee abduction angle versus ARG ( P = .012) and control ( P = .009), and men had decreased peak knee internal rotation moment as compared with ARG ( P = .032), control ( P = .006), and tape ( P = .003). Although the restrictive tape decreased inversion ROM when compared with ARG ( P = .004) and brace ( P = .017), it did not change knee biomechanics. Neither brace nor tape produced significant changes in TKM or components, yet sagittal TKM increased with ARG versus control ( P = .016). Women exhibited less ankle inversion ROM ( P = .003) and moment ( P = .049) than men, while men exhibited significantly greater frontal TKM ( P = .022) and knee internal rotation moment with the ARG ( P = .029), control ( P = .007), and tape ( P = .016). Conclusion: Prophylactics that restrict ankle plantarflexion motion may elicit knee biomechanical changes during a single-leg cut, but these changes may depend on prophylactic design and user’s sex and may increase women’s injury risk. Clinical Relevance: Sex-specific ankle prophylactic designs may be warranted to reduce knee injury during sports.

Differences in Biomechanical Determinants of ACL Injury Risk in Change of Direction Tasks Between Males and Females: A Systematic Review and Meta-Analysis

“…Nine studies utilised a 45° COD task [ 48 , 51 , 52 , 56 , 59 , 62 , 77 , 86 , 89 ], with two adopting a 60° sidestep [ 57 , 58 ]. Two studies adopted multiple COD angles including 45° and 110° [ 50 ], 45° and 180° [ 88 ], and 45–180° in four 45° increments [ 63 ].…”

“…One study each used isolated 90° [ 64 ] and 180° [ 61 ] CODs. Ten of the included studies included an anticipated COD task [ 48 , 49 , 52 , 57 , 59 , 61 , 63 , 64 , 86 , 88 ]; with one study examining both unanticipated and anticipated CODs [ 77 ]. Of the six studies utilising unanticipated conditions [ 50 , 51 , 58 , 62 , 85 , 89 ], a task choice approach was utilised requiring a decision between a 45°, 110° or straight run [ 50 , 51 ]; a 30° crossover cut and 60° sidestep [ 58 ]; a straight-line run, “hard stop” [ 62 , 85 ] or stop jump [ 89 ].…”

“…Scores ranged from 10 (55.5%) [ 50 , 58 , 64 ] to 16 (88.8%) [ 89 ]. Nine studies were below this mean score [ 48 – 51 , 56 , 58 , 59 , 64 , 77 ] with eight studies presenting greater methodological quality greater than the mean [ 52 , 57 , 61 – 63 , 86 , 88 , 89 ]. Between day reliability was reported in only one study [ 52 ].…”

“…All but one study [ 64 ] clearly defined athlete demographics and outcome variables. Six studies did not include information surrounding familiarisation of the athletes to the COD task to be performed [ 48 – 51 , 59 , 88 ]. Eight [ 50 , 51 , 58 , 59 , 62 – 64 , 77 ] of the 17 included studies conducted inappropriate statistical processes when examining differences between males and females in COD biomechanics, through pooling data across tasks [ 50 , 62 – 64 ], maturation [ 51 ], fatigue [ 58 , 77 ] and bracing [ 59 ] protocols prior to performing statistical analysis.…”

“…In randomised controlled trials or studies examining the effect of an intervention such as bracing [ 59 ] or fatigue [ 58 , 77 ], only baseline data from the control group were extracted for subsequent analysis. Exclusion criteria consisted of studies examining injured or ACL reconstructed populations, case studies, and poster presentations/ conference proceedings.…”