Now showing 1 - 10 of 12
  • Publication
    Single-leg drop landing movement strategies 6 months following first-time acute lateral ankle sprain injury
    No research exists predicating a link between acute ankle sprain injury-affiliated movement patterns and those of chronic ankle instability (CAI) populations. The aim of the current study was to perform a biomechanical analysis of participants, 6 months after they sustained a first-time acute lateral ankle sprain (LAS) injury to establish this link. Fifty-seven participants with a 6-month history of first-time LAS and 20 noninjured participants completed a single-leg drop landing task on both limbs. Three-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment of force) data were acquired for the joints of the lower extremity, from 200 ms pre-initial contact (IC) to 200 ms post-IC. Individual joint stiffnesses and the peak magnitude of the vertical component of the ground reaction force (GRF) were also computed. LAS participants displayed increases in hip flexion and ankle inversion on their injured limb (P < 0.05); this coincided with a reduction in the net flexion-extension moment at the hip joint, with an increase in its stiffness (P < 0.05). There was no difference in the magnitude of the peak vertical GRF for either limb compared with controls. These results demonstrate that altered movement strategies persist in participants, 6 months following acute LAS, which may precipitate the onset of CAI.
      961Scopus© Citations 37
  • Publication
    Lower extremity coordination and symmetry patterns during a drop vertical jump task following acute ankle sprain
    Purpose: Evaluate the potentially adaptive movement patterns associated with acute lateral ankle sprain (LAS) using biomechanical analyzes. Methods: Thirty participants with acute LAS and nineteen controls performed a drop vertical jump (DVJ) task. 3D kinematic and sagittal plane kinetic profiles were plotted for the hip, knee and ankle joints of both limbs for the drop jump (phase 1) and drop landing (phase 2) phases of the DVJ. Inter-limb symmetry and the rate of force development (RFD) relative to bodyweight (BW) during both phases of the DVJ were also determined. Results: The LAS group displayed reduced ankle plantar-flexion on their injured limb during phase 2 of the DVJ, with greater associated inter-limb asymmetry for this movement (p < .05). The LAS group also displayed altered kinetic profiles, with increased inter-limb hip asymmetry for both phases of the DVJ (p < .05). This was associated with a decrease in the LAS participants’ injured limb RFD during phase 2 of the DVJ when compared with that of controls (11.76 ± 3.43 BW/s vs 14.60 ± 3.20 BW/s; p = .01, η2 = 0.14). Conclusion: Participants with LAS display potentially aberrant coordination strategies during a DVJ as evidenced by an increased dependence on the non-injured limb.
    Scopus© Citations 26  901
  • Publication
    Recovery From a First-Time Lateral Ankle Sprain and the Predictors of Chronic Ankle Instability: A Prospective Cohort Analysis
    Background: Impairments in motor control may predicate the paradigm of chronic ankle instability (CAI) that can develop in the year after an acute lateral ankle sprain (LAS) injury. No prospective analysis is currently available identifying the mechanisms by which these impairments develop and contribute to long-term outcome after LAS. Purpose: To identify the motor control deficits predicating CAI outcome after a first-time LAS injury. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Eighty-two individuals were recruited after sustaining a first-time LAS injury. Several biomechanical analyses were performed for these individuals, who completed 5 movement tasks at 3 time points: (1) 2 weeks, (2) 6 months, and (3) 12 months after LAS occurrence. A logistic regression analysis of several "salient" biomechanical parameters identified from the movement tasks, in addition to scores from the Cumberland Ankle Instability Tool and the Foot and Ankle Ability Measure (FAAM) recorded at the 2-week and 6-month time points, were used as predictors of 12-month outcome. Results: At the 2-week time point, an inability to complete 2 of the movement tasks (a single-leg drop landing and a drop vertical jump) was predictive of CAI outcome and correctly classified 67.6% of cases (sensitivity, 83%; specificity, 55%; P = .004). At the 6-month time point, several deficits exhibited by the CAI group during 1 of the movement tasks (reach distances and sagittal plane joint positions at the hip, knee and ankle during the posterior reach directions of the Star Excursion Balance Test) and their scores on the activities of daily living subscale of the FAAM were predictive of outcome and correctly classified 84.8% of cases (sensitivity, 75%; specificity, 91%; P < .001). Conclusion: An inability to complete jumping and landing tasks within 2 weeks of a first-time LAS and poorer dynamic postural control and lower self-reported function 6 months after a first-time LAS were predictive of eventual CAI outcome.
    Scopus© Citations 255  2496
  • Publication
    Single-leg drop landing motor control strategies following acute ankle sprain injury
    No research currently exists investigating the effect of acute injury on single-limb landing strategies. The aim of the current study was to analyse the coordination strategies of participants in the acute phase of lateral ankle sprain (LAS) injury. Thirty-seven participants with acute, first-time, LAS and nineteen uninjured participants completed a single-leg drop landing task (DL) on both limbs. 3-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment of force) data were acquired for the joints of the lower extremity, from 200ms pre-initial contact (IC) to 200ms post IC. The peak magnitude of the vertical component of the ground reaction force (GRF) was also computed. Injured participants displayed a bilateral increase in hip flexion, with altered transverse plane kinematic profiles at the knee and ankle for both limbs (p < 0.05). This coincided with a reduction in the net supporting flexor moment of the lower extremity (p < 0.05) and magnitude of the peak vertical GRF for the injured limb (21.82 ± 2.44 N/kg vs 24.09 ± 2.77 N/kg; p = 0.013) in injured participants compared to control participants. These results demonstrate that compensatory movement strategies are utilized by participants with acute LAS to successfully reduce the impact forces of landing.
    Scopus© Citations 35  1190
  • Publication
    Dynamic balance deficits in individuals with chronic ankle instability compared to ankle sprain copers 1 year after a first-time lateral ankle sprain injury
    Purpose: To quantify the dynamic balance deficits that characterise a group with chronic ankle instability compared to lateral ankle sprain copers and non-injured controls using kinematic and kinetic outcomes. Methods: Forty-two participants with chronic ankle instability and twenty-eight lateral ankle sprain copers were initially recruited within 2 weeks of sustaining a first-time, acute lateral ankle sprain and required to attend our laboratory 1 year later to complete the current study protocol. An additional group of non-injured individuals were also recruited to act as a control group. All participants completed the anterior, posterior-lateral and posterior-medial reach directions of the star excursion balance test. Sagittal plane kinematics of the lower extremity and associated fractal dimension of the centre of pressure path were also acquired. Results: Participants with chronic ankle instability displayed poorer performance in the anterior, posterior-medial and posterior-lateral reach directions compared with controls bilaterally, and in the posterior-lateral direction compared with lateral ankle sprain copers on their ‘involved’ limb only. These performance deficits in the posterior-lateral and posterior-medial directions were associated with reduced flexion and dorsiflexion displacements at the hip, knee and ankle at the point of maximum reach, and coincided with reduced complexity of the centre of pressure path. Conclusion: In comparison with lateral ankle sprain copers and controls, participants with chronic ankle instability were characterised by dynamic balance deficits as measured using the SEBT. This was attested to reduced sagittal plane motions at the hip, knee and ankle joints, and reduced capacity of the stance limb to avail of its supporting base.
    Scopus© Citations 78  1641
  • Publication
    Lower extremity function during gait in participants with first time acute lateral ankle sprain compared to controls
    Laboratory analyses of chronic ankle instability populations during gait have elucidated a number of anomalous movement patterns. No current research exists analysing these movement patterns in a group in the acute phase of lateral ankle sprain (LAS) injury. It is possible that participants with an acute LAS display movement patterns continuous with their chronically impaired counterparts. Sixty eight participants with acute LAS and nineteen non-injured participants completed five gait trials. 3D lower extremity temporal kinematic and kinetic data were collected from 200ms pre- to 200ms post-heel strike (period 1) and from 200ms pre- to 200ms post-toe off (period 2). During period 1, the LAS group displayed increased knee flexion with increased net extensor pattern at the knee joint, increased ankle inversion with a greater inversion moment, and reduced ankle plantar flexion, compared to the non-injured control group. During period 2, the LAS group displayed decreased hip extension with a decrease in the flexor moment at the hip, and decreased ankle plantar flexion with a decrease in the net plantar flexion moment, compared to the non-injured control group. These results indicate that participants with acute LAS display coordination strategies which may play a role in the onset of chronicity or recovery.
    Scopus© Citations 26  892
  • Publication
    Coordination and symmetry patterns during the drop vertical jump, 6-months after first-time lateral ankle sprain
    To evaluate the adaptive movement and motor control patterns of a group with a 6-month history of first-time lateral ankle sprain (LAS) injury during a drop vertical jump (DVJ) task. Fifty-one participants with a 6-month history of first-time acute LAS injury and twenty controls performed a DVJ task. 3D kinematic and sagittal plane kinetic profiles were plotted for the lower extremity joints of both limbs for the drop jump (phase 1) and drop landing (phase 2) phases of the DVJ. Inter-limb symmetry and the rate of impact modulation (RIM) relative to bodyweight (BW) during both phases of the DVJ were also determined. LAS participants displayed bilateral increases in knee flexion and an increase in ankle inversion during phases 1 and 2, respectively. They also displayed reduced ankle plantar flexion on their injured limb during both phases of the DVJ (p < 0.05); increased inter-limb asymmetry of RIM was noted for both phases of the DVJ, while the moment-of-force profile exhibited bilaterally greater hip extensor dominance during phase 1. Participants with a 6-month history of first-time LAS display some movement patterns consistent with those observed in chronic ankle instability populations during similar tasks.
    Scopus© Citations 23  510
  • Publication
    Locomotive biomechanics in persons with chronic ankle instabilityand lateral ankle sprain copers
    Objectives: To compare the locomotive biomechanics of participants with chronic ankle instability (CAI) to those of lateral ankle sprain (LAS) copers. Design: Cross-sectional study. Methods: Twenty-eight participants with CAI and 42 LAS copers each performed 5 self-selected paced gait trials. 3-D lower extremity temporal kinematic and kinetic data were collected for these participants from 200 ms pre- to 200 ms post-heel strike (period 1) and from 200 ms pre- to 200 ms post-toe off (period 2). Results: The CAI group displayed increased hip flexion bilaterally during period 1 compared to LAS copers. During period 2, CAI participants exhibited reduced hip extension bilaterally, increased knee flexion bilaterally and increased ankle inversion on the ‘involved’ limb. They also displayed a bilateral decrease in the flexor moment pattern at the knee. Conclusions: Considering that all of the features which distinguished CAI participants from LAS copers were also evident in our previously published research (within 2-weeks following acute first-time LAS); these findings establish a potential link between these features and long-term outcome following first-time LAS. Clinicians must be cognizant of the capacity for these movement and motor control impairments to cascade proximally from the injured joint up the kinetic chain and recognise the value that gait re-training may have in rehabilitation planning to prevent CAI.
    Scopus© Citations 27  919
  • Publication
    Gait Biomechanics in Participants, Six Months after First-Time Lateral Ankle Sprain
    No research currently exists predicating a link between the injury-affiliated sensorimotor deficits of acute ankle sprain and those of chronic ankle instability during gait. This analysis evaluates participants with a 6-month history of ankle sprain injury to affirm this link. 69 participants with a 6-month history of acute first-time lateral ankle sprain were divided into subgroups (‘chronic ankle instability’ and 'coper') based on their self-reported disability and compared to 20 non-injured participants during a gait task. Lower extremity kinematic and kinetic data were collected from 200 ms pre- to 200 ms post-heel strike (period 1) and from 200 ms pre- to 200 ms post-toe off (period 2). The ‘chronic ankle instability’ subgroup (who reported greater disability) displayed increased knee flexion during period 1. During period 2, this subgroup exhibited greater total displacement at their ankle joint and greater extensor dominance at their knee. That many of these features are present, both in individuals with acute ankle sprain and those with chronic ankle instability may advocate a link between acute deficits and long-term outcome. Clinicians must be aware that the sensorimotor deficits of ankle sprain may persevere beyond the acute stage of injury and be cognizant of the capacity for impairments to pervade proximally.
    Scopus© Citations 8  625
  • Publication
    Balance failure in single limb stance due to ankle sprain injury: An analysis of center of pressure using the fractal dimension method
    Instrumented postural control analysis plays an important role in evaluating the effects of injury on dynamic stability during balance tasks, and is often conveyed with measures based on the displacement of the center-of-pressure (COP) assessed with a force platform. However, the desired outcome of the task is frequently characterized by a loss of dynamic stability, secondary to injury. Typically, these failed trials are discarded during research investigations, with the potential loss of informative data pertaining to task success. The novelty of the present study is that COP characteristics of failed trials in injured participants are compared to successful trial data in another injured group, and a control group of participants, using the fractal dimension (FD) method. Three groups of participants attempted a task of eyes closed single limb stance (SLS): twenty-nine participants with acute ankle sprain successfully completed the task on their non-injured limb (successful injury group); twenty eight participants with acute ankle sprain failed their attempt on their injured limb (failed injury group); sixteen participants with no current injury successfully completed the task on their non-dominant limb (successful non-injured group). Between trial analyses of these groups revealed significant differences in COP trajectory FD (successful injury group: 1.58 ± 0.06; failed injury group: 1.54 ± 0.07; successful non-injured group: 1.64 ± 0.06) with a large effect size (0.27). These findings demonstrate that successful eyes-closed SLS is characterized by a larger FD of the COP path when compared to failed trials, and that injury causes a decrease in COP path FD.
      680Scopus© Citations 26