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A Systematic Review of Lower Limb Asymmetry After Anterior Cruciate Ligament Reconstruction in Adolescent Athletes
Get PDFAnterior cruciate ligament (ACL) rupture is a common athletic injury in adolescents which typically requires surgery to repair the injured ACL. Despite considerable efforts to improve outcomes, secondary ACL injury is common in athletes who return to sport. One of the main risk factors for secondary ACL injury is asymmetry in landing mechanics. The aim of this systematic review was to identify the common biomechanical asymmetries after ACL reconstruction in adolescents during landing. Sources were identified through searching databases using relevant search terms. Study titles and abstracts were screened using inclusion criteria which resulted in 13 articles being selected for further analysis. The methodological quality of each study was assessed independently by three reviewers. Asymmetry was more commonly identified in kinetic variables than kinematic variables. The most common asymmetries identified were peak knee extension moment and peak vertical GRF, both of which were frequently shown to be significantly lower in the surgical limb compared to the uninjured limb. These findings suggest that return to sport criteria following ACL reconstruction should incorporate analysis of the asymmetry in loading experienced by each limb rather than examining movement patterns alone
TRENDELENBURG TEST AND ACL RISK FACTORS DURING UNANTICIPATED CUTTING MANOEUVRE – A PILOT STUDY
Get PDFThe aim of this study was to find differences between the Trendelenburg test and risk factors for an ACL injury during a cutting manoeuvre in two age groups. Six female athletes divided into two groups (n3x2) participated in this study. Ten infrared cameras and force platform were used to collect the kinematic and kinetic data. The results of this pilot study suggest no hip weakness was observed in either group. The younger group had a larger difference between starting and finishing position during TT. In other side we found the higher values of the ACL risk factors in the older group
BIOMECHANICAL STUDY ON DIFFERENT DIRECTIONS FOR RUNNING JUMPS FOCUSED ON THE TAKEOFF PREPARATION
Get PDFThis study aimed to elucidate the difference in CG parameters from three steps, prejump to takeoff step of the jump motion (running jump), and obtain primary data on takeoff preparation action. Five male jumpers associated with the university track and field department were trained to perform their best at (1) approach run with no takeoff (RUN), (2) jumping as far as possible (long jump [LJ]), and (3) jumping as high as possible (high jump [HJ]), which were recorded using a three-dimensional capture system. As a result, significant differences were observed in not only the takeoff but also the takeoff preparation phase regarding CG parameters, suggesting the need to focus on the takeoff preparation phase as a factor that determines jump direction. Moreover, HJ and LJ suppressed an increase in vertical velocity one step prior, and by takeoff at a lower CG, the athletes allowed for an easier increase in takeoff angle and jump height. However, to resist a decrease in horizontal velocity, LJ transitioned to takeoff in a manner closer to RUN and without changing takeoff preparation as much as that in HJ. Thus, adjusting vertical velocity and height one step before takeoff can influence takeoff angle
A NOVEL METHOD TO DETERMINE STATISTICAL EFFECT MAGNITUDE USING SPM FOR GAIT ANALYSIS
Get PDFThe purpose of this research was to extend the typical SPM analysis of time varying human movement gait. We focused on the magnitude of statistical effect, with colour maps used to identify regions of high and low effect at the three-component vector level (3D joint kinematics and kinetics). Conceptually similar to a multivariate ANOVA, users can easily identify joints with the highest statistical effect, then probe the scalar components to determine which is most contributing to this effect. Though the analysis can be applied to any human movement biomechanics (i.e., running, walking, landing etc.), the example presented here is walking gait. Though only the kinetics from a single joint are presented, our goal is to build a user-friendly GUI capable of analysing the kinematics and kinetics of all joints and degrees of freedom in the kinematic and kinetic chain
THE IMPACT OF THERAPEUTIC ANKLE TAPING AND FOOT POSTURE ON THE KINEMATICS OF THE KNEE AND ANKLE WHILE RUNNING
Get PDFOverpronation is a misalignment of the calcaneus, contributing to overuse injuries in runners. Taping may control the position of the calcaneus to correct foot pathologies associated with overpronation. The purpose of this study was to explore the effect of therapeutic ankle taping and foot posture on the kinematics of the knee and ankle during running in participants with neutral and pronated foot types. Forty healthy participants ran on a treadmill with the application of Kinesio Tape®, Leuko Tape®, and no tape. A significant main effect for foot posture indicated that participants with a pronated foot type (p=.03) ran with a decreased amount of plantarflexion at the toe off phase of running when compared to a neutral foot type for all taping conditions. As plantarflexion occurs at toe off to propel the runner to the swing phase, a more rigid taping technique may be beneficial to provide support to the calcaneus
KEY FACTORS INFLUENCING BACK-SPIN PERFORMANCE IN CUE SPORTS
Get PDFThis study aimed to explore the key factors which influenced the performance of back-spin shots in cue sports. Nineteen male cue sports players with varied levels of playing experience were recruited. A back-spin shot test was administrated requiring participants to make the cue ball return to a specific area after potting an object ball. The performance of the back-spin test was evaluated by calculating an error distance using video analysis. The kinematics of the cue stick were determined using a 3D motion capture system. Multiple linear regression was applied to predict the performance of the back-spin shots based on selected kinematic variables of the cue stick. The results showed that the speed (p = .004) and height (p = .028) of the cue tip at impact were significant predictors of the back-spin performance. In conclusion, players should hit the lower part of the cue ball with high cue stick speed for better performance in a back-spin shot
RUNNING BIOMECHANICS IMPROVE FOLLOWING AN IN-SEASON INTERVENTION PROGRAM BASED ON PRE-TEST FUNCTIONAL MOVEMENT SCREEN SCORES IN COLLEGIATE DISTANCE RUNNERS
Get PDFThe purpose of the study was to determine if 12-weeks of correcting underlying movement patterns (stepping, squatting, lunging) would change running mechanics in college distance runners. 10 runners underwent pre and post Functional Movement Screen (FMS) testing and motion analysis of running kinematics [bilateral peak hip adduction (HADD), hip internal rotation (HIR), contralateral pelvis drop (CPD), rearfoot eversion (REV), ankle dorsiflexion (AKD) and knee flexion (KFLEX)]. They performed corrective exercises 3x/week based on FMS results. FMS (pre 14 + 1.5 vs post 16.4 + 1.8, p=.001) and left KFLEX (pre 36.4o + 11.3o vs post 42.2o + 5.2o, p=.024) significantly changed. Right and left HADD, HIR, and CPD decreased indicating a trend toward improvement. Results show that correcting underlying movement patterns shows promise to reduce pathomechanics
THE MODEL OF SHOULDER JOINT OF GYMNAST INTERACT WITH THE LONG SWING GYMNASTIC ELEMENT ON PARALLEL BARS
Get PDFThe purpose of this study was to identify the shoulder movement pattern which interacts with a long swing gymnastic movement (Belle). Four (4) national level gymnasts in China performed eight repetitions of movement (Belle), on the middle of parallel bars. Reflective markers (14mm) and ten high-speed cameras (ViconT40S,100Hz) were used to observe the time history of attached markers on the parallel bars and subjects. The coordinates of the necessary markers were calculated using ViconT40S digitizing software. The stiffness coefficient of the shoulder joints (KS=31667.5N.m-1) were estimated through the model. The reaction on the Humeral head (RS=194.45N) at the vertical position of under the bars is very much lower than the other places. This implied shoulders at the bottom of the motion should be flexible and soft.
KEYWORDS:stiffness of shoulder, Belle movement, Humeral head, parallel bars
UPPER LIMB KINEMATICS DURING THE TOPSPIN DOUBLE-HANDED BACKHAND STROKE IN TENNIS
Get PDFThe purpose of this study was to compare non-dominant wrist kinematics during tennis double-handed backhand strokes in players using either an eastern or continental grip position. Trajectory data for two grips (eastern & continental) and depths (deep & short) were captured for sixteen sub-elite right-handed tennis players using a 12-camera Vicon motion capture system (250 Hz). The eastern grip demonstrated significantly faster horizontal racket head velocities compared to the continental grip. However, no differences were observed in accuracy or spin rate between grips (p \u3e 0.05). In the non-dominant upper limb for the continental condition, elbow flexion was smaller while wrist extension was larger throughout the swing. Collectively, these data suggest that the continental grip may place the wrist in a position that is more vulnerable to overuse injury
CONSISTENCY AND VALIDITY OF ACUTE FOOT-STRIKE PATTERN ALTERATIONS DURING LABORATORY-BASED RUNNING
Get PDFDue to the limited learning time allotted in most foot strike pattern modification studies, the reliability of pattern alterations may be jeopardized. The purpose of the current study was to investigate the reliability and validity of requested acute alteration of foot strike patterns performed by participants in a laboratory environment. Participants employed a high degree of consistency within foot strike pattern conditions and across the steps within a condition (average within subjects 95% confidence interval = 0.5° - 4°). On a group level, participants accurately performed all foot strike conditions with the exception of the midfoot strike pattern. Thus, even with the alteration of foot strike pattern, a generally reliable and valid foot strike angle performance is evidenced