History Of Lower Extremity Injury Research Articles

Interpersonal Coordination between Female Soccer Players: Leader-Follower Roles within a Collision-Avoidance Task.

Return to sport decision-making may be improved by assessing an athlete's ability to coordinate movement with opponents in sport. The purpose was to investigate whether previous injuries associated with female soccer players' interpersonal coordination during a collision avoidance task. The authors hypothesized that external perturbations would disrupt the strength and stability of coordinated movement, and that individuals with a history of injury would be less likely to recover coordinated movement. Cross-Sectional. Nine female athletes with a history of lower extremity injuries and nine without injuries were paired into dyads. Each dyad completed twenty trials of an externally paced collision-avoidance agility task with an unanticipated perturbation. Participant trajectories were digitized and analyzed using cross-recurrence quantification analysis (CRQA) to determine the strength and stability of interpersonal coordination dynamics. Trials in which participants with injury history assumed leader or follower roles within each dyad were then used to study how dyadic coordination varied across task stages (early, perturbation, and late) using linear mixed effect models. Cohen's d effect sizes were calculated to demonstrate magnitude of differences. In exploratory analysis, psychological readiness (i.e., self-reported knee functioning, fear of injury, and risk-taking propensity) was evaluated for their association with leader-follower status. Perturbation disrupted the strength (R2=0.65, p<0.001, early=49.7±1.7, perturbation=41.1±1.7, d=0.39) and stability (R2=0.71, p < 0.001, early=65.0±1.6, perturbation=58.0±1.7, d=0.38) of interpersonal coordination regardless of leader-follower status. Individuals with injury history failed to restore coordination after the perturbation compared to control participants (injury=44.2.0±2.1, control=50.8±2.6, d=0.39). Neither demographic nor psychological measures were associated with leader-follower roles (B=0.039, p=0.224). Individuals with a history of lower extremity injury may have a diminished ability to adapt interpersonal coordination to perturbations, possibly contributing to a higher risk of re-injury. 3.

Impact of Differing Instability Devices on Postural Sway Parameters

Single-limb balance training is integral to preventing and rehabilitating lower extremity injuries. Previous investigations have shown that when using instability devices, differences may or may not exist in the postural sway parameters during use, depending on the specific devices being assessed. Thus, this investigation sought to examine the differences between a commonly used foam pad and a novel instability device (block) in postural sway measures. Twenty-two healthy individuals with no history of lower extremity injury or neurological disorders participated in this investigation. The participants performed three single-limb static balance exercises on a force platform sampling at 120 Hz. Each condition contained three 10-s trials separated by thirty seconds. The mean CoP values of the three trials in each condition were then compared using a within-subjects repeated-measures analysis of variance. Statistically significant differences were seen in the sway area between conditions (p = 0.009), the CoP path length (p = 0.007), the peak medial–lateral CoP displacement (p = 0.004), and the average sway velocity (p = 0.007). All variables displayed similar trends whereby the control condition showed significantly lower values than both instability devices, with no differences between devices. This investigation provides supporting evidence that different instability devices may deliver similar changes to postural sway parameters compared to control conditions. The novel block instability device used in this investigation may be used similarly to the traditional foam pad in prevention and rehabilitation settings based on the absence of differences between the two devices.

Psychosocial factors associated with lower extremity re-injury risk in soccer players: Contribution of self- confidence, functional attention, and re-injury anxiety.

Despite the availability of specialized assessment tools, psychological readiness is usually not considered when deciding to return to sport (RTS) after sport injury. Re-injury anxiety, self-confidence, and functional attention may be associated with sport re-injury, making it important to evaluate these factors before RTS. This study aimed to predict lower extremity re-injury in soccer players using self- confidence, functional attention, and re-injury anxiety as predictive variables. Prospective cohort study. Laboratory. Sixty-two male soccer players, who were older than 18 years of age, suffered from lower extremity injuries, had completed the rehabilitation program, and were ready to RTS. Prior to returning to the sport, participants completed a pre-season questionnaire on their previous injuries, self-confidence, re-injury anxiety, and level of functional attention. The primary outcome measured was the risk of re-injury during the upcoming competitive season, and logistic regression was utilized to calculate odds ratios (OR) with 95% confidence intervals to determine the association between each risk factor and re- injury. Overall re-injury rate was 5.56 injuries per 1000 hours of play. Self-confidence scores ≤ 47 increased the risk of re-injury by 2.26 times (relative risk, 2.26; 95% CI, 1.31-3.91; OR, 5.00; 95% CI, 1.56-16.04) and each unit increase in self-confidence score reduced the risk of re-injury by 10% (OR:0.90; CI: 0.82-0.99, p=0.03). Regarding re-injury anxiety, a score >22 was associated with 2.43 times the risk of re-injury (relative risk, 2.43; 95% CI, 1.44-4.13; OR, 6.46; 95% CI, 1.93-21.69) and each unit increase in re-injury anxiety score increased the risk of injury by 45% (OR:1.45; CI: 1.13-0.87, p=0.004). Increased re-injury anxiety and decreased self-confidence are associated with higher odds of lower extremity re-injury in male soccer players. To reduce the risk of re-injury, athletic trainers and sport psychologists should take these psychological factors into account when evaluating the psychological readiness of soccer players with a history of lower extremity injury to RTS.

A retrospective comparison of the biceps femoris long head muscle structure in athletes with and without hamstring strain injury history.

Hamstring strain injuries (HSI) and re-injuries are endemic in high-speed running sports. The biceps femoris long head (BFlh) is the most frequently injured muscle among the hamstrings. Structural parameters of the hamstring muscle are stated to be susceptible to strain injuries at this location. This retrospective study targeted comparing the BFlh's structural parameters between previously injured and uninjured athletes. Nineteen male athletes with previous BFlh strain injury history and nineteen athletes without former lower extremity injury history were included in this study. Fascicle length, mid-muscle belly and distal musculotendinous (MTJ) passive stiffnesses of the biceps femoris long head (BFlh) were examined via b-mode panoramic ultrasound scanning and ultrasound-based shear-wave elastography. Parameter comparisons of both legs within and between athletes with and without injury history were performed. Comparison of the BFlh fascicle length between the injured leg of the injured group and the legs of the controls revealed a trend to shorter fascicle lengths in the injured leg (p = 0.067, d = -0.62). However, the mid-muscle belly passive stiffness of the BFlh was significantly higher in the injured legs (p = 0.009, d = 0.7) compared with the controls. Additionally, the distal MTJ stiffness was much higher in the previously injured legs compared with controls (p < 0.001, d = 1.6). Outcomes support the importance of BFlh properties related to stiffness, and fascicle length for injury susceptibility in athletes. Future prospective studies should determine whether the higher stiffness in the injured athletes is a cause or consequence of the HSI. Physical therapy and rehabilitation programmes after HSI should focus on BFlh muscle properties i.e., elasticity and fascicle length for reducing re-injury and increasing sports performance.

Validity Test of Hamstring Muscle Strength Test for Handball Athletes

The purpose of this study was to test the validity of hamstring muscle strength of handball athletes. A total of 30 handball athletes with categories of 15 male athletes (18.0 ± 5.1 years, weight 62.6 ± 20.7 kg, height 173.6 ± 5.0 cm, BMI 22.1 ± 4.0 kg / m2) and female (18.0 ± 5.1 years, weight 54.6 ± 17.4 kg, height 164.7 ± 6.9 cm, BMI 21.4 ± 2.2 kg/m2). No history of lower extremity injuries participated in a hamstring strength test. Hamstring strength tests are performed isometrically with ISO Prone and ISO 60 tests using nordbord tools and load cells tied using hooks called pabletest. From the test results there is a validity level of 0.000 with reliability of 0.8, so that the data can be said to be valid on both tests, namely ISO Prone and ISO 60. Load cells on pabletes are able to measure hamstring muscle strength in handball athletes. The advantages of load cells on pabletes can be made simply but not everyone can make arrangements so as to output data that can be interpreted. Subsequent research can be done using different contractions such as eccentrics and increasing the number of research subjects more by developing better software. Keywords: validity, hamstring, muscle, strength, isometric

Demographic Characteristics and Their Association with Instantaneous Lower Extremity Injury Occurrence in a Division I Athletic Population.

Temporal prediction of lower extremity (LE) injury risk will benefit clinicians by allowing them to better leverage limited resources and target athletes most at risk. To characterize instantaneous risk of LE injury by demographic factors sex, sport, body mass index (BMI), and previous injury history. Instantaneous injury risk was defined as injury risk at any given point in time following baseline measurement. Descriptive epidemiology study. NCAA Division I athletic program. 278 NCAA Division I varsity student-athletes (119 males, 159 females). LE injuries were tracked for 237±235 days. Sex-stratified univariate Cox regression models investigated the association between time to first LE injury and BMI, sport, and previous LE injury history. Relative risk ratios and Kaplan-Meier curves were generated. Variables identified in the univariate analysis were included in a multivariate Cox regression model. Females displayed similar instantaneous LE injury risk compared to males (HR=1.29, 95%CI=[0.91,1.83], p=0.16). Overweight athletes (BMI>25 kg/m2) had similar instantaneous LE injury risk compared with athletes with BMI<25 kg/m2 (HR=1.23, 95%CI=[0.84,1.82], p=0.29). Athletes with previous LE injuries were not more likely to sustain subsequent LE injury than athletes with no previous injury (HR=1.09, 95%CI=[0.76,1.54], p=0.64). Basketball (HR=3.12, 95%CI=[1.51,6.44], p=0.002) and soccer (HR=2.78, 95%CI=[1.46,5.31], p=0.002) athletes had higher risk of LE injury than cross-country athletes. In the multivariate model, females were at greater LE injury risk than males (HR=1.55, 95%CI=[1.00,2.39], p=0.05), and males with BMI>25 kg/m2 were at greater risk than all other athletes (HR=0.44, 95%CI=[0.19,1.00], p=0.05). In a collegiate athletic population, previous LE injury history was not a significant contributor to risk of future LE injury, while being female or being male with BMI>25 kg/m2 resulted in increased risk of LE injury. Clinicians can use these data to extrapolate LE injury risk occurrence to specific populations.

Relationship Between Sensory Organization Testing Scores With Lower Extremity Injuries and Prior Concussion in Professional Soccer Players.

To evaluate for associations between concussion history or lower extremity (LE) injury and computerized sensory organization testing (SOT) performance in professional soccer players. Cross-sectional study. Tertiary care center. Thirty-three, professional, male soccer players on an American club, between the years 2019 and 2021. Player age, history of reported LE injury (gluteal, hamstring, ankle, knee, hip, groin, and sports hernia), history of diagnosed concussion, and the number of prior concussions were documented for each player. Baseline SOT of postural sway was conducted in 6 sensory conditions for all players. Eleven athletes (33%) reported a previous concussion, and 15 (45%) reported a previous LE injury. There were no significant differences in SOT scores between those with and without a previous diagnosis of concussion ( P > 0.05). Those reporting a previous LE injury performed better on condition 3 (eyes open, unstable visual surround) than those who did not ( P = 0.03). Athletes aged 25 years or younger performed worse on condition 3 ( P = 0.01) and had worse, although not statistically significant, median performance on all other balance measures than those older than 25 years. Intraclass correlation coefficient for repeat SOT assessment was 0.58, indicating moderate reliability, without an evident practice effect. Professional soccer players with a previous concussion or history of LE injury did not demonstrate long-term deficits in postural control, as assessed by multiyear computerized SOT baseline testing. The SOT was reliable over time with younger athletes exhibiting greater postural sway than older athletes.

The Effect of Tai Chi on Dynamic Balance in Younger Adults: Implication for Physical Therapy Practice

Purpose: The objective of this study was to investigate the effect of Tai Chi on the dynamic balance in younger, active community-based adults with no history of lower extremity injury or balance problems. Methods: Fourteen subjects (4 males / 10 females; age 23.6 + 6.2 years-old; height 166.5 ± 11.1 cm; weight 75.9 ± 19.3 kg) completed a 13-week undergraduate Tai Chi course. Dynamic balance was assessed at the beginning and the end of the course using the Y-Balance test. Results: Post-hoc testing showed significant improvements in anterior (P=0.007) and posterior lateral (P=0.003) reach distances with a Cohen’s d at 0.54 and 0.71 for the anterior and posterior lateral, respectively with significant improvement in right composite compared to left composite (P&lt;0.0001). Cohen’s d was 0.51 and 1.38 for the left and right composite score, respectively. Conclusions: These findings suggest that Tai Chi may be useful as an exercise regimen to increase anterior and posterior lateral dynamic balance in balance-dependent activity as measured by the Y Balance Test. The authors champion that Tai Chi may be a useful addition for a physical therapy treatment plan, preventative exercise plan, or wellness program to increase anterior and posterior lateral dynamic balance.

Progressive Visual Occlusion and Postural Control Responses in Individuals With and Without Chronic Ankle Instability.

Prophylactic and rehabilitative balance training is needed to maximize postural control and develop appropriate sensory organization strategies. Partially occluding vision during functional exercise may promote appropriate sensory organization strategies, but little is known about the influence of partially occluded vision on postural control in those with and without a history of musculoskeletal injury. To determine the effect of increasing levels of visual occlusion on postural control in a heterogeneous sample of those with and without chronic ankle instability (CAI). The secondary objective was to explore postural control responses to increasing levels of visual occlusion among those with unilateral and bilateral CAI relative to uninjured controls. Cross-sectional. Sports medicine research laboratory. Twenty-five participants with unilateral CAI, 10 with bilateral CAI, and 16 participants with no history of lower extremity injury. All participants completed four 3-minute postural control assessments in double-limb stance under the following 4 visual conditions: (1) eyes open, (2) low occlusion, (3) high occlusion, and (4) eyes closed. Low- and high-occlusion conditions were produced using stroboscopic eyewear. Postural control outcomes included time-to-boundary minima means in the anteroposterior (TTB-AP) and mediolateral directions (TTB-ML). Repeated-measures analysis of variances tested the effects of visual condition on TTB-AP and TTB-ML. Postural control under the eyes-open condition was significantly better (ie,higher) than the limited visual occlusion and eyes-closed conditions (P < .001) for TTB-AP and TTB-ML. For TTB-AP only, partially occluded vision resulted in better postural control than the eyes-closed condition (P ≤ .003). Partial and complete visual occlusion impaired postural control during dual-limb stance in a heterogeneous sample of those with and without CAI. Stroboscopic eyewear appears to induce postural control impairments to the same extent as complete visual occlusion in the mediolateral direction.

Effects of Aerobic and Anaerobic Fatigue Exercises on Postural Control and Recovery Time in Female Soccer Players.

Sixteen female soccer players (age = 20.19 ± 1.52 years; body mass = 56.52 ± 4.95 kg; body height = 164.81 ± 4.21 cm) with no history of lower extremity injury participated in the study. The Biodex SD Balance system was used to determine the non-dominant single-leg stability. In anaerobic exercise, each subject performed four maximal cycling efforts against a resistance equivalent to 0.075 kg/body mass for 30 s with three-minute rest intervals. In aerobic exercise, subjects performed the Bruce protocol on a motorized treadmill. After each exercise, subjects subsequently performed a single-leg stability test and then repeated the same test for four times with five-minute passive rest periods. In accordance with the results, it was found that the impairment observed right after the aerobic loading was higher (p < 0.001) compared to the anaerobic one. However, the time-related deterioration in both aerobic and anaerobic loadings was similar. The B-pre value was lower than Bpost and B5 (p < 0.01) and B10 (p < 0.05) in both conditions. Subjects could reach the initial balance level at B15 after aerobic and anaerobic loadings. The lactate level did not reach resting value even after 20 min of both fatigue protocols. Although the fatigue after aerobic and aerobic exercise negatively affects a single-leg dynamic balance level, single leg balance ability returns to the baseline status after 10 min of passive recovery duration.

Landing Biomechanics in Adolescent Athletes With and Without a History of Sports-Related Concussion.

Recent evidence suggests previously concussed athletes are at greater risk for lower-extremity (LE) injuries than are controls. However, little is known regarding the influence of sports-related concussion (SRC) on landing biomechanics that may provide a mechanistic rationale for LE injury risk. The purpose of this investigation was to examine LE drop-landing biomechanics in adolescent athletes with and without a previous SRC history. Participants included 10 adolescent athletes with an SRC history and 11 controls from multiple sports. Three-dimensional kinematic and kinetic data associated with LE injury risk were analyzed across 5 trials for 30- and 60-cm landing heights. Multivariate analyses indicated group differences in landing patterns from the 30- (P = .041) and 60-cm (P = .015) landing heights. Follow-up analyses indicated that concussed adolescent athletes demonstrated significantly less ankle dorsiflexion and knee flexion versus controls when performing drop landings. Our findings suggest that previously concussed adolescent athletes complete drop-landing maneuvers with ankle and knee joint kinematic patterns that suggest greater risk for LE injury. While limitations such as sport variety and explicit LE injury history are present, the results of this study provide a possible biomechanical rationale for the association between SRC and LE injury risk.

Does Lower Extremity ROM Asymmetry Or Previous Injury Predict Weight Shift During The FMS Squat?

The Functional Movement Screen (FMS) Deep Squat Test (DS) assesses bilateral mobility of the ankle, knee and hip through a movement pattern that is intended to be performed with bilateral symmetry. Past history of lower extremity (LE) injury may influence LE joint range of motion (ROM). Previous studies have examined the influence of LE ROM on squat depth, but not its influence on lateral weight shift (LWS). PURPOSE: The purpose of this study was to determine if bilateral asymmetry in ankle, knee, and hip ROM or previous history of LE injury predicts LWS during the FMS DS. METHODS: Thirty-seven physically active subjects (19 F, 18 M, 20.8 ± 1.4 yrs) completed this IRB approved study. All subjects granted informed consent and completed a health history questionnaire including history of LE orthopedic injury. Subjects’ hip flexion (HF), knee flexion (KF), and ankle dorsiflexion (DF) ROM were measured with a goniometer using standard methodologies. A loaded lunge (LL) measurement was also taken to determine peak closed chain dorsiflexion. ROM asymmetry was calculated for each measurement. Participants then completed three trials of the FMS DS on 2 force plates (1200 Hz) and a Matlab script processed vertical ground reaction force (vGRF) data with a lowpass filter and computed limb symmetry index during the descent phase and full squat position. Multiple regression models were computed for both the descent phase and the full squat position of the DS to determine if ankle, knee, and hip ROM asymmetry, LL asymmetry, and LE injury history are predictors of LWS during the DS. RESULTS: Mean ROM asymmetries for HF (-0.09% ± 3.37), KF (0.24% ± 1.8), DF (-5.30% ± 43.28) and LL (5.14% ± 8.93) were calculated. The overall regression model for the descent phase was not significant, (F(5, 31) = 0.47, p = 0.796, r2 = 0.07) for the prediction of LWS. Additionally, the overall regression model for the full squat position was also not significant (F(5, 31) = 1.67, p = 0.17, r2 = 0.21) for the prediction of LWS. CONCLUSION: Asymmetry in HF, KF, and DF ROM along with LL asymmetry and previous history of LE injury do not predict LWS during FMS DS performance. Further investigation is needed to identify the causes of asymmetric DS performance to aid clinicians in corrective exercise prescription.

무릎 스트랩과 테이핑 적용이 배구선수의 외발 착지에서 슬개건 통증과 하지 동역학 및 운동학에 미치는 영향

The primary purpose of this study was to compare patellar tendon pain and low extremity kinetics and kinematics of male high school volleyball players on one-leg landing after applying a strap, C-tape, and E-tape, respectively. A total of 16 male high school volleyball players who had no history of lower extremity injury at least for 3 months were recruited(age: 16.37±1.08years, height: 185.56±5.52cm, weight: 76.81±8.52kg). Each participant were alternately equipped with a strap, C-tape, or E-tape on each patellar tendon, and visual analogue scale(VAS) was measures during one leg landing. Maximal knee flexion angle, range of motion, angular velocity, moment, and maximal ground reaction force at the hip, knee, and ankle joint were assessed after each application using 3 dimensional motion analyses. Statistical analyses were done with one-way repeated measure ANOVA and post-hoc analysis. The VAS of strap(2.56±1.45) and C-tape(2.87±1.31) were lower than that of E-tape(3.50±1.31; each p.001 and p=.007). The mean angular velocity of the knee flexion (285.77±88.60deg/s) was significantly higher in strap than in E-tape(242.68±61.64deg/s; p=.026). In summary, it appeared that the application of strap or C-tape was related to effectively reducing patellar tendon pain. Additionally, it could be postulated that the application of a strap attributed to the increase of knee flexion angular velocity during one-leg landing.

Reconsidering Reciprocal Length Patterns of the Anteromedial and Posterolateral Bundles of the Anterior Cruciate Ligament During In Vivo Gait

Background: Some cadaveric studies have indicated that the anterior cruciate ligament (ACL) consists of anteromedial and posterolateral bundles that display reciprocal function with regard to knee flexion. However, several in vivo imaging studies have suggested that these bundles elongate in parallel with regard to flexion. Furthermore, the most appropriate description of the functional anatomy of the ACL is still debated, with the ACL being described as consisting of 2 or 3 bundles or as a continuum of fibers. Hypothesis: As long as their origination and termination locations are defined within the ACL attachment site footprints, ACL bundles elongate in parallel with knee extension during gait. Study Design: Descriptive laboratory study. Methods: High-speed biplanar radiographs of the right knee joint were obtained during gait in 6 healthy male participants (mean ± SD: body mass index, 25.5 ± 1.2 kg/m2; age, 29.2 ± 3.8 years) with no history of lower extremity injury or surgery. Three-dimensional models of the right femur, tibia, and ACL attachment sites were created from magnetic resonance images. The bone models were registered to the biplanar radiographs, thereby reproducing the in vivo positions of the knee joint. For each knee position, the distances between the centroids of the ACL attachment sites were used to represent ACL length. The lengths of 1000 virtual bundles were measured for each participant by randomly sampling locations on the attachment site surfaces and measuring the distances between each pair of locations. Spearman rho rank correlations were performed between the virtual bundle lengths and ACL length. Results: The virtual bundle lengths were highly correlated with the length of the ACL, defined as the distance between the centroids of the attachment sites (rho = 0.91 ± 0.1, across participants; P < 5 × 10-5). The lengths of the bundles that originated and terminated in the anterior and medial aspects of the ACL were positively correlated (rho = 0.81 ± 0.1; P < 5 × 10-5) with the lengths of the bundles that originated and terminated in the posterior and lateral aspects of the ACL. Conclusion: As long as their origination and termination points are specified within the footprint of the attachment sites, ACL bundles elongate in parallel as the knee is extended. Clinical Relevance: These data elucidate ACL functional anatomy and may help guide ACL reconstruction techniques.

Daily walking volume and intensity after anterior cruciate ligament reconstruction: a preliminary analysis

Purpose: Lower knee joint loading during walking is associated with markers of adverse cartilage health after anterior cruciate ligament reconstruction (ACLR), suggesting that underloading may play a role in the development of post-traumatic osteoarthritis. However, these magnitude-based measures of loading were determined using laboratory-based gait analyses over a single step, which may not reflect habitual daily walking. Understanding the characteristics of daily walking in individuals after ACLR is a critical first step toward understanding how daily walking affects cartilage health in this population. Thus, the purpose of this preliminary analysis was to examine differences in volume and intensity characteristics of daily walking between individuals early after ACLR, later after ACLR, and uninjured controls. Methods: This cross-sectional study is a secondary analysis of data from three prior studies. We included individuals who were at least 6 months post-ACLR, and divided the sample based on time since ACLR: early (6-12 months post-ACLR; 8.0 ± 1.5 months post-ACLR) and later (>12 months post-ACLR; 61.4 ± 41.9 months post-ACLR). We included individuals without a history of lower extremity injury or surgery as a control group. Daily walking was assessed using a triaxial accelerometer (Actigraph Link) worn at the right hip. Participants were instructed to wear the accelerometer during all waking hours aside from water activities for 7 days. Data were considered valid if the accelerometers was worn for ≥ 10 hours/day for ≥ 4 days. The outcome of interest was daily walking volume (total steps per day), daily walking intensity (steps per day at a moderate-vigorous (MV) intensity), and proportion of total steps accumulated at MV (steps per day at MV/total steps per day expressed as a percentage). MV intensity was defined as walking at ≥ 100 steps per minute. For this preliminary analysis, we calculated effect sizes (Cohen’s d) to evaluate the difference in daily walking between groups (early, late, control). Effect size magnitude was interpreted as no effect (0-0.19), small (0.20-0.49), medium (0.50-0.79) and large (≥0.8). Results: Sixty-two participants (22.5 ± 4.1 years, 48% men, body mass index 24.2 ± 2.8 kg/m2) were included in this analysis (early n=21, later n=19, control n=22; Table 1). Compared to the later group post-ACLR, the early group accumulated fewer total steps per day (large effect, Table 2), fewer steps at MV (medium effect), and a lower proportion of steps at MV (small effect). Compared to the control group, the early group accumulated similar total steps per day, yet fewer steps at MV (small effect) and a lower proportion of steps at MV (medium effect). Compared to the control group, the later group accumulated more total steps per day (medium effect), yet similar steps at MV and a lower proportion of steps at MV (small effect).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Conclusions: This preliminary analysis suggests that individuals early after ACLR accumulate fewer total steps per day and fewer steps at MV compared to individuals late after ACLR and fewer steps at MV compared to healthy controls. Interestingly, individuals late after ACLR accumulate a lower proportion of daily steps at MV compared to healthy peers, despite walking more total steps. This analysis was limited to description of effect sizes due to small sample sizes and should be interpreted accordingly. Further studies in larger samples are warranted to understand daily walking recovery after ACLR and the extent to which it relates to measures of joint health.

Elit Atletlerde Alt Ekstremite Yaralanma Öyküsü: Kinezyofobi ile İlişkisi ve Fiziksel Performans Üzerindeki Etkisi

Objective: Considering the psychosocial factors of performance, the injury history will affect the physical performance parameters. Kinesiophobia is one of these factors. Although injuries are effective with motivation factors in athletes, the focus of research is on physical factors. Accordingly the main objective of the study was to investigate the presence of kinesiophobia in elite athletes with and without a history of lower limb injury. The secondary aim was to determine the relationship between physical performance and, kinesiophobia in elite athletes. Material and Methods: The presence of a history of lower extremity injury was questioned in athletes and the time was recorded. The fear of movement was evaluated using the Tampa Scale of Kinesiophobia (TSK-17). Performance evaluations of athletes were carried out under the titles of flexibility, balance, anaerobic and aerobic tests. Obtained data were analyzed by appropriate statistical methods. Results: Kinesiophobia level was different between athletes with and without a history of lower limb injuries (95%CI: 35.06 [33.41 to 36.71], p: 0.016). The athletes with lower limb injury history have higher kinesiophobia than athletes without lower limb injury history (p<0.05). There was a correlation between the kinesiophobia and, the history of lower limb injury of the athletes (r:0.350, p:0.015). No correlation was found in any subtitle of the physical performance tests and the history of lower limb injury (p>0.05). Conclusion: According to our study results the athletes with lower limb injury history have higher kinesiophobia than athletes without lower limb injury history. Kinesiophobia was related with lower limb injury history and not related with physical performance.

Body Composition Characteristics and Knee Injury Prevalence of NCAA Division I Women's Soccer and Lacrosse

Body composition is directly linked to athletic performance and may influence injury risk and recovery. Female Division I soccer and lacrosse players are at a high risk for lower limb injuries specific to the knee joint throughout their competitive careers. Return to play criterion vary; evaluation of body composition may be an important element of clearance. PURPOSE: The purpose of this study was to characterize pre-season body composition and injury prevalence among female Division I soccer and lacrosse players using dual-energy x-ray absorptiometry (DEXA). METHODS: Sixty Division I Women’s Soccer (n=27) and Lacrosse (n=33) athletes (Mean ± SD: age:19.8 ± 1.4 yrs, height, 167.3 ± 6.2 cm, weight, 64.9 ± 8.0 kg,) completed a whole body DEXA scan to determine fat mass (FM), percent body fat (%fat), lean mass (LM), segmental lean mass [right leg lean mass (RLM); left leg lean mass (LLM)], and bone mineral content (BMC). History of lower extremity injury (ACL and other knee injuries) throughout a career was self-reported using a validated questionnaire. Measurements were taken pre-season (August 2018). RESULTS: Soccer and lacrosse players combined (n=60) demonstrated the following body composition characteristics: total body FM (15.23 ± 4.8 kg), total body LM (46.96 ± 4.7 kg), and BMC (2.78 ±0 .3). There were significant differences between sports in %fat and segmental LM (LLM and RLM). Lacrosse athletes had higher %fat compared to soccer athletes: (mean difference [MD] ± SD: 2.5 ± 2.3%; p=0.034). Segmental leg LM (LLM, RLM) was higher in both legs of soccer athletes (LLM MD: 0.08 ± 0.54kg; p=0.004, RLM MD: 0.89 ± 5.2kg; p=0.001). In the full sample, there was no significant difference (p=0.139) between RLM and LLM. When evaluating injured vs. not injured athletes in the full sample, 45% of athletes reported a knee injury; %fat was significantly higher for athletes with no injury history (MD: 2.5±2.4%; p=0.046). CONCLUSIONS: These finding suggest that Division I soccer and lacrosse players who have returned to play following a lower extremity injury do not experience differences in segmental leg lean mass between the left and right leg. Based on the elite level of these teams, these data could portray optimal characteristics of successful athletes returned to play.

Biomechanical and Functional Outcomes After Medial Patellofemoral Ligament Reconstruction: A Pilot Study

Background:Previous studies have acknowledged the medial patellofemoral ligament (MPFL) as the primary stabilizer of the patella, preventing lateral displacement. MPFL reconstruction (MPFL-R) restores stability and functionality to the patellofemoral joint and has emerged as a preferred treatment option for recurrent lateral patellar instability.Purpose:To objectively measure biomechanical characteristics of athletes cleared for return to sport after MPFL-R compared with healthy controls.Study Design:Cohort study; Level of evidence, 3.Methods:A prospective case-control study design was employed on 31 total athletes. Sixteen athletes (6 male, 10 female; mean age, 16.1 ± 2.74 years; 385 ± 189 days after surgery and 235 ± 157 days after return to sport) underwent MPFL-R and were medically cleared to return to sport. This group was matched by age, sex, and activity level to 15 healthy athletes with no history of lower extremity injuries. Athletes and controls completed validated questionnaires as well as hopping, jumping, and cutting tests with 3-dimensional motion analysis and underwent strength, flexibility, laxity, and balance assessments.Results:Participants in the MPFL-R group scored significantly lower (worse) on the International Knee Documentation Committee (IKDC) (89.2 ± 7.6 vs 98.1 ± 2.0, respectively; P = .0005) and significantly higher (worse) on the Tampa Scale for Kinesiophobia (TSK) (32.4 ± 5.0 vs 25.4 ± 6.5, respectively; P = .006) than those in the control group, but there was no difference in the Kujala score (95.6 ± 5.3 vs 98.8 ± 3.0, respectively; P = .06). Participants in the MPFL-R group demonstrated reduced hip and ankle flexion relative to those in the control group (P < .05). Participants in the MPFL-R group also took significantly longer to complete the 6-m timed hop test relative to those in the control group (P < .05). No statistically significant differences were found in anthropometrics, knee extension or flexion strength, hamstring flexibility, hip abduction strength, or joint laxity between the MPFL-R and control groups.Conclusion:The current data indicate that MPFL-R generally restores functional symmetry, while subtle deficits in global power may remain after being released to full activity. Clinicians should ensure that athletes are fully rehabilitated before returning to sport after MPFL-R by emphasizing functional multijoint exercises.

高校サッカー選手の下肢傷害既往とFunctional Movement Screenの関連

高校サッカー選手の下肢傷害既往とFunctional Movement Screenの関連

Association between double-leg squat and single-leg squat performance and injury incidence among incoming NCAA Division I athletes: A prospective cohort study

ObjectivesDetermine the association between performance on the double-leg squat (DLS) and single-leg squat (SLS) and prospective injury incidence in athletes. DesignProspective cohort study. SettingNational Collegiate Athletic Association (NCAA) Division I university. Participants111 incoming NCAA Division I athletes from 10 varsity sports teams. Main outcome measuresPerformance on the DLS and SLS were assessed as “poor” or “non-poor.” Lower extremity (LE) injury data for the following year were extracted from electronic medical records. Multivariate Poisson regression was used to compare the incidence of LE injuries in athletes with poor versus non-poor performance on the DLS and SLS. ResultsThe final models for the DLS and SLS were adjusted for sex and LE injury history and yielded an incidence rate ratio (IRR) of 1.33 (95% CI: 0.80 2.22) for the DLS and 1.62 (95% CI: 0.98, 2.66) for the SLS when comparing poor to non-poor movers. ConclusionsAthletes with poor LE movement quality assessed on the DLS or SLS had greater incidence of LE injury than those with non-poor movement quality. This is the first study to demonstrate an association between performance on the double-leg squat and single-leg squat and injury risk in NCAA athletes.