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Background: With grade 3 posterolateral injuries of the knee, reconstructions of the lateral collateral ligament, popliteus tendon, and popliteofibular ligament are commonly performed in conjunction with a posterior cruciate ligament [...]

Underloading the surgical limb has been described in biomechanical studies across recovery time points following anterior cruciate ligament reconstruction (ACLr). This study aimed to examine the extent to which laboratory findings translate to daily activities. Limb loading was quantified during a sit‐to‐stand task in laboratory testing and throughout 2 days of daily activity in 15 individuals 114.8 (17.2) days post‐ACLr and 15 controls. Vertical force impulse calculated from force platform (laboratory) and pressure insoles (daily) was used to quantify limb loading. Between‐limb symmetry was calculated for limb loading and knee strength measures, 2 × 2 GLM repeated measures determined a significant group‐by‐limb interaction on daily limb loading. Surgical limb daily loading was lower compared to nonsurgical (p <.001; effect sizes [ES] = 0.63), and control matched limbs (surgical: p =.037, ES = 0.80 and nonsurgical: p =.02, ES = 0.89). No group differences were found in total daily loading (summed loading between limbs; p =.18; ES = 0.50) and time performing weight‐bearing activities (p =.32; ES = 0.36). Pearson's correlation determined that between‐limb symmetry in daily loading was related to sit‐to‐stand loading (r =.62; p =.01) and knee extensor strength symmetry (r =.6; p =.02) in the ACLr group. These data support the presence of underloading behaviors in individuals 10–14 weeks following ACLr that are consistent with previous biomechanical studies and current biomechanical data. Knee extensor weakness was related to greater underloading. Asymmetrical loading quantified in the laboratory is practiced throughout the day in individuals post‐ACLr. Practice afforded by daily activities represents powerful contributors to learning of a pattern that contrasts the goal of rehabilitation exercises. [ABSTRACT FROM AUTHOR]

Knee injuries are common in jumping athletes; modifying jump strategy may impact loads placed on the body and reduce injury risk. The purpose of this study was to determine if modifying strategy in a saut de chat leap to focus on height would decrease sagittal plane knee loading. Biomechanical data were collected while 28 dancers performed saut de chat leaps with instructions to jump far (FAR) or jump high (UP). In the UP condition, there was greater vertical GRF and less braking GRF. Also in UP, lower extremity contact angle was greater (71.3 ± 2.9º FAR; 75.8 ± 3.3º UP; p = 0.0178), peak knee extensor moment was greater (2.8 ± 0.7 Nm FAR; 3.2 ± 0.8 Nm UP; p = 0.01), and peak ankle plantar flexor moment was lower (3.19 ± 0.4 Nm FAR; 2.94 ± 0.4 Nm UP; p < 0.01). A more acute LECA was related to greater braking force and braking force was related to greater knee extensor moments. Despite these relationships, we observed greater knee extensor moments in UP. While the relationship among these whole-body variables and knee joint loading exists, it may not be the primary factor driving load distribution during dance leap landings. [ABSTRACT FROM AUTHOR]

Biomechanical studies consistently report smaller knee extensor moments in the surgical limb during loading response (LR) of gait following ACL reconstruction (ACLr). However, this reduction in knee loading is quantified by net joint moments (NJM). As a result, in the presence of greater hamstring activity, the true contribution from the knee extensors may not be reduced. The purpose of this study is to compare hamstring activity and strength and knee joint moments between individuals post‐ACLr and controls. Eighteen individuals 3 months post‐ACLr and matched controls walked and net knee extensor moment peak and impulse and hamstring activity were identified during LR, as well as maximal hamstring strength. A hybrid musculoskeletal model estimated knee flexor moments from joint kinematics and hamstring electromyography. Flexor moments (SIMM) were scaled based on strength. Knee extensor moments were estimated from the sum of the net knee moment and estimated knee flexor moment; estimated extensor moment peaks and impulse were calculated during LR. Repeated measures analysis of variance compared groups and limbs. Smaller net knee extensor moment and greater hamstring activity, as well as deficits in maximal hamstring strength, were observed in the surgical limb (all p < 0.05). When accounting for the torque‐producing capabilities of the knee flexors, estimated knee extensor moment peak and impulse were smaller in the surgical limb. These findings suggest that net knee moments accurately reflect smaller knee extensor loading post‐ACLr. Statement of Clinical Significance: Rehabilitation programs should target increasing knee extensor loading to restore gait mechanics during early rehabilitation. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:378‐386, 2020 [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effects of practice on performance of a running task requiring maximal speed and accurate termination. Physically active pre-pubertal boys and men ran as fast as possible and stopped at a pre-determined target location. Twenty-five trials were collected and comparisons made between first five (early) and last five (late) trials. Approach velocity, normalized approach velocity (percent of maximal sprint velocity, %Vmax), stopping distance from target, and success rate were calculated. Self-efficacy for task performance and fatigue reports were collected prior to trials. Children ran more slowly than adults in absolute terms but performed at higher relative velocity. Both groups displayed similar accuracy and percentages of successful trials across early and late practice. Adults increased approach velocity and %Vmax from early to late; children, already higher in relative maximal velocity, did not change. Self-efficacy paralleled performance findings and correlated with %Vmax and success rate; both groups reported higher self-efficacy for late compared with early. With practice, adults increased approach velocity and children did not; however, children appeared to be performing at a higher relative level from the beginning, perhaps reflecting their more substantial recent histories of similar physical activity and limiting further effects of practice. [ABSTRACT FROM AUTHOR]

Background: Clinically, normalization of gait following anterior cruciate ligament reconstruction (ACLr) is defined as the absence of observable deviations. However, biomechanical studies report altered knee mechanics during loading response (LR); a time of double limb support and weight transfer between limbs. It is conceivable that subtle adjustments in whole body mechanics, including center of mass (COM) velocity and ground reaction force (GRF) peaks and timing, are present.Research Question: The purpose was to compare limb and whole body mechanics during LR of gait in the surgical and non-surgical limbs post-ACLr.Methods: Anterior and vertical COM velocity at initial contact; knee flexion range of motion, peak knee extensor moment, peak vertical and posterior GRF, minimum vertical COM position and maximum anterior and vertical COM velocity during LR were identified for twenty individuals 112 ± 17 days post-ACLr without observable gait deficits. To assess differences in timing of COM variables, coupling angles (vector coding) were calculated for multidirectional coordination of vertical and anteroposterior COM velocities and GRFs and categorized as in-phase, anti-phase, vertical phase, or anteroposterior phase coordination. Paired t-tests compared peaks between limbs; non-parametric Wilcoxon signed-rank tests compared coordination pattern frequency.Results: Less knee range of motion (5.6 °), 30% smaller knee extensor moment, 11% smaller posterior GRF, and slower anterior COM velocity at initial contact (2%) and peak during LR (1.3%; all p < 0.05) were observed in the surgical compared to the non-surgical limb. For COM velocity coordination, lesser anti-phase (7.38%) and greater in-phase coordination (2.88%) were observed in the surgical limb. For GRF coordination, less in-phase coordination (1.94%) was observed in the surgical limb.Significance: Differences in coordination patterns, suggest that individuals post-ACLr make subtle adjustments in timing of whole body mechanics; particularly in COM velocity during gait. These adjustments are consistent with reduced sagittal plane loading in the surgical knee. [ABSTRACT FROM AUTHOR]

BACKGROUND: Following anterior cruciate ligament reconstruction (ACLR), individuals present with significant knee power absorption deficits during deceleration of dynamic tasks. An inability to quantify these deficits clinically may underlie their persistence. Recent studies suggest that segment angular velocities measured with wearable inertial sensors have the potential to provide valuable information about knee power during a single-limb loading (SLL) task. However, the diagnostic accuracy of these measures and procedures needs to be established before translating this information to clinical practice. OBJECTIVE: To determine the diagnostic accuracy of using inertial-sensor thigh angular velocities to detect asymmetrical knee loading during a dynamic SLL task in individuals following ACLR. METHODS: In this controlled laboratory study, 21 individuals following ACLR performed 3 trials of SLL on each limb. Sagittal plane peak knee power absorption was calculated for each limb (reconstructed and nonsurgical) during deceleration. Between-limb ratios (reconstructed/nonsurgical limb) were calculated for knee power using marker-based motion analysis, and thigh angular velocity was extracted from inertial sensors. Sensitivity and specificity of thigh angular velocity ratios in diagnosing asymmetrical knee loading (knee power deficits greater than 15%) were determined using receiver operating characteristic curve analysis. RESULTS: Thigh angular velocity ratios detected asymmetrical knee loading when performing SLL with high sensitivity (81%) and specificity (100%). CONCLUSION: These findings support the use of cost-effective wearable sensors to objectively quantify movement clinically in this population of individuals following ACLR. This study establishes procedures for the clinical quantification of dynamic knee loading deficits. [ABSTRACT FROM AUTHOR]

BACKGROUND: Decreased extensor moments in the surgical knee during bilateral squats can persist beyond 1 year following anterior cruciate ligament reconstruction (ACLR). This is accomplished using interlimb and intralimb compensations. OBJECTIVES: This study sought to assess loading during squatting longitudinally, 3 and 5 months post ACLR, and to determine the extent to which interlimb and intralimb compensations contribute to reduced knee extensor moments. METHODS: In this controlled, longitudinal laboratory study, 11 individuals (4 male) underwent 3-D motion analysis of a squat at 3 and 5 months post ACLR. A repeated-measures multivariate analysis of variance (limb by time) assessed differences in peak knee and hip flexion angles, knee extensor moment, vertical ground reaction force, and hip-to-knee extensor moment ratio. Stepwise linear regression analysis was used to determine the contribution of interlimb (between-limb vertical ground reaction force ratio) and intralimb (within-surgical-limb hip-to-knee moment ratio) compensations to the between-limb knee extensor moment ratio. RESULTS: A significant effect of limb was observed for knee flexion angle, knee extensor moment, vertical ground reaction force, and hip-to-knee extensor moment ratio, while a significant effect of time was observed for knee extensor moment and hip-to-knee extensor moment ratio. At 3 months, the vertical ground reaction force ratio and hip-to-knee extensor moment ratio predicted the knee extensor moment ratio (R² = 0.854, P<.001). At 5 months, the hip-to-knee extensor moment ratio predicted the knee extensor moment ratio (R² = 0.584, P = .006). U UCONCLUSION: Individuals used interlimb and intralimb compensations to reduce the knee extensor moment of the surgical limb at 3 months post ACLR. Similar reductions in the knee extensor moment at 5 months were accomplished with only intralimb compensations. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effects of practice on performance of a running task requiring maximal speed and accurate termination. Physically active pre-pubertal boys and men ran as fast as possible and stopped at a pre-determined target location. Twenty-five trials were collected and comparisons made between first five (early) and last five (late) trials. Approach velocity, normalized approach velocity (percent of maximal sprint velocity, %Vmax), stopping distance from target, and success rate were calculated. Self-efficacy for task performance and fatigue reports were collected prior to trials. Children ran more slowly than adults in absolute terms but performed at higher relative velocity. Both groups displayed similar accuracy and percentages of successful trials across early and late practice. Adults increased approach velocity and %Vmax from early to late; children, already higher in relative maximal velocity, did not change. Self-efficacy paralleled performance findings and correlated with %Vmax and success rate; both groups reported higher self-efficacy for late compared with early. With practice, adults increased approach velocity and children did not; however, children appeared to be performing at a higher relative level from the beginning, perhaps reflecting their more substantial recent histories of similar physical activity and limiting further effects of practice. [ABSTRACT FROM AUTHOR]

Objective: To provide certified athletic trainers, physicians, and other health care and fitness professionals with recommendations based on current evidence regarding the prevention of noncontact and indirect-contact anterior cruciate ligament (ACL) injuries in athletes and physically active individuals. Background: Preventing ACL injuries during sport and physical activity may dramatically decrease medical costs and long-term disability. Implementing ACL injury-prevention training programs may improve an individual's neuromuscular control and lower extremity biomechanics and thereby reduce the risk of injury. Recent evidence indicates that ACL injuries may be prevented through the use of multicomponent neuromusculartraining programs. Recommendations: Multicomponent injury-prevention training programs are recommended for reducing noncontact and indirect-contact ACL injuries and strongly recommended for reducing noncontact and indirect-contact knee injuries during physical activity. These programs are advocated for improving balance, lower extremity biomechanics, muscle activation, functional performance, strength, and power, as well as decreasing landing impact forces. A multicomponent injury-prevention training program should, at minimum, provide feedback on movement technique in at least 3 of the following exercise categories: strength, plyometrics, agility, balance, and flexibility. Further guidance on training dosage, intensity, and implementation recommendations is offered in this statement. [ABSTRACT FROM AUTHOR]

* STUDY DESIGN: Controlled laboratory study, cross-sectional. * BACKGROUND: Well-documented deficits in sagittal plane knee loading during dynamic tasks indicate that individuals limit the magnitude of knee loading following anterior cruciate ligament reconstruction (ACLR). It is unknown how these individuals modulate the speed of knee flexion during loading, which is particularly important as they progress to running during rehabilitation. * OBJECTIVE: To investigate how individuals following ACLR perform dynamic knee loading tasks compared to healthy controls. * METHODS: Two groups of recreationally active individuals participated: 15 healthy controls and 15 individuals post-ACLR (ACLR group). Participants performed 3 trials of overground running and a single-limb loading (SLL) task. Sagittal plane range of motion, peak knee extensor moment, peak knee flexion angular velocity, peak knee power absorption, and rate of knee extensor moment were calculated during deceleration. A mixed-factor multivariate analysis of variance was performed to compare differences in variables between groups (ACLR and control), limbs (within ACLR), and tasks (within control). * RESULTS: Knee power absorption, knee flexion angular velocity, and rate of knee extensor moment were lower in reconstructed limbs (for the SLL task: 5.6 W/kg, 325.87s, and 10.5 Nm/kg/s, respectively; for running: 11.8 W/kg, 421.4°s, and 38.2 Nm/kg/s, respectively) compared to nonsurgical limbs (for the SLL task: 9.7 W/kg, 432.0°/s, and 19.1 Nm/kg/s, respectively; for running: 18.8 W/kg, 494.1°/s, and 72.8 Nm/kg/s, respectively) during both tasks (P<.001). The magnitudes of between-limb differences in knee flexion angular velocity were similar in both tasks. * CONCLUSION: Despite lower loading demands during SLL, individuals post-ACLR exhibit deficits in knee dynamics during SLL and running, suggesting an inability or reluctance to dynamically accommodate forces at the knee when progressing to running in rehabilitation. [ABSTRACT FROM AUTHOR]

Limitations in the ability to identify knee extensor loading deficits during gait in individuals following anterior cruciate ligament reconstruction (ACLr) may underlie their persistence. A recent study suggested that shank angular velocity, directly output from inertial sensors, differed during gait between individuals post-ACLr and controls. However, it is not clear if this kinematic variable relates to knee moments calculated using joint kinematics and ground reaction forces. Heel rocker mechanics during loading response of gait, characterized by rapid shank rotation, require knee extensor control. Measures of shank angular velocity may be reflective of knee moments. This study investigated the relationship between shank angular velocity and knee extensor moment during gait in individuals (n=19) 96.7±16.8days post-ACLr. Gait was assessed concurrently using inertial sensors and a marker-based motion system with force platforms. Peak shank angular velocity and knee extensor moment were strongly correlated (r=0.75, p<0.001) and between limb ratios of angular velocity predicted between limb ratios of extensor moment (r(2)=0.57, p<0.001) in the absence of between limb differences in spatiotemporal gait parameters. The strength of these relationships indicate that shank kinematic data offer meaningful information regarding knee loading and provide a potential alternative to full motion analysis systems for identification of altered knee loading following ACLr. [ABSTRACT FROM AUTHOR]

For young adults, balance is essential for participation in physical activities but is often disrupted following lower extremity injury. Clinical outcome measures such as single limb balance (SLB), Y-balance (YBT), and the single limb hop and balance (SLHB) tests are commonly used to quantify balance ability following injury. Given the varying demands across tasks, it is likely that such outcome measures provide useful, although task-specific, information. But the extent to which they are independent and contribute to understanding the multiple contributors to balance is not clear. Therefore, the purpose of this study was to investigate the associations among these measures as they relate to the different contributors to balance. Thirty-seven recreationally active young adults completed measures including Vertical Jump, YBT, SLB, SLHB, and the new Lower Extremity Dexterity test. Principal components analysis revealed that these outcome measures could be thought of as quantifying the strength, multijoint coordination, and sensorimotor processing contributors to balance. Our results challenge the practice of using a single outcome measure to quantify the naturally multidimensional mechanisms for everyday functions such as balance. This multidimensional approach to, and interpretation of, multiple contributors to balance may lead to more effective, specialized training and rehabilitation regimens. [ABSTRACT FROM AUTHOR]

Objective: To compare frontal plane knee moments, and kinematics and kinetics associated with knee valgus moments between cutting to 45 and 110 degrees, and to determine the predictive value of kinematics and ground reaction forces (GRFs) on knee valgus moments when cutting to these angles. Also, to determine whether sex differences exist in kinematics and kinetics when cutting to 45 and 110 degrees. Design: Cross-sectional study. Setting: Laboratory setting. Participants: Forty-five (20 females) healthy young adult soccer athletes aged 16 to 23 years. Assessment of Risk Factors: Kinematic and kinetic variables were compared between randomly cued side-step cutting maneuvers to 45 and 110 degrees. Predictors of knee valgus moment were determined for each task. Main Outcome Measures: Kinematic variables: knee valgus angle, hip abduction, and internal rotation angles. Kinetic variables: vertical, posterior, and lateral GRFs, and knee valgus moment. Results: Knee valgus moments were greater when cutting to 110 degrees compared with 45 degrees, and females exhibited greater moments than males. Vertical and lateral GRFs, hip internal rotation angle, and knee valgus angle explained 63% of the variance in knee valgus moment during cutting to 45 degrees. During cutting to 110 degrees, posterior GRF, hip internal rotation angle, and knee valgus angle explained 41% of the variance in knee valgus moment. Conclusions: Cutting tasks with larger redirection demands result in greater knee valgus moments. Similar factors, including shear GRFs, hip internal rotation, and knee valgus position contribute to knee valgus loading during cuts performed to smaller (45 degrees) and larger (110 degrees) angles. Clinical Relevance: Reducing vertical and shear GRFs during cutting maneuvers may reduce knee valgus moments and thereby potentially reduce risk for anterior cruciate ligament injury. [ABSTRACT FROM AUTHOR]

Quick changes of direction during running (cutting) represent a whole body mechanical challenge, as they require deceleration and translation of the body during ongoing movement. While much is known with respect to whole body demands during walking turns, whole body mechanics and anticipatory adjustments necessary for cutting are unclear. As the ability to rapidly change direction is critical to athletes' success in many sports, a better understanding of whole body adjustments made during cuts is needed. Whole body center of mass velocity and position during the approach and execution steps of three tasks (straight running, 45° sidestep cut, and 90° sidestep cut) performed as fast as possible were compared in 25 healthy soccer athletes. Repeated measure ANOVA revealed that overall, braking and translation were greater during the cuts compared to the straight run. Interestingly, with systematically increased cut angle, disproportionately greater braking but proportionately greater translation was observed. Anticipatory adjustments made prior to the execution of the cuts suggested that individuals evenly distributed the deceleration and redirection demands across steps of the 45° cut but prioritized deceleration over translation during the approach step of the 90° cut. [ABSTRACT FROM AUTHOR]

Cutting is necessary for participation in multidirectional sports but is also associated with non-contact ACL injury. Whole body demands of deceleration and redirection increase with greater cut angles. However, it is not known how these demands relate to differences in joint and segmental mechanics. Understanding the relationship between whole body and joint mechanics necessary for cutting and those related to risk for injury is important for the development of injury prevention training programs. The purpose of this study is to determine how joint and segmental mechanics change to meet increasing deceleration and redirection demands during cutting. Lower limb and trunk kinematics and kinetics were evaluated during the execution of two sidestep cutting maneuvers (to 45 and 90 degrees) in twenty-five healthy soccer players. A two-way multivariate analysis of covariance (MANCOVA) determined that differences existed between task directions but not sexes when considering all dependent variables and covarying for approach velocity ( α ≤ 0.05). Post hoc analyses revealed that the larger deceleration and redirection demands of the 90-degree cut did not translate into larger angles, moments and power across all lower extremity joints. In the sagittal plane, the knee appeared to primarily accommodate the greater deceleration demands of the sharper cut. These data further suggest that the hip may play a different role during cutting to smaller and larger angles and also illustrate a pattern of engagement in the sagittal and frontal planes that has not been described previously. [ABSTRACT FROM AUTHOR]

Context: Excessive knee valgus during dynamic tasks is thought to contribute to lower extremity overuse and traumatic injuries. Clinically, assessments of frontal-plane knee motion typically include measures of the distance between the knees during landing. However, it is not clear how this clinical assessment relates to knee-abduction angle or how it is influenced by the position of the lower extremities in the transverse and frontal planes. Objective: To determine whether normalized knee separation distance (NKSD) is a predictor of knee-abduction angles and to assess the influence of lower extremity transverse-plane and frontal-plane angles on NKSD during a drop land. Design: Cross-sectional study. Setting: Motion analysis laboratory. Patients or Other Participants: Twenty-five healthy female athletes. Intervention(s): The frontal-plane distance between the 2-dimensional coordinates of markers over the greater trochanters (intertrochanteric distance), lateral femoral epicondyles (knee separation distance), and lateral malleoli (stance width) bilaterally was calculated during a drop land. The knee separation distance was normalized by intertrochanteric distance (NKSD). Concurrently, 3-dimensional lower extremity transverse-plane and frontal-plane kinematics were obtained. Main Outcome Measure(s): We assessed NKSD, stance width, and bilateral average knee and hip transverse plane and frontal-plane angles and ankle frontal-plane angles. Linear regression was used to determine the association between NKSD and bilateral average knee frontal-plane angles. Step- wise multiple regression was used to identify the best predictors of NKSD during the drop land. Results: After we controlled for stance width, NKSD explained 52% of the variance in the knee frontal-plane angle. When we took lower extremity kinematics into account, after controlling for stance width, the average hip frontal-plane angle was the best predictor of NKSD, explaining 97% of the variance. Conclusions: Although NKSD is a predictor of knee- abduction angle, frontal-plane hip angle and stance width are strongly related to NKSD. Caution must be taken when interpreting NKSD as knee abduction. [ABSTRACT FROM AUTHOR]

The article focuses on one study which examines knee mechanics among individuals who have performed side-step cutting right after a fatigue protocol as well as after 20 and 40 minutes of rests. 15 females aging 22 and 36 years and who have been exercising regularly at least three times per week for 30 minutes were the participants of the study. Reflective markers were then placed at their specific anatomic landmarks in order to measure their respective performance in side-step cutting task. Results revealed that fatigue does influence knee mechanics which are thought to be associated with anterior cruciate ligament (ACL) injury.

The article presents research into the physiology of young women soccer players. The role of the frontal plane extension of the knee at the finish of jumping in causing knee injuries is examined. Women soccer players were evaluated for knee extension, hip strength, and ankle range of motion during a series of jumps. A limited relationship was found between knee excursion and hip range of motion was found.

The article discusses the case study about gender differences in hip joint kinematics and kinetics during side-step cutting maneuver. The purpose of the study is to identify the gender differences in hip mechanics between female athletes who previously demonstrated greater knee valgus moments and their male counterparts. A chart showing the average three-dimensional hip joint angles and peak moments for female athletes during the early deceleration phase of a side-step cutting maneuver is presented.

The article discusses the influence of in-season injury prevention training on lower-extremity kinematics during a landing task in female soccer players. It involves eighteen female soccer players between the ages of 14 and 17, where all subjects are healthy with no current complaints of lower extremity injury. Based from the results, it has been found that following a season of soccer practice combined with injury prevention training, females demonstrated significantly hip internal rotation and greater hip abduction. It is therefore confirmed that the results support the premise that a season of practice with injury prevention training is effective in altering lower extremity motions, playing a role in predisposing females to anterior cruciate ligament injury.

Difficulty quantifying knee loading deficits clinically in individuals following anterior cruciate ligament reconstruction (ACLr) may underlie their persistence. Expense associated with quantifying knee moments (KMom) and power (KPow) with gold standard techniques precludes their use in the clinic. As segment and joint kinematics are used to calculate moments and power, it is possible that more accessible inertial sensor technology can be used to identify knee loading deficits. However, it is unknown if angular velocities measured with inertial sensors provide meaningful information regarding KMom/KPow during dynamic tasks post-ACLr. Twenty-one individuals 5.1 ± 1.5 months post-ACLr performed a single limb loading task, bilaterally. Data collected concurrently using a marker-based motion system and gyroscopes positioned lateral thighs/shanks. Intraclass correlation coefficients (ICC)(2,k) determined concurrent validity. To determine predictive ability of angular velocities for KMom/KPow, separate stepwise linear regressions performed using peak thigh, shank, and knee angular velocities extracted from gyroscopes. ICCs were greater than 0.947 (p < 0.001) for all variables. Thigh (r = 0.812 and r = 0.585; p < 0.001) and knee (r = 0.806 and r = 0.536; p < 0.001) angular velocities were strongly and moderately correlated to KPow and KMom, respectively. High ICCs indicated strong agreement between measurement systems. Thigh angular velocity (R2 = 0.66; p < 0.001) explained 66% of variance in KPow suggesting gyroscopes provide meaningful information regarding KPow. Less expensive inertial sensors may be helpful in identifying deficits clinically. [ABSTRACT FROM AUTHOR]

This study evaluated reliability of measures for superficial structures of the male pelvic floor (PF) obtained via transperineal sonography. Two embalmed cadavers were dissected to identify positioning of muscles on and around the bulb of the penis and to confirm the PF protocol. Cross-sectional area (CSA) and linear thickness of the bulb of the penis, urethra, bulbospongiosus (BS) muscles, and ischiocavernosus (IC) muscles were measured on 38 transverse images from 20 male patients by three raters with varied study knowledge and sonographic experience. Intra- and inter-rater reliability were calculated with two-way, mixed effects intra-class correlation coefficients. Measures of the bulb of the penis had the best reliability. CSA of all muscles and sagittal thickness of the BS near the central tendon had good reliability. Reliability varied for rater-identified thickest muscle region and measures of the urethra. Our study suggests that structures of the male PF can be reliably evaluated using a transperineal sonographic approach. [ABSTRACT FROM AUTHOR]

Background Following anterior cruciate ligament reconstruction, individuals exhibit sagittal plane knee loading deficits as they underload their injured limb during running. These between-limb biomechanical differences are difficult to clinically detect. Wearable accelerometers may aid in the development of early rehabilitation programs to improve symmetrical loading. This study aimed to identify whether segment accelerations from wearable accelerometers can predict knee loading asymmetry in an anterior cruciate ligament reconstructed population. Methods 14 individuals 5-months post-anterior cruciate ligament reconstruction performed self-selected speed running. Data were collected concurrently using a marker-based motion system and accelerometers positioned on participants' shanks and thighs. Stepwise linear regression was used to determine predictive value of accelerometer data on biomechanical variables. Finding Shank acceleration was not predictive of any biomechanical variable. Between-limb differences in thigh axial acceleration explained 30% of the variance in between-limb differences in knee power absorption (p = 0.045), suggesting that accelerometers placed on proximal joint segments may provide information regarding knee loading asymmetry. Between-limb differences in thigh axial acceleration also explained 38% of the variance in between-limb differences in ground reaction force (p = 0.002). Interpretation These relationships indicate that accelerations from wearable accelerometers may provide some useful information regarding knee loading during running in individuals following anterior cruciate ligament reconstruction. [ABSTRACT FROM AUTHOR]