Validation of OpenCap on lower extremity kinematics during functional tasks.

Marker-based motion capture is a fundamental tool in biomechanical analysis, yet comes with major constraints such as time, cost and accessibility. This study aimed to validate the use of OpenCap, a free, markerless motion capture system compared to a marker-based motion capture system to measure lower extremity kinematics during functional tasks. 20 individuals from an athletic population (18 females, 2 males) performed two gait trials (walking, running) and three functional tasks (double leg squat, countermovement jump, jump-landing).

Cumulative Impact Loading and Cartilage Synthesis Biomarkers May Be Associated With Injury Risk in Female Collegiate Basketball Players.

Purpose: To evaluate whether cumulative impact load and serum biomarkers are related to lower-extremity injury and to determine any impact load and cartilage biomarker relationships in collegiate female basketball athletes.

Methods: This was a prospective longitudinal study evaluating lower-extremity impact load, serum cartilage biomarkers, and injury incidence over the course of a single collegiate women's basketball season. Data were collected from August 2022 to April 2023; no other follow-up after the cessation of the season was conducted in this cohort.

Early- and Late-Stage Benefits of Blood Flow Restriction Training on Knee Strength in Adolescents After Anterior Cruciate Ligament Reconstruction.

Background: Blood flow restriction training (BFRT) after anterior cruciate ligament reconstruction (ACLR) is rising in popularity because of its benefits in reducing muscle atrophy and mitigating knee strength deficits.

Purpose: To investigate the impact BFRT has on adolescent knee strength after ACLR at 2 postoperative time points: at 3 months and the time of return to sport (RTS).

Study Design: Cohort study; Level of evidence, 3.

Meniscus Allograft Transplantation Augmented With Autologous Bone Marrow Aspirate Concentrate.

Meniscus allograft transplantation (MAT) has been shown to be a feasible surgical option for younger patients, below 50 years of age who have meniscal insufficiency and have failed conservative treatment measures. In this technical note, we describe a procedure of harvesting and injecting bone marrow aspirate concentrate in a meniscus allograft during a MAT procedure, which may allow for longer lasting transplants and improve patient outcomes. In this technical note, bone marrow aspirate concentrate is harvested arthroscopically from the intercondylar notch at the surgical site, which prevents additional donor site morbidity, as seen with harvesting from other locations, such as the iliac crest.

The Comparison of Psychological Barriers Between Individuals with a History of Anterior Knee Pain, Anterior Cruciate Ligament Reconstruction, and Healthy Individuals.

Background: Psychological barriers due to anterior knee pain (AKP) and anterior cruciate ligament reconstruction (ACLR) may have a direct impact on an individual's return to physical activity. A comprehensive understanding of these psychological barriers in individuals with AKP and ACLR may help clinicians to develop and implement better treatment strategies to address deficits that may exist in these individuals.

Hypothesis/purpose: The primary purpose of this study was to evaluate fear-avoidance, kinesiophobia, and pain catastrophizing in individuals with AKP and ACLR compared with healthy individuals.

Preventive Training Program Feedback Complexity, Movement Control, and Performance in Youth Athletes.

Context: Preventive training programs (PTPs) reduce injury risk by improving movement control. Corrective feedback is important; however, many cues at once may be too complicated for athletes.

Objective: To compare movement control and long-jump (LJ) changes in youth athletes participating in a season-long PTP, with simplified feedback, traditional feedback, or a warmup of the coaches' choosing.

Effectiveness of an Accelerated Rehabilitation Protocol After Tibial Tubercle Osteotomy.

Background: Patients with recurrent patellar dislocations with trochlear dysplasia are commonly treated surgically with a tibial tubercle osteotomy (TTO). Recovery and rehabilitation processes are often nonoperative out of concern for fixation failure or fracture. A more accelerated rehabilitation protocol allowing for early weightbearing and quadriceps strengthening may help to improve patient outcomes as long as complications are not increased.

The Utility of Functional Data Analyses to Reveal Between-Limbs Asymmetries in Those With a History of Anterior Cruciate Ligament Reconstruction.

Context: Researchers have traditionally used motion capture to quantify discrete data points (peak values) during hop testing. However, these analyses restrict the evaluation to a single time point (ie, certain percentage of stance) and provide only a narrow view of movement. Applying more comprehensive analyses may help investigators identify important characteristics that are masked by discrete analyses often used to screen patients for activity.

Reliability of wearable sensors to assess impact metrics during sport-specific tasks.

There is little information on the reliability of inertial measurement units for capturing impact load metrics during sport-specific movements. The purpose of this study is to determine the reliability of the Blue Trident IMU sensors in measuring impact load, step count and cumulative bone stimulus during a series of soccer-related tasks. Ten healthy recreational soccer players (age: 27.

Muscle Atrophy After ACL Injury: Implications for Clinical Practice.

Context: Distinct from the muscle atrophy that develops from inactivity or disuse, atrophy that occurs after traumatic joint injury continues despite the patient being actively engaged in exercise. Recognizing the multitude of factors and cascade of events that are present and negatively influence the regulation of muscle mass after traumatic joint injury will likely enable clinicians to design more effective treatment strategies. To provide sports medicine practitioners with the best strategies to optimize muscle mass, the purpose of this clinical review is to discuss the predominant mechanisms that control muscle atrophy for disuse and posttraumatic scenarios, and to highlight how they differ.

Morphology and Anabolic Response of Skeletal Muscles Subjected to Eccentrically or Concentrically Biased Exercise.

Context: Long-term eccentric exercise is known to promote muscle growth better than concentric exercise, but its acute effect on muscle is not well understood because of misinterpreted modeling and in situ and in vitro stretch protocols. Knowing if the initial bout of eccentric exercise promotes muscle growth and limits damage is critical to understanding the effect of this mode of exercise.

Objective: To directly evaluate the immediate effects of eccentric and concentric exercises on untrained muscle when fiber strains were physiological and exercise doses were comparable.

Examining the Relationship Between Neuroplasticity and Learned Helplessness After ACLR: Early Versus Late Recovery.

Context: Altered neural signaling is known to have a direct impact on psychological wellness. Therefore, disruptions in neural signaling after anterior cruciate ligament reconstruction may influence psychological dysfunction, in some cases manifesting as learned helplessness. Helplessness is a psychological paradigm that presents as altered neuromuscular control, reduced motivation, and psychological deficits.

Protracted alterations in muscle activation strategies and knee mechanics in patients after Anterior Cruciate Ligament Reconstruction.

Purpose: Altered quadriceps muscle activity can contribute to reduced ability of the muscle to quickly generate force and appropriately attenuate landing forces, exacerbating poor landing and movement strategies commonly seen after anterior cruciate ligament reconstruction (ACLR). The purpose was to evaluate if electromyographic (EMG) activity and knee biomechanics during a single-limb forward hop task are influenced by a history of ACLR.

Methods: Twenty-six individuals with a history of unilateral ACLR (age 20.

Male and Female Adolescent Athletes' Readiness to Return to Sport After Anterior Cruciate Ligament Injury and Reconstruction.

Objective: The purpose of this study was to examine whether readiness to return to sport (RTS) differed between adolescent male and female athletes after anterior cruciate ligament reconstruction (ACLR).

Design: Longitudinal, prospective cohort.

Setting: Outpatient office associated with tertiary-care hospital.

The relationship between single-limb squat and jump-cut kinematics.

No objective criteria exist for progressing athletes into cutting manoeuvres following ACL reconstruction (ACLR). The purpose of this study was to evaluate the relationship between a jump-cut task (JC) and the single-limb squat (SLS) in both ACLR and healthy controls. Case-control, laboratory based.

Alterations in physical and neurocognitive wellness across recovery after ACLR: A preliminary look into learned helplessness.

Objectives: Neural alterations after anterior cruciate ligament reconstruction (ACLR) may initiate a maladaptive neurocognitive response (learned helplessness [LH]). Understanding the interrelationships between neural inhibition, quadriceps function and psychological responses can provide clinicians areas to target during recovery. The purpose was to longitudinally evaluate neural excitability, strength and self-reported LH after ACL injury and to explore the relationship between these measures and knee mechanics and patient reported function.

Psychosocial Barriers After Anterior Cruciate Ligament Reconstruction: A Clinical Review of Factors Influencing Postoperative Success.

Context: Psychosocial factors arising after anterior cruciate ligament (ACL) injury may have a direct influence on an individual's decision to return to sport after ACL reconstruction (ACLR). While there is ample evidence to suggest that deficits in quadriceps strength, neuromuscular control, and clinical functional tasks exist after ACLR, the root and contribution of psychological dysfunction to an individual's success or return to sport after ACLR is still largely uncertain and unexplored. Given the discrepancy between successful functional outcomes and the percentage of athletes who return to sport, it is important to thoroughly address underlying factors, aside from physical function, that may be contributing to these lower return rates.

No shortage of disagreement between biomechanical and clinical hop symmetry after anterior cruciate ligament reconstruction.

Background: Evaluating average performance on functional hop tasks can potentially overestimate physical function, as it masks variability present within individual trials and may lead to clinician oversight regarding the overall movement quality. The purpose was to evaluate the trial-by-trial agreement between hop-distance symmetry and knee biomechanics (knee flexion angle, knee extension moment) to reveal the full extent of agreement between these measures.

Methods: Sixteen individuals with primary, unilateral anterior cruciate ligament reconstruction participated (age: 22(2) y; height: 1.

Quadriceps muscle function following anterior cruciate ligament reconstruction: systemic differences in neural and morphological characteristics.

Quadriceps muscle dysfunction is common following anterior cruciate ligament reconstruction (ACLR). Data considering the diversity of neural changes, in-concert with morphological adaptations of the quadriceps muscle, are lacking. We investigated bilateral differences in neural and morphological characteristics of the quadriceps muscle in ACLR participants (n = 11, month post-surgery: 69.

Learned Helplessness After Anterior Cruciate Ligament Reconstruction: An Altered Neurocognitive State?

Traumatic knee injuries, such as anterior cruciate ligament (ACL) sprains, have detrimental effects on long-term health as they initiate a cycle of chronic pain, physical inactivity, and disability. Alterations in strength and neural activity are factors that contribute to rehabilitation failure after ACL reconstruction (ACLR); however, psychological deficits also hinder rehabilitative success. Neural impairments observed following injury and ACLR may be associated with psychological dysfunction, a phenomenon defined as learned helplessness (LH).

Eccentric cross-exercise after anterior cruciate ligament reconstruction: Novel case series to enhance neuroplasticity.

Objectives: Substantial changes in neural function are historically present after anterior cruciate ligament reconstruction (ACLR), and are not rectified with traditional rehabilitation. Cross-exercise is a potential means to enhance neural excitability and improve recovery after ACLR. Hence our purpose, was to detail changes in brain activation, neural excitability and patient-reported outcomes in a cohort that completed an 8-week quadriceps-focused eccentric cross-exercise training program immediately following ACLR.

Clinical Outcome Measures and Return-to-Sport Timing in Adolescent Athletes After Anterior Cruciate Ligament Reconstruction.

Context:   Multiple factors are likely associated with an adolescent athlete's ability to return to play after anterior cruciate ligament (ACL) reconstruction (ACLR).

Objective:   To investigate the relationship between self-reported and functional outcome measures on return-to-play timing in an adolescent population, in athletes who returned and those who did not return to sport, and to identify a cutoff value for isometric quadriceps strength that could serve as a clinical target for maximizing the odds of returning to play after ACLR.

Design:   Cross-sectional study.

Decision to Return to Sport Participation After Anterior Cruciate Ligament Reconstruction, Part II: Self-Reported and Functional Performance Outcomes.

Context:   Anterior cruciate ligament (ACL) reconstruction (ACLR) is the most commonly used method for helping athletes regain function and return to preinjury activity levels after ACL injury. Outcomes after ACLR have suggested that athletes return to a level of function that would support a return to sport participation; however, in a recent meta-analysis, pooled return rates were only 55%. It is unclear whether this discrepancy is a result of functional impairments.