Biomechanical Measures of Neuromuscular Control and Valgus Loading of the Knee Predict Anterior Cruciate Ligament Injury Risk in Female Athletes

Background: Female athletes participating in high-risk sports suffer anterior cruciate ligament injury at a 4- to 6-fold greater rate than do male athletes. Hypothesis: Prescreened female athletes with subsequent anterior cruciate ligament injury will demonstrate decreased neuromuscular control and increased valgus joint loading, predicting anterior cruciate ligament injury risk. Study Design: Cohort study; Level of evidence, 2. Methods: There were 205 female athletes in the high-risk sports of soccer, basketball, and volleyball prospectively measured for neuromuscular control using 3-dimensional kinematics (joint angles) and joint loads using kinetics (joint moments) during a jump-landing task. Analysis of variance as well as linear and logistic regression were used to isolate predictors of risk in athletes who subsequently ruptured the anterior cruciate ligament. Results: Nine athletes had a confirmed anterior cruciate ligament rupture; these 9 had significantly different knee posture and loading compared to the 196 who did not have anterior cruciate ligament rupture. Knee abduction angle (P \u3c .05) at landing was 8° greater in anterior cruciate ligament–injured than in uninjured athletes. Anterior cruciate ligament–injured athletes had a 2.5 times greater knee abduction moment (P \u3c .001) and 20% higher ground reaction force (P \u3c .05), whereas stance time was 16% shorter; hence, increased motion, force, and moments occurred more quickly. Knee abduction moment predicted anterior cruciate ligament injury status with 73% specificity and 78% sensitivity; dynamic valgus measures showed a predictive r 2 of 0.88. Conclusion: Knee motion and knee loading during a landing task are predictors of anterior cruciate ligament injury risk in female athletes. Clinical Relevance: Female athletes with increased dynamic valgus and high abduction loads are at increased risk of anterior cruciate ligament injury. The methods developed may be used to monitor neuromuscular control of the knee joint and may help develop simpler measures of neuromuscular control that can be used to direct female athletes to more effective, targeted interventions

Biomechanical Measures of Neuromuscular Control and Valgus Loading of the Knee Predict Anterior Cruciate Ligament Injury Risk in Female Athletes

Background: Female athletes participating in high-risk sports suffer anterior cruciate ligament injury at a 4- to 6-fold greater rate than do male athletes. Hypothesis: Prescreened female athletes with subsequent anterior cruciate ligament injury will demonstrate decreased neuromuscular control and increased valgus joint loading, predicting anterior cruciate ligament injury risk. Study Design: Cohort study; Level of evidence, 2. Methods: There were 205 female athletes in the high-risk sports of soccer, basketball, and volleyball prospectively measured for neuromuscular control using 3-dimensional kinematics (joint angles) and joint loads using kinetics (joint moments) during a jump-landing task. Analysis of variance as well as linear and logistic regression were used to isolate predictors of risk in athletes who subsequently ruptured the anterior cruciate ligament. Results: Nine athletes had a confirmed anterior cruciate ligament rupture; these 9 had significantly different knee posture and loading compared to the 196 who did not have anterior cruciate ligament rupture. Knee abduction angle (P \u3c .05) at landing was 8° greater in anterior cruciate ligament–injured than in uninjured athletes. Anterior cruciate ligament–injured athletes had a 2.5 times greater knee abduction moment (P \u3c .001) and 20% higher ground reaction force (P \u3c .05), whereas stance time was 16% shorter; hence, increased motion, force, and moments occurred more quickly. Knee abduction moment predicted anterior cruciate ligament injury status with 73% specificity and 78% sensitivity; dynamic valgus measures showed a predictive r 2 of 0.88. Conclusion: Knee motion and knee loading during a landing task are predictors of anterior cruciate ligament injury risk in female athletes. Clinical Relevance: Female athletes with increased dynamic valgus and high abduction loads are at increased risk of anterior cruciate ligament injury. The methods developed may be used to monitor neuromuscular control of the knee joint and may help develop simpler measures of neuromuscular control that can be used to direct female athletes to more effective, targeted interventions

The Longitudinal Neurophysiological Adaptation of a Division I Female Lacrosse Player Following Anterior Cruciate Rupture and Repair: A Case Report

# Background Neurophysiological adaptation following anterior cruciate ligament (ACL) rupture and repair (ACLR) is critical in establishing neural pathways during the rehabilitation process. However, there is limited objective measures available to assess neurological and physiological markers of rehabilitation. # Purpose To investigate the innovative use of quantitative electroencephalography (qEEG) to monitor the longitudinal change in brain and central nervous systems activity while measuring musculoskeletal function during an anterior cruciate ligament repair rehabilitation. # Case Description A 19 year-old, right-handed, Division I NCAA female lacrosse midfielder suffered an anterior cruciate ligament rupture, with a tear to the posterior horn of the lateral meniscus of the right knee. Arthroscopic reconstruction utilizing a hamstring autograft and a 5% lateral meniscectomy was performed. An evidence-based ACLR rehabilitation protocol was implemented while using qEEG. # Outcomes Central nervous system, brain performance and musculoskeletal functional biomarkers were monitored longitudinally at three separate time points following anterior cruciate injury: twenty-four hours post ACL rupture, one month and 10 months following ACLR surgery. Biological markers of stress, recovery, brain workload, attention and physiological arousal levels yielded elevated stress determinants in the acute stages of injury and were accompanied with noted brain alterations. Brain and musculoskeletal dysfunction longitudinally reveal a neurophysiological acute compensation and recovering accommodations from time point one to three. Biological responses to stress, brain workload, arousal, attention and brain connectivity all improved over time. # Discussion The neurophysiological responses following acute ACL rupture demonstrates significant dysfunction and asymmetries neurocognitively and physiologically. Initial qEEG assessments revealed hypoconnectivity and brain state dysregulation. Progressive enhanced brain efficiency and functional task progressions associated with ACLR rehabilitation had notable simultaneous improvements. There may be a role for monitoring CNS/brain state throughout rehabilitation and return to play. Future studies should investigate the use of qEEG and neurophysiological properties in tandem during the rehabilitation progression and return to play

An Objective Method to Assess and Recommend Exertion and Exercise Targets for Return to Play Post concussion

Introduction. Concussions are of significant concern for athletic trainers, and there is a critical need to objectively and safely allow an athlete to return to play. In sports the objective is return as safely and soon as possible. Exertion is a consideration regarding progressing an athlete back to play. The ability to exert in cardiovascular and strength and conditioning contexts are two critical steps in most return to play protocols. Being able to make objective recommendations is urgently needed, as trial and error leads to unnecessary risk of eliciting symptoms and/or causing setbacks. Objective. The object of this paper is to present the athletic trainer with data associated with a methodology that can be used to aid in designing a cardiovascular and strength training program post concussion. This objective measure does not rely on subjective patient reports of symptoms and utilizes a reflex based assessment method. Description. The transient exertion related carotid (TERC) murmur is a murmur that is heard at the carotid arteries during exercise. It normally is heard at around a heart rate of 150, but is heard at lower heart rates in patients who have sustained a concussion. Listening for the TERC murmur during a cardiovascular and strength training assessment can be used to provide information to the athletic trainer about safer target heart rates or safer lifting strategies post-concussion. We present data concerning 71 athletes (mean age 20.8 years) who were assessed for cardiovascular conditioning and body weight assessment. With 73% of the cardio assessment subjects, a TERC murmur was detected at a heart rate of 127.2 bpm (± 16 SD). For the strength assessment 42.1% had a TERC murmur. Clinical advantages. The clinical advantage of the TERC murmur is that it can be utilized by any athletic trainer trained to take a blood pressure. It provides objective information concerning safe target heart rates that will allow an athletic trainer to recommend appropriate exercise prescriptions. The TERC murmur assessment can also be used to help guide strength training protocols to facilitate safe return. Being able to safely recommend a means by which an athlete can recommence their training (cardiovascular and/or strength training) may accelerate return to play as well as aid in keeping the athlete happy, healthy and engaged

Staphylococcus lugdunensis Septic Arthritis following Arthroscopic Anterior Cruciate Ligament Reconstruction

Summary. We report two cases of Staphylococcus lugdunensis (S. lugdunensis) septic arthritis following arthroscopic anterior cruciate ligament (ACL) reconstruction. Both initial surgical procedures were ACL reconstruction along with simultaneous collateral ligament and meniscus procedures. Patients presented with septic arthritis three and ten weeks following the index procedure. Both patients successfully recovered with early arthroscopic irrigation, debridement, and synovial culture, in addition to long-term parenteral and oral antibiotics