Development and implementation of an injury and illness surveillance system for team USA.

BACKGROUND: The purpose of this report is to provide insight and details regarding the development and implementation of an injury and illness surveillance (IIS) system for the United States Olympic and Paralympic Committee (USOPC). METHODS: The development and deployment of the IIS employed a multiphase approach. First, researchers determined variables to include in the IIS using the recommendations from the 2020 IOC consensus statement for reporting sport epidemiological data. Second, the hosting and deployment platforms were comprehensively evaluated for their suitability, ease of use, flexibility, and backend data structure (for both capture and aggregation). Third, focus groups consisting of the Sports Medicine department leadership and clinicians piloted the IIS system and revisions were made based on their feedback. Pilot testing of the IIS and follow-up focus groups were then conducted among all departmental clinicians to solicit additional feedback and drive further revisions. Finally, the IIS system was piloted among providers working during the 2023 Pan American and Parapan American Games to refine the system for future Games. After reviewing all potential software platform options (electronic medical record [EMR] system, athlete management systems, secure data collection platforms), Qualtrics (Qualtrics, Provo, UT, USA) was selected to host the IIS system. This choice was made due to the inability of the EMR and athlete-management systems to make frequent updates, modify existing questions, and provide the necessary form logic for the variety of scenarios in which the IIS system would be deployed. Feedback from the department's leadership and clinicians resulted in a number of changes, most notably being the ability to enter multiple diagnoses for a single injury event. Additionally, clinician feedback resulted in the creation of additional diagnostic codes not currently present in the OSIICS v14.0 diagnostic coding system, adding "non-sport" as an additional variable for injury setting, and developing a system for reporting return-to-sport date for time-loss injuries. DISCUSSION: A multi-stage process of extensive planning, stakeholder feedback, and ongoing updates is required in order to successfully develop and implement an IIS system within a National Olympic and Paralynpic Committee. This process can be used to inform the development and implementation of IIS systems in other sporting organizations.

High rates of respiratory illnesses upon arrival: lessons from Team USA at the Santiago 2023 Pan American and Parapan American Games.

OBJECTIVE: To describe the incidence and characteristics of injuries and illnesses among Team USA athletes competing at the Santiago 2023 Pan American Games (PAG) and Parapan American Games (PPAG), with a particular focus on the incidence of respiratory illnesses and on injuries for sports new to the Olympic and Paralympic programmes. METHODS: Illnesses and injuries occurring among the 870 Team USA athletes competing in the Santiago 2023 PAG or PPAG were documented within Team USA's Injury and Illness Surveillance system. Illness and injury incidence per 1000 athlete-days (ADs) and incidence ratios (IR) were calculated, both with 95% CIs. RESULTS: Illness (IR 2.5, 95% CI 1.6, 3.9) and injury (IR 1.8, 95% CI 1.3, 2.5) rates were greater during PPAG compared with PAG. Illness rates were higher in the pre-opening ceremony period compared with the competition period for both PAG (IR 2.7, 95% CI 1.1, 5.9) and PPAG (IR 1.9, 95% CI 0.9, 3.8). Respiratory illness was the most common illness with 3.2% and 8.9% of all Team USA athletes reporting a respiratory illness during the PAG and PPAG, respectively. Sports that are relatively new to the Olympic/Paralympic programmes exhibited the highest injury rates during the Games: breaking (250.0 (91.7, 544.2) per 1000 ADs), Para taekwondo (93.8 (19.3, 274.0) per 1000 ADs) and surfing (88.9 (24.2, 227.6) per 1000 ADs). CONCLUSION: Respiratory illness rates were the most common type of illness during both PAG and PPAG and were more likely to occur prior to competition starting. Our data have identified high injury risk populations (breaking, surfing, Para taekwondo) and timing (pre-opening ceremony period) for further risk factor analysis.

Persistent Early Knee Osteoarthritis Symptoms in the First Two Years After ACL Reconstruction.

CONTEXT: Early identification of knee osteoarthritis (OA) symptoms after anterior cruciate ligament reconstruction (ACLR) could enable timely interventions to improve long-term outcomes. However, little is known about the change in early OA symptoms from 6 to 12 months following ACLR. OBJECTIVE: To evaluate the change over time in meeting classification criteria for early knee OA symptoms from 6 to 12 months following ACLR. DESIGN: Prospective Cohort Study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: 82 participants aged 13-35 years who underwent unilateral primary ACLR. On average, participants' 1st and 2nd visits were 6.2 and 12.1 months post-ACLR. MAIN OUTCOME MEASURES: Early OA symptoms were classified using generic (Luyten Original) and patient population-specific (Luyten PASS) thresholds on Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales. Changes in meeting early OA criteria were compared between an initial and follow-up visit at an average of 6 and 12 months post-ACLR, respectively. RESULTS: Twenty-two percent of participants exhibited persistent early OA symptoms across both visits using both the Luyten Original and PASS criteria. From initial to follow-up visit, 18-27% had resolution of early OA symptoms while 4-9% developed incident symptoms. In total, 48-51% had no early OA symptoms at either visit. There were no differences between change in early OA status between adults and adolescents. CONCLUSIONS: Nearly one quarter of participants exhibited persistent early knee OA symptoms based on KOOS thresholds from 6 to 12 months post-ACLR. Determining if this symptom persistence predicts worse long-term outcomes could inform the need for timely interventions after ACLR. Future research should examine if resolving persistent symptoms in this critical window improves later outcomes. Tracking early OA symptoms over time may identify high-risk patients who could benefit from early treatment.

Lower Extremity Reaction Time in Individuals With Contact Versus Noncontact Anterior Cruciate Ligament Injuries After Reconstruction.

CONTEXT: Deficits in perceptual-motor function, like visuomotor reaction time (VMRT), are risk factors for primary and secondary anterior cruciate ligament (ACL) injury. Noncontact ACL injuries have been associated with slower reaction time, but whether this association exists for patients with contact ACL injuries is unknown. Exploring differences in VMRT among individuals with contact versus noncontact ACL injuries may provide a more comprehensive understanding of modifiable risk factors. OBJECTIVE: To compare lower extremity VMRT (LEVMRT) in individuals with contact or noncontact ACL injuries after ACL reconstruction (ACLR). DESIGN: Cross-sectional study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 36 participants with primary, unilateral ACLR completed an LEVMRT assessment (contact ACL injury = 20 [56%], noncontact ACL injury = 16 [44%]). MAIN OUTCOME MEASURE(S): The LEVMRT was assessed bilaterally and collected using a series of wireless light discs deactivated by individuals with their feet. The ACLR-active LEVMRT (ie, ACLR limb is deactivating lights) and ACLR-stable LEVMRT were compared using separate analyses of covariance to determine the association with contact or noncontact injury using time since surgery as a covariate. RESULTS: After controlling for time since surgery, a difference and large effect size between groups was found for the ACLR-stable LEVMRT (P = .010; η2 = 0.250) but not for the ACLR-active (P = .340; η2 = 0.065) condition. The contact group exhibited slower ACLR-stable LEVMRT (521.7 ± 59.3 milliseconds) than the noncontact group (483.4 ± 83.9 milliseconds). CONCLUSIONS: Individuals with contact ACL injury demonstrated a slower LEVMRT while their ACLR limb was stabilizing. The group differences during the ACLR-stable LEVMRT task might indicate deficits in perceptual-motor function when the surgical limb maintains postural control during a reaction time task. After ACLR, individuals with contact injuries may need additional motor learning interventions to enhance perceptual-motor functioning.

Psychological Readiness, Injury-Related Fear, and Persistent Knee Symptoms After Anterior Cruciate Ligament Reconstruction.

CONTEXT: Poor psychological responses after anterior cruciate ligament reconstruction (ACLR) have been associated with a failure to return to sport and increased secondary injury risk. However, we do not know whether poor psychological responses after ACLR influence patient-reported knee function and knee symptoms. OBJECTIVE: To examine the association between psychological factors (ie, psychological readiness and injury-related fear) and the presence of persistent knee symptoms in individuals 6 to 12 months after ACLR. DESIGN: Cross-sectional study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: In total, 101 participants, aged 13 to 25 years old, between 6 and 12 months after primary unilateral ACLR were enrolled in the study. MAIN OUTCOME MEASURE(S): Persistent knee symptoms were identified using an established criterion based on the subscales of the Knee injury and Osteoarthritis Outcome Score. Participants also completed the Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI) and the Tampa Scale of Kinesiophobia-11 (TSK-11) to assess psychological readiness and injury-related fear, respectively. Higher ACL-RSI scores indicate higher psychological readiness, and higher TSK-11 scores indicate higher injury-related fear. RESULTS: Twenty-nine participants (29%) met the criteria for persistent knee symptoms. For every 1 SD lower in the ACL-RSI score, participants had 2.1 times greater odds of persistent knee symptoms after ACLR (95% CI = 1.3, 3.6). For every 1 SD higher in the TSK-11 score, participants had 1.9 times greater odds of persistent knee symptoms after ACLR (95% CI = 1.1, 3.3). Both the ACL-RSI and TSK-11 were considered good at classifying persistent knee symptoms, as the areas under the curve were 0.78 and 0.73, respectively. CONCLUSIONS: Individuals with a lower level of psychological readiness and more injury-related fear after ACLR had greater odds of persistent knee symptoms. Overall, these results highlight the potential clinical benefit of a comprehensive, biopsychosocial approach to managing health and wellness for individuals after ACLR.

Psychological Readiness and Injury-Related Fear are Associated with Persistent Knee Symptoms after ACL Reconstruction.

CONTEXT: Poor psychological responses after anterior cruciate ligament reconstruction (ACLR) have been associated with failure to return to sport and increased secondary injury risk. However, we do not know whether poor psychological responses after ACLR influence patient-reported knee function and knee symptoms. OBJECTIVE: To examine the association between psychological factors (i.e., psychological readiness and injury-related fear) and the presence of persistent knee symptoms in individuals 6-12 months after ACLR. DESIGN: Cross-Sectional. SETTING: Research Laboratory. PATIENTS OR OTHER PARTICIPANTS: One-hundred and two participants, ages 13-25 years old, between 6 and 12 months post primary, unilateral ACLR were enrolled in the study. INTERVENTIONS(S): Persistent knee symptoms was identified using an established criterion based on the subscales of the Knee Injury and Osteoarthritis Outcome Score. MAIN OUTCOME MEASURE(S): Participants also completed the Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI) and the Tampa Scale of Kinesiophhobia-11 (TSK-11) to assess psychological readiness and injury-related fear, respectfully. Higher ACL-RSI scores indicate higher psychological readiness and higher TSK-11 scores indicate higher injury-related fear. RESULTS: Seventy participants (69%) met the criteria for persistent knee symptoms. For every standard deviation (SD) lower in ACL-RSI, a participants had 8.6 times greater odds of having persistent knee symptoms after ACLR (CI95: 3.3, 22.4). For every SD higher in TSK-11, a participants had 3.9 times greater odds of having persistent knee symptoms after ACLR (CI95: 2.1, 7.4). Both the ACL-RSI and TSK-11 were considered "good" at classifying persistent knee symptoms as areas under the curve were 0.88 and 0.83, respectfully. CONCLUSIONS: Individuals with lower psychological readiness and higher injury-related fear after ACLR have greater odds of experiencing persistent knee symptoms. Overall, these results highlight the potential clinical benefit for a comprehensive, biopsychosocial approach to managing health and wellness for individuals after ACLR.

Kinesiophobia Is Associated with Peak Knee Abduction Angle during Jump Landing after ACL Reconstruction.

INTRODUCTION: This study aimed to investigate the associations between kinesiophobia, knee abduction angle (KAA) during the first 100 ms of landing, and knee flexion excursion (KFE) in individuals 5-12 months after anterior cruciate ligament reconstruction (ACLR). We hypothesized that greater kinesiophobia would be associated with greater peak KAA and lesser KFE during landing on the ACLR limb, but not on the contralateral limb. METHODS: Thirty-six participants between 14 and 35 yr old (females = 19, age = 19.9 ± 5.1 yr, height = 172.5 ± 9.4 cm, weight = 76.7 ± 20.0 kg, time since surgery =7.2 ± 1.7 months) were recruited from a sports medicine clinic at 5-12 months after primary unilateral ACLR. Participants completed the Tampa Scale of Kinesiophobia-11 (TSK-11) to measure kinesiophobia and three successful trials of a standard drop vertical jump task. A 10-camera three-dimensional motion capture system synchronized with two embedded force plate platforms was used to capture jump-landing kinematics. Separate stepwise linear regression models were used to examine the associations between kinesiophobia, peak KAA, and KFE on the ACLR and contralateral limbs after accounting for time since surgery and biological sex. RESULTS: When accounting for time since surgery and biological sex, every 1-point increase on the TSK-11 (i.e., increase in kinesiophobia) associated with a 0.37° increase (i.e., a 7.1% increase) in ACLR limb KAA ( P = 0.02). Kinesiophobia was not associated with contralateral limb KAA, ACLR limb KFE, or contralateral limb KFE. CONCLUSIONS: Higher kinesiophobia was related to greater amounts of peak KAA during landing in individuals 5-12 months post-ACLR. Modifying kinesiophobia may help to decrease KAA and lead to reduced secondary ACL injury risk. Future research should investigate feasible psychological interventions to reduce kinesiophobia and improve KAA in patients post-ACLR.

Age-, Sex-, and Graft-Specific Reference Values From 783 Adolescent Patients at 5 to 7 Months After ACL Reconstruction: IKDC, Pedi-IKDC, KOOS, ACL-RSI, Single-Leg Hop, and Thigh Strength.

OBJECTIVE: To describe age-, sex-, and graft source-specific reference values for patient-reported, physical function, and strength outcome measures in adolescents at 5 to 7 months after anterior cruciate ligament reconstruction. DESIGN: Cross-sectional study. METHODS: Data were collected at 3 universities and 2 children's hospitals. The participants completed at least one of the International Knee Documentation Committee (IKDC) Subjective Evaluation Form, Pediatric IKDC (Pedi-IKDC), Knee Injury and Osteoarthritis Outcomes Score (KOOS), and Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) Scale. Participants also completed single-leg hop tests and/or isokinetic quadriceps and hamstrings strength assessments (at 60°/s). Reference values were summarized using descriptive statistics and stratified for age, sex, and graft source. RESULTS: Reference values were reported for common patient-reported outcomes and measures of physical function and strength from 783 participants (56% females, age = 16. 4 ± 2.0 years) who were in early adolescence (12-14 years, N = 183, 52% females), middle adolescence (15-17 years, N = 456, 58% females), or late adolescence (18-20 years, N = 144, 55% females). Three hundred seventy-nine participants (48.4%) received a bone-patellar tendon-bone autograft, 292 participants (37.3%) received hamstring tendon autograft, and 112 participants (14.3%) received autograft or allograft from an alternative source. CONCLUSION: Reference values for common patient-reported outcomes and measures of physical function and strength differed depending on a patient's age, sex, and graft source. Using patient-specific reference values, in addition to previously described age-appropriate cutoff values, may help clinicians monitor and progress patients through rehabilitation and return to physical activity after anterior cruciate ligament reconstruction. J Orthop Sports Phys Ther 2023;53(4):1-8. Epub: 23 January 2023. doi:10.2519/jospt.2023.11389.

Validation of a Survey to Characterize Barriers to Physical Activity After Anterior Cruciate Ligament Reconstruction.

CONTEXT: Although 84% of patients expected to return to activity within 1 year of anterior cruciate ligament (ACL) reconstruction (ACLR), as few as 24% will return to their preinjury level of activity. By considering a patient's perceptions of reengagement in activity after ACLR, clinicians and researchers may be better equipped to implement interventions that are patient centered. OBJECTIVE: To describe the validation of the ACL Reasons survey, a tool to aid clinicians and researchers in understanding patient perceptions of barriers to physical activity (PA) engagement after ACLR. DESIGN: Cross-sectional study. PATIENTS OR OTHER PARTICIPANTS: The ACL Reasons survey was administered via Qualtrics to 78 patients 6 to 24 months after primary, unilateral ACLR. Patients were categorized as active, more challenging, or less active based on their responses to the ACL Reasons. MAIN OUTCOME MEASURE(S): Development of the ACL Reasons survey occurred via an iterative process of drafting and revising based on feedback from a team of external expert reviewers. Tegner activity level, Marx activity score, the Knee injury and Osteoarthritis Outcomes Score (KOOS), ACL Return to Sport after Injury score, and Tampa Scale of Kinesiophobia score were compared among groups using analysis-of-variance and Kruskal Wallis tests. RESULTS: Groups differed based on Tegner activity level (P < .001), Marx activity score (P = .01), KOOS pain score (P = .02), KOOS symptom score (P = .04), KOOS sports and recreation score (P < .001), KOOS quality of life score (P < .001), ACL Return to Sport after Injury score (P < .001), and Tampa Scale of Kinesiophobia score (P < .001), with the less active group performing worse on each. Knee symptoms, fear of knee symptoms or movement, and fear of injury were the most common reasons for the change in PA engagement. CONCLUSIONS: These results support the validity of the ACL Reasons survey as a tool for identifying barriers to PA engagement after ACLR. This tool may help facilitate communication between patients with ACLR and their health care providers to enhance patient-centered care.

Quadriceps Strength and Knee-Related Symptom State 6 Months After Anterior Cruciate Ligament Reconstruction.

CONTEXT: Isometric quadriceps strength metrics and patient-reported outcomes are commonly used in return-to-sport assessments in those with anterior cruciate ligament reconstruction (ACLR). Patients may experience clinical knee-related symptoms aggravating enough to seek additional medical care after ACLR. In addition to seeking additional medical care, these patient-reported clinical knee-related symptoms may also influence function after ACLR. However, whether an association exists between these common quadriceps metrics and the patient-reported clinical knee-related symptom state is unknown. OBJECTIVE: To determine if meeting isometric quadriceps strength and symmetry criteria is associated with acceptable clinical knee-related symptoms at 5 to 7 months post-ACLR. DESIGN: Cross-sectional study. SETTING: Laboratories. PATIENTS OR OTHER PARTICIPANTS: We classified individuals at 5 to 7 months post-ACLR based on their isometric ACLR and uninvolved-limb quadriceps strength or quadriceps strength symmetry. We also dichotomized participants based on the Englund et al criteria for unacceptable clinical knee-related symptoms. MAIN OUTCOME MEASURE(S): Quadriceps strength variables were compared between groups using analysis of covariance, and the relative risk of a participant in each quadriceps strength group reporting acceptable clinical knee-related symptoms was determined using binary logistic regression. RESULTS: A total of 173 individuals participated. The isometric quadriceps strength and limb symmetry index were different (P < .001) between quadriceps strength groups. Those categorized as both strong and symmetric had a 1.28 (95% CI = 0.94, 1.74) and individuals categorized as symmetric only had a 1.29 (95% CI = 0.97, 1.73) times greater relative risk of reporting acceptable clinical knee-related symptoms compared with the neither strong nor symmetric group. CONCLUSIONS: The majority of individuals (85%) recovering from ACLR failed to meet either the clinical quadriceps strength or symmetry criteria at 5 to 7 months post-ACLR. Quadriceps strength and quadriceps strength symmetry are clinically important but may not be primary determinants of the clinical knee-related symptom state within the first 6 months post-ACLR.

Adolescents Are Less Physically Active Than Adults After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Sources of physical activity (PA) and motivation for return to sport after anterior cruciate ligament reconstruction (ACLR) differ between adolescents and adults. It is unclear whether these differences influence participation in PA during the first year after ACLR when individuals are transitioning from rehabilitative care to unrestricted activity. PURPOSE: To compare device-assessed measures of PA between adolescents and adults at 6 to 12 months after ACLR. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Included were 22 adolescents (age, 15.9 ± 1.2 years; time since surgery = 8.0 ± 2.1 months) and 23 adults (age, 22.5 ± 5.0 years; time since surgery = 8.2 ± 2.1 months) who were cleared for unrestricted PA after primary unilateral ACLR. Participants were considered physically active if they met their age-specific United States Department of Health and Human Services PA guidelines. Participants wore an accelerometer-based PA monitor for at least 7 days. Daily minutes of moderate to vigorous-PA (MVPA) and daily step counts were reported and compared between age groups using analysis of covariance, with monitor wear time and sex included as covariates. The association between age group and meeting age-specific PA guidelines was assessed using binary logistic regression and reported as an odds ratio. RESULTS: Adults with ACLR participated in 16 minutes more MVPA per day (49 ± 22 vs 33 ± 16 minutes per day; P < .001) and took 2212 more steps per day (8365 ± 2294 vs 6153 ± 1765 steps per day; P < .001) when compared with adolescent participants. In addition, 83% of adults were physically active, compared with 9% of adolescents (odds ratio = 60.2; 95% CI, 7.6-493.4). CONCLUSION: Adolescents with ACLR were less physically active than adults with ACLR, and only 9% of adolescents met aerobic PA guidelines. This is concerning because PA patterns adopted early in life are predictive of PA patterns in adulthood. Our findings indicate a need to better understand underlying causes of reduced PA among adolescents with ACLR and to develop intervention strategies that promote engagement in adequate PA after rehabilitation.

Physical Activity Engagement Worsens Health Outcomes and Limits Exercise Capacity in Growth-restricted Mice.

INTRODUCTION: A total of 161 million children a year are growth restricted, leading to a 47% increased risk of chronic disease in adulthood. Physical activity (PA) reduces the risk of mortality from chronic disease. The purpose of the present investigation was to determine the effect of a PA intervention (wheel running) on cardiac and skeletal muscle capacities in gestational (GUN) and postnatal (PUN) growth-restricted mice as compared with nonrestricted controls (CON). METHODS: A low-protein cross-fostering FVB mouse model was used to induce growth restriction during gestation and the first 21 d of postnatal life. Mouse pups were recovered on a healthy diet until mature and provided wheel access for 3 wk. At completion of the PA intervention, mice underwent maximal exercise testing on a treadmill, echocardiography, and skeletal muscle histology. RESULTS: After the PA intervention, CON mice had a 45% improvement in maximal exercise capacity (P = 0.0390) because of cardiac and skeletal muscle adaptations, but GUN and PUN mice did not. Alarmingly, PUN female mice exposed to wheels had 11.45% lower left ventricular volume (P = 0.0540) and 18% lower left ventricle area (P = 0.0585), with blood flow velocities indicative of cardiac fibrosis (GUN had elevated isovolumetric contraction time P = 0.0374; GUN females and PUN males had longer isovolumetric relaxation time P = 0.0703). PUN male mice had mixed skeletal muscle responses with an oxidative shift in the diaphragm (P = 0.0162) but a glycolytic shift in the extensor digitorum longus (P = 0.0647). PUN female mice had a glycolytic shift in the soleus after wheel running. CONCLUSIONS: Unexpectedly, growth-restricted mice were nonresponders to a PA intervention and displayed negative cardiac outcomes.

Characterizing body composition, cardiorespiratory fitness, and physical activity in women with anterior cruciate ligament reconstruction.

OBJECTIVES: The purpose was to compare body composition, cardiorespiratory fitness, and physical activity (PA) engagement between women with ACLR and healthy controls. DESIGN: Cross-sectional study. SETTING: University laboratory. PARTICIPANTS: Ten women with ACLR (time since surgery = 33.0 ± 18.3 months; age = 21.4 ± 3.8 years) and 10 healthy women (age = 21.9 ± 3.1 years) matched based on age (±2 years) and Tegner Activity Level (±2) participated. MAIN OUTCOME MEASURES: Body fat percentage (%BF) was estimated using air displacement plethysmography, cardiorespiratory fitness was assessed via a graded cycle test, and PA was assessed using accelerometers worn for 7 days. Groups were compared using Mann-Whitney U tests. Time (minutes/week) spent in moderate-to-vigorous PA and step count (steps/day) were compared between groups using a one-way ANCOVA with 7-day total wear time as the only covariate. Statistical significance was established a priori as α ≤ 0.05. RESULTS: Women with ACLR had significantly higher %BF than controls (ACLR = 32.7 ± 6.7%, healthy = 22.6 ± 4.9%; p < 0.01) and participated in less steps per day (ACLR = 6650 ± 3227 steps/day, healthy = 9361 ± 2626 steps/day; p = 0.02). CONCLUSIONS: There may be persistent negative effects on body composition and PA engagement for women following ACLR. Low PA and high %BF have adverse consequences for premature mortality and morbidity; therefore, it is crucial to assess these characteristics and determine interventions to maintain PA and healthy body composition following ACLR.

A Comparison of Psychological Readiness and Patient-Reported Function Between Sexes After Anterior Cruciate Ligament Reconstruction.

CONTEXT: Postoperative functional and return-to-sport outcomes after anterior cruciate ligament reconstruction (ACLR) differ by sex. However, whether sex disparities are observed in patient-reported outcome measures (PROMs) before return to sport after ACLR is unclear. OBJECTIVES: To compare common PROMs between young men and women who had not yet returned to sport after ACLR. DESIGN: Cross-sectional study. SETTING: University laboratory. PATIENTS OR OTHER PARTICIPANTS: Forty-five young men (age = 18.7 ± 2.7 years, time since surgery = 6.8 ± 1.4 months) and 45 women matched for age (±1 year) and time since surgery (±1 month; age = 18.8 ± 2.8 years, time since surgery = 6.9 ± 1.4 months) with ACLR participated. MAIN OUTCOME MEASURE(S): Participants completed the Tegner Activity Scale, ACL Return to Sport After Injury scale, Tampa Scale of Kinesiophobia, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Score, and Knee Injury and Osteoarthritis Outcome Score (KOOS). The PROMs were compared between men and women using Mann-Whitney U tests. Odds ratios were calculated to evaluate the odds of a male reporting a PROM value above the previously established normative value as compared with a female. RESULTS: Sex differences were present for the IKDC score (P = .01) and KOOS Pain score (P = .04) but not for the Tegner Activity Scale (P = .22), ACL Return to Sport After Injury scale score (P = .78), Tampa Scale of Kinesiophobia score (P = .64), or other KOOS subscales (P values = .40 to .52). The odds of reporting values above normative levels differed only for the IKDC score (odds ratio = 2.72, 95% confidence interval = 1.16, 6.38). CONCLUSIONS: After ACLR, young men and women reported similar levels of knee-related function, fear of movement, and readiness for return to sport and were equally likely to meet clinically meaningful normative values before return to sport. Overreliance on patient reports or objective functional outcomes in evaluating patient progress and readiness for return to sport after ACLR may limit clinicians in their ability to comprehensively evaluate and develop individualized interventional approaches that optimize patient outcomes.

Early life undernutrition reduces maximum treadmill running capacity in adulthood in mice.

Undernutrition during early life causes chronic disease with specific impairments to the heart and skeletal muscle. The purpose of this study was to determine the effects of early life undernutrition on adult exercise capacity as a result of cardiac and skeletal muscle function. Pups were undernourished during gestation (GUN) or lactation (PUN) using a cross-fostering nutritive mouse model. At postnatal day 21, all mice were weaned and refed a control diet. At postnatal day 67, mice performed a maximal treadmill test. Echocardiography and Doppler blood flow analysis was performed at postnatal day 72, following which skeletal muscle cross-sectional area (CSA) and fiber type were determined. Maximal running capacity was reduced (diet: P = 0.0002) in GUN and PUN mice. Left ventricular mass (diet: P = 0.03) and posterior wall thickness during systole (diet × sex: P = 0.03) of GUN and PUN mice was reduced, causing PUN mice to have reduced (diet: P = 0.04) stroke volume. Heart rate of GUN mice showed a trend (diet: P = 0.07) towards greater resting values than other groups. PUN mice had greater CSA of soleus fibers. PUN had a reduced (diet: P = 0.03) proportion of type-IIX fibers in the extensor digitorum longus (EDL) and a greater (diet: P = 0.008) percentage of type-IIB fibers in the EDL. In conclusion, gestational and postnatal undernourishment impairs exercise capacity.

Quadriceps Muscle Size Following ACL Injury and Reconstruction: A Systematic Review.

Image-based assessments of quadriceps muscle size facilitate examination of structural changes after anterior cruciate ligament (ACL) injury and reconstruction (ACLR). Understanding the effects of ACLR on muscle size measures may aid in clarifying the contribution of quadriceps atrophy toward quadriceps strength. The purpose of this study was to systematically review the literature examining the effects of ACLR on quadriceps muscle volume and cross-sectional area (CSA). An online database search was conducted using Web of Science, SportDISCUS, PubMed (Medline), CINHAL (EBSCO), and Cochrane Library limited to articles published after January 1, 1980. Means and standard deviations were extracted for the ACLR limb and the contralateral limb, and sample characteristics from relevant articles. Magnitude of between limb differences were assessed using pooled effect sizes (Hedge's g) and 95% confidence intervals. Eleven articles (five CSA, six muscle volume) were included in this systematic review. Included studies reported negative effective sizes, indicating that the ACLR limb was smaller in CSA or muscle volume compared with the contralateral limb; however, 36% of the included articles reported meaningful difference between the limbs. Quadriceps atrophy may occur following ACL injury and persist after rehabilitation, however, the magnitude of these reductions may not be clinically meaningful and may only partially explain the persistent quadriceps weakness that is ubiquitous among this patient population. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:598-608, 2020.

Sex differences in quadriceps rate of torque development within 1 year of ACL reconstruction.

OBJECTIVES: To investigate the effect of sex on measures of quadriceps strength, rate of torque development, and knee function during the first year following ACLR. DESIGN: Cross-sectional; SETTING: University community; PARTICIPANTS: Sixty individuals (29 men) with unilateral ACLR in the last 12 months. MAIN OUTCOME MEASURES: Participants completed bilateral knee extension maximal voluntary isometric contraction (MVIC, Nm/kg) strength assessments. Rates of torque development (Nm*kg-1*s-1) were assessed from contraction initiation to 100 ms (RTD100) and from 100 ms to 200 ms after contraction initiation (RTD200). The effects of sex MVIC strength, RTD, and limb symmetry were assessed using separate ANCOVAs. RESULTS: Women displayed weaker involved limb (Men = 2.72 ±â€¯0.72 Nm*kg-1, Women = 2.01 ±â€¯0.50 Nm*kg-1, p < 0.001) and contralateral limb (Men = 3.15 ±â€¯0.52 Nm*kg-1, Women = 2.66 ±â€¯0.58 Nm*kg-1, p < 0.001) MVIC, and slower involved limb RTD100 (Men = 8.36 ±â€¯3.16 Nm*kg-1*s-1, Women = 6.50 ±â€¯2.41 Nm*kg-1*s-1, p = 0.01) and RTD200 (Men = 9.49 ±â€¯3.45 Nm*kg-1*s-1, Women = 9.49 ±â€¯3.45 Nm*kg-1*s-1, p < 0.001) when compared to men. CONCLUSIONS: Within the first year after ACLR, women displayed bilateral quadriceps weakness and slower involved limb quadriceps RTD when compared to men. Specific focus on facilitating quadriceps hypertrophy and improving neural drive to the quadriceps is indicated when treating female patients attempting to make a return to sport after ACLR.

Changes in collegiate ice hockey player anthropometrics and aerobic fitness over 3 decades.

Over the past several decades, an increased emphasis on fitness training has emerged among collegiate ice hockey teams, with the objective of improving on-ice performance. However, it is unknown if this increase in training has translated over time into changes in the anthropometric and fitness profiles of collegiate ice hockey players. The purposes of this study were to describe anthropometric (height, weight, body mass index (BMI), percent body fat (%fat)) and aerobic fitness (peak oxygen consumption) characteristics of collegiate ice hockey players over a period of 36 years and to evaluate whether these characteristics differ among player positions. Anthropometric and physiologic data were obtained through preseason fitness testing of players (N = 279) from a National Collegiate Athletic Association Division I men's ice hockey team from the years 1980 through 2015. Changes over time in the anthropometric and physiologic variables were evaluated via regression analysis using linear and polynomial models, and differences among player positions were compared via ANOVA (p < 0.05). Regression analysis revealed that a cubic model best predicted changes in mean height (R2 = 0.65), weight (R2 = 0.77), and BMI (R2 = 0.57), whereas a quadratic model best fit change in %fat by year (R2 = 0.30). Little change was observed over time in the anthropometric characteristics. Defensemen were significantly taller than forwards (184.7 ± 12.1 vs. 181.3 ± 5.9 cm) (p = 0.007), and forwards had a higher relative peak oxygen consumption compared with defensemen (58.7 ± 4.7 vs. 57.2 ± 4.4 mL·kg-1·min-1) (p = 0.032). No significant differences were observed in %fat or weight by position. Although average player heights and weights fluctuated over time, increased emphasis on fitness training did not affect the athletes' relative aerobic fitness. Differences in height and aerobic fitness levels were observed among player positions.

Expression of Adipocyte/Macrophage Fatty Acid-Binding Protein in Tumor-Associated Macrophages Promotes Breast Cancer Progression.

Tumor-associated macrophages (TAM) play a critical role in cancer development and progression. However, the heterogeneity of TAM presents a major challenge to identify clinically relevant markers for protumor TAM. Here, we report that expression of adipocyte/macrophage fatty acid-binding protein (A-FABP) in TAM promotes breast cancer progression. Although upregulation of A-FABP was inversely associated with breast cancer survival, deficiency of A-FABP significantly reduced mammary tumor growth and metastasis. Furthermore, the protumor effect of A-FABP was mediated by TAM, in particular, in a subset of TAM with a CD11b+F4/80+MHCII-Ly6C- phenotype. A-FABP expression in TAM facilitated protumor IL6/STAT3 signaling through regulation of the NFκB/miR-29b pathway. Collectively, our results suggest A-FABP as a new functional marker for protumor TAM.Significance: These findings identify A-FABP as a functional marker for protumor macrophages, thus offering a new target for tumor immunotherapy. Cancer Res; 78(9); 2343-55. ©2018 AACR.

Effects of deuterium oxide on cell growth and vesicle speed in RBL-2H3 cells.

For the first time we show the effects of deuterium oxide on cell growth and vesicle transport in rat basophilic leukemia (RBL-2H3) cells. RBL-2H3 cells cultured with 15 moles/L deuterium showed decreased cell growth which was attributed to cells not doubling their DNA content. Experimental observations also showed an increase in vesicle speed for cells cultured in deuterium oxide. This increase in vesicle speed was not observed in deuterium oxide cultures treated with a microtubule-destabilizing drug, suggesting that deuterium oxide affects microtubule-dependent vesicle transport.