Pooled Analysis of Trauma Centers Better Predicts Risk Factors for Firearm Violence Reinjury.

INTRODUCTION: Many trauma centers use the first firearm injury admission as a reachable moment to mitigate reinjury. Understanding repeat firearm violence can be difficult in metropolitan areas with multiple trauma centers and laws that prohibit sharing private health information across health systems. We hypothesized that risk factors for repeat firearm violence could be better understood using pooled data from two major metropolitan trauma centers. METHODS: Two level I trauma center registries were queried (2007-2017) for firearm injury admissions using International Classification of Diseases, Ninth and Tenth Revision (ICD9/10) Ecodes. A pseudo encryption tool allowed sharing of deidentified firearm injury and repeat firearm injury data without disclosing private health information. Factors associated with firearm reinjury admissions including, age, sex, race, payor, injury severity, intent, and discharge, were assessed by multivariable logistic regression. RESULTS: We identified 2145 patients with firearm injury admissions, 89 of whom had a subsequent repeat firearm injury admission. Majority of repeat firearm admissions were assaulted (91%), male (97.8%), and non-Hispanic Black (86.5%). 31.5% of repeat firearm injury admissions were admitted to a different trauma center from their initial admission. Independent predictors of repeat firearm injuries were age (adjusted odds ratio [aOR] 0.94, P < 0.001), male sex (aOR 6.18, P = 0.013), non-Hispanic Black race (aOR 5.14, P = 0.007), or discharge against medical advice (aOR 6.64, P=<0.001). CONCLUSIONS: Nearly a third of repeat firearm injury admissions would have been missed in the current study without pooled metropolitan trauma center data. The incidence of repeat firearm violence is increasing and those at the highest risk for reinjury need to be targeted for mitigating interventions.

Corticomuscular cross-recurrence analysis reveals between-limb differences in motor control among individuals with ACL reconstruction.

Surgical reconstruction of the anterior cruciate ligament (ACL) and subsequent physical therapy can help athletes return to competition; however, re-injury rates remain disproportionately high due, in part, to lingering biomechanical and neurological factors that are not fully addressed during rehabilitation. Prior reports indicate that individuals exhibit altered electrical activity in both brain and muscle after ACL reconstruction (ACLR). In this investigation, we aimed to extend existing approaches by introducing a novel non-linear analysis of corticomuscular dynamics, which does not assume oscillatory coupling between brain and muscle: Corticomuscular cross-recurrence analysis (CM-cRQA). Our findings indicate that corticomuscular dynamics vary significantly between involved (injured) and uninvolved legs of participants with ACLR during voluntary isometric contractions between the brain and both the vastus medialis and lateralis. This finding points to a potential lingering neural deficit underlying re-injury for athletes after surgical reconstruction, namely the dynamical structure of neuromuscular (brain to quad muscle) coordination, which is significantly asymmetric, between limbs, in those who have ACLR.

Reinjury Following Return to Play.

Radiologists are frequently called on for guidance regarding return to play (RTP) for athletes and active individuals after sustaining a musculoskeletal injury. Avoidance of reinjury is of particular importance throughout the rehabilitative process and following resumption of competitive activity. Understanding reinjury risk estimation, imaging patterns, and correlation of clinical and surgical findings will help prepare the radiologist to identify reinjuries correctly on diagnostic imaging studies and optimize management for a safe RTP.

Epidemiology of quadriceps muscle strain injuries in elite male Australian football players.

OBJECTIVE: To describe the epidemiology of quadriceps muscle strain injury (QMSI) in elite Australian Football League (AFL) players, explore recovery milestones and determine whether recovery is impacted by factors such as injury type (index vs. re-injury), the primary muscle injured and the mechanism of injury. MEASURES: All QMSI data reported to the Soft Tissue Injury Registry of the AFL from the 2014 to 2020 seasons were evaluated. Player demographic data, circumstances of injury, MRI reports and recovery outcomes following injury were extracted. Descriptive statistics and frequency distributions are presented. Recovery outcomes for injury type, primary muscle injured and the mechanism of injury were compared using univariate analyses. RESULTS: There were 164 QMSIs from 122 players reported (134 index; 30 re-injuries). Almost all (91.3%) QMSIs involved the rectus femoris. Half (48.4%) of the QMSIs occurred during kicking and most commonly affected the dominant kicking leg (72%). The majority occurred at training (64.6%). All re-injuries involved the rectus femoris, most occurred from kicking (63.0%) and within 6 months of the preceding injury (70%). The mean return to play (RTP) time was 25.4 days (95%CI = 22.6-28.2) and rectus femoris injuries took around 14 days longer to RTP than vastii injuries (p = 0.001). QMSIs with a kicking mechanism took the longest to RTP of all injury mechanisms. CONCLUSION: In AFL players, QMSIs occur mostly in the dominant leg from a kicking mechanism. Rectus femoris injuries are more prevalent and result in longer RTP time frames. Re-injuries exclusively involved the rectus femoris, primarily from kicking.

Are all hamstring injuries equal? A retrospective analysis of time to return to full training following BAMIC type 'c' and T-junction injuries in professional men's rugby union.

We aimed to determine whether the anatomical location (intramuscular tendon or T-Junction) of hamstring muscle injuries in professional men's rugby union associates with a prolonged time to return to full training and a higher rate of re-injury/subsequent injury. We reviewed the medical records of an Irish professional rugby union club to identify hamstring muscle injuries incurred across five seasons. Clinicians and players were not blinded to MRI results at the time of rehabilitation. A blinded musculoskeletal radiologist re-classified all included injuries (n = 91) according to the British Athletics Muscle Injury Classification framework. Players who sustained an injury with intramuscular tendon involvement required a longer time to return to full training compared to players who sustained an injury without intramuscular tendon involvement (78 days vs. 24 days). Players who sustained a biceps femoris injury with T-junction involvement did not require a longer time to return to full training compared to players who sustained a biceps femoris injury without T-junction involvement (29 days vs. 27 days). Injuries with either intramuscular tendon or T-junction involvement were not associated with an increased rate of re-injury/subsequent injury to the same limb (intramuscular tendon involvement - odds ratio = 0.96, T-junction involvement - odds ratio = 1.03). When a hamstring muscle injury involves the intramuscular tendon, the injured player and stakeholders should be made aware that a longer time to return to full training is likely required. T-junction involvement does not alter the expected clinical course of biceps femoris injuries.

Can a Psychologic Profile Predict Successful Return to Full Duty After a Musculoskeletal Injury?

BACKGROUND: Psychologic variables have been shown to have a strong relationship with recovery from injury and return to work or sports. The extent to which psychologic variables predict successful return to work in military settings is unknown. QUESTIONS/PURPOSES: In a population of active duty soldiers, (1) can a psychologic profile determine the risk of injury after return to full duty? (2) Do psychologic profiles differ between soldiers sustaining injuries in the spine (thoracic or lumbar) and those with injuries to the lower extremities? METHODS: Psychologic variables were assessed in soldiers returning to full, unrestricted duty after a recent musculoskeletal injury. Most of these were noncombat injuries from work-related physical activity. Between February 2016 and September 2017, 480 service members who were cleared to return to duty after musculoskeletal injuries (excluding those with high-velocity collisions, pregnancy, or amputation) were enrolled in a study that tracked subsequent injuries over the following year. Of those, we considered individuals with complete 12-month follow-up data as potentially eligible for analysis. Based on that, approximately 2% (8 of 480) were excluded because they did not complete baseline surveys, approximately 2% (11 of 480) were separated from the military during the follow-up period and had incomplete injury data, 1% (3 of 480) were excluded for not serving in the Army branch of the military, and approximately 2% (8 of 480) were excluded because they were not cleared to return to full duty. This resulted in 450 soldiers analyzed. Individuals were 86% (385 of 450) men; 74% (331 of 450) had lower extremity injuries and 26% (119 of 450) had spinal injuries, including soft tissue aches and pains (for example, strains and sprains), fractures, and disc herniations. Time-loss injury within 1 year was the primary outcome. While creating and validating a new prediction model using only psychological variables, 19 variables were assessed for nonlinearity, further factor selection was performed through elastic net, and models were internally validated through 2000 bootstrap iterations. Performance was deciphered through calibration, discrimination (area under the curve [AUC]), R 2 , and calibration in the large. Calibration assesses predicted versus actual risk by plotting the x and y intersection of these values; the more similar predicted risk values are to actual ones, the closer the slope of the line formed by the intersection points of all subjects is to equaling "1" (optimal calibration). Likewise, perfect discrimination (predicted injured versus actual injured) presents as an AUC of 1. Perfect calibration in the large would equal 0 because it represents the average predicted risk versus the actual outcome rate. Sensitivity analyses stratified groups by prior injury region (thoracic or lumbar spine and lower extremity) as well as the severity of injury by days of limited duty (moderate [7-27 days] and severe [28 + days]). RESULTS: A model comprising primarily psychologic variables including depression, anxiety, kinesiophobia, fear avoidance beliefs, and mood did not adequately determine the risk of subsequent injury. The derived logistic prediction model had 18 variables: R 2 = 0.03, calibration = 0.63 (95% confidence interval [CI] 0.30 to 0.97), AUC = 0.62 (95% CI 0.52 to 0.72), and calibration in the large = -0.17. Baseline psychologic profiles between body regions differed only for depression severity (mean difference 1 [95% CI 0 to 1]; p = 0.04), with greater mean scores for spine injuries than for lower extremity injuries. Performance was poor for those with prior spine injuries compared with those with lower extremity injuries (AUC 0.50 [95% CI 0.42 to 0.58] and 0.63 [95% CI 0.57 to 0.69], respectively) and moderate versus severe injury during the 1-year follow-up (AUC 0.61 [95% CI 0.51 to 0.71] versus 0.64 [95% CI 0.64 to 0.74], respectively). CONCLUSION: The psychologically based model poorly predicted subsequent injury. This study does not minimize the value of assessing the psychologic profiles of injured athletes, but rather suggests that models looking to identify injury risk should consider a multifactorial approach that also includes other nonpsychologic factors such as injury history. Future studies should refine the most important psychologic constructs that can add the most value and precision to multifactorial models aimed at identifying the risk of injury. LEVEL OF EVIDENCE: Level III, prognostic study.

Baseline clinical and MRI risk factors for hamstring reinjury showing the value of performing baseline MRI and delaying return to play: a multicentre, prospective cohort of 330 acute hamstring injuries.

OBJECTIVES: Studies identifying clinical and MRI reinjury risk factors are limited by relatively small sample sizes. This study aimed to examine the association between baseline clinical and MRI findings with the incidence of hamstring reinjuries using a large multicentre dataset. METHODS: We merged data from four prospective studies (three randomised controlled trials and one ongoing prospective case series) from Qatar and the Netherlands. Inclusion criteria included patients with MRI-confirmed acute hamstring injuries (<7 days). We performed multivariable modified Poisson regression analysis to assess the association of baseline clinical and MRI data with hamstring reinjury incidence within 2 months and 12 months of follow-up. RESULTS: 330 and 308 patients were included in 2 months (31 (9%) reinjuries) and 12 months (52 (17%) reinjuries) analyses, respectively. In the 2-month analysis, the presence of discomfort during the active knee extension test was associated with reinjury risk (adjusted risk ratio (ARR) 3.38; 95% CI 1.19 to 9.64). In the 12 months analysis, the time to return to play (RTP) (ARR 0.99; 95% CI 0.97 to 1.00), straight leg raise angle on the injured leg (ARR 0.98; 95% CI 0.96 to 1.00), the presence of discomfort during active knee extension test (ARR 2.52; 95% CI 1.10 to 5.78), the extent of oedema anteroposterior on MRI (ARR 0.74; 95% CI 0.57 to 0.96) and myotendinous junction (MTJ) involvement on MRI (ARR 3.10; 95% CI 1.39 to 6.93) were independently associated with hamstring reinjury. CONCLUSIONS: Two clinical findings (the presence of discomfort during active knee extension test, lower straight leg raise angle on the injured leg), two MRI findings (less anteroposterior oedema, MTJ involvement) and shorter time to RTP were independently associated with increased hamstring reinjury risk. These findings may assist the clinician to identify patients at increased reinjury risk following acute hamstring injury. TRIAL REGISTRATION NUMBERS: NCT01812564; NCT02104258; NL2643; NL55671.018.16.

Functional Return-to-Sport Testing Demonstrates Inconsistency in Predicting Short-Term Outcomes Following Anterior Cruciate Ligament Reconstruction: A Systematic Review.

PURPOSE: To systematically review the relationship between functional testing at the time of return to sport (RTS) and short-term outcomes, such as second anterior cruciate ligament (ACL) tear and return to a preinjury level of sport, among athletes who underwent anterior cruciate ligament reconstruction (ACLR). METHODS: A systematic literature search was performed in MEDLINE, EMBASE, Scopus, and Web of Science to identify studies examining athletes who underwent functional RTS testing and were followed for at least 12 months following ACLR. Studies were screened by 2 reviewers. A standardized template was used to extract information regarding study characteristics, ACLR information, functional test results, and risk factors associated with retear or reduced RTS. RESULTS: Of the 937 studies identified, 22 met the inclusion criteria. The average time between ACLR and RTS testing was 8.5 months. Single leg hop for distance performance had no association with retear risk in any study and no association with RTS rates in most studies. Quadriceps strength had conflicting results in relation to retear risk, whereas it had no relationship with RTS rates. Rates of reinjury and RTS were similar between patients who passed and did not pass combined hop and strength batteries. Asymmetric knee extension and hip moments, along with increased knee valgus and knee flexion angles, demonstrated increased risk of retear. CONCLUSIONS: Individual hop and strength tests that are often used in RTS protocols following ACLR may have limited and inconsistent value in predicting ACL reinjury and reduced RTS when used in isolation. Combined hop and strength test batteries also demonstrate low sensitivity and negative predictive value, highlighting conflicting evidence to suggest RTS testing algorithm superiority. LEVEL OF EVIDENCE: Level IV, systematic review of Level I-IV studies.

Return to the Pre-Injury Level of Sport after Anterior Cruciate Ligament Reconstruction: A Practical Review with Medical Recommendations.

Returning to sport after anterior cruciate ligament reconstruction (ACLR) can be a challenging and complex process for the athlete, with the rate of return to the pre-injury level of sport observed to be less than athlete expectations. Of the athletes that do return to sport (RTS), knee re-injury rates remain high, and multiple studies have observed impaired athletic performance upon RTS after ACLR as well as reduced playing time, productivity, and career lengths. To mitigate re-injury and improve RTS outcomes, multiple RTS after ACLR consensus statements/clinical practice guidelines have recommended objective RTS testing criteria to be met prior to medical clearance for unrestricted sports participation. While the achievement of RTS testing criteria can improve RTS rates after ACLR, current criteria do not appear valid for predicting safe RTS. Therefore, there is a need to review the various factors related to the successful return to the pre-injury level of sport after ACLR, clarify the utility of objective performance testing and RTS criteria, further discuss safe RTS decision-making as well as present strategies to reduce the risk of ACL injury/re-injury upon RTS. This article provides a practical review of the current RTS after ACLR literature, as well as makes medical recommendations for rehabilitation and RTS decision-making after ACLR.

Reasons for Not Returning to Pre-injury Sport Level After ACL-Reconstruction.

The study aimed to identify athlete-reported reasons for not returning to pre-injury sports level after anterior cruciate ligament reconstruction (ACLR) and to identify the factors associated with these reasons. Ninety-one athletes with 2 years post-ACLR indicated whether or not they had returned to their pre-injury sport level (same frequency, duration, and intensity). Athletes who did not return were asked to provide the reasons. Athletes' characteristics and injury-related factors were used to determine factors associated with the reasons for not returning. Only nine athletes (10%) returned to pre-injury sport level after ACLR. The most common reasons for not returning were lack of confidence or concerns about re-injury (48.8%), followed by continued post-surgical impairments in the reconstructed knee (39%). Having episodes of the knee giving way after ACLR was the only significant predictor of post-surgical impairments (48.8%; OR=8.3, 95%CI=2.48-27.42, p=0.001). Lack of confidence, concerns about re-injury, or post-surgical impairments in the reconstructed knee were the most frequently reported reasons for not returning to pre-injury sports level with 2 years post-ACLR. Reported dynamic knee instability was the only factor associated with ongoing post-surgical knee impairments after ACLR. Rehabilitation programs should address athletes' psychological responses and resolve knee impairments to optimize return to pre-injury sport level after ACLR.

Global knee function rating more strongly influences adolescent athletes that sustain a sports-related surgical ACL re-injury or contralateral ACL injury.

PURPOSE: This study evaluated differences between adolescent athletes who sustained a surgical anterior cruciate ligament (ACL) re-injury, or contralateral ACL injury following return to sports bridge programme participation (Group 1) compared to those that did not (Group 2). METHODS: At 19.9 ± 7 years of age, 198 athletes participated in this study. Groups were compared for time postsurgery, preprogramme and postprogramme Knee Outcome Survey Sports Activity Scale (KOS-SAS) and global rating of knee function (GRKF) during sports activities, postprogramme lower extremity physical function test performance and perceived sports performance compared to preinjury level. RESULTS: By 6.0 ± 3.2 years postsurgery, 11 (5.6%) sustained another ACL injury. Group 1 was younger (17.3 ± 1.7 years vs. 20.1 ± 6.8 years, p < 0.001). Postprogramme re-evaluation revealed that Group 1 had a greater GRKF compared to their programme initiation GRKF than Group 2 (32.6 ± 38 vs. 20.0 ± 23, p = 0.04). Group 1 also had a greater mean preprogramme to postprogramme GRKF change than Group 2 (51.3 ± 31 vs. 35.5 ± 21, p = 0.02) (effect size = 0.73). More Group 1 subjects also had a GRKF difference that exceeded the overall mean than Group 2 (p = 0.04). Group 1 had moderately strong relationships between preprogramme and postprogramme GRKF score change and the postprogramme GRKF score (r = 0.65, p = 0.04) and between preprogramme and postprogramme KOS-SAS score change and postprogramme GRKF score (r = 0.60, p = 0.04). CONCLUSION: Global rating scores had a stronger influence among adolescent athletes that sustained either surgical ACL re-injury or contralateral ACL injury. Since group physical function and neuromuscular control factors were similar, clinicians need to increase their awareness and understanding of other factors that may influence surgical ACL re-injury or contralateral ACL injury risk. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Increased kinesiophobia leads to lower return to sport rate and clinical outcomes following osteochondral allograft transplantation of the knee.

PURPOSE: The purpose of this study is to describe the postoperative psychological state of patients following osteochondral allograft (OCA) transplantation in the knee and to determine whether patient-perceived kinesiophobia is associated with the rate of return to sport (RTS). METHODS: A retrospective review of the electronic medical record at a single institution was conducted for all patients that underwent OCA transplantation from January 2010 to 2020. Patient-reported outcomes including the visual analog scale (VAS), knee injury and osteoarthritis outcome score (KOOS) and the Tampa scale of kinesiophobia-11 (TSK-11) were collected. Patients were surveyed regarding their postoperative RTS status. RESULTS: A total of 38 patients (52.6% female) were included in our analysis. Overall, 24 patients (63.2%) returned to sport with 12 (50%) of these patients returning at a lower level of play. When comparing patients that return to sport to those that did not, patients that return had significantly superior KOOS pain (p = 0.019) and KOOS QOL (p = 0.011). Measures of kinesiophobia (TSK-11) were significantly higher among patients that did not return to sport (p = 0.014), while satisfaction (n.s.) and pain intensity (n.s.) were comparable between groups. Logistic regression models controlling for demographic factors, VAS pain scores and lesion size showed that for every one-point increase in TSK-11 kinesiophobia score, patients were 1.33 times more likely to return to sport at a lower level (p = 0.009). For every one-point increase in TSK-11 scores KOOS QOL decreased by 2.4 points (p < 0.001). CONCLUSION: Fear of reinjury decreases the likelihood that patients will return to their preoperative level of sport after OCA transplantation. Patients that do not return to sport report significantly greater fear of reinjury and inferior clinical outcomes, despite similar levels of satisfaction and pain compared to those that return. LEVEL OF EVIDENCE: Level III.

Improved Patient-reported Outcomes in Patients Aged 16 and Younger at Two Years After Anterior Cruciate Ligament Reconstruction Despite Relatively High Rates of Reinjury and Repeat Surgery.

BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) in adolescent patients, particularly those aged 16 and under, are increasingly common procedure that lacks robust clinical and patient-reported outcome (PRO) data. The purpose of this study was to report 2-year PROs of patients receiving ACLR aged 16 or younger using the single assessment numerical evaluation (SANE) and knee injury and osteoarthritis outcome score (KOOS). Secondary aims included characterizing treatment characteristics, return to sport (RTS), and clinical outcomes. METHODS: The institutional PRO database was queried for patients receiving ACLR from 2009 to 2020. Patients aged older than 16, revision procedures, concomitant ligament repairs/reconstructions, and patients without full outcome data at 2 years were excluded. Outcomes over 2 years after ACLR included SANE, KOOS, reinjuries, reoperations, and time to RTS. RESULTS: A total of 98 patients were included with an average age of 15.0 years. Most patients were females (77.6%). Bone-tendon-bone autograft (69.4%) was the most used. Average RTS was 8.7 months (range: 4.8 to 24.0 mo), with 90% of patients eventually returning to sport. A total of 23 patients (23.5%) experienced a reinjury and 24.5% (n = 24) underwent reoperation. Timing to RTS was not associated with reinjury, but patients who returned between 9.5 and 13.7 months did not sustain reinjuries. Mean KOOS and SANE scores at 2 years were 87.1 and 89.1, respectively, with an average improvement of +18.4 and +22.9, respectively. Change in KOOS was negatively impacted by reinjury to the anterior cruciate ligament graft and reoperation (anterior cruciate ligament failure: +10.0 vs 19.3, P = 0.081, respectively; reoperation: +13.2 vs +20.1, P = 0.051, respectively), though these did not reach statistical significance. CONCLUSION: Patients experienced improved SANE and KOOS scores after ACLR. Rates of reinjury and reoperation were relatively high and negatively impacted PRO scores but were not associated with the timing of RTS. Adolescent patients should be counseled regarding the risk of subsequent ipsilateral and contralateral knee injury after ACLR. LEVEL OF EVIDENCE: Level IV-case series.

Adolescent Athletes with Stronger Athletic Identity Perceptions Have Weaker Fear Avoidance Perceptions During Musculoskeletal Injury Rehabilitation Return to Sports Preparation.

BACKGROUND: Adolescent athletes who sustain a musculoskeletal sports injury are at high re-injury risk. This prospective study evaluated athletic identity perception and fear avoidance perception relationships during the return to sport preparation phase of musculoskeletal injury rehabilitation. METHODS: From 140 consecutive physical therapy outpatients, 50 (26 females, 24 males) adolescent athletes (mean age 16.8, range 14 to 22 y) completed the 7-item Athletic Identity Measurement Scale (AIMS), the 10-item Athletic Fear Avoidance Questionnaire (AFAQ), and the AFAQ with 2 additional movement-related fear and pain questions (AFAQ+). Correlational analysis was performed of overall AIMS and AIMS subscale scores (social identity, exclusivity, negative affectivity), with AFAQ and AFAQ+ scores ( P ≤0.05). RESULTS: Adolescent athletes were receiving treatment for musculoskeletal injuries sustained during soccer (n=10), lacrosse (n=7), baseball (n=6), basketball (n=5), volleyball (n=5), track or cross country (n=4), American football (n=4), field hockey or ice hockey (n=3), softball (n=2), tennis (n=2), and gymnastics (n=2). Lower extremity conditions included anterior cruciate ligament reconstruction (n=23) or other lower extremity conditions (n=17). Upper extremity conditions included shoulder dislocation or labral repair (n=6), elbow sprain or fracture (n=3), and clavicle fracture (n=1). The AIMS score displayed moderate inverse relationships with AFAQ ( r =-0.40, P =0.008) and AFAQ+ ( r =-0.41, P <0.004) scores. The "social identity" AIMS subscale score displayed a moderate inverse relationship with AFAQ ( r =- 0.48, P <0.001) and AFAQ+ ( r =-0.46, P =0.001) scores. The "exclusivity" AIMS subscale score displayed moderate inverse relationships with AFAQ ( r =-0.40, P =0.005) and AFAQ+ ( r =-0.46, P =0.001) scores. The "negative affectivity" subscale did not display significant relationships with AFAQ or AFAQ+ scores. Subject age displayed moderate inverse relationships with the AIMS "social identity" ( r =-0.56, P <0.001) and "exclusivity" ( r =-0.42, P =0.004) subscale scores and weak direct relationships with AFAQ (r=0.30, P =0.04) and AFAQ+ (r=0.32, P =0.02) scores. CONCLUSION: Adolescent athletes with stronger athletic identity perceptions during the return to the sports preparation phase of musculoskeletal injury rehabilitation had weaker fear avoidance perceptions. As age increased from early to late adolescence, athletic identity perceptions became weaker, and fear avoidance perceptions became stronger. To decrease re-injury rates, early identification and surveillance of injured adolescent athletes with stronger, more exclusive athletic identity perceptions and weaker fear avoidance perceptions may influence rehabilitation progression and return to play decisions. LEVEL OF EVIDENCE: Level-II, prospective cohort, correlational study.

Risk of Injury-Related Readmission Varies by Initial Presenting-Hospital Type Among Children at High Risk for Physical Abuse.

OBJECTIVES: Children experiencing physical abuse may initially present to hospitals with underappreciated minor injuries, only to experience more severe injuries in the future. The objectives of this study were to 1) describe young children presenting with high-risk diagnoses for physical abuse, 2) characterize the hospitals to which they initially presented, and 3) evaluate associations of initial presenting-hospital type with subsequent admission for injury. METHODS: Patients aged younger than 6 years from the 2009-2014 Florida Agency for Healthcare Administration database with high-risk diagnoses (codes previously associated with >70% risk of child physical abuse) were included. Patients were categorized by the hospital type to which they initially presented: community hospital, adult/combined trauma center, or pediatric trauma center. Primary outcome was subsequent injury-related hospital admission within 1 year. Association of initial presenting-hospital type with outcome was evaluated with multivariable logistic regression, adjusting for demographics, socioeconomic status, preexisting comorbidities, and injury severity. RESULTS: A total of 8626 high-risk children met inclusion criteria. Sixty-eight percent of high-risk children initially presented to community hospitals. At 1 year, 3% of high-risk children had experienced subsequent injury-related admission. On multivariable analysis, initial presentation to a community hospital was associated with higher risk of subsequent injury-related admission (odds ratio, 4.03 vs level 1/pediatric trauma center; 95% confidence interval, 1.83-8.86). Initial presentation to a level 2 adult or combined adult/pediatric trauma center was also associated with higher risk for subsequent injury-related admission (odds ratio, 3.19; 95% confidence interval, 1.40-7.27). CONCLUSIONS: Most children at high risk for physical abuse initially present to community hospitals, not dedicated trauma centers. Children initially evaluated in high-level pediatric trauma centers had lower risk of subsequent injury-related admission. This unexplained variability suggests stronger collaboration is needed between community hospitals and regional pediatric trauma centers at the time of initial presentation to recognize and protect vulnerable children.

Risk factors of knee reinjury after anterior cruciate ligament reconstruction.

PURPOSE: This study aimed to investigate whether the return to level I sports, concomitant injuries, foot-related problems, and other factors would increase the risk of knee reinjury after anterior cruciate ligament reconstruction (ACLR). METHODS: This study used a prospective cohort study design. Online enrolment from August 2018 to January 2019 in ACL Community Indonesia recruited 148 patients who had undergone ACLR less than one month prior to injury. Knee injury occurrence after ACLR was diagnosed through a physical examination and positive MRI or arthroscopic findings. RESULTS: During the study, 55 knee reinjuries occurred. The proportional hazards model analysis revealed that the risk of knee reinjury at 12 and 24 months for patients who returned to level I sports (hazards ratio (HR)=3.17 and HR=3.90, respectively) was significantly higher than that of the patients who did not return to sports and that the risk for those who returned to level II/III sports did not significantly increase at 12 or 24 months. Patients with concomitant meniscus injury had a significantly higher risk of knee reinjury at 12 and 24 months (HR=3.33 and HR=2.25, respectively) than those without, and the risk of knee reinjury for patients with concomitant posterior cruciate ligament injury was significantly higher at 12 months (HR=3.05) but not at 24 months. Fewer knee symptoms after ACLR were significantly associated with a lower risk of knee reinjury (HR=0.98) at 12 and 24 months. CONCLUSIONS: The return to level I sports, concomitant meniscus and posterior cruciate ligament injury, and knee symptoms after ACLR may increase the risk of knee reinjury for post-ACLR patients.

Preoperative Rehabilitation Enhances Mental and Physical Well-Being in Anterior Cruciate Ligament-Injured Individuals: A Mixed Methods Study.

CONTEXT: Rehabilitation after an anterior cruciate ligament injury is recommended to be started soon after the injury. When surgery is required, research supports the delivery of physiotherapy before anterior cruciate ligament reconstruction (prehabilitation) to optimize recovery and positive outcomes. Individuals attending prehabilitation have never been questioned regarding their adherence to prehabilitation, perception of utility in meeting needs, upcoming events, or anticipated recovery goals. DESIGN: Mixed methods cross-sectional study: Methods: 25 individuals before anterior cruciate ligament reconstruction (43% of eligible individuals from 12 clinics during the delivery period) were surveyed on their mindset and recovery expectancies. Semistructured interviews conducted in 9 of 25 participants assessed their lived experience of prehabilitation. RESULTS: Participants reported that preventing a reinjury (96% of responses) and feeling confident during daily activities about their knee (92%) were the higher rating expectations at this stage of their treatment course. Three themes were developed from the interviews and analyses. (1) Participants reported that prehabilitation was a period full of challenges with memories of the injury and uncertainties. (2) They viewed prehabilitation as a step to move forward by finding support and self-motivating. (3) They believed that prehabilitation would have positive impacts on the treatment outcomes. Participants were confident that prehabilitation would accelerate the recovery of muscle volume (88%) and strength (84%). CONCLUSION: Participants had positive experiences of prehabilitation, aligning with the findings on functional outcomes in the existing literature on prehabilitation.

Microglial phagocytosis mediates long-term restructuring of spinal GABAergic circuits following early life injury.

Peripheral injury during the early postnatal period alters the somatosensory system, leading to behavioural hyperalgesia upon re-injury in adulthood. Spinal microglia have been implicated as the cellular mediators of this phenomenon, but the mechanism is unclear. We hypothesised that neonatal injury (1) alters microglial phagocytosis of synapses in the dorsal horn leading to long-term structural changes in neurons, and/or (2) trains microglia, leading to a stronger microglial response after re-injury in adulthood. Using hindpaw surgical incision as a model we showed that microglial density and phagocytosis increased in the dorsal horn region innervated by the hindpaw. Dorsal horn microglia increased engulfment of synapses following injury, with a preference for those expressing the vesicular GABA transporter VGAT and primary afferent A-fibre terminals in neonates. This led to a long-term reduction of VGAT density in the dorsal horn and reduced microglial phagocytosis of VGLUT2 terminals. We also saw an increase in apoptosis following neonatal injury, which was not limited to the dorsal horn suggesting that larger circuit wide changes are happening. In adults, hindpaw incision increased microglial engulfment of predominantly VGAT synapses but did not alter the engulfment of A-fibres. This engulfment was not affected by prior neonatal injury, suggesting that microglial phagocytosis was not trained. These results highlight microglial phagocytosis in the dorsal horn as an important physiological response towards peripheral injury with potential long-term consequences and reveals differences in microglial responses between neonates and adults.

Differences in Risks for Recurrent Injury and Death Among Survivors of Violence by Homeless Status.

A better understanding of the unique risks for survivors of violence experiencing homelessness could enable more effective intervention methods. The aim of this study was to quantify the risks of death and reinjury for unhoused compared to housed survivors of violent injuries. This retrospective study included a cohort of patients with known housing status presenting to the Boston Medical Center Emergency Department between 2009 and 2018 with a violent penetrating injury. Cox proportional hazards regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for the risks of all-cause mortality and violent reinjury. Of the 2330 patients included for analysis, 415 (17.8%) were unhoused at the time of index injury. Within 3 years of the index injury, there were 319 (13.9%) violent reinjuries and 55 (2.4%) deaths. Unhoused patients were more likely than housed patients to be violently reinjured by all causes (HR = 1.39, 95% CI = 1.06-1.83, p = 0.02), by stab wound (HR = 2.34, 95% CI = 1.33-4.11, p = 0.0003), and by blunt assault (HR = 1.52, 95% CI = 1.05-2.21, p = 0.03). Housed and unhoused patients were equally likely to die within 3 years of their index injury; however, unhoused patients were at greater risk of dying by homicide (HR = 2.89, 95% CI = 1.34-6.25, p = 0.006) or by a drug/alcohol overdose (HR = 2.86, 95% CI = 1.17-6.94, p = 0.02). In addition to the already high risks that all survivors of violence have for recurrent injuries, unhoused survivors of violence are at even greater risk for violent reinjury and death and fatal drug/alcohol overdose. Securing stable housing for survivors of violence experiencing homelessness, and connecting them with addiction treatment, is essential for mitigating these risks.

Imaging Findings on Head Computed Tomography Scans in Victims of Intimate Partner Violence.

OBJECTIVE: The aim of the study is to analyze the imaging findings and injury patterns seen on head computed tomography (CT) examinations performed on survivors of intimate partner violence (IPV). METHODS: An institutional review board-approved retrospective analysis of 668 patients reporting IPV to our institution's violence intervention and prevention program between January 2013 and June 2018 identified 40 unique patients with radiological findings visible on head CT. All injuries visible on head CT were analyzed based on the anatomic location and injury type. Demographics, IPV screening at the time of injury, concomitant, prior, and subsequent injuries to the index head injury were also recorded. RESULTS: Our study cohort had 36 women and 4 men with a mean age at presentation of 43 ± 13 years (mean ± SD), 91 unique injuries with 57 (62.6%) isolated soft tissue injuries, 4 (3.2%) fractures, 13 (14.3%) intra-axial, and 17 (18.7%) extra-axial injuries. Soft tissue injuries and intra-axial injuries occurred most commonly in the frontal region (45.6% and 38.5%), followed by the parietal region (22.8% and 23.1%), while most extra-axial injuries were subdural hematomas (41.2%). Left-sided injuries accounted for 49% (45/91) with 29/91 right-sided (32%) and 17/91 bilateral (19%) injuries. The IPV screening occurred in 44% of injury visits (22/50). Concomitant injuries were seen in 14/50 injury visits (28%), most commonly being in the lower extremity (6/14, 42.9% [% of visits with concomitant injuries]) followed by the upper extremity (5/14, 35.7%), while 52% of visits (26/50) were preceded by prior injuries and 68% of events (34/50) were followed by subsequent injuries. CONCLUSIONS: Isolated soft tissue swelling is the most common manifestation of IPV on head CT scans with frontoparietal region being the most common site. Synchronous and metachronous injuries are frequent.