Quantitative pupillometry as a biomarker for prediction of return to play in mild traumatic brain injury: a Military Traumatic Brain Injury Initiative study.

OBJECTIVE: This study aimed to determine the validity of quantitative pupillometry to predict the length of time for return to full activity/duty after a mild traumatic brain injury (mTBI) in a cohort of injured cadets at West Point. METHODS: Each subject received baseline (T0) quantitative pupillometry, in addition to evaluation with the Balance Error Scoring System (BESS), Standardized Assessment of Concussion (SAC), and Sport Concussion Assessment Tool 5th Edition Symptom Survey (SCAT5). Repeat assessments using the same parameters were conducted within 48 hours of injury (T1), at the beginning of progressive return to activity (T2), and at the completion of progressive return to activity protocols (T3). Pupillary metrics were compared on the basis of length of time to return to full play/duty and the clinical scores. RESULTS: The authors' statistical analyses found correlations between pupillometry measures at T1, including end-initial diameter and maximum constriction velocity, with larger change and faster constriction predicting earlier return to play. There was also an association with maximum constriction velocity at baseline (T0), predicting faster return to play. CONCLUSIONS: The authors conclude that that pupillometry may be a valuable tool for assessing time to return to duty from mTBI by providing a measure of baseline resiliency to mTBI and/or autonomic dysfunction in the acute phase after mTBI.

Revision Arthroscopic Bankart Repair Results in High Failure Rates and a Low Return to Duty Rate Without Recurrent Instability.

PURPOSE: The purpose of this study was to determine, in a military population without critical bone loss, the rate of recurrent instability after revision arthroscopic stabilization for failed primary arthroscopic Bankart repair. METHODS: Forty-one revision arthroscopic stabilizations were performed at a single military institution between 2005 to 2016 for recurrent anterior shoulder instability after primary arthroscopic Bankart repair. Minimum follow-up was 2 years, and shoulders with glenoid bone loss >20% were excluded. The primary outcome of interest was the incidence of failure, defined by recurrent instability. RESULTS: Age at revision surgery averaged 22.9 ± 4.3 years, and 88% were either service academy cadets or active duty combat arms soldiers. Mean follow-up was 7.8 years. Twenty-three patients (56%) returned to duty without recurrent instability after revision arthroscopic stabilization. Eighteen patients (44%) experienced recurrent instability after return to duty. Glenoid bone loss averaged 6.2% (95% confidence interval [CI], 3.2%-9.2%) in the successful group and 5.7% (95% CI, 3.1%-8.3%) in the failure group (P = .808). CONCLUSIONS: Revision arthroscopic stabilization of failed primary arthroscopic Bankart repair has a failure rate of 44% in a young military population. The similar amounts of bone loss between groups indicates that bone loss is not the primary determinant of failure in revision arthroscopic stabilization. LEVEL OF EVIDENCE: IV, Case Series.

Association of Dynamic Knee Valgus and Bone Stress Injury in US Military Academy Cadets.

CONTEXT: Early identification of incoming military personnel at elevated odds for bone stress injury (BSI) is important for the health and readiness of the US military. DESIGN: Prospective cohort study. METHODS: Knee kinematic data of the incoming US Military Academy cadets were collected while performing a jump-landing task (The Landing Error Scoring System) using a markerless motion capture system and depth camera. Data on incidence of lower-extremity injury, including BSI, were collected throughout the study period. RESULTS: A total of 1905 participants (452 females, 23.7%) were examined for knee valgus and BSI status. A total of 50 BSI occurred during the study period (incidence proportion = 2.6%). The unadjusted odds ratio for BSI at initial contact was 1.03 (95% confidence interval [CI], 0.94-1.14; P = .49). Adjusted for sex, the odds ratio for BSI at initial contact was 0.97 (95% CI, 0.87-1.06; P = .47). At the instant of maximum knee-flexion angle, the unadjusted odds ratio was 1.06 (95% CI, 1.02-1.10; P = .01), and the odds ratio was 1.02 (95% CI, 0.98-1.07; P = .29) after adjusting for sex. This suggests that there was not a significant enough association for an increase in the odds of BSI based on either degree of knee valgus. CONCLUSIONS: Our results did not demonstrate an association between knee valgus angle data during a jump-landing task and future increased odds of BSI in a military training population. Further analysis is warranted, but the results suggests the association between kinematics and BSI cannot be effectively screened by knee valgus angle data in isolation.

Association between Sensation-Seeking Behaviors and Concussion-Related Knowledge, Attitudes, Perceived Norms, and Care-Seeking Behaviors among Collegiate Student-Athletes.

There are limited data connecting personality and behavioral tendencies and traits related to concussion care-seeking/disclosure behaviors and minimal research exists surrounding the relationship between risky behaviors, sensation-seeking, and concussion-related outcomes. This study examined the association between sensation-seeking and a student-athlete's concussion-related knowledge, attitudes, perceived social norms, and concussion care-seeking/disclosure behaviors (intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury). The current study utilized a retrospective cohort of collegiate student-athletes at a single National Collegiate Athletic Association Division I institution. Separate multivariable linear regression models estimating mean differences (MD) and 95% Confidence Intervals (CI) estimated the association between sensation-seeking and concussion knowledge, concussion attitudes, and perceived social norms. Separate multivariable binomial regression models estimating adjusted prevalence ratios (PR) and 95%CI estimated the association between sensation-seeking and intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury. All models were adjusted for sex, sport participation, and concussion history. Higher sensation-seeking was significantly associated with less favorable concussion attitudes (adjusted MD = -1.93; 95%CI = -3.04,-0.83), less favorable perceived social norms surrounding concussion (adjusted MD = -1.39; 95%CI = -2.06,-0.72), and continuing to play while experiencing concussion symptoms (adjusted PR = 1.50; 95%CI = 1.10, 2.06). Student-athletes with increased sensation-seeking could be at risk for failing to disclose a concussion, decreasing athlete safety and resulting in less optimal care post-injury. Results will inform future theory-based concussion education programs which consider behavioral tendencies and traits as well as sport culture to promote concussion care-seeking/disclosure and individualized interventions based on risky behavior engagement.

Test-Retest Reliability of Concussion Baseline Assessments in United States Service Academy Cadets: A Report from the National Collegiate Athletic Association (NCAA)-Department of Defense (DoD) CARE Consortium.

OBJECTIVE: In response to advancing clinical practice guidelines regarding concussion management, service members, like athletes, complete a baseline assessment prior to participating in high-risk activities. While several studies have established test stability in athletes, no investigation to date has examined the stability of baseline assessment scores in military cadets. The objective of this study was to assess the test-retest reliability of a baseline concussion test battery in cadets at U.S. Service Academies. METHODS: All cadets participating in the Concussion Assessment, Research, and Education (CARE) Consortium investigation completed a standard baseline battery that included memory, balance, symptom, and neurocognitive assessments. Annual baseline testing was completed during the first 3 years of the study. A two-way mixed-model analysis of variance (intraclass correlation coefficent (ICC)3,1) and Kappa statistics were used to assess the stability of the metrics at 1-year and 2-year time intervals. RESULTS: ICC values for the 1-year test interval ranged from 0.28 to 0.67 and from 0.15 to 0.57 for the 2-year interval. Kappa values ranged from 0.16 to 0.21 for the 1-year interval and from 0.29 to 0.31 for the 2-year test interval. Across all measures, the observed effects were small, ranging from 0.01 to 0.44. CONCLUSIONS: This investigation noted less than optimal reliability for the most common concussion baseline assessments. While none of the assessments met or exceeded the accepted clinical threshold, the effect sizes were relatively small suggesting an overlap in performance from year-to-year. As such, baseline assessments beyond the initial evaluation in cadets are not essential but could aid concussion diagnosis.

Reference Values for the Headache Impact Test-6 Questionnaire.

OBJECTIVE: To determine reference values for the Headache Impact Test-6 (HIT-6) in a young, physically active cohort and to examine the influence of sex, concussion history, headache history, and competitive sport level on HIT-6 scores. DESIGN: Cross-sectional. SETTING: United States Service Academy. PARTICIPANTS: United States Service Academy cadets (N=2678) completed an HIT-6 questionnaire as part of their annual concussion baseline assessment. Cadets with a recent concussion were excluded from baseline testing. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Reference values were calculated and stratified by sex, concussion history, headache history, and competitive sport level. Mann-Whitney U and Kruskal-Wallis tests were used to examine the effect of sex, concussion history, headache history, and competitive sport level on HIT-6 scores (P<.05). RESULTS: Of the 3599 cadets baselined, 2687 cadets (23% female) agreed to participate in the study and completed the HIT-6. Female participants reported significantly worse HIT-6 scores compared with male participants both with (P<.001) and without (P<.001) a concussion history. In both sexes, participants with a headache history reported worse scores than those with no headache/concussion history and a concussion history (all P<.005). Female cadets who participated in intramural athletics reported worse HIT-6 scores at baseline than female intercollegiate athletes (P=.003). CONCLUSIONS: This is the first study to stratify HIT-6 data by sex, concussion history, headache history, and sport level in a collegiate population at risk for concussions. Sex and headache history appear to influence HIT-6 scores and should be given special consideration when interpreting health-related quality of life deficits due to headache.

Recurrent Instability and Surgery Are Common After Nonoperative Treatment of Posterior Glenohumeral Instability in NCAA Division I FBS Football Players.

BACKGROUND: In-season return to play after anterior glenohumeral instability is associated with high rates of recurrent instability and the need for surgical stabilization. We are not aware of previous studies that have investigated in-season return to play after posterior glenohumeral instability; furthermore, as posterior shoulder instability in collision athletes occurs frequently, understanding the expected outcome of in-season athletes may improve the ability of physicians to provide athletes with a better understanding of the expected outcome of their injury and their ability to return to sport. QUESTIONS/PURPOSES: (1) What proportion of athletes returned to play during the season after posterior instability in collegiate football players? (2) How much time did athletes lose to injury, what proportion of athletes opted to undergo surgery, and what proportion of athletes experienced recurrent instability after a posterior instability episode during a collegiate football season? METHODS: A multicenter, prospective, observational study of National Collegiate Athletic Association (NCAA) Division 1 Football Bowl Subdivision athletes was performed at three US Military Service Academies. Ten athletes who sustained a posterior instability event during the regular football season and who pursued a course of nonoperative treatment were identified and prospectively observed through the subsequent season. All athletes in the observed cohort attempted an initial course of nonoperative treatment during the season. All athletes sustained subluxation events initially identified through history and physical examination at the time of injury. None of the athletes sustained a dislocation event requiring a manual reduction. Intraarticular pathology consisting of posterior labral pathology was further subsequently identified in all subjects via MRI arthrogram. Return to play was the primary outcome of interest. Time lost to injury, surgical intervention, and subsequent instability were secondary outcomes. RESULTS: Of the 10 athletes who opted for a trial of initial nonoperative management, seven athletes were able to return to play during the same season. Although these seven athletes returned within 1 week of their injury (median of 1 day), 5 of 7 athletes sustained recurrent subluxation events with a median (range) of four subluxation events per athlete (0 to 8) during the remainder of the season. Seven athletes were treated surgically after the completion of their season, four of whom returned to football. CONCLUSION: This study suggests that although collegiate football players are able to return to in-season sport after a posterior glenohumeral instability event, they will likely sustain multiple recurrent instability events and undergo surgery after the season is completed. The results of this study can help guide in-season management of posterior shoulder instability by allowing more appropriate postinjury counseling and decision making through the identification of those athletes who may require additional attention from medical staff during the season and possible modifications to training regimens to minimize long-term disability. Further prospective studies involving a larger cohort over several seasons should be performed through collaborative studies across the NCAA that better assess function and injury risk factors before beginning collegiate athletics. This would better characterize the natural history and associated functional limitations that athletes may encounter during their collegiate careers. LEVEL OF EVIDENCE: Level IV, prognostic study.

Gender-Specific Risk Factor Profiles for Patellofemoral Pain.

OBJECTIVE: To determine the association between selected biomechanical variables and risk of patellofemoral pain (PFP) in males and females. DESIGN: Prospective cohort. SETTING: US Service Academies. PARTICIPANTS: Four thousand five hundred forty-three cadets (1727 females and 2816 males). ASSESSMENT OF RISK FACTORS: Three-dimensional biomechanics during a jump-landing task, lower-extremity strength, Q-angle, and navicular drop. MAIN OUTCOME MEASURES: Cadets were monitored for diagnosis of PFP during their enrollment in a service academy. Three-dimensional hip and knee kinematic data were determined at initial contact (IC) and at 50% of the stance phase of the jump-landing task. Logistic regression analyses were performed for each risk factor variable in males and females (P < 0.05). RESULTS: Less than 10 degrees of hip abduction at IC [odds ratio (OR) = 1.86, P = 0.03] and greater than 10 degrees of knee internal rotation at 50% of the stance phase (OR = 1.71, P = 0.02) increased the risk of PFP in females. Greater than 20 degrees of knee flexion at IC (OR = 0.47, P < 0.01) and between 0 and 5 degrees of hip external rotation at 50% of the stance phase (OR = 0.52, P = 0.04) decreased the risk of PFP in males. No other variables were associated with risk of developing PFP (P > 0.05). CONCLUSIONS: The results suggest males and females have differing kinematic risk factor profiles for the development of PFP. CLINICAL RELEVANCE: To most effectively reduce the risk of developing PFP, the risk factor variables specific to males (decreased knee flexion and increased hip external rotation) and females (decreased hip abduction and increased knee internal rotation) should be addressed in injury prevention programs.

Measurement of the coracohumeral distance on magnetic resonance imaging in a large patient cohort.

BACKGROUND: Coracoid impingement syndrome is an increasingly recognized etiology of anterior shoulder pain. Numerus studies have documented the coracohumeral distance (CHD) as a primary or secondary measurement in symptomatic individuals, but there lacks an evaluation of CHD in a large cohort of asymptomatic individuals. The purpose of this study was to quantify a normative distribution of the CHD in a large cohort of healthy, asymptomatic subjects with no history of impingement or shoulder instability. METHODS: Incoming first-year students in the United States Military Academy were offered enrollment in this study as part of a prospective cohort to assess the normal anatomic relationships of the shoulder girdle. Magnetic resonance images were obtained, and a board-certified, fellowship-trained musculoskeletal radiologist performed measurements of the smallest distance from the coracoid to the humeral head on axial images. RESULTS: Magnetic resonance images of 714 subjects were available for analysis, including 630 males and 84 females, with a total of 1120 individual shoulders with images of adequate quality. The mean CHD for all shoulders imaged was 13.7 mm. The mean CHD in male shoulders was 13.8 mm, and in female subjects the average was 12.4 mm. CONCLUSIONS: This study is the largest of its kind to evaluate the CHD in asymptomatic, healthy shoulders to date and demonstrates a mean CHD of 13.7 mm for all subjects. This information can help to standardize "normal" ranges and act as a comparison for future work, when taken in the context of age and imaging in neutral rotation.

Perceived social norms and concussion-disclosure behaviours among first-year NCAA student-athletes: implications for concussion prevention and education.

Timely disclosure and identification of concussion symptoms are essential to proper care. Perceived social norms are a potential driving factor in many health-related decisions. The study purpose was to describe concussion disclosure behaviours and identify the association between perceived social norms and these disclosure behaviours. First-year student-athletes (n = 391) at two NCAA institutions completed a cross-sectional survey about concussion disclosure and disclosure determinants. Log-binomial regression models identified factors associated with concussion disclosure behaviour prevalence for: higher intention to disclose symptoms, disclosed all at time of injury, eventually disclosed all, and never participated with concussion symptoms. More favourable perceived social norms were associated with higher prevalence of intention to disclose (PR = 1.34; 95%CI: 1.18, 1.53) and higher prevalence of never participating in sports with concussion symptoms (PR = 1.50; 95%CI: 1.07, 2.10). Clinicians, coaches, sports administrators, and healthcare practitioners should be mindful of the need to create supportive social environments to improve concussion symptom disclosure.

Control-Normalized Fisher Ratio Analysis of Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry Data for Enhanced Biomarker Discovery in a Metabolomic Study of Orthopedic Knee-Ligament Injury.

An innovative form of Fisher ratio (F-ratio) analysis (FRA) is developed for use with comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC-TOFMS) data and applied to the investigation of the changes in the metabolome in human plasma for patients with injury to their anterior cruciate ligament (ACL). Specifically, FRA provides a supervised discovery of metabolites that express a statistically significant variance in a two-sample class comparison: patients and healthy controls. The standard F-ratio utilizes the between-class variance relative to the pooled within-class variance. Because standard FRA is adversely impacted by metabolites expressed with a large within-class variance in the patient class, "control-normalized FRA" has been developed to provide complementary information, by normalizing the between-class variance to the variance of the control class only. Thirty plasma samples from patients who recently suffered from an ACL injury, along with matched controls, were subjected to GC × GC-TOFMS analysis. Following both standard and control-normalized FRA, the concentration ratio for the top 30 "hits" in each comparison was obtained and then t-tested for statistical significance. Twenty four out of 30 metabolites plus the therapeutic agent, naproxen (24/30), passed the t-test for the control-normalized FRA, which included 8/24 unique to control-normalized FRA and 16/24 in common with the standard FRA. Likewise, standard FRA provided 21/30 metabolites passing the t-test, with 5/21 undiscovered by control-normalized FRA. The complementary information obtained by both F-ratio analyses demonstrates the general utility of the new approach for a variety of applications.

Likelihood of Return to Duty Is Low After Meniscal Allograft Transplantation in an Active-duty Military Population.

BACKGROUND: Meniscal allograft transplantation (MAT) is considered a viable surgical treatment option in the symptomatic, postmeniscectomy knee and as a concomitant procedure with ACL revision and articular cartilage repair. Although promising outcomes have recently been reported in active and athletic populations, MAT has not been well-studied in the high-demand military population. QUESTIONS/PURPOSES: (1) What proportion of active-duty military patients who underwent MAT returned to full, unrestricted duty? (2) What demographic and surgical variables, if any, correlated with return to full, unrestricted duty? METHODS: Between 2005 and 2015, three fellowship-trained sports surgeons (TMD, SJS, BDO) performed 110 MAT procedures in active-duty military patients, of which 95% (104 patients) were available for follow-up at a minimum 2 years (mean 2.8 ± SD 1.1 year). During the study period, indications for MAT generally included unicompartmental pain and swelling in a postmeniscectomized knee and as a concomitant procedure when a meniscal-deficient compartment was associated with either an ACL revision reconstruction or cartilage repair. Demographic and surgical variables were collected and analyzed. The primary endpoints were the decision for permanent profile activity restrictions and military duty termination by a medical board. The term "medical board" implies termination of military service because of medical reasons. We elected to set statistical significance at p < 0.001 to reduce the potential for spurious statistical findings in the setting of a relatively small sample size. RESULTS: Forty-six percent (48 of 104) of eligible patients had permanent profile activity restrictions and 50% (52 of 104) eventually had their military duty terminated by a military board. Only 20% (21 of 104) had neither permanent profile activity restrictions nor medical-board termination and were subsequently able to return to full duty, and only 13% (13 of 104) continued unrestricted military service beyond 2 years after surgery. Age, gender, tobacco use, and BMI did not correlate with return to full duty. Combat arms soldiers were less likely to have permanent profile activity restrictions (odds ratio 4.76 [95% confidence interval 1.93 to 11.8]; p = 0.001) and were more likely to return to full duty than soldiers in support roles (OR 0.24 [95% CI 0.09 to 0.65]; p = 0.005), although these findings did not reach statistical significance. Officers were more likely to return to full duty than enlisted soldiers at more than 2 years after surgery (OR 17.44 [95% CI 4.56 to 66.65]; p < 0.001). No surgical variables correlated with return-to-duty endpoints. CONCLUSIONS: Surgeons should be aware of the low likelihood of return to military duty at more than 2 years after MAT and counsel patients accordingly. Based on this study, MAT does not appear to be compatible with continued unrestricted military duty for most patients. LEVEL OF EVIDENCE: IV, therapeutic study.

Improving concussion education: consensus from the NCAA-Department of Defense Mind Matters Research & Education Grand Challenge.

Early disclosure of possible concussive symptoms has the potential to improve concussion-related clinical outcomes. The objective of the present consensus process was to provide useful and feasible recommendations for collegiate athletic departments and military service academy leaders about how to increase concussion symptom disclosure in their setting. Consensus was obtained using a modified Delphi process. Participants in the consensus process were grant awardees from the National Collegiate Athletic Association and Department of Defense Mind Matters Research & Education Grand Challenge and a multidisciplinary group of stakeholders from collegiate athletics and military service academies. The process included a combination of in-person meetings and anonymous online voting on iteratively modified recommendations for approaches to improve concussion symptom disclosure. Recommendations were rated in terms of their utility and feasibility in collegiate athletic and military service academy settings with a priori thresholds for retaining, discarding and revising statements. A total of 17 recommendations met thresholds for utility and feasibility and are grouped for discussion in five domains: (1) content of concussion education for athletes and military service academy cadets, (2) dissemination and implementation of concussion education for athletes and military service academy cadets, (3) other stakeholder concussion education, (4) team and unit-level processes and (5) organisational processes. Collectively, these recommendations provide a path forward for athletics departments and military service academies in terms of the behavioural health supports and institutional processes that are needed to increase early and honest disclosure of concussion symptoms and ultimately to improve clinical care outcomes.

Reference values for the Balance Error Scoring System as measured by the Tekscan MobileMat™ in a physically active population.

OBJECTIVES: The Balance Error Scoring System (BESS) is commonly used to measure postural stability; however, it has demonstrated inconsistent reliability values when administered by humans. The Tekscan MobileMat™ was developed to automate the assessment of BESS errors and eliminate rater subjectivity. The objective of this study was to report reference values for the BESS, as measured by the MobileMat™, and examine the effect of sex, concussion history, and competitive sport level on BESS performance. METHODS: Four hundred and forty participants performed the BESS on the MobileMat™. Participants were asked to maintain each stance with their eyes closed for 20 s. The MobileMat™ was used to quantify the number of errors. RESULTS: Concussion history (p = 0.279-0.979) and competitive sport level (p = 0.422-0.979) did not affect BESS performance. Males performed significantly better than females for the single-limb foam stance (p = 0.032). No sex differences were detected for the other BESS stances or BESS total score (p = 0.067-0.744). CONCLUSIONS: Previously reported reference values in collegiate athletes and adolescents were slightly higher thus highlighting the value in establishing population norms and in developing new technologies to objectively quantify BESS performance. Furthermore, sex, concussion history, and competitive sport level do not appear to influence BESS performance as measured by the MobileMat™.

Sex and number of concussions influence the association between concussion and musculoskeletal injury history in collegiate athletes.

OBJECTIVES: Examine the association between concussion and lower extremity injury in collegiate athletes and the influence of sex and the number of concussions on this relationship. METHODS: A total of 468 collegiate student-athletes (200 Males, 268 Females) were recruited from collegiate athletic facilities of three universities to participate in this retrospective review. Participants provided injury history (concussions, ankle sprains, and knee injuries) information through a survey. Chi-square tests and odds ratios examined the relationship between concussion and ankle sprain or knee injury history within each sex and based on concussion history (0, 1, >1). RESULTS: Females athletes with a concussion history had greater odds of reporting an ankle sprain or knee injury compared to females with no concussion history (OR = 1.88-2.54; p ≤ 0.020). Male athletes with a concussion history did not have greater odds of reporting an ankle sprain or knee injury. Athletes reporting multiple concussions had the greatest odds of ankle sprain or knee injury history compared to athletes with no previous concussions (OR = 2.43-2.56; p ≤ 0.004). No differences were identified between athletes with a single or multiple concussion history. CONCLUSION: Female athletes with a concussion history or participants with a multiple concussion history had the greatest odds of reporting an ankle or knee injury history compared to athletes with no concussion history.

Effect of a Lower Extremity Preventive Training Program on Physical Performance Scores in Military Recruits.

Peck, KY, DiStefano, LJ, Marshall, SW, Padua, DA, Beutler, AI, de la Motte, SJ, Frank, BS, Martinez, JC, and Cameron, KL. Effect of a lower extremity preventive training program on physical performance scores in military recruits. J Strength Cond Res 31(11): 3146-3157, 2017-Exercise-based preventive training programs are designed to improve movement patterns associated with lower extremity injury risk; however, the impact of these programs on general physical fitness has not been evaluated. The purpose of this study was to compare fitness scores between participants in a preventive training program and a control group. One thousand sixty-eight freshmen from a U.S. Service Academy were cluster-randomized into either the intervention or control group during 6 weeks of summer training. The intervention group performed a preventive training program, specifically the Dynamic Integrated Movement Enhancement (DIME), which is designed to improve lower extremity movement patterns. The control group performed the Army Preparation Drill (PD), a warm-up designed to prepare soldiers for training. Main outcome measures were the Army Physical Fitness Test (APFT) raw and scaled (for age and sex) scores. Independent t tests were used to assess between-group differences. Multivariable logistic regression models were used to control for the influence of confounding variables. Dynamic Integrated Movement Enhancement group participants completed the APFT 2-mile run 20 seconds faster compared with the PD group (p < 0.001), which corresponded with significantly higher scaled scores (p < 0.001). Army Physical Fitness Test push-up scores were significantly higher in the DIME group (p = 0.041), but there were no significant differences in APFT sit-up scores. The DIME group had significantly higher total APFT scores compared with the PD group (p < 0.001). Similar results were observed in multivariable models after controlling for sex and body mass index (BMI). Committing time to the implementation of a preventive training program does not appear to negatively affect fitness test scores.

Arthroscopic Training Courses Improve Trainee Arthroscopy Skills: A Simulation-Based Prospective Trial.

PURPOSE: To evaluate the correlation between timed task performance on an arthroscopy shoulder simulator and participation in a standardized expert shoulder arthroscopy educational course. METHODS: Orthopaedic trainees were voluntarily recruited from over 25 residency programs throughout the United States and Canada. Each trainee was tested on arrival at the Arthroscopy Association of North America orthopaedic learning center on a virtual reality arthroscopy shoulder simulator, and his or her performance was objectively scored. Each trainee's postgraduate year level was recorded, as was his or her experience in residency with shoulder arthroscopy as measured by Accreditation Council for Graduate Medical Education case-log totals. After the focused 4-day training curriculum consisting of didactics and cadaveric experience, each trainee was re-evaluated on the same simulator. Statistical analysis was performed to determine if participation in the course was associated with changes in simulation performance from before to after assessment. RESULTS: Forty-eight trainees completed the testing. On completion of the course, trainees showed significant improvements in all objective measures recorded by the simulator. Total probe distance needed to complete the task decreased by 42% (from 420.4 mm to 245.3 mm, P < .001), arthroscope tip distance traveled decreased by 59% (from 194.1 mm to 80.2 mm, P < .001), and time to completion decreased by 38% (from 66.8 seconds to 41.6 seconds, P < .001). Highly significant improvements in all 3 measures suggest improved instrument handling, anatomic recognition, and arthroscopy-related visual-spatial ability. CONCLUSIONS: This study shows objective improvement in orthopaedic trainee basic arthroscopy skill and proficiency after a standardized 4-day arthroscopy training curriculum. The results validate the Arthroscopy Association of North America resident training course and its curriculum with objective evidence of benefit. LEVEL OF EVIDENCE: Level III, prospective study of nonconsecutive participants.

Trends in the diagnosis of SLAP lesions in the US military.

PURPOSE: Shoulder pathology, particularly SLAP (superior labrum anterior-posterior) lesions, is prevalent in overhead athletes and physically active individuals. The aim of this study is to quantify the burden of SLAP lesions in the military and establish risk factors for diagnosis. METHODS: A retrospective analysis of all service members diagnosed with a SLAP lesion (International Classification of Disease, Ninth Revision code 840.70) in the Defense Medical Epidemiological Database between 2002 and 2009 was performed. Available epidemiological risk factors including age, sex, race, military rank, and branch of service were evaluated using multivariate Poisson regression analysis, and cumulative and subgroup incidence rates were calculated. RESULTS: During the study period, approximately 23,632 SLAP lesions were diagnosed among a population at risk of 11,082,738, resulting in an adjusted incidence rate of 2.13 per 1,000 person-years. The adjusted annual incidence rate for SLAP lesions increased from 0.31 cases per 1,000 person-years in 2002 to 1.88 cases per 1,000 person-years in 2009, with an average annual increase of 21.2 % (95 % CI 20.7 %, 22.0 %, p < 0.0001) during the study period. Age, sex, race, branch of military service, and military rank were independent risk factors associated with the incidence rate of SLAP lesion (p < 0.01). Male service members were over twofold more likely (IRR, 2.12; 95 % CI 2.01, 2.23) to sustain a SLAP lesion when compared with females. Increasing age category was associated with a statistically significant increase in the incidence rate for SLAP lesions in the present study (p < 0.001). After controlling for the other variables, those individuals of white race, enlisted ranks, or Marine Corps service experienced the highest incidence rates for SLAP. CONCLUSION: This is the first study to establish the epidemiology of SLAP lesions within an active military cohort in the American population. Sex, age, race, military rank, and branch of military service were all independently associated with the incidence rate of SLAP lesions in this physically active population at high risk for shoulder injury. LEVEL OF EVIDENCE: II.

Shoulder impingement in the United States military.

BACKGROUND: Little is known about the incidence and characteristics of primary, or external, shoulder impingement in an occupationally and physically active population. A longitudinal, prospective epidemiologic database was used to determine the incidence and risk factors for shoulder subacromial impingement in the United States (U.S.) military. Our hypothesis was that shoulder impingement is influenced by age, sex, race, military rank, and branch of service. METHODS: The Defense Medical Epidemiology Database was queried for all shoulder impingement injuries using International Classification of Disease, Ninth Addition, Clinical Modification code 726.10 within a 10-year period from 1999 through 2008. An overall injury incidence was calculated, and a multivariate analysis performed among demographic groups. RESULTS: In an at-risk population of 13,768,534 person-years, we identified 106,940 cases of shoulder impingement resulting in an incidence of 7.77/1000 person-years in the U.S. military. The incidence of shoulder impingement increased with age and was highest in the group aged ≥40 years (incidence rate ratio [IRR], 4.90; 95% confidence interval [CI], 4.61-5.21), was 9.5% higher among men (IRR, 1.10, 95% CI, 1.06-1.13), and compared with service members in the Navy, those in the Air Force, Army, and Marine Corps were associated with higher rates of shoulder impingement (IRR, 1.46 [95% CI, 1.42-1.50], 1.42 [95% CI, 1.39-1.46], and 1.31 [95% CI, 1.26-1.36], respectively). CONCLUSIONS: The incidence of shoulder impingement among U.S. military personnel is 7.77/1000 person-years. An age of ≥40 years was a significant independent risk factor for injury.

Outcomes after bankart repair in a military population: predictors for surgical revision and long-term disability.

PURPOSE: To quantify the rate of surgical failure after anterior shoulder stabilization procedures, as well as to identify demographic and surgical risk factors associated with poor outcomes. METHODS: All Army patients undergoing arthroscopic or open Bankart repair for shoulder instability were isolated from the Military Health System Management Analysis and Reporting Tool between 2003 and 2010. Demographic variables (age, gender) and surgical variables (treatment facility volume, admission status, surgical technique) were extracted. Rates of surgical failure, defined as subsequent revision surgery or medical discharge with persistent shoulder complaints, were recorded from the electronic medical record and US Army Physical Disability Agency database. Risk factor analysis was performed with univariate t tests, χ(2) tests, and a multivariable logistic regression model with failure as the outcome. RESULTS: A total of 3,854 patients underwent Bankart repair during the study period, with most procedures having been performed arthroscopically (n = 3,230, 84%) and on an outpatient basis (n = 3,255, 84%). Patients were predominately men (n = 3,531, 92%), and the mean age was 28.0 years (SD, 7.5 years). A total of 193 patients (5.0%) underwent revision stabilization whereas 339 patients (8.8%) were medically discharged with complaints of shoulder instability, for a total combined failure rate of 13.8% (n = 532). Univariate analyses showed no significant effect for gender; however, younger age, higher facility volume, open repair, and inpatient status were significant factors associated with subsequent surgical failure. Multivariable analyses confirmed that young age (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.91 to 0.96; P < .001), open repair (OR, 0.52; 95% CI, 0.36 to 0.75; P = .001), and inpatient status (OR, 0.58; 95% CI, 0.40 to 0.84; P = .004) were independently associated with failure by revision surgery. CONCLUSIONS: Young age remains a significant risk factor for surgical failure after Bankart repair. Patients who underwent arthroscopic Bankart repair had a significantly lower surgical failure rate (4.5%) than patients who underwent open anterior stabilization (7.7%). Despite advances in surgical technique, 1 in 20 military service members required revision surgery after failed primary stabilization in this study. LEVEL OF EVIDENCE: Level IV, therapeutic case series.