Inertial Measurement Unit-Derived Ergonomic Metrics for Assessing Arm Use in Manual Wheelchair Users With Spinal Cord Injury: A Preliminary Report.

BACKGROUND: Individuals with spinal cord injury (SCI) who use manual wheelchairs (MWCs) have a higher rate of rotator cuff pathology progression than able-bodied individuals. OBJECTIVES: This study aimed to test the ability of risk and recovery metrics of arm use to differentiate between (1) MWC users with SCI and matched able-bodied participants (cross-sectional matched-sample study) and (2) MWC users with rotator cuff pathology progression over 1 year from those without pathology progression (longitudinal study). METHODS: Thirty-four MWC users and 34 age- and sex-matched able-bodied individuals were recruited. Upper arm risk (humeral elevation >60°) and recovery (static ≥5 seconds and humeral elevation <40°) metrics were calculated from wireless inertial measurement units (IMUs) worn on the upper arms and torso in the free-living environment. Two separate magnetic resonance imaging studies were completed and assessed for a subset of 16 MWC users approximately 1 year apart. RESULTS: The frequency of risk events (p = .019), summated duration of recovery events (p = .025), and duration of each recovery event (p = .003) were higher for MWC users than able-bodied participants. The summated duration of risk events (p = .047), frequency of risk events (p = .027), and risk to recovery ratio (p = .02) were higher and the summated duration of recovery events (p = .036) and frequency of recovery events (p = .047) were lower for MWC users with rotator cuff pathology progression (n = 5) compared to those without progression (n = 11). CONCLUSION: IMU-derived metrics quantifying arm use at postures >60° and risk to recovery ratios may provide insights of potential risk factors for rotator cuff pathology progression.

Elbow Overuse Injuries in Pediatric Female Gymnastic Athletes: Comparative Findings and Outcomes in Radial Head Stress Fractures and Capitellar Osteochondritis Dissecans.

BACKGROUND: Radial head stress fractures (RHSFs) and capitellar osteochondritis dissecans (COCD) are rare but may be seen in gymnasts. The purpose of this study was to compare the clinical and radiographic characteristics and the outcomes of RHSF and COCD in pediatric and adolescent gymnastic athletes. METHODS: Classical gymnasts and competitive tumblers ≤18 years of age presenting with RHSF or COCD over a 5-year period were reviewed. Radiographic characteristics, clinical characteristics, and patient-reported outcomes were compared. RESULTS: Fifty-eight elbows (39 with COCD and 19 with RHSF) were studied; the mean patient age was 11.6 years. Gymnastic athletes with RHSF competed at a higher level; of the athletes who competed at level ≥7, the rate was 95% of elbows in the RHSF group and 67% of elbows in the COCD group. The RHSF group presented more acutely with more valgus stress pain than those with COCD (p < 0.01) and demonstrated increased mean valgus angulation (and standard deviation) of the radial neck-shaft angle (13° ± 3.8° for the RHSF group and 9.3° ± 2.8° for the COCD group; p < 0.01) and decreased mean proximal radial epiphyseal height (3.7 ± 0.6 mm for the RHSF group and 4.2 ± 1.5 mm for the COCD group; p < 0.01). At a minimum of 2 years (range, 2.0 to 6.3 years), the RHSF group reported fewer symptoms; the QuickDASH (abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire) score was 1.75 ± 3.84 points for the RHSF group and 7.45 ± 7.54 points for the COCD group (p < 0.01). Those at a high level (≥7) were more likely to return to gymnastics independent of pathology, with the RHSF group reporting higher final activity levels with the mean Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) score at 26.0 ± 7.5 points compared with the COCD group at 23.6 ± 5.7 points (p < 0.05). Of the 9 patients with bilateral COCD, only 3 (33%) returned to gymnastics. CONCLUSIONS: RHSF with features similar to the more familiar COCD lesion may present in gymnastic athletes. Those with RHSF may present more acutely with a high competitive level and may have a better prognosis for return to competitive gymnastics than those with COCD. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Lesiones deportivas por sobreuso en niños y adolescentes / Sports injuries due to overuse in children and adolescents

La actividad deportiva en niños y adolescentes ha presentado un aumento sostenido en nuestro país en los últimos años; esto ha generado un aumento de las lesiones deportivas por sobreuso. Éstas pueden tener múltiples orígenes, dependiendo de la edad y la actividad del paciente. La mayoría son de manejo conservador, sin embargo, algunas requieren manejo quirúrgico. Lo más importante es la prevención de estas lesiones mediante el uso de equipo apropiado, regulando la intensidad y tipo de entrenamiento y tratando precozmente las lesiones.

Sports activity in children and adolescents has presented a sustained increase in our country in recent years, generating an increase in sports-related overuse injuries. These injuries vary in nature, depending on the patient ́s age and level of training. Most are conservatively managed; although, some will require surgical treatment. It is important, however, to try to prevent these injuries by using appropriate equipment, regulating the intensity and type of training and treating injuries early

Evidence of Bilateral Localized, but Not Widespread, Pressure Pain Hypersensitivity in Patients With Upper Extremity Tendinopathy/Overuse Injury: A Systematic Review and Meta-Analysis.

OBJECTIVE: The presence of altered nociceptive pain processing in patients with upper extremity tendinopathy/overuse injury is conflicting. Our aim was to compare pressure pain thresholds (PPTs) in symptomatic and distant pain-free areas between patients with upper extremity tendinopathy/overuse injury and controls. METHODS: Five databases were searched from inception to October 15, 2020. The authors selected case-control studies comparing PPTs between individuals with upper extremity tendinopathy/overuse injury and pain-free controls. Data were extracted for population, diagnosis, sample size, outcome, and type of algometer. Results were extracted by 3 reviewers. The methodological quality/risk of bias (Newcastle-Ottawa Quality Assessment Scale) and evidence level (Grading of Recommendations Assessment, Development and Evaluation approach) were assessed. Meta-analyses of symptomatic, segment-related, and distant pain-free areas were compared. RESULTS: The search identified 807 publications with 19 studies (6 shoulder, 13 elbow) eligible for inclusion. The methodological quality ranged from fair (48%) to good (37%). Patients exhibited lower bilateral PPTs than controls at the symptomatic area (affected side: MD = -175.89 kPa [95% CI = -220.30 to -131.48 kPa]; nonaffected side: MD = -104.50 kPa [95% CI = -142.72 to -66.28 kPa]) and the segment-related area (affected side: MD = -150.63 kPa [95% CI = -212.05 to -89.21 kPa]; nonaffected side: MD = -170.34 kPa [95% CI = - 248.43 to -92.25]) than controls. No significant differences in PPTs over distant pain-free areas were observed. CONCLUSION: Low to moderate quality evidence suggests bilateral hypersensitivity to pressure pain at the symptomatic and contralateral/mirror areas in patients with upper extremity tendinopathies/overuse injury. Moderate quality of evidence supports bilateral pressure pain sensitivity in the segment-related area (neck) in lateral epicondylalgia, but not in subacromial impingement syndrome. No evidence of widespread pressure pain hyperalgesia was reported. IMPACT: Early identification of people with altered pain modulation could guide clinicians in treatment strategies. This review shows that there is a complex interplay between peripheral and central pain mechanisms in upper extremity tendinopathies/overuse injuries and that there likely are different subgroups of patients with upper extremity conditions.

Upper Extremity Overuse Injuries and Obesity After Spinal Cord Injury.

Persons with spinal cord injury (SCI) are at high risk for developing neurogenic obesity due to muscle paralysis and obligatory sarcopenia, sympathetic blunting, anabolic deficiency, and blunted satiety. Persons with SCI are also at high risk for shoulder, elbow, wrist, and hand injuries, including neuromusculoskeletal pathologies and nociceptive pain, as human upper extremities are poorly designed to facilitate chronic weight-bearing activities, including manual wheelchair propulsion, transfers, self-care, and day-to-day activities. This article reviews current literature on the relationship between obesity and increased body weight with upper extremity overuse injuries, detailing pathology at the shoulders, elbows, and wrists that elicit pain and functional decline and stressing the importance of weight management to preserve function.

The Effect of Straight-Line Long-Toss Versus Ultra-Long-Toss Throwing on Passive Glenohumeral Range of Motion Recovery After Pitching.

BACKGROUND: Repetitive throwing in baseball pitchers can lead to pathologic changes in shoulder anatomy, range of motion (notably glenohumeral internal rotation deficit), and subsequent injury; however, the ideal strengthening, recovery, and maintenance protocol of the throwing shoulder in baseball remains unclear. Two strategies for throwing shoulder recovery from pitching are straight-line long-toss (SLT) throwing and ultra-long-toss (ULT) throwing, although neither is preferentially supported by empirical data. HYPOTHESIS: ULT will be more effective in returning baseline internal rotation as compared with SLT in collegiate pitchers after a pitching session. STUDY DESIGN: Cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 24 National Collegiate Athletic Association Division I baseball pitchers with mean age 20.0 ± 1.1 years were randomized to either the ULT group (n = 13; 9 right-hand dominant, 4 left-hand dominant) or SLT group (n = 11; 10 right-hand dominant, 1 left-hand dominant). Measurements (dominant and nondominant, 90° abducted external rotation [ER], internal rotation [IR], and total range of motion [TROM]) were taken at 5 time points across 3 days: before and immediately after a standardized bullpen session on day 1; before and immediately after a randomized standardized ULT or SLT session on day 2; and before practice on Day 3. RESULTS: ULT demonstrated significantly greater final ER compared with baseline (+10°; P = 0.05), but did not demonstrate significant IR changes. Similarly, SLT demonstrated significantly greater post-SLT ER (+12°; P = 0.02) and TROM (+12°;P = 0.01) compared with baseline, but no significant IR changes. Final ER measurements were similar between ULT (135° ± 14°) and SLT (138° ± 10°) (P = 0.59). There was also no statistically significant difference in final IR between ULT (51° ± 14°) and SLT (56° ± 8°) (P = 0.27). CONCLUSION: The routine use of postperformance, ULT throwing to recover from range of motion alterations, specifically IR loss, after a pitching session is not superior to standard, SLT throwing. Based on these findings, the choice of postpitching recovery throwing could be player specific based on experience and comfort. CLINICAL RELEVANCE: The most effective throwing regimens for enhancing performance and reducing residual impairment are unclear, and ideal recovery and maintenance protocols are frequently debated with little supporting data. Two strategies for throwing shoulder recovery from pitching are SLT and ULT throwing. These are employed to help maintain range of motion and limit IR loss in pitchers. The routine use of ULT throwing for recovery and to limit range of motion alterations after a pitching session is not superior to SLT throwing.

Overuse injuries in runners of different abilities-a one-year prospective study.

The aim of this prospective study was to investigate differences in participant characteristics, previous injury, running dynamics during a long-distance run, and training between injured and uninjured runners in runners of different abilities. Center-of-mass acceleration data were collected during a long-distance overground run. Runners were then divided into four groups (elite, advanced, intermediate and slow) based on their finishing time. Participants completed training diaries and were monitored for 1 year. Seventy-six runners completed the prospective study with 39 (51.3%) sustaining a running injury (44% elite, 42% advanced, 54% intermediate, 59% slow). Differences between injured and uninjured runners within each group related to injury included: (1) elite injured runners ran with longer contact times and (2) more slow injured runners reported an injury in previous year, were heavier, had higher body mass and body mass index, ran with lower step frequencies, and ran a greater weekly distance. Advanced injured runners exhibited fatigue changes in step regularity and peak braking during the run that may be related to injury. These findings suggest that runners of different abilities may have different factors related to injury however due to the small sample sizes in the groups this needs to be explored further.

Running after cycling induces inter-limb differences in muscle activation but not in kinetics or kinematics.

Overuse injuries are a common problem to triathletes' population. Overuse injuries may arise from inter-limb biomechanical differences during running, but the literature lacks information regarding inter-limb differences in triathletes. In this study inter-limb differences were investigated in injury-free triathletes during the running portion of a simulated cycle-run transition. Thirteen triathletes performed a 5 km run preceded by a 20 min cycling trial at 70% of maximal power output. During the Start, Mid and End stages of running, kinetic, kinematic and muscle activation variables were compared between the preferred and non-preferred limbs across the stance phase. A statistical parametric mapping analysis showed no differences between limbs when considering kinetic and kinematic variables (p > 0.05, ES<0.60). A lower soleus activation was observed in the preferred limb (p < 0.05, ES>0.60) from 53.40-75.9% of the stance phase at the End stage of running. In conclusion, inter-limb differences in kinetic or kinematic variables may not represent a risk for overloading in triathletes. However, inter-limb differences in triceps surae activation during running after cycling may represent one potential factor leading to overuse injuries in triathletes and should be further investigated.

Segment coordination and variability among prospectively injured and uninjured runners.

Coordinative variability (CAV) and underlying coordinative patterns are potential running-related overuse injury (RROI) mechanisms, but prospective analyses are needed. This study compared lower limb CAV and coordinative patterns between prospectively injured and uninjured runners. Knee, shank, and ankle kinematics were collected for 39 recreational runners at the beginning of a 6-month follow-up period. Subjects were classified as injured (n=21) or controls (n=18) based on RROI incidence during follow-up. CAV was quantified using modified vector coding. Time spent in each coordinative pattern category was quantified using binning frequency analysis. Coordinative patterns were classified as mechanically unsound if underlying joint/segment motions opposed anatomically allowable running motion. Wilcoxon Rank-Sum tests compared CAV and binning frequencies between groups within different stance portions for knee-shank, shank-ankle, and knee-ankle couplings (α≤0.05). During initial-stance, the injured group displayed significantly greater knee-ankle CAV (effect size (ES)=1.1), knee-shank CAV (ES=0.97), and greater frequency of mechanically unsound knee-shank (ES=0.72) and shank-ankle (ES=0.63) motion. During mid-stance, the injured group displayed lower frequency of mechanically sound knee-ankle motion (ES=0.31). In late-stance, the injured group displayed greater shank-ankle CAV (ES=0.11). Mechanically unsound coordinative patterns along with greater knee-ankle and shank-ankle CAV potentially lead to RROI.

Decreased Physical Activity and Sleep, Not Sport Specialization, Predict Illness in Middle School Athletes.

BACKGROUND: The relationships between sport specialization, physical activity, sleep, and illness in younger athletes are unknown. Therefore, the purpose of this study was to evaluate the independent effects of sport specialization, sleep, and physical activity on illness in middle school athletes. HYPOTHESIS: Decreased sleep, decreased physical activity, and higher levels of sport specialization will be associated with an increased risk of illness among middle school athletes. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 4. METHODS: Parents of middle school-aged children reported baseline sport specialization (low, moderate, or high) as well as sleep duration, physical activity, and illnesses every week throughout the academic year. A mixed-effects logistic regression model was used to assess the association between illness and specialization while accounting for sleep and physical activity for the prior week as fixed effects and each individual as a random effect. RESULTS: A total of 233 children (mean age, 12.1 ± 1.2 years; 61% male) participated, of whom 41%, 25%, and 34% were categorized as low, moderate, and high specialization, respectively. The proportion of individuals who experienced illness did not differ by specialization level (low, 76%; moderate, 70%; high, 59%; P = 0.064). In the multivariable model, the odds of illness compared with the low specialization group was not significantly different for moderate (odds ratio [OR], 0.93; 95% CI, 0.70-1.23; P = 0.61) or high specialization (OR, 0.76; 95% CI, 0.56-1.03; P = 0.073). A decreased risk of illness was associated with greater prior week sleep (OR, 0.79; 95% CI, 0.69-0.91; P < 0.001) and physical activity (OR, 0.94; 95% CI, 0.92-0.96; P < 0.001). CONCLUSION: Sport specialization is not associated with an increased risk of illness among middle school athletes, while increased sleep duration and physical activity appear to reduce the risk of illness. CLINICAL RELEVANCE: Interventions to promote physical activity and improve sleep may reduce the risk of illness in early adolescent athletes.

Surgery for trapeziometacarpal osteoarthritis in relation to cumulative occupational hand force requirements: a Danish nationwide cohort study.

OBJECTIVES: To evaluate if higher cumulative occupational hand force requirements are associated with higher risks of surgery for trapeziometacarpal osteoarthritis and with surgery earlier in life. METHODS: The study was based on Danish national registers. Among all persons born in Denmark 1931 to 1990, we included those who had been employed for at least 5 years since 1991 by the end of 2000, or later when this employment criterion was reached, up until the end of 2016. Cumulative exposure estimates for 10-year time windows (force-years) were assessed by combining individual year-by-year information on occupational codes with an expert based hand-arm job exposure matrix. First-time events of surgery for trapeziometacarpal osteoarthritis 2001 to 2017 constituted the outcome. Surgery rates were analysed by a logistic regression technique equivalent to discrete survival analysis using a 1-year lag. We also calculated rate advancement periods. RESULTS: A total of 2 860 448 persons contributed with around 48 million person-years of follow-up, during which 3977 cases appeared (821 among men and 3156 among women). Compared with <5 force-years, the adjusted OR (ORadj) for ≥5 to <10 force-years was 1.39 (95% CI 1.14 to 1.68) and for ≥10 to 30 force-years 1.47 (95% CI 1.26 to 1.71) among men and 1.64 (95% CI 1.50 to 1.78) and 1.29 (95% CI 1.16 to 1.43) among women. The sex combined ORadj were 1.59 (95% CI 1.47 to 1.72) and 1.36 (95% CI 1.25 to 1.48). Among the exposed, surgery was advanced by 3 to 7 years. CONCLUSION: Medium/high cumulative hand force requirements were associated with elevated hazard rates of surgery for trapeziometacarpal osteoarthritis and advanced the time of surgery by several years.

Biomechanics of Sport-Related Neurological Injury.

As awareness on the short-term and long-term consequences of sports-related concussions and repetitive head impacts continues to grow, so too does the necessity to establish biomechanical measures of risk that inform public policy and risk mitigation strategies. A more precise exposure metric is central to establishing relationships among the traumatic experience, risk, and ultimately clinical outcomes. Accurate exposure metrics provide a means to support evidence-informed decisions accelerating public policy mandating brain trauma management through sport modification and safer play.

Similar effects of fatigue induced by a repetitive pointing task on local and remote light touch and pain perception in men and women.

BACKGROUND: Women involved in repetitive, fatiguing, jobs develop more neck and/or shoulder musculoskeletal disorders than men. Sex differences in the pain response to exercise could contribute to the higher prevalence of neck/shoulder musculoskeletal disorders in women. The objective of this study was to assess sex differences in pain sensitivity following a fatiguing upper limb task. Relationships between measures of fatigue and of the sensitivity to nociceptive and to non-nociceptive stimulations were also explored. METHODS: Thirty healthy adults (15 women) performed a fatiguing repetitive pointing task with their dominant arm. Upper limb electromyography was recorded from the dominant upper trapezius, anterior deltoid and bicep brachii and from the contralateral tibialis anterior. Before and immediately after the repetitive pointing task, pressure pain and light touch sensitivity thresholds were measured over the same muscles. RESULTS: Electromyographic signs of fatigue were observed only in the anterior deltoid and biceps brachii muscles. Pressure pain thresholds over both muscles increased slightly (effect size ≤ 0.34), but no changes occurred over the upper trapezius and the tibialis anterior. Light touch thresholds increased moderately to importantly after the repetitive pointing task over all four muscles (effect sizes = 0.58 to 0.87). No sex differences were observed in any sensory variable. Moreover, no or weak correlations (r = -0.27 to 0.39) were observed between electromyographical signs of fatigue, light touch threshold and pressure pain threshold variables. CONCLUSIONS: We observed sex-independent effects of a repetitive upper limb task on the sensitivity to painful and to nonpainful stimuli. Moreover, the hypoalgesia induced by the repetitive pointing task was weak and localized, and did not directly correlate with the induced muscle fatigue. Results suggest that fatigue-related changes in the sensitivity to noxious and innocuous stimuli could not explain women's greater prevalence of neck/shoulder musculoskeletal disorders.

Acute shoe effects on Achilles tendon loading in runners with habitual rearfoot strike pattern.

OBJECTIVES: Although the overuse injury rate of the Achilles tendon (AT) for running is high, the effect of shoe conditions on AT loading remains unclear. Hence, this study aims to determine the mechanical properties of AT during running under different shoe conditions (minimalist vs. conventional shoes). DESIGN: This work is a controlled laboratory study. METHODS: Sixteen healthy male rearfoot strike runners were recruited to complete over ground running trials at 3.33 m/s (±5%) under two shoe conditions (minimalist shoes: INOV-8 Bare-XF 210; conventional shoes: NIKE AIR ZOOM PEGASUS 34). Sagittal plane ankle kinematics and ground reaction forces were simultaneously recorded. Ankle joint mechanics (ankle joint angle and moment) and the mechanical properties (peak force, impulse, stress, strain, and their corresponding peak rate) of the AT were calculated. RESULTS: In comparison with conventional shoes, wearing minimalist shoes showed significant changes (p < 0.05): (1) decreased strike angle (48.92 ±â€¯9.01 vs. 41.04 ±â€¯8.69°); (2) increased ankle moment (2.34 ±â€¯0.44 vs. 2.55 ±â€¯0.46 Nm/kg); (3) increased peak AT force (5.85 ±â€¯1.22 vs. 6.24 ±â€¯1.13 BW), AT force impulse (0.65 ±â€¯0.13 vs. 0.70 ±â€¯0.13 BW·s), peak AT loading rate (109.94 ±â€¯9.33 vs. 118.84 ±â€¯26.62 BW/s), and average loading rate (48.42 ±â€¯15.64 vs. 54.90 ±â€¯17.47 BW/s); (4) decreased time to peak AT force (126.31 ±â€¯20.68 vs. 117.77 ±â€¯17.62 ms); (5) increased AT stress (66.96 ±â€¯14.59 vs. 71.89 ±â€¯14.74 MPa), strain (8.19 ±â€¯1.77 vs. 8.78 ±â€¯1.80 %), peak AT stress rate (66.96 ±â€¯14.59 vs. 71.89 ±â€¯14.74 MPa/s), and strain rate (148.71 ±â€¯48.52 vs. 167.28 ±â€¯42.82 %/s). CONCLUSION: Increased AT force, loading rate, and stress were observed in runners who habitually wear conventional shoes with rearfoot strike patterns when they wore minimalist shoes. Hence, we recommend a gradual transition to minimalist shoes for runners who habitually wear conventional shoes with rearfoot strike patterns.

Lateral epicondylitis: Current concepts.

BACKGROUND: Lateral epicondylitis, more commonly referred to as 'tennis elbow', is a common condition seen in general practice. It effects approximately 4-7 per 1000 individuals. Despite this, the aetiology and pathophysiology remain poorly understood. Often presenting as lateral elbow pain, the differential diagnosis includes entrapment syndromes, cervical radiculopathy, osseous pathology and inflammatory conditions. Though in 90% of cases the condition is self-limiting, persistent symptoms can be difficult to manage. OBJECTIVE: In this article, a review of recent English-language journal articles explores current concepts related to lateral epicondylitis and examines the evidence behind the recommendation for the use of non-operative and operative treatment modalities. DISCUSSION: Lateral epicondylitis is an enthesopathy associated with the origin of the extensor carpi radialis brevis (ECRB) muscle. A clinical history and examination is usually sufficient to make a diagnosis. Maudsley's and Cozen's clinical tests have a high sensitivity in diagnosing lateral epicondylitis. The available evidence supports the use of non-operative treatment modalities in managing this condition. When comparing the different operative treatments described, there appears to be no significant advantage of intervention over the natural history of lateral epicondylitis.

A Review of Workload-Monitoring Considerations for Baseball Pitchers.

Because of the unique demands of a pitch, baseball players have the greatest percentage of injuries resulting in surgery among high school athletes, with a majority of these injuries affecting the shoulder and elbow due to overuse from throwing. These injuries are believed to occur because of repeated microtrauma to soft tissues caused by the repetitive mechanical strain of throwing. Researchers and practitioners have suggested that baseball pitchers' workloads are a significant risk factor for injury in adolescent players, resulting in lost time and slowing of performance development. The purpose of our review was to investigate the current research relative to monitoring workload in baseball throwers and discuss techniques for managing and regulating cumulative stress on the arm, with a focus on preventing injury and optimizing performance in adolescent baseball pitchers.

The Weekend Warrior: Common Hand and Wrist Injuries in Athletes.

Weekend warriors are individuals who condense their weekly physical activity into extended intervals over one or two days.1 Excessive physical activity can result in a multitude of overuse and traumatic upper extremity injuries. The purpose of this review is to highlight the etiology and management of the more common hand and wrist injuries in athletes.

Risk Factors of Overuse Shoulder Injuries in Overhead Athletes: A Systematic Review.

CONTEXT: Shoulder injuries are highly prevalent in sports involving the upper extremity. Some risk factors have been identified in the literature, but consensus is still lacking. OBJECTIVES: To identify risk factors of overuse shoulder injury in overhead athletes, as described in the literature. DATA SOURCES: A systematic review of the literature from the years 1970 to 2018 was performed using 2 electronic databases: PubMed and Scopus. STUDY SELECTION: Prospective studies, written in English, that described at least 1 risk factor associated with overuse shoulder injuries in overhead sports (volleyball, handball, basketball, swimming, water polo, badminton, baseball, and tennis) were considered for analysis. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: Data were extracted from 25 studies. Study methodology quality was evaluated using the Modified Coleman Methodology Score. RESULTS: Intrinsic factors, previous injury, range of motion (lack or excess), and rotator cuff weakness (isometric and isokinetic) highly increase the risk of future injuries. Additionally, years of athletic practice, body mass index, sex, age, and level of play seem to have modest influence. As for the effect of scapular dysfunction on shoulder injuries, it is still controversial, though these are typically linked. Extrinsic factors, field position, condition of practice (match/training), time of season, and training load also have influence on the occurrence of shoulder injuries. CONCLUSION: Range of motion, rotator cuff muscle weakness, and training load are important modifiable factors associated with shoulder injuries. Scapular dysfunction may also have influence. The preventive approach for shoulder injury should focus on these factors.

Eating, Sleep, and Social Patterns as Independent Predictors of Clinical, Metabolic, and Biochemical Behaviors Among Elite Male Athletes: The EROS-PREDICTORS Study.

Objectives: Physiological hormonal adaptions in athletes and pathological changes that occur in overtraining syndrome among athletes are unclear. The Endocrine and Metabolic Responses on Overtraining Syndrome (EROS) study evaluated 117 markers and unveiled novel hormonal and metabolic beneficial adaptive processes in athletes. The objective of the present study was to uncover which modifiable factors predict the behaviors of clinical and biochemical parameters and to understand their mechanisms and outcomes using the parameters evaluated in the EROS study. Methods: We used multivariate linear regression with 39 participants to analyze five independent variables-the modifiable parameters (caloric, carbohydrate, and protein intake, and sleep quality and duration of concurrent cognitive activity) on 37 dependent variables-that were elected among the parameters evaluated in the EROS study. Results: Carbohydrate intake predicted quick hormonal responses to stress and improved explosive responses during exercise. Protein intake predicted improved body composition and metabolism and caloric intake, regardless of the proportion of macronutrients, predicted muscle recovery, and alertness in the morning. Sleep quality predicted improved mood and excessive concurrent cognitive effort in athletes under intense training predicted impaired metabolism and libido. Conclusions: The results support the premise that eating, sleep, and social patterns modulate metabolic and hormonal function, clinical behaviors, and performance status of male athletes, and should be monitored continuously and actively to avoid dysfunctions.

Biomechanical quantification of deadbug bridging performance in competitive alpine skiers: Reliability, reference values, and associations with skiing performance and back overuse complaints.

OBJECTIVES: (1) To study the reliability of quantifying rear-chain stabilization capacity during deadbug bridging (DBB), (2) to provide reference values for competitive alpine skiers, and (3) to study associations with age, anthropometrics, maturation, skiing performance and back overuse complaints. DESIGN: Cross-sectional. SETTING: Biomechanical field experiment including questionnaires. PARTICIPANTS: 12 healthy subjects (reliability experiment); 133 skiers of the U16 category and 38 of the elite category (main experiment). MAIN OUTCOME MEASURES: DBB performance was quantified using 3D motion capture as the maximum amplitude of the relative vertical displacement of two pelvis markers (DBBdisplacement). Additionally, in U16 skiers, age, anthropometrics, maturation, skiing performance, and back overuse complaints were assessed. RESULTS: The reliability experiment revealed an ICC(3,1) and 95% CI of 0.81 [0.61, 0.93]. Within-subject SEM was 3.89 mm [3.16 mm, 5.12 mm]. Depending on sex and category, medians of DBBdisplacement in skiers ranged between 29 mm and 45 mm. DBBdisplacement differed between elite and U16 skiers (p < 0.001), but not between sexes. In U16 skiers, DBBdisplacement was independent of age, anthropometrics, and biological maturation, however, associated with skiing performance and back overuse complaints (p < 0.05). CONCLUSION: The proposed approach may be considered an adequate method to quantify athletes' rear-chain stabilization capacity.