A portable inflatable soft wearable robot to assist the shoulder during industrial work.

Repetitive overhead tasks during factory work can cause shoulder injuries resulting in impaired health and productivity loss. Soft wearable upper extremity robots have the potential to be effective injury prevention tools with minimal restrictions using soft materials and active controls. We present the design and evaluation of a portable inflatable shoulder wearable robot for assisting industrial workers during shoulder-elevated tasks. The robot is worn like a shirt with integrated textile pneumatic actuators, inertial measurement units, and a portable actuation unit. It can provide up to 6.6 newton-meters of torque to support the shoulder and cycle assistance on and off at six times per minute. From human participant evaluations during simulated industrial tasks, the robot reduced agonist muscle activities (anterior, middle, and posterior deltoids and biceps brachii) by up to 40% with slight changes in joint angles of less than 7% range of motion while not increasing antagonistic muscle activity (latissimus dorsi) in current sample size. Comparison of controller parameters further highlighted that higher assistance magnitude and earlier assistance timing resulted in statistically significant muscle activity reductions. During a task circuit with dynamic transitions among the tasks, the kinematics-based controller of the robot showed robustness to misinflations (96% true negative rate and 91% true positive rate), indicating minimal disturbances to the user when assistance was not required. A preliminary evaluation of a pressure modulation profile also highlighted a trade-off between user perception and hardware demands. Finally, five automotive factory workers used the robot in a pilot manufacturing area and provided feedback.

Preventive interventions for throwing injuries in baseball players: a scoping review.

BACKGROUND: Shoulder and elbow pain are the common complaints associated with throwing injuries in baseball players. Prospective studies evaluating the effectiveness of stretching in increasing posterior shoulder flexibility or strengthening the external rotator muscles as preventive strategies for throwing injuries in baseball players have been published. However, there are limited reviews highlighting the role of preventive interventions for throwing injuries in baseball players. Therefore, this scoping review aimed to summarize the existing literature on preventive interventions for throwing injuries in baseball players. METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, and Scopus databases on 3 March 2023. Two independent reviewers screened the studies based on the eligibility criteria. We extracted existing literature on preventive interventions and effectiveness for throwing injuries in baseball players, and participants' characteristics and results were extracted from the studies. This scoping review was performed in accordance with the Extended Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement for Scoping Reviews. RESULTS: The initial database search yielded 1170 articles, four of which met the eligibility criteria. Of the included studies, two were randomized controlled trials, and the remaining two were prospective cohort studies. Eligible studies targeted youth-to high school-level players and focused on preventive programs for throwing injuries that manifest in the upper extremities of baseball players. The outcome measure most commonly used to quantify the effectiveness of prevention programs was the incidence of shoulder and elbow injuries, although the definitions vary among studies. The prevention program included sleeper stretching, shoulder external rotation strengthening exercises, and comprehensive prevention programs (focusing on improving the elbow, shoulder, and hip range of motion; rotator cuff and periscapular muscle strength; posture; and lower extremity balance). Each prevention program was reported to have the potential to reduce the incidence of throwing injuries in baseball players, and two studies suggested that high compliance with the program led to a lower injury risk. CONCLUSION: This scoping review confirmed the presence of studies that examined preventive interventions for throwing injuries in baseball players. Preventive interventions that may reduce throwing injuries in baseball players include sleeper stretching, shoulder external rotation strengthening exercises, and comprehensive prevention programs. However, the characteristics of participants (eg, age, sports level, and position) and the definition of injury varied among previous studies. Injury profiles and prevention strategies may differ according to age, sport level, and position of players, and more studies are needed to prove this issue.

Dental Ergonomics: How Clinicians Can Prevent Musculoskeletal Disorders and Shoulder Injuries.

Because of the nature and positioning of their work, dental professionals are at a relatively high risk for musculoskeletal disorders (MSDs) and shoulder injuries. The most common injuries occur in the neck, back (spine), shoulders, elbows, and hands. Poor posture and fatigue are the most significant causes of MSDs. Poor posture, repetitive motions, and working in awkward positions cause MSDs and shoulder injuries in dental professionals. The use of ergonomic supports can be effective in preventing MSDs and shoulder injuries. Choosing and implementing ergonomic tools, such as an appropriate chair, magnifying devices for improved visualization, and specific ergonomic equipment, can help avoid physical stress and injuries.

Developing the Singapore youth shoulder overuse injury prevention program.

OBJECTIVES: To develop the Singapore Youth Shoulder Overuse Injury Prevention Program specifically for competitive overhead youth athletes in Singapore. DESIGN: Two-round online Delphi technique with experts and a feasibility assessment questionnaire with youth athletes who represented end-users. SETTING: Volleyball for youth athletes. PARTICIPANTS: Experts were recruited through purposive sampling based on their knowledge and experience. Youth athletes were recruited though a volleyball club. MAIN OUTCOME MEASURES: The main outcome measure was the level of consensus on the proposed (1) exercise program for the overhead youth athletes, (2) education program regarding overuse injuries for coaches of overhead youth athletes, and (3) education program regarding overuse injuries for overhead youth athletes. Consensus was set at 75% agreement in this study. RESULTS: Eighteen experts completed the two Delphi rounds with 100% response rate. Consensus was achieved for the exercise program and both education programs. Twelve youth athletes completed the feasibility assessment questionnaire and found the exercises to be feasible in terms of usefulness, practical use, instructions, duration, and ease of execution. CONCLUSION: Consensus was reached for the Singapore Youth Shoulder Overuse Injury Prevention Program, and feasibility of execution by end-users was successfully determined.

Prevention of shoulder injuries in volleyball players: The usefulness and efficiency of a warm-up routine.

OBJECTIVES: The objective of this study was to assess the efficiency of a warm-up routine focused on shoulder injury prevention in volleyball players. DESIGN: Prospective study. SETTING: University. PARTICIPANTS: Eight recreational volleyball teams (44 males, 49 females) were included in the study and assigned to two different groups (prevention or control) in a blinded way. In the prevention group, the players had to perform specific exercises at the beginning of each training session twice a week. MAIN OUTCOME MEASURES: Injuries were recorded monthly in both groups with an online questionnaire. RESULTS: A significant decrease in the total number of injuries as well as in the severity of the injuries was observed in the prevention group in comparison to the control group (p = 0.0001-0.013). For the shoulder, a decrease in injury incidence was also observed in the prevention group. This decrease reached significance in male players (p = 0.045). CONCLUSIONS: The program appears to be efficient to reduce the risk of shoulder injuries in recreational volleyball players. Adjustments in the duration and in the contents of the program will have to be made to further improve compliance and better meet the requirements of both players and trainers.

Diagnosis, prevention and treatment of common shoulder injuries in sport: grading the evidence - a statement paper commissioned by the Danish Society of Sports Physical Therapy (DSSF).

This statement paper summarises and appraises the evidence on diagnosis, prevention, and treatment of common shoulder injuries in sports. We systematically searched Medline and Embase. The Grading of Recommendations Assessment, Development and Evaluation tool was applied to evaluate the overall quality of evidence.For diagnosis, we included 19 clinical tests from mixed populations. Tests for anterior instability, biceps-labrum complex injuries and full subscapularis rupture had high diagnostic accuracy (low to moderate quality of evidence).For prevention, the Oslo Sports Trauma Research Center, the Shoulder Control, the FIFA 11+ shoulder injury prevention programmes, and a baseball-specific programme (range of motion, stretching, dynamic stability and strengthening exercises) showed moderate to large effect size in reducing the risk of shoulder injury compared with no intervention (very low to moderate quality of evidence).For treatment, a rehabilitation programme including stretching, ice packs, electrotherapy and compression, and strengthening exercises showed a large effect size in reducing pain and disability compared with no intervention in athletes with subacromial impingement syndrome (very low to moderate quality of evidence). For the treatment of supraspinatus tendinopathy, hyperthermia treatment (heating the skin to 38°C-40°C) resulted in large effect size in reducing pain and disability compared with ultrasound or pendular swinging and stretching exercises (moderate quality of evidence). Strengthening exercise alone or in combination with stretching exercises promoted a large effect in reducing shoulder pain (cohort studies, no comparators) (very low quality of evidence). The quality of evidence for most estimates was low to moderate, indicating that future high-quality research may alter our recommendations for clinical practice.

Evidence for taping in overhead athlete shoulders: a systematic review.

Taping is a popular approach and is often used as part of a multifactorial injury prevention programme for athletes. The aim of this study was to evaluate the current literature regarding the effects of shoulder taping in overhead athletes. Literature search was performed related to rotational range of motion (RoM), posterior shoulder tightness (PST), kinematics, muscular activity, acromiohumeral distance (AHD), proprioception, strength, and performance. Twenty studies were eligible. The majority of the applied taping methods were scapular and humeral head repositioning taping. Across all studies, there was limited to moderate evidence in favour of taping in overhead athletes with regard to rotational RoM, AHD, proprioception, and altering scapular kinematics, while taping did not enhance PST, muscular activity, shoulder strength, and performance. Therefore, the current evidence showed taping can alter some of the investigated factors that may have a therapeutic or preventive role. However, in the management of the athlete shoulder, taping-only approaches should not be focused on, and taping can be integrated in a more comprehensive approach for the overhead athletes.

Effectiveness of shoulder injury prevention programs in an overhead athletic population: A systematic review.

OBJECTIVE: To analyze the effectiveness of shoulder injury prevention programs in overhead athletes. DESIGN: Systematic Review. METHODS: CINAHL, Embase, PubMed, and SPORTDiscus electronic databases were searched from database inception through December 2020 for randomized controlled or prospective cohort studies that implemented shoulder injury prevention programs in overhead athletes and reported shoulder injury incidence rates. RESULTS: Seven studies fulfilled the inclusion criteria. Two studies reported on odds ratios (OR) that resulted in a reduction of shoulder injuries in overhead athletes following shoulder strengthening and flexibility exercises (OR, 0.72; 95% CI; 0.52, 0.98; OR, 0.22; 95% CI; 0.06, 0.75). One study reported on hazard ratio (HR) that resulted in a reduction of shoulder injuries following stretching of the posterior capsule (HR, 0.36; 95% CI; 0.13, 0.95). CONCLUSION: There is limited research surrounding the effectiveness of shoulder injury prevention programs in overhead athletes specific to injury reduction. Only three studies reported a favorable effect in terms of injury prevention, with only one study at low risk of bias. At present, no conclusions can be made regarding the effectiveness of shoulder injury prevention programs in the overhead athlete.

The FIFA 11+ Shoulder Injury Prevention Program Was Effective in Reducing Upper Extremity Injuries Among Soccer Goalkeepers: A Randomized Controlled Trial.

BACKGROUND: Soccer is one of the most popular sports worldwide. Goalkeepers are more likely to injure their upper limbs, particularly their shoulders, than outfield players. To reduce upper extremity injuries, the FIFA 11+ Shoulder Injury Prevention Program (FIFA 11+S) was developed. PURPOSE: The purpose of this study was to assess the effectiveness of the FIFA 11+S program in reducing the incidence of upper extremity injuries among amateur soccer goalkeepers. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 726 goalkeepers, who were blinded to study intent, were randomly assigned to the experimental group (n = 360) or control group (n = 366). The experimental group was instructed to perform the FIFA 11+S program before all training sessions for 1 season (6 months). The control group was instructed to continue performing their usual routine warm-up program before training sessions for 1 season. Primary outcomes included the incidence of upper extremity injury and incidence of mechanism, type, and severity of injury measured using injury risk ratios (IRR); compliance with the experimental and control interventions was also recorded. RESULTS: A total of 50 injuries (0.62 injuries per 1000 exposure-hours) were reported in the experimental group, and 122 injuries (1.94 injuries/1000 hours) were reported in the control group. The FIFA 11+S program reduced the total number of upper extremity injuries by 68% (IRR = 0.32 [95% CI, 0.27-0.34]) compared with the usual warm-up. The FIFA 11+S program reduced the incidence of contact injury (IRR = 0.30 [95% CI, 0.25-0.31]), noncontact injury (IRR = 0.40 [95% CI, 0.35-0.43]), initial injury (IRR = 0.34 [95% CI, 0.29-0.36]), recurrent injury (IRR = 0.20 [95% CI, 0.17-0.21]), and overuse injury (IRR = 0.40 [95% CI, 0.35-0.43]). Participants in the experimental group demonstrated a significant decrease in injuries of minor (IRR = 0.32 [95% CI, 0.27-0.34]) and moderate severity (IRR = 0.33 [95% CI, 0.29-0.35]) compared with the control group. We noted no difference in compliance between the experimental and control groups (80% vs 73%, respectively; P = .92). CONCLUSION: The FIFA 11+S program resulted in 50% fewer upper extremity injuries among soccer goalkeepers, compared with a regular warm-up. REGISTRATION: ACTRN12618001080213 (Australian New Zealand Clinical Trials Registry).

Injury Prevention Programs for Throwing Injuries in Softball Players: A Systematic Review.

CONTEXT: Throwing-related injuries occur commonly in softball players. Preventative programs can be implemented to assist in identifying and correcting risk factors that could potentially lead to injury and therefore time missed from both practice and games. OBJECTIVE: The purpose of this study was to determine if position-specific injury prevention programs have been developed to decrease the risk of throwing-related injuries in softball players. DATA SOURCES: A systematic review was performed using the PRISMA (Preferred Reporting Items of Systematic Reviews and Meta-Analyses) guidelines. PubMed, PMC, and EBSCO were searched for articles on injury prevention programs using the following key terms: softball, injury prevention, throwing injuries, pitcher, and shoulder. STUDY SELECTION: Studies that involved fast-pitch softball and included female participants as well as rehabilitation programs were included. Articles that highlighted slow-pitch softball or did not include female participants were excluded. LEVEL OF EVIDENCE: Level 1. DATA EXTRACTION: The initial search identified 1605 articles. After implementing a filter, 131 articles remained. Thirteen articles were screened out as duplicates. After screening for inclusion criteria, 7 articles remained and were included in the systematic review. RESULTS: Decreased range of motion (ROM) in both the upper and the lower extremities, unbalanced muscular strength, and fatigue were identified as risk factors for throwing injuries in softball players. Within the upper extremity, strength and ROM of the rotator cuff muscles, biceps, and extensors of the forearm were emphasized. The main focus of the lower extremity was the strength of the gluteal muscles and ROM of the lumbopelvic-hip complex. Only 1 study detailed an injury prevention program for softball players. The prevention program outlined was generalized for all softball players and was not position specific. CONCLUSION: There is a paucity of information about injury prevention programs for softball players. Of the evidence analyzed, balanced strengthening of the upper and lower extremities while maintaining dynamic range of motion was frequently utilized in developing an injury prevention program.

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.

Current Concepts in Arm Care Exercise Programs and Injury Risk Reduction in Adolescent Baseball Players: A Clinical Review.

CONTEXT: Awareness of important injury risk factors associated with excessive pitching volume has been highlighted in the literature, but injury rates remain high. Shoulder pain in baseball players is associated with various changes in musculoskeletal movements, which presents as measurable impairments throughout the kinetic chain. Baseball coaches and rehabilitation professionals have utilized exercise programs targeting strength and flexibility of the throwing arm to prevent injuries. The purpose of this review is to summarize the current evidence regarding the effectiveness of arm care exercise programs in reducing upper extremity injury rates in adolescent baseball players. EVIDENCE ACQUISITION: A search of electronic databases, including CINAHL with full text, MEDLINE, and SPORTDiscus was conducted to retrieve available articles in English from the years 2010 through 2020. The search terms injury prevention, exercise, and adolescent baseball were used. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Improving shoulder internal rotation range of motion by stretching the posterior shoulder muscles daily was associated with a 36% risk reduction of shoulder and elbow injuries. Group-based arm care exercise programs that target multiple musculoskeletal impairments demonstrated an approximately 50% reduced risk of elbow injury. CONCLUSION: For adolescent baseball players, arm care injury prevention programs focusing on important musculoskeletal impairments are effective at reducing injury incidence rates. Multimodal injury prevention programs that improve multiple musculoskeletal impairments are more comprehensive and may result in better injury reduction than programs focusing on a singular impairment.

The challenge of the sporting shoulder: From injury prevention through sport-specific rehabilitation toward return to play.

Shoulder injuries and sports-related shoulder pain are substantial burdens for athletes performing a shoulder loading sport. The burden of shoulder problems in the athletic population highlights the need for prevention strategies, effective rehabilitation programs, and a individually based return-to-play (RTP) decision. The purpose of this clinical commentary is to discuss each of these 3 challenges in the sporting shoulder, to assist the professional in: (1) preventing injury; (2) providing evidence-based practice rehabilitation and; (3) to guide the athlete toward RTP. The challenges for injury prevention may be found in the search for (the interaction between) relevant risk factors, develop valid screening tests, and implement feasible injury prevention programmes with maximal adherence from the athletes. Combined analytical and functional testing seems mandatory screening an athlete's performance. Many questions arise when rehabilitating the overhead athlete, from exercise selection, over the value of stretching, toward kinetic chain implementation and progression to high performance training. Evidence-based practice should be driven by the available research, clinical expertise and the patient's expectations. Deciding when to return to sport after a shoulder injury is complex and multifactorial. The main concern in the RTP decision is to minimize the risk of re-injury. In the absence of a "gold standard", clinicians may rely on general guidelines, based on expert opinion, regarding cutoff values for normal range of motion, strength and function, with attention to risk tolerance and load management.

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.

Influencia de las medidas preventivas ergonómicas en el desarrollo de secuelas por patología no traumática del hombro / Influence of Ergonomic Preventive Resources in Development of Sequels Due to Non-Traumatic Diseases of the Shoulder

OBJETIVO: Describir las secuelas referidas en los casos atendidos por patología no traumática del hombro. Y conocer cómo se asocian con la presencia de secuelas las características sociodemográficas, disponer de conocimientos en prevención de riesgos laborales y los requerimientos ergonómicos del puesto de trabajo. MÉTODOS: Estudio observacional transversal en una población de 345 pacientes atendidos durante un año en las consultas de un centro de atención primaria de salud en Alicante. Mediante la prueba de la Ji-cuadrado se estudiaron las asociaciones entre las secuelas y el resto de variables. RESULTADOS: El 53,9% (n = 186) de los participantes refirieron presentar secuelas derivadas, sobre todo dolor ocasional asociado o no a limitación de la movilidad. Son factores de riesgo: un bajo nivel de estudios, actividades de limpieza y sector industrial, alzar los brazos por encima del hombro y la monotonía en las tareas. Sin embargo, son factores protectores: el sexo masculino, disponer de información sobre los riesgos laborales, equipos de protección individual, existencia de Servicio de Prevención de Riesgos Laborales, evaluación de riesgos, plan de prevención y los reconocimientos médicos periódicos. Conocer los riesgos del puesto se mostró como factor de protección independiente frente al desarrollo de secuelas (Ora = 0,2; IC 95% = 0,1-0,4). Sin embargo, alzar el brazo por encima del hombro, se comporta como factor de riesgo independiente para el desarrollo de secuelas por patología del hombro (Ora = 2,1; IC 95% = 1,0-4,3). CONCLUSIONES: La combinación de estrategias ergonómicas y formativas parecen útiles para la prevención del desarrollo de secuelas a nivel del hombro

OBJECTIVE: To describe the sequelae referred to the cases attended by non-traumatic diseases of the shoulder. To know how sociodemographic characteristics, preventive knowl-edge about the workplace and ergonomic requirements are associated with the presence of sequelae. METHODS: Cross-sectional observational study in a population of 345 patients attended for a year in the consultations of a primary health care center in Alicante. Through the Chi-square test, the associations between the sequels and the rest of the variables were studied. RESULTS: 53.9% (n = 186) of the participants reported having sequelae derived, especially occasional pain associated or not with limitation of joint mobility. They are risk factors: a low level of studies, cleaning activities and industrial sector, raising the arm over the shoulder and the monotony in the workplace. However, they are protective factors: male sex, having information on occupational risks, Personal Protective Equipment, the existence of a Labor Risk Prevention Service, Risk Assessment, Prevention Plan and periodic medical examinations. Knowing the risks of the position was shown as an independent protection factor against the development of secondary sequelae in the shoulder (ORa = 0,2; IC 95% = 0,1-0,4). However, to raise the arm above the shoulder, behaving as an independent risk factor for the development of sequelae due to shoulder pathology (ORa = 2,1; IC95% = 1,0-4,3)

Does an effective shoulder injury prevention program affect risk factors in handball? A randomized controlled study.

BACKGROUND: Shoulder problems are common in handball, but injury risk reduction is possible by implementing a prevention program. However, player compliance to the program remains a challenge, with feedback from players that the program is too time consuming. AIM: To develop a more efficient program, we aimed to assess the effect of the Oslo Sports Trauma Research Center shoulder injury prevention program on external rotation (ER) strength and internal rotation (IR) range of motion (ROM), considered to represent key risk factors for injury. METHODS: Four youth handball teams (three females, one males, 57 players, mean age 17.1 years) were randomized to an intervention or control group. The intervention program was conducted three times per week as a part of handball warm-up for 18 weeks, supervised by physical therapists. The main outcome variables were the between-group differences in ER strength and IR ROM change from baseline to postintervention. Isometric ER strength was measured with a handheld dynamometer and IR ROM with a digital goniometer. RESULTS: Mean dominant shoulder isometric ER strength increased both in the intervention (10%) and the control group (6%) during the intervention, but there was no significant group by time interaction (group difference: 0.06 N/kg (95% CI: -0.04 to 0.17). IR ROM did not change in either group during the intervention. CONCLUSION: The Oslo Sports Trauma Research Center shoulder injury prevention program did not affect the risk factors ER strength and IR ROM. The preventive effect of the program must therefore be due to other factors.

Youth Baseball Pitch Counts Vastly Underestimate High-effort Throws Throughout a Season.

BACKGROUND: The primary purpose of this study was to compare the number of pitches thrown by youth baseball players under the official league guidelines versus the number of "high-effort" throws recorded by a validated digital sensor worn by the players during a season. METHODS: In total, 11 and 12-year-old youth baseball players from a single league were provided an elbow sleeve and sensor to wear each time they threw a baseball for an entire baseball season. The sensor tracked total throws and pitch-equivalent high-effort throws for the season. Official pitch counts were collected at each game from the official scorekeepers. RESULTS: A total of 19 players participated in the study. The sensor-determined mean total throw count (1666.2±642.2) and mean high-effort throw count (576.9±329.3) per player were both significantly higher, P<0.0001 and P=0.02, respectively, than the mean official pitch count (168.1±122.4). CONCLUSIONS: Our findings demonstrate that youth players make significantly more total throws and high-effort, or pitch-equivalent, throws, than what is recorded by the official pitch counts. Further research is needed to determine a safe annual "throw count" for young throwing athletes and to determine which types of throws, in addition to pitches, put youth throwers at risk for injury. LEVEL OF EVIDENCE: Level IV.

The Self-Assessment Corner for Shoulder Strength: Reliability, Validity, and Correlations With Upper Extremity Physical Performance Tests.

CONTEXT: Rotator cuff weakness and rotation ratio imbalances are possible risk factors for shoulder injury among overhead athletes. In consensus statements, organizations have highlighted the importance of a screening examination to identify athletes at risk of injury. The screening should be portable and designed to be feasible in many different environments and contexts. OBJECTIVE: To evaluate the reliability and validity of the Self-Assessment Corner (SAC) for self-assessing shoulder isometric rotational strength and examining whether performance on 2 physical performance tests was correlated with isometric shoulder rotational strength using the SAC in handball players. DESIGN: Cross-sectional study. SETTING: Sport setting. PATIENTS OR OTHER PARTICIPANTS: A first sample of 42 participants (18 men, 24 women) was recruited to determine the reliability and validity of the SAC. In a second sample of 34 handball players (18 men, 16 women), we examined correlations between physical performance tests and the SAC. MAIN OUTCOME MEASURE(S): The SAC was used to measure isometric rotational strength with the upper extremity at 90° of abduction in the frontal plane and 90° of external rotation and the elbow flexed to 90° with neutral rotation of the forearm. The SAC findings were compared with those from manual testing. Results from the seated medicine ball throw (SMBT) and closed kinetic chain upper extremity stability test (CKCUEST) were used to establish relationships with the SAC. We calculated intraclass correlation coefficients to determine relative reliability and used standard error of measurement and minimal detectable change to quantify absolute reliability. Relationships among the different strength-testing procedures and with the physical performance tests were determined using the Pearson product moment correlation coefficient (r) or Spearman rank correlation coefficient (rs). RESULTS: We observed good to excellent reliability (intraclass correlation coefficient [2,k] range = 0.89 to 0.92). The standard error of measurement varied from 3.45 to 3.48 N. The minimal detectable change with 95% confidence intervals ranged from 8.06 to 8.13 N. Strong correlations were present among strength procedures (r = 0.824, rs range = 0.754-0.816). We observed moderate to strong correlations between the CKCUEST findings and rotational strength (r range = 0.570-0.767). Moderate correlations were found between rotational strength and SMBT (r range = 0.573-0.626). CONCLUSIONS: The SAC is a clinically applicable and standardized protocol for self-assessing rotational strength in young healthy adults without pathologic conditions. Performance on the SMBT and CKCUEST may be valuable as a screening tool to further assess shoulder strength.