History Of Shoulder Injury Research Articles

Exploring the Discriminant Validity of the Modified Arm Care Screen (MACS), Designed for Overhead Athletes, in Detecting Musculoskeletal Risk Factors in the General Population

Background: Shoulder pain is the third most common musculoskeletal issue in primary care, affecting up to 50% of patients six months post-consultation, leading to significant functional impairments and societal costs, especially due to sick leave. Shoulder injuries are particularly prevalent among ‘overhead athletes’ in sports like swimming, volleyball, and handball, with high injury rates reported annually. Screening tools like the Arm Care Screen (ACS) have been used to effectively identify athletes at risk of shoulder injuries. However, their applicability to the general population is less understood. This study aimed to assess the discriminant validity of a modified ACS (MACS) in detecting musculoskeletal risk factors among non-athletes. Methods: A prospective cross-sectional study was conducted with 30 asymptomatic subjects over 18, excluding those with a history of shoulder injuries or surgeries. The MACS, comprising four tests, was administered, and its diagnostic performance was evaluated through sensitivity, specificity, predictive values, and likelihood ratios. Results: The results indicated low sensitivity (0–47.62%) and variable specificity (55.56–100%), suggesting that the MACS may not effectively identify risk factors in the general population. Positive and negative predictive values were inconsistent (ranging from 0 to 100), as well as positive and negative likelihood ratios (ranging from 0 to 3.47), highlighting the need for non-athlete-specific screening tools. Conclusion: While the MACS shows promise in athletes, its application in the general population requires further refinement. This study underscores the necessity for tailored screening methods to enhance the early detection and prevention of musculoskeletal issues in diverse populations.

Clinical and ultrasonographic evaluation of uninjured dominant shoulder in amateur rugby players vs a control group: a pilot study

BackgroundRugby is a sport involving a great number of shoulder collisions. Traumatic stress of the shoulder can weaken the static stabilizers and promote major injuries as dislocation or full-thickness tears of the rotator cuff. The goal of this study is to evaluate the clinical and ultrasonographic dominant shoulder factures in a group of amateur rugby players, with no history of shoulder injuries, and to compare them with those of a control group.Methods52 male subjects join in the study: 26 amateur rugby players and 26 subjects, which did not practice rugby or competitive sport. Clinical history was obtained from all subjects, followed by dominant shoulder physical and ultrasonographic exams.ResultsRugby players showed a higher prevalence of positive clinical test, suggesting subacromial impingement than control group (p = 0.01).Among rugby group, five players (19,2%) showed positive test for radiculopathy (p = 0,02), and ten players (73,1%) reported shoulder pain needing pain-reliever drugs at list one time in the last six months (p = 0.001). In rugby group, ultrasound exams showed 23,1% degenerative changes and 30,8% tendon calcifications in supraspinatus tendons (p < 0.05).ConclusionsUninjured dominant shoulder of rugby players shows higher prevalence of clinical and ultrasound changes compare to control. Some rugby players without history of cervical symptoms show positive clinical test of cervical radiculopathy. Clinical and ultrasonographic monitoring of the shoulder can play a role in prevention and knowledge of silent shoulder damage in these athletes.

Musculoskeletal, Functional and Performance Impairment in Female Overhead Athletes with a Previous Shoulder Injury.

Shoulder injuries are substantial problems in overhead athletes, and more studies are necessary to deepen the knowledge on this type of injury. The objective of this study was to compare the overall function and performance of female overhead athletes with and without a previous history of shoulder injuries. In this cross-sectional study, female overhead athletes with and without a previous shoulder injury were included. Muscular impairment, the stability of the shoulder, strength, scapular dyskinesia, functionality and sports performance were evaluated. A total of 50 females were included. There were significant differences in strength (p = 0.046) and stability (p = 0.039) between groups, with a poorer score in the group with a history of shoulder injury. Regarding scapular dyskinesia, significant differences were also observed between groups (p = 0.048), with higher levels of dyskinesia in the group with previous shoulder injury. Also, muscular impairment showed significant differences between groups for the three muscles evaluated (p < 0.005). Additionally, the group without a previous shoulder injury presented with a significantly greater score in functionality (p = 0.046) and sports performance (p = 0.004). In conclusion, previous shoulder injuries are an important factor to take into account in female overhead athletes. Players with a history of shoulder injury present clinical impairments during the game, leading to poorer functional status and performance in sport.

Influence of body mass index on severity of rotator cuff tears

Research on the relationship between obesity and rotator cuff tears (RCTs) has been limited to the impact of obesity on the results of arthroscopic repair of RCTs; thus, a need for rigorous research controlling for other factors affecting RCTs is warranted, especially to better understand the impact of body mass index (BMI) on RCT severity. A retrospective study of admission records contained in electronic medical records pertaining to patients who were admitted for RCT repair on one shoulder between January 2018 and July 2022 was conducted. In total, 386 patients were included. In accordance with guidance regarding obesity from Taiwan's Ministry of Health and Welfare, patients were divided into three groups: underweight or normal weight (BMI <24.0 kg/m2), overweight (BMI 24.0-26.9 kg/m2), or obese (BMI ≥27.0 kg/m2). Magnetic resonance imaging (MRI) was used to assess RCT severity in terms of four parameters: Patte stage (PS), fatty infiltration (FI), anteroposterior tear size (AP), and retraction size. Multinomial logistic regression analysis was performed on Patte stage and FI grade data, and multiple linear regression analysis was performed on AP tear size and retraction size in order to analyze impact. Our results revealed that the average age of the 386 patients was 63.41 years (SD = 9.29) and the mean BMI was 25.88 (SD = 3.72) kg/m2. We found significant differences in PS (p =.003), FI (p <.001), retraction size (p =.001), and AP tear size (p =.001) among patients who were underweight or normal weight, overweight, and obese. After controlling for other risk factors, including age, gender, RCT-prone occupation, duration of shoulder pain prior to surgery, history of shoulder injury, and tobacco use, we found that obese patients had higher severity levels in PS (B = 1.21, OR = 3.36, p = .029), FI (B = 1.38, OR = 3.96, p < .001), retraction size (β = .18, p = .001), and AP tear size (β = .18, p = .001) compared to underweight or normal weight patients. Our study demonstrates that a correlation exists between BMI-measured obesity and RCT severity. We therefore suggest that adults control their weight given that maintaining a healthy weight is highly associated with better shoulder health.

Injury, Training, Biomechanical, and Physiological Profiles of Professional Breakdancers.

Breakdancing or breaking will enter the Olympics in 2024, however, there is a paucity of literature exploring the epidemiology, demands, and performance. The purpose of this study was to describe injury and training profiles, along with the results of a short performance test battery, in a group of elite breakers. Cross-sectional study (retrospective). Fourteen breakdancers (breakers) (4 Bgirls, 10 Bboys) participated in an interview regarding their injury and training history, endurance test (cycle VO2max testing), counter movement jump, squat jump, drop jump, isometric hip abduction, adduction, shoulder external and internal rotation strength testing on a fixed-frame dynamometer. Breakers were divided into elite (n=10) and developing (n=4) based on their qualification for a world finals competition; Wilcoxen rank sums were used to compare the two groups, or in the case of strength testing between those with and without an injury history. The breakers had a median 11.0 [10.0 - 14.0] years breaking experience and trained 24.4 [20.5 - 30.0] hours per week. The knee was the most commonly injured body part and most frequently injured joint, with the thigh being the most common site for muscle injuries. There were no differences in endurance testing or jump height testing results between elite and developing breakers. There was no difference in shoulder external or internal rotation strength between athletes with a history of shoulder injury and those without. Similarly, there was no difference in hip abduction or adduction strength in those with a history of hip injury and those without. The results of this study should be viewed with caution due to the small sample size. However, this study is the first to publish functional and physiological descriptives on breakers. The authors hope these results support clinicians treating breakers as well as encourages future research related to breaking. 2b.

Shoulder injuries in Facioscapulohumeral muscular dystrophy patients (P6-8.001)

<h3>Objective:</h3> To describe the types, prevalence, and history of shoulder injuries in patients with facioscapulohumeral muscular dystrophy (FSHD). <h3>Background:</h3> FSHD is a dominantly inherited, slowly progressive muscular dystrophy with variable clinical manifestations. It usually initially presents as weakness in the face, shoulder, and upper extremities, eventually extending to the lower body. MRI studies have shown that wasting in the shoulder tends to follow a muscle-specific pattern, but to date there are no studies investigating shoulder injuries as an outcome, nor their impact on patients. <h3>Design/Methods:</h3> We distributed a cross-sectional anonymous web-administered survey of adult FSHD patients identified through the US National FSHD Registry and the FSHD Society registry. The survey collected FSHD history, functional status, severity scores, and detailed history of shoulder injury (defined as “any shoulder condition that caused pain, stiffness, or dysfunction in addition to that from FSHD”). <h3>Results:</h3> We identified 613 FSHD patients ranging from 18 to 91 years old (M=56.4, SD=14.7). Average age of symptom onset and diagnosis were 24 and 35, respectively, with an average Brooke Upper Extremity Score of 2.7 (SD=1.03). 89% of patients reported current shoulder weakness, while 34% reported a history of shoulder injury. The most-reported injuries were rotator cuff tendinitis/tendinopathy and rotator cuff tear, both with a prevalence of 9.8% – followed by subacromial bursitis (7.1%), shoulder impingement (6.0%), and dislocated shoulder (5.0%). Of the patients who reported a history of at least one shoulder injury: 42% believed that FSHD was entirely to blame, and 49% rated the impact of their injury on their life – at its worst – at 8/10 or higher. <h3>Conclusions:</h3> By exploring the previously undescribed burden of shoulder injuries in the FSHD patient population, this study may improve patients’ understanding of their condition and inform clinicians’ approach to monitoring the disorder. <b>Disclosure:</b> Mr. Liu has nothing to disclose. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving as a Consultant for DYNE Therapeutics. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Arrowhead Pharma. Dr. Tawil has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Fulcrum Therapeutics. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Acceleron Pharma. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for MT Pharma. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Roche Pharma. Dr. Tawil has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for miRecule. The institution of Dr. Tawil has received research support from Friends of FSH Research. The institution of Dr. Tawil has received research support from FSH Society. The institution of Dr. Tawil has received research support from NIH. The institution of Dr. Tawil has received research support from Fulcrum. Dr. Tawil has received intellectual property interests from a discovery or technology relating to health care. Dr. Tawil has received publishing royalties from a publication relating to health care. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Arrowhead. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving as a Consultant for ML Bio. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving as a Consultant for MT Pharma. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Epic Bio. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Armatus . Dr. Statland has received personal compensation in the range of $10,000-$49,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Dyne Therapeutics. Dr. Statland has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Avidity . Dr. Statland has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Fulcrum Therapeutics. Dr. Statland has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Roche. The institution of Dr. Statland has received research support from NIH. The institution of Dr. Statland has received research support from FSHD Society. The institution of Dr. Statland has received research support from Friends of FSH Research. The institution of Dr. Statland has received research support from FSHD Canada. The institution of Dr. Statland has received research support from MDA.

The Differences of Shoulder Range of Motion and Dynamic Stability in Upper Extremity Depending on Ages and Experiences of Shoulder Injuries among Volleyball Players

PURPOSE: This study aimed to verify the differences in shoulder range of motion (ROM) and dynamic stability in the upper extremities depending on the players’ ages and frequency of sports injuries in the shoulder joint.METHODS: A total of 519 volleyball players enrolled in the Korea Volleyball Association and Korean Volleyball Federation participated in this study. All participants answered questions about their experiences of sports-related shoulder injuries and were then categorized into shoulder-injured and non-injured groups. Shoulder ROM (flexion/extension and internal/external rotation) and upper quarter Y-balance (YBT-UQ) were tested by trained examiners. The YBT-UQ was normalized to the arm length (%AL) of the players.RESULTS: Among elementary and middle school players, the shoulder-injured group had lower internal rotation than the non-injured group. In addition, elementary school players with a history of shoulder injuries performed worse in the YBT-UQ test. Regardless of their history of shoulder injury, older patients tended to have decreased shoulder flexion and extension. In the injured group, younger players had lower internal rotation of the shoulder.CONCLUSIONS: These results showed that player age should be considered for rehabilitation to prevent shoulder sports-related injuries in volleyball players.

Prevalence of Glenohumeral Internal Rotation Deficit and Sex Differences in Range of Motion of Adolescent Volleyball Players: A Case-Control Study.

Shoulder range of motion (ROM) adaptation is common observed among volleyball players, but studies on the shoulder joint function of adolescent athletes are lacking. This study aimed to clarify the prevalence of glenohumeral internal rotation deficit (GIRD) among adolescent players and differences in ROM based on sex. A questionnaire survey and ROM measurements of the shoulder joint and trunk using a plastic goniometer were conducted on 123 volleyball players (63 males and 60 females; mean age, 15.8 years). The prevalence of GIRD was investigated for internal rotation differences of &gt;10° and total rotation motion of &lt;5°. Questionnaire items and ROM were compared between GIRD and non-GIRD patients, and sex differences in ROM were also presented. Of the participants, 38.2% (n = 47/123) had GIRD. The GIRD group showed a decrease in external rotation on the dominant side (p = 0.003, 1 - beta = 0.84), but this was not associated with a history of shoulder injury. Sex differences in shoulder ROM showed hypomobility in males and hypermobility in females. However, there was no association between shoulder injury and GIRD among adolescent players. There are sex differences in ROM, which should be considered in future studies.

Mechanism for shoulder pain and injury in elite badminton players

Purpose: to detect the mechanisms for shoulder pain and injury during forehand overhead stroke using the questionnaire and 2D video analysis. Methods and Materials: Participants were 48 university badminton players (aged 18-22) with national tournament level who had no current shoulder injuries. A questionnaire investigation and a forehand overhead clear test were performed. The angle of arm slot at the moment of hit was calculated from 2D videos analysis using Image J software. Data were compared between badminton players with shoulder problems and those without. Results: There were 6 badminton players reported a history of shoulder injury that all of them were offensive players. 11 badminton players (8 offensive players and 3 defensive players) reported present shoulder pain that offensive players showed 7.33 times more likely to sustain present shoulder pain than defensive players (OR = 7.33, 95%CI: 1.55-34.70, p = 0.007; Fisher’s Exact test: p = 0.012). Moreover, offensive players with present shoulder pain had significantly greater score of VAS (visual analog scale) than defensive players (74.0 mm ± 14.2 mm vs 44.6 mm ± 24.4 mm, p = 0.04). Significant differences of arm slot angle were found among badminton players with shoulder pain free, history of shoulder injury and present shoulder pain (35.74o ± 4.85o vs 42.90o ± 11.89 o vs 37.81o ± 6.40o, F = 3.27, p = 0.047). Conclusion: Offensive badminton players are more likely to suffer from shoulder injury and strong intensity of shoulder pain. Greater arm slot angle of hit phase might be the mechanism leading to shoulder problems in badminton players. For improving shoulder re-injury prevention and rehabilitation protocols, our findings should be taken into consideration by physiotherapists, physicians and coaches.

Decreased Trunk Rotation at Foot Contact in Professional Baseball Pitchers With Prior Conservatively Managed SLAP Tears: A Propensity Score–Matched Analysis

To compare kinematic and kinetic parameters between a cohort of fully recovered professional pitchers with prior shoulder injury treated conservatively and a cohort with no prior shoulder injury. Twenty-six fully recovered professional baseball pitchers with a history of shoulder injury treated conservatively pitched 8 to 10 fastball pitches using 3-dimensional motion capture (480 Hz). All shoulder injuries occurred within a 1- to 4-year time span from biomechanical evaluation and were severe enough to prevent pitchers from playing for between 1 and 12 months. These pitchers were propensity score matched by age, height, weight, handedness, and ball velocity to pitchers with no prior injury history (control) at a ratio of 1:4. We compared 21 kinematic and 11 kinetic parameters between groups using appropriate parametric testing. Subanalysis comparisons of pitchers with prior SLAP injury as well as rotator cuff tendinitis were also performed. SLAP tears (n= 11, 42.3%) were the most frequently reported injury, followed by rotator cuff tendinitis and/or shoulder impingement (n= 7, 26.9%). Compared with the control group, the 26 pitchers with prior injury showed no significant differences across the kinematic and kinetic factors. However, the SLAP tear subgroup did show significantly less trunk rotation at foot contact compared with controls (34.1° ± 4.9° vs 39.2° ± 10.2°, P= .0075). Fully recovered professional baseball pitchers with shoulder injuries treated conservatively showed no significant differences in kinetics or kinematics compared with their propensity score-matched counterparts, suggesting that shoulder injury alone may not greatly alter pitching mechanics. However, whereas prior groups have shown a decrease in trunk rotation at foot contact after surgical repair for SLAP tears, our study suggests that this kinematic change may alternatively originate with the injury itself. Understanding the cause of biomechanical adaptations by pitchers after injury can better aid clinicians and coaching staff in providing individualized and specific care to the throwing athlete.

Can the history of injury influence shoulder isokinetic torque parameters in volleyball players?

ABSTRACT The aim of the present study was to compare shoulder internal rotator and external rotator isokinetic parameters in concentric and eccentric contractions between volleyball players with and without a history of shoulder injury. Thirty male volleyball players participated of this study, divided into two groups: with a history of injury (WHI) in the dominant shoulder (11 athletes; age: 19.4 ± 3.6 years) and no history of injury (NHI) (19 athletes; age: 18.3 ± 2.9 years). The peak torque (PT) and concentric (Con) and eccentric (Ecc) PT angles in internal (IR) and external rotation (ER) at velocities of 60 and 180°/s were measured. The conventional (Con_ER:Con_IR), functional spiking (Ecc_ER:Con_IR), and cocking ratios (Ecc_IR:Con_ER) were calculated. No significant differences were found between groups for PT and PT angle, or for conventional, functional spiking, and cocking ratios. However, the spiking ratio was considered low (0.87) in the WHI group. Moreover, for the spiking ratio in the WHI group, PT at 60°/s occurred at different angles. We conclude that previous injury in shoulder did not affect the peak torque, as well as conventional, spiking or cocking ratio. However, the PT angles at 60°/s used to calculate the spiking ratio shifted due the prior injury.

The Relationship between Scapular Upward Rotation and Shoulder Internal and External Rotation Isokinetic Strength in Professional Baseball Pitchers.

This study aims to assess the relationship between scapular upward rotation (SUR) across varying humeral-elevation angles (HEAs) and shoulder isokinetic strength and ratio in professional baseball pitchers. The subjects were professional baseball pitchers (n = 16) without a history of shoulder injury in the last six months. The subject’s SUR angles were measured with the humerus elevated at HEAs of 0° (at rest), 60°, 90°, and 120° to the scapular plane. Shoulder isokinetic strength was evaluated for shoulder internal rotation (IR) and external rotation (ER) strength (PT%BW and TW%BW), and the ER/IR strength ratios were determined at 60, 120 and 180°/s using an isokinetic dynamometer. The SUR angle at an HEA of 0° was positively correlated with IR strength at 120°/s (r = 0.535) and 180°/s (r = 0.522). The SUR angle at an HEA of 60° was negatively correlated with the ER/IR strength ratios at 60°/s (r = −0.505) and 120°/s (r = −0.500). The SUR angle at an HEA of 90° was negatively correlated with the ER/IR strength ratios at 60°/s (r = −0.574; r = −0.554) and 120°/s (r = −0.521; r = −0.589) as well as with ER strength at 180°/s (r = −0.591, r = −0.556). The SUR angle at an HEA of 120° was negatively correlated with ER strength at 60°/s (r = −0.558), 120°/s (r = −0.504; r = −0.524), and 180°/s (r = −0.543) and the ER/IR strength ratio at 60°/s (r = −0.517). In this study, we found that the ratio of isokinetic strength between ER and IR became closer to the normal range on increasing the SUR angle. In particular, an HEA of 90°, which resembles the pitching motion, showed a clear relationship between SUR, shoulder ER, and the ratio of ER/IR isokinetic strength in professional baseball pitchers.

Thumb to spinous process is a false metric for glenohumeral internal rotation

The measurement of internal rotation by noting the maximal vertebral level reached by the patient's thumb behind their back is an established physical examination technique, as outlined in the American Shoulder and Elbow Surgeons Shoulder Assessment Form.7 The purpose of the present study is to correlate real-time glenohumeral internal rotation with thumb to spinous process movement to determine the accuracy of the technique. Healthy volunteers with no previous history of shoulder injury or symptoms were recruited from the local medical school population. Ultrasound probe was placed over the anterolateral shoulder, and relevant anatomy was identified. Internal rotation was evaluated by measuring displacement of the peak of the medial aspect of the bicipital groove relative to the anterior glenoid rim with the arm held in defined positions of progressively increasing internal rotation. The difference in displacement between arm positions was calculated and recorded. A total of 20 participants (11 women/9 men, aged 22-42 years) were recruited for measurement. A mixed-model repeated-measures analysis of variance was used. The most significant differences in displacement, and therefore internal rotation, were observed between the neutral and anterior superior iliac spine (0.21 ± 0.39 mm, P= .0269) and between the anterior superior iliac spine and peak iliac crest (0.26 ± 0.44 mm, P= .0163). After the peak iliac crest, there was no further statistically significant change in rotation. The present study suggests that most glenohumeral internal rotation occurs before reaching the arm behind the back. Although not directly studied, this supports the notion that the maximal vertebral level reached involves an interplay of various joint motions. While the thumb to spinous process maneuver remains a functional evaluation, our results suggest a different examination technique be used to more accurately test glenohumeral internal rotation.

Electromyographic Evaluation of the Shoulder Muscle after a Fatiguing Isokinetic Protocol in Recreational Overhead Athletes.

The goal of our study was to examine the muscle activity of the shoulder girdle after isokinetic fatigue, which may simulate muscle activities commonly occurring during specific sport-related activities in recreational overhead asymptomatic athletes. We hypothesized that exercise-induced fatigue, reported after isokinetic protocols, may cause a decrease in the median frequency (MF) of the upper trapezius (UT), infraspinatus (IS), and deltoid muscles. Twenty-four male overhead volleyball (n = 8), handball (n = 8), and tennis (n = 8) athletes participated in this study. All subjects were without shoulder injury history. The surface electromyography (SEMG) was collected on the right (dominant) side of the shoulder girdle muscles in the following order: UT, IS and anterior (DA), and posterior deltoideus (DP). The fatigue protocol consisted of three sets of 32 maximum isokinetic concentric contractions while performing shoulder internal and external rotation at an isokinetic speed of 120 o/s. The resultant difference in median frequency (ΔMF) values consistently dropped after the fatiguing tasks across all recorded muscles, in terms of the initial MF (MFINI = 65.1 ± 1.1 Hz) and final MF (MFFIN = 57.9 ± 0.9 Hz), and the main effect of time was significant (F(1,22) = 43.15, p < 0.001). MF values decreased mostly for IS (ΔMFIS = −9.9 ± 1.6 Hz) and DP (ΔMFPD = −9.5 ± 1.9 Hz) muscles, while DA and UT showed smaller changes (ΔMFDA = −6.9 ± 1.5 Hz) and (ΔMFUT = −3.2 ± 1.3 Hz). The results of our study show a meaningful contribution in determining increased fatigue of the shoulder girdle muscles during repeated isokinetic internal-external rotation protocols. We have also demonstrated a significant decrease in MF in all examined muscles, especially IS and DA.

Early Sport Specialization Linked to Throwing Arm Function and Upper Extremity Injury History in College Baseball Players.

Evidence suggests that shoulder and elbow injuries account for 31% to 37% of all National Collegiate Athletic Association (NCAA) baseball injuries, and up to 69% of NCAA baseball injuries are the result of noncontact and overuse mechanisms. Early sport specialization may contribute to the high rates of upper extremity injuries in college baseball players. Higher specialization by age 13 years would be associated with worse subjective throwing arm function and a greater history of shoulder and elbow injury. Cohort study. Level 2. Survey data were collected from college baseball players (N = 129) during midseason of the spring 2019 baseball season. Participants were stratified in low, moderate, and high specialization groups based on a 3-criteria sports specialization questionnaire. Participants' throwing arm function was measured using the Functional Arm Scale for Throwers and the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow questionnaires. Participants' history of a shoulder or elbow injury that resulted in missing ≥2 weeks of baseball activity at any point in their baseball career was also collected. The high specialization group reported worse subjective throwing arm function on the Functional Arm Scale for Throwers questionnaire than the low (P = 0.03) and moderate (P = 0.01) specialization groups. The high specialization group was over 5 times more likely to report a history of shoulder injury than the moderate (odds ratio [OR] = 5.42; 95% CI [1.71, 17.2]; P = 0.004) and low (OR = 5.20; 95% CI [1.87, 14.5]; P = 0.002) specialization groups, and over 3 times more likely to report a history of elbow injury than the moderate specialization group (OR = 3.77; 95% CI [1.05, 13.6]; P = 0.04). College baseball players that were highly specialized by age 13 years reported worse subjective throwing arm function and were more likely to have a history of upper extremity injury than players that were moderate or low specialization. Early specialization in baseball may be detrimental to long-term upper extremity health in college baseball players.

INFLUENCE OF LIMB DOMINANCE AND SHOULDER INJURY ON STRENGTH AND EXPLOSIVE FORCE IN US MARINES.

The specialized roles of many military personnel require specific skills and high physical demands, placing unique stresses on the shoulders and increasing risk of injury. As normal dominant/nondominant shoulder asymmetries have been established in military personnel, bilateral strength comparisons must be understood in context of daily physical demands to monitor patients' progress or readiness to return to duty. This study aims to assess bilateral differences in strength and explosive force in United States Marines with a history of dominant or nondominant shoulder pathology. Cross-Sectional. A total of 52 full-duty, male US Marines with a shoulder injury within the prior year participated. Bilateral isokinetic shoulder internal (IR) and external (ER) rotation strength, and peak force (Peak Force) and average rate of force production (Avg Rate) during an explosive push-up were collected. Dominant versus nondominant side data were independently examined within each group (DOM: dominant injury, NOND: nondominant injury). Comparison between DOM and NOND, as well as previously published CON (no history of shoulder injury) was also completed. NOND (n = 26) demonstrated significantly less IR (p < 0.001) and ER (p = 0.003) strength and Peak Force (p = 0.001) and Avg Rate (p = 0.047) on the injured side, while DOM (n = 26) demonstrated no bilateral differences in strength or push-up performance. Comparison between the three groups showed that NOND demonstrated significantly less ER strength than CON (p = 0.022). Military personnel demonstrate asymmetric strength patterns likely due to increased demand of the dominant shoulder. US Marines with a history of injury to the nondominant shoulder performed differently than those with a dominant side injury, presenting with both strength and push-up asymmetries. They also demonstrated significant ER strength deficits compared to CON. Common clinical practice and previous literature often compare injured and uninjured limbs or injured individuals to healthy controls, but further distinction of dominant or nondominant side may provide more accurate information needed to develop targeted treatment strategies. Recognizing unique occupational demands and how patients may present differently with dominant versus nondominant side shoulder injuries are important considerations for ensuring accurate assessment and effective individualized rehabilitation. 3.

Shoulder functional status in rugby union players with and without history of shoulder problems

ObjectivesTo assess the effects of (1) rugby union practice, (2) history of injury managed nonoperatively, and (3) history of injury managed operatively on shoulder functional status in male rugby union players. DesignCross sectional study. SettingClinical. Participants86 male athletes were assigned into four groups: multisport athletes, rugby union players without shoulder problems, with history of shoulder injury managed nonoperatively and with history of shoulder injury managed operatively. Main outcome measuresSI-RSI questionnaire, maximal isometric glenohumeral internal and external rotator strength, unilateral seated shot put test, upper quarter Y balance test. ResultsHealthy players presented higher internal (p = 0.03) and external (p = 0.04) rotator strength than multisport athletes. History of shoulder injury managed nonoperatively did not impair physical abilities but limited player’s psychological readiness (p < 0.001). After 4.5-months, shoulder stabilization surgery impaired maximal muscle strength and upper quarter body stability and mobility (p < 0.001 for all). ConclusionsThe shoulder functional status in rugby union player presented increased glenohumeral rotator strength when compared to non-collision sport athletes. In rugby union players, psychological concerns remained in the long-term after a shoulder injury managed nonoperatively, and psychological and physical readiness seemed not be reached at 4.5 months postoperatively to respond to rugby union practice demand.

Shoulder motion decreases as body mass increases in patients with asymptomatic shoulders

BackgroundHigher complication rates are reported after shoulder arthroplasty in obese patients. Understanding the effect of body mass index (BMI) on range of motion (ROM) in asymptomatic shoulders may be useful in evaluating clinical outcomes for patients of varying BMIs presenting with shoulder pathology. The purpose of this study is to investigate patient characteristics, in particular BMI, that may affect ROM outcomes after shoulder arthroplasty.MethodsIndividuals aged 18 years or older (mean 57.21 ± 16.27 years) were recruited with asymptomatic shoulder presentation and without history of shoulder injury. A total of 224 shoulders were grouped into 4 BMI categories, and ROM was measured with a goniometer. Analysis was performed between patient demographics and ROM.ResultsAnalyzed continuously, BMI negatively correlated with ROM for internal rotation (IR; r = −0.511, P < .01), forward elevation (FE; r = −0.418, P < .01), and external rotation (ER; r = −0.328, P < .01). ROM analyzed by BMI category revealed a dose effect of BMI vs ROM. Obese patients demonstrated a significant decrease in IR whereas morbidly obese patients had significant decreases for all ranges: IR (r = −0.469, P < .01), FE (r = −0.452, P < .01), and ER (r = –0.33, P < .01). Normal- and overweight patients revealed no significant correlations with ROM.ConclusionAs BMI is negatively correlated with ROM of the asymptomatic shoulder, patients with higher BMIs may be predisposed to diminished outcomes postoperatively. These baseline correlations will allow surgeons to make postoperative expectations and anticipate poorer outcomes of shoulder ROM in obese patients.

A Buford Complex in a Division I Collegiate American Football Player

A 19-year-old African-American male Division I collegiate American football player with no prior history of shoulder injury presented with right shoulder pain after making a tackle during a game. He was initially diagnosed with a rotator cuff strain with potential underlying labral pathology. Subsequent magnetic resonance imaging arthrogram showed no labral tearing, though a Buford complex was identified. A Buford complex is a normal anatomical labral variant where the anterior labrum is absent and the middle glenohumeral ligament is “cord-like” in structure. This case was managed conservatively since surgical intervention is only recommended if there is a secondary pathology to the shoulder (e.g., type II superior labrum anterior to posterior [SLAP] lesions). Clinicians should be aware of Buford complexes because they can predispose athletes to secondary injuries and can be managed successfully with a conservative rehabilitation approach in the absence of secondary pathology.

Comparison of shoulder range of motion, strength, and upper quarter dynamic balance between NCAA division I overhead athletes with and without a history of shoulder injury

ObjectiveTo determine differences in shoulder range of motion, strength, and upper quarter dynamic balance between collegiate overhead athletes with and without a history of a shoulder injury. DesignCross-sectional study. SettingAthletic training clinic. Participants58 overhead athletes who were fully participating in NCAA Division I overhead sports (baseball, softball, volleyball, and tennis) and free of any current shoulder injury were included. Participants were divided into a shoulder injury history group (n = 25) and uninjured group (n = 33). Participants in the shoulder injury history group had a previously resolved shoulder injury. Main outcome measuresActive range of motion assessments for shoulder internal rotation, external rotation, and horizontal adduction. Isometric strength assessments for shoulder IR and ER. The Upper Quarter Y-Balance Test. ResultsThe shoulder injury history group demonstrated a lower Upper Quarter Y-Balance Test mean score in the superolateral direction (p = .03, d = 0.56), but no group differences existed for other results (p > .05). ConclusionsOverhead athletes with a history of shoulder injury had worse upper quarter dynamic balance versus those without the history. From a clinical perspective, the findings may have significant implications for developing shoulder re-injury prevention and rehabilitation protocols in relation to their shoulder injury history.