Current concepts in the rehabilitation of the overhead throwing athlete

Repair of the Ulnar Collateral Ligament of the Elbow: Rehabilitation Following Internal Brace Surgery

Injuries to the elbow in athletes who play overhead sports, especially in baseball pitchers, continue to increase in frequency. The anterior band of the ulnar collateral ligament (UCL), the primary restraint to valgus stress, is commonly injured from throwing. Historically, such injuries have been treated with surgical reconstruction techniques, using a tendon autograft. A recently developed UCL repair procedure with an internal brace, utilizing collagen tape, is gaining popularity. The primary goal of this surgery is to enhance elbow joint stability while the ligament is healing and to allow earlier return to sport after UCL reconstruction. The rehabilitation program following UCL repair with internal brace progresses through a different time frame than after UCL reconstruction. The purpose of this commentary, based on our experience with more than 350 cases, including 79 patients with at least a 1-year postsurgical follow-up, was to describe and provide the rationale for the rehabilitation process following UCL repair with internal brace. J Orthop Sports Phys Ther 2019;49(4):253-261. doi:10.2519/jospt.2019.8215.

Hip, Trunk, and Shoulder Rotational Range of Motion in Healthy Japanese Youth and High-school Baseball Pitchers

Objective

The rotational range of motion (ROM) in the upper extremities, trunk, and lower extremities is important for throwing motion. However, unlike for the shoulders, the differences relating to age and throwing-side in trunk and lower extremity ROMs in baseball pitchers are unknown. This study examined the effects of age and dominance on the ROMs of the trunk and upper and lower extremities.

Methods

The study included 356 young baseball pitchers aged 9-17 years who participated in off-season baseball camps. The subjects comprised 155 youth pitchers (aged 9-14 years) and 201 high-school pitchers (aged 15-17 years) who were able to throw at full force without pain. The neck, shoulder, trunk, and hip rotational ROMs on the dominant and non-dominant side were measured by well-trained physical therapists. The differences between throwing sides and between age groups were examined using two-way analysis of variance.

Results

Shoulder external rotation on the dominant side was greater than that on the non-dominant side. Shoulder external and internal rotational ROMs were maintained regardless of age, whereas the trunk rotational ROM significantly increased with age.

Conclusions

The effects of age and dominance on ROMs of the neck, trunk, and upper and lower extremities in Japanese youth and high-school baseball pitchers were clarified. These data could be used as a specific reference and as target values for the rehabilitation of throwing injuries in young athletes.

Effects of 3 Infraspinatus Muscle Strengthening Exercises on Isokinetic Peak Torque and Muscle Activity

CONTEXT

The infraspinatus muscle plays a particularly important role in producing primary external rotation (ER) torque and dynamic stability of the shoulder joint. Previous studies have reported that prone external rotation with horizontal abduction (PER), side-lying wiper exercise (SWE), and standing external rotation (STER) were effective exercises for strengthening the infraspinatus. However, we do not have enough knowledge about changes in muscle strength and dynamic muscle activity in each exercise under dynamic conditions.

OBJECTIVE

To compare the ER muscle strength, muscle activity among exercise methods and between muscle contraction types during 3 different exercises.

DESIGN

Repeated measures design in which ER muscle strength and muscle activities data were collected from subjects under 3 exercise conditions.

SETTING

Outpatient clinic.

PARTICIPANTS

A total of 15 healthy men with no shoulder, neck, or upper-extremity pain were participated.

INTERVENTION

The subjects performed 3 different exercises randomly in concentric and eccentric using a Biodex dynamometer at an angular velocity of 60°/s.

MAIN OUTCOME MEASURES

The ER peak torque (PT) data was collected and surface electromyography was used to measure the activity of the infraspinatus and posterior deltoid muscles and infraspinatus to posterior deltoid muscle activity ratio.

RESULTS

There was significant main effect for muscle contraction type in ER PT (P < .05). The concentric PT was greater during PER (P < .05) and SWE (P < .05) compared with eccentric. The main effect for exercise was found in ER PT and muscle activity (P < .05). The ER PT and infraspinatus muscle activity were the largest increased during PER whereas the lowest during STER in both concentric and eccentric (P < .05).

CONCLUSION

The results of this study suggest that PER is an exercise for strengthening the infraspinatus muscle effectively.

Effects of deceleration-focused exercise strategies on shoulder range of motion and throwing velocity in baseball and softball athletes

This study examined the effects of deceleration-focused exercises on shoulder range of motion and throwing velocity in both softball and baseball players. Volunteers included 28 Division III William Paterson University baseball and softball athletes (18 females and 10 males), who were evenly distributed across two groups both undertaking 14 sessions of either resistance band or handheld medicine ball exercises (band vs. ball group). A pre-test and post-test measured participants' best active internal/external shoulder rotation and best throwing velocity at a target 40 ft away. A two-tailed, independent t-test showed no significant differences in velocity, internal rotation or external rotation (p < 0.01) between the band and ball groups. However, the average change in velocity in the ball group was double that of the band group (1.50 ± 2.06 m/s versus 0.73 ± 2.24 m/s). For change in both internal and external rotation the band group (2.86 ± 5.27° and 3.29 ± 3.87°, respectively) was greater than the ball mean (1.93° ± 3.32° and 1.29 ± 6.52°, respectively). These findings suggest that overhead athletes aiming to increase throwing velocity can benefit from performing deceleration training with weighted balls whereas resistance bands appear to improve shoulder rotation.

Electromyographic analysis of selected shoulder muscles during rehabilitation exercises

BACKGROUND

Overhead work-activities and repetitive use of arm in occupational tasks are known risk factors to cause shoulder injury that often develops to functional disability. Rehabilitation exercises (REs) are capable of slowing this development.

OBJECTIVE

The main objective of the present work is to experiment with common REs and to identify those which produce significant integrated electromyography (iEMG) activation of selected shoulder muscles namely, posterior deltoid, infraspinatus, teres minor, upper trapezius, middle trapezius and lower trapezius.

METHODS

  Ten healthy male occupational workers, exposed to the risk of shoulder injury, performed six REs while iEMG activities of concerning muscles are recorded using Biopac MP 150 system. REs are cross-examined statistically to select those which yield higher iEMG activations.

RESULTS

Results indicate that upper trapezius presents the highest iEMG activity in exercise 6 (standing ER at 90∘ abduction and 90∘ elbow flexion). Middle trapezius and lower trapezius show highest activation in exercise 1 (prone horizontal abduction at 90∘ with full external rotation with thumb right up). Also, posterior deltoid, infraspinatus, and teres minor have the highest iEMG activity in this exercise.

CONCLUSIONS

Results provide basic information to select appropriate rehabilitation programs for occupational workers exposed to the risk of shoulder injury.

Medial elbow anatomy: A paradigm shift for UCL injury prevention and management

To improve the management outcomes and diagnostic accuracy of the ulnar collateral ligament (UCL) injury, the anatomy of the medial side of the elbow joint is necessary to be understood in terms of the periarticular surroundings rather than the specific ligaments. The aim of this study was to anatomically clarify the medial side of the elbow joint in terms of the tendinous structures and joint capsule. We conducted a descriptive anatomical study of 23 embalmed cadaveric elbows. We macroscopically analyzed the relationship between the flexor pronator muscles (FPMs) and the joint capsule in 10 elbows, histologically analyzed in 6 elbows, and observed the bone morphology through micro computed tomography in 7 elbows. The two tendinous septa (TS) were found: between the pronator teres (PT) and flexor digitorum superficial (FDS) muscles, and between the FDS and flexor carpi ulnaris (FCU) muscles. These two TS are connected to the medial part of the brachialis tendon, deep aponeurosis of the FDS, and FCU to form the tendinous complex, which linked the humeroulnar joint and could not be histologically separated from each other. Moreover, the capsule of the humeroulnar joint under the tendinous complex had attachment on the ST of 7 mm width. The two TS, the brachialis tendon, the deep FDS and FCU aponeuroses, and the joint capsule linked the humeroulnar joint. These anatomical findings could lead to a paradigm shift in the prevention, diagnosis, and treatment of UCL injuries in baseball players. Clin. Anat. 32:379–389, 2019. © 2018 The Authors. Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.

Assessment of ultrasonography as a diagnostic tool in shoulder pain and alterations in glenohumeral range of motion in tennis players

INTRODUCTION

Shoulder pain and alterations in the range of motion are common disorders in tennis players. However, the relation between shoulder structures and these conditions is unknown.

AIM

To evaluate whether, using ultrasonography, one can identify tennis players with shoulder pain and those having specific changes of the range of rotation of the glenohumeral joint.

MATERIAL AND METHODS

A total of 66 subjects were assessed through examination of the range of rotation of the glenohumeral joint and ultrasonography.

RESULTS

The study group consisted of 37 people with shoulder pain (24.2 ±8.6 years) and the control group included 29 subjects without shoulder pain (21.9 ±10.8 years). The prevalence of pathologies of the supraspinatus (SSP), infraspinatus (ISP) or subscapularis (SSC) was significantly higher in the study group than in the control group (p = 0.044) but solely for the combined pathologies. The incidence rate of pathological shoulder changes (the SSP, ISP, SSC and the subacromial bursa) was not correlated with the ranges of rotations or intensity of pain. Glenohumeral internal rotation deficit (GIRD), total rotational motion (TROM) deficit and external rotation deficiency (ERD) were independent of pathological shoulder changes, except the significantly higher prevalence of SSP pathologies among subjects with ERD.

CONCLUSIONS

Ultrasonography could be helpful in identifying tennis players with painful shoulder having rotator cuff pathologies. However, the ability of the method to identify players having specific changes of the range of rotation of the glenohumeral joint is limited, with the exception of tennis players with ERD having SSP pathologies.

Youth Baseball Coach Awareness of Pitch Count Guidelines and Overuse Throwing Injuries Remains Deficient

BACKGROUND

Baseball is one of the most popular youth sporting activities. Youth pitchers remain at high risk for shoulder and elbow overuse injuries despite well-established recommendations on pitch count limits. The purpose of this investigation was to conduct surveys of youth baseball coaches evaluating the current state of understanding and compliance with youth pitch count guidelines and risk factors for overuse injuries.

METHODS

A total of 82 youth baseball coaches in surrounding suburban areas outside 2 separate Midwestern metropolitan cities were asked to answer an anonymous 13-question survey. Survey questions solicited demographic information of youth athletes coached, while assessing for incidence, knowledge of, and compliance with established recommendations on pitch count limits and upper extremity overuse injuries in youth pitchers.

RESULTS

In total, 61 of 82 (74%) coaches returned surveys. The majority of coaches reported coaching male athletes (89%, n=54) primarily between the ages of 11 to 12 years (51%, n=31). A total of 56% (n=34) of coaches reported "always" keeping track of pitch counts; however, 92% (n=56) reporting not keeping track of pitches based on established recommendations by the American Sports Medicine Institute, whereas 56% were noncompliant with age appropriate pitch count recommendations as established by the 2006 US Baseball Medical and Safety Advisory Committee. Only 13% (n=8) of coaches were able to correctly identify risk factors for overuse injuries while acknowledging the necessity of off-season strengthening. Thirty-eight percent (n=23) of coaches reported sitting out an athlete because of overuse injury, with the highest rates found in those coaching the youngest (≤8 and younger) and oldest (≥17 and older) age groups. Meanwhile, 15% (n=9) of coaches were noncompliant with age-based recommendations against throwing breaking pitches.

CONCLUSIONS

Knowledge regarding pitch count guidelines established to prevent overuse injuries to the shoulder and elbow in youth pitchers remains deficient in the cohort of coaches surveyed.

LEVEL OF EVIDENCE

Level IV-Case Series.

The Utilization of Interval Throwing Programs in the Physical Therapy Setting: A Cross-Sectional Survey

Context: Interval throwing programs (ITPs) have long been used in the physical therapy setting to aid in the safe and efficacious return to sport for an overhead athlete. However, the overall utilization and variation of ITPs are unknown in the physical therapy setting leading to potential inconsistencies in treatment paradigms. Objective: To determine if differences in practice patterns exist among active physical therapists of various experience levels with regard to years of experience and advanced certifications. Design: Cross-sectional survey study. Participants: A total of 133 licensed physical therapists consented to participate in an online-based survey. Experience groups were delineated based on years of practice (0-1, 1-5, 6-15, and 15+) and possession of advanced certification. Main Outcome Measures: For ranking-based data, a generalized linear mixed model was repeated across criteria response with a Bonferroni post hoc adjustment for pairwise comparisons made within and between groups (α < .05). For degree-based questions, chi-square analysis was used to compare response frequencies for options provided within each question. Results: A 76.7% response rate was achieved with 102 out of the 133 consenting individuals completed the survey. Significant differences (P < .05) were found with responses to both ranking-based and degree-based questions. However, across all groups, physical therapists agreed that throwing mechanics and customized ITP implementation were important for a successful return to throwing. Conclusions: There are inherent differences in ITP prescription among physical therapists with dissimilar experience levels. The possession of advanced certifications and years of practice seem to play a role in how interval programs are prescribed to overhead-throwing athletes. This study helps to identify differences in current physical therapy approaches toward the later stages of rehabilitation for throwing athletes. Further research should identify areas of improvement in physical therapist education as well as appropriate ITP prescription parameters to optimize care and treatment for this patient population.

Effective stretching position for the supraspinatus muscle evaluated by shear wave elastography in vivo

BACKGROUND

Stretching is useful for increasing flexibility in clinical and athletic situations. Although several authors have recommended various stretching techniques for the supraspinatus muscle, there is no consensus on the effective stretching position owing to a lack of quantitative analysis in vivo. This study used ultrasonic shear wave elastography in vivo to verify the effective stretching positions for the supraspinatus muscle.

METHODS

The study participants were 15 healthy male volunteers. The shear elastic modulus, used as the index of supraspinatus muscle elongation, was computed using ultrasonic shear wave elastography. The shear elastic modulus was measured at neutral position and maximum internal rotation in 9 positions: 0° elevation, 90° abduction, 90° flexion, maximum extension, maximum horizontal adduction at 45° and 90° elevation, and maximum horizontal abduction at 20°, 45°, and 90° elevation.

RESULTS

The shear elastic moduli were significantly greater in maximum internal rotation at maximum horizontal abduction with 45° and 90° elevation and maximum internal rotation at maximum extension than those in the other positions. There were no significant differences in the shear elastic moduli among these 3 positions.

CONCLUSIONS

This study demonstrated that maximum internal rotation at maximum extension, maximum internal rotation at maximum horizontal abduction with 90° elevation, and maximum internal rotation at maximum horizontal abduction with 45° elevation are effective stretching positions for the supraspinatus muscle.

Effects of a six-week weighted-implement throwing program on baseball pitching velocity, kinematics, arm stress, and arm range of motion

BACKGROUND

Weighted-baseball training programs are used at the high school, collegiate, and professional levels of baseball. The purpose of this study was to evaluate the effects of a six-week training period consisting of weighted implements, manual therapy, weightlifting, and other modalities on shoulder external rotation, elbow valgus stress, pitching velocity, and kinematics.

HYPOTHESIS

A six-week training program that includes weighted implements will increase pitching velocity along with concomitant increases in arm angular velocities, joint kinetics, and shoulder external rotation.

METHODS

Seventeen collegiate and professional baseball pitchers (age range 18-23, average: 19.9 ± 1.3) training at Driveline Baseball were evaluated via a combination of an eight-camera motion-capture system, range-of-motion measurements and radar- and pitch-tracking equipment, both before and after a six-week training period. Each participant received individualized training programs, with significant overlap in training methods for all athletes. Twenty-eight biomechanical parameters were computed for each bullpen trial, four arm range-of-motion measurements were taken, and pitching velocities were recorded before and after the training period. Pre- and post-training period data were compared via post-hoc paired t tests.

RESULTS

There was no change in pitching velocity across the seventeen subjects. Four biomechanical parameters for the holistic group were significantly changed after the training period: internal rotational velocity was higher (from 4,527 ± 470 to 4,759 ± 542 degrees/second), shoulder abduction was lower at ball release (96 ± 7.6 to 93 ± 5.4°), the shoulder was less externally rotated at ball release (95 ± 15 to 86 ± 18°) and shoulder adduction torque was higher (from 103 ± 39 to 138 ± 53 N-m). Among the arm range of motion measurements, four were significantly different after the training period: the shoulder internal rotation range of motion and total range of motion for both the dominant and non-dominant arm. When the group was divided into those who gained pitching velocity and those who did not, neither group showed a significant increase in shoulder external rotation, or elbow valgus stress.

CONCLUSIONS

Following a six-week weighted implement program, pitchers did not show a significant change in velocity, joint kinetics, or shoulder external rotation range of motion. When comparing pitchers who gained velocity versus pitchers who did not, no statistically significant changes were seen in joint kinetics and shoulder range of motion.

Effect of Increased Scapular Internal Rotation on Glenohumeral External Rotation and Elbow Valgus Load in the Late Cocking Phase of Throwing Motion

BACKGROUND

Scapular dyskinesis among throwers is thought to affect kinetic chain function and increase the load demands on the shoulder and/or elbow. However, the biomechanical relationship between scapular orientation and elbow valgus load, which is associated with ulnar collateral ligament (UCL) injury, has not been determined.

PURPOSE

To evaluate the effect of increased scapular internal rotation (IR) and glenohumeral external rotation (GHER) on elbow valgus load in a static simulation of the late cocking phase of throwing.

STUDY DESIGN

Controlled laboratory study.

METHODS

Seven fresh-frozen male cadaveric upper extremities were used with a custom testing system to simulate the late cocking phase. First, the authors evaluated the effect of increasing scapular IR on maximum GHER and forearm angle (forearm axis relative to the ground). Each parameter was evaluated at 20° to 40° (5° increments) of scapular IR by applying 2.2-N·m external rotation torque to the humerus and 0.75-N·m valgus torque to the forearm. Next, to evaluate elbow valgus stability, the humerus was locked in maximal GHER at 40° of scapular IR, and sequentially increasing torque (0.75-7.5 N·m by 0.75-N·m increments) was applied to the forearm. Valgus angle and joint gap were evaluated at each torque.

RESULTS

Increases in scapular IR ≥5° significantly decreased GHER ( P < .01). With increasing valgus torque, forearm angle also increased linearly ( R² = 0.85, P < .001). To compensate for the GHER deficit at 40° of scapular IR, a linear regression model showed that 25.3 N·m of valgus torque would be necessary to reach the original forearm position. In the intact condition, applying elbow valgus torque ≥5.25 N·m significantly increased valgus angle and the joint gap ( P < .01).

CONCLUSION

Increased scapular IR significantly decreased GHER. Compensation for the GHER deficit significantly increased the elbow valgus load required to reach the same forearm position.

CLINICAL RELEVANCE

Increased scapular IR may increase the risk of elbow UCL injury among throwing athletes.

Changes in Throwing Arm Mechanics at Increased Throwing Distances During Structured Long-Toss

BACKGROUND

Elbow injuries among adolescent baseball players have been outpacing those of college and professional players. In attempts to prevent injuries and maximize return-to-play potential following injury, attention has been focused on "return to throw" programs, which include long-toss throws. Because the few studies that were conducted on long-toss throwing focused primarily on college-aged athletes, it is not known what type of load is incurred at the elbow during interval throwing progression among high school baseball players.

PURPOSE

To quantify the change in arm slot, arm speed, shoulder external rotation, and elbow varus torque across increasing throwing distances within a given athlete.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Ninety-five high school baseball players performed a long-toss protocol while wearing an inertial sensor and sleeve. Each participant was tested for 5 throws at distances of 9 m, 18 m, 27 m, 37 m, and 46 m. Linear mixed-effects models and likelihood ratio tests were used to estimate the within-participant relationship between throw distance and arm slot, arm speed, shoulder external rotation, and elbow varus torque.

RESULTS

Arm slot ( P < .01), arm speed ( P < .01), shoulder external rotation ( P < .01), and elbow varus torque ( P < .01) were significantly associated with long-toss throw distance. As the throw distance increased, there was an increase in arm speed and shoulder external rotation and a decrease in arm slot for each distance. However, elbow varus torque increased with each distance up to 37 m and then remained the same at 46 m.

CONCLUSION

The use of longer distances for conditioning and rehabilitation may be beneficial in increasing shoulder range of motion and arm speed; however, precaution needs to be taken, as throwing longer distances are accompanied by an increase in arm rotation, arm speed, and elbow torque, with a decrease in arm slot.

CLINICAL RELEVANCE

Return-to-throw programs have been utilized by sports medicine clinicians and coaches to help guide a player during rehabilitation. These programs involve throwing at increased efforts through increased distances with no immediate feedback on elbow stress. This investigation describes arm biomechanical changes during submaximum interval throwing and demonstrates a tool that can be utilized to measure arm stress in real time for clinicians and athletes progressing through an interval throwing program.

Differentiation of bony and soft-tissue adaptations of the shoulder in professional baseball pitchers

BACKGROUND

Baseball pitching places tremendous forces on the arm, which may lead to structural tissue adaptations that are represented by changes in rotational range of motion (ROM). These adaptations often include both bony and soft tissue; however, the contribution of each tissue to the change in motion is not always clinically attainable. The purposes of this study were to determine the adaptations of ROM, bone, and soft tissue bilaterally and to examine the correlation between clinical ROM and humeral retroversion (HR)-corrected ROM. We hypothesized that glenohumeral internal rotation (IR) and total motion would be decreased and glenohumeral external rotation (ER), posterior capsule thickness (PCT), and HR would be increased in the dominant arm; that HR-corrected ROM would be significantly different than clinical ROM; and that HR-corrected ROM would be correlated with total motion difference.

METHODS

Thirty professional baseball pitchers participated in this study. HR, PCT, and glenohumeral IR and ER were evaluated in the dominant and nondominant shoulders of each subject.

RESULTS

The dominant arm exhibited significantly more retroversion, ER, and PCT than the nondominant arm. The dominant arm also had significantly less IR and total motion than the nondominant arm. The total ROM difference was significantly correlated with both HR-corrected glenohumeral IR deficit and ER gain.

CONCLUSION

HR-corrected glenohumeral IR deficit and ER gain may more accurately reflect the contribution of soft-tissue changes to ROM. Unfortunately, measurement of HR is not always clinically attainable, making clinical management difficult.

Superior Labral Anterior to Posterior Tear Management in Athletes

Background:

The diagnosis and treatment of Superior Labrum Anterior to Posterior (SLAP) tears have been evolving and controversial. The lack of clear diagnostic criteria on physical examination, Magnetic Resonance Imaging (MRI), and arthroscopic evaluation clouds the issue. The high rate of MRI diagnosed SLAP lesions in the asymptomatic population of athletes and non-athletes warrants consideration when planning treatment for those with shoulder pain.

Objective:

To provide information on the evaluation, diagnosis and management of SLAP tears in athletes.

Methods:

The results of a structured non-operative rehabilitation program are discussed and compared to traditional surgical techniques. The evolution of the author’s treatment algorithm is presented. Results: The successful return to overhand throwing is more common with non-operative treatment than with surgical.

Conclusion:

A rehabilitation program focused on stretching the posterior capsule and correcting scapular posture is more successful than surgery for most throwers with SLAP lesions.

Three-dimensional kinematic analysis of glenohumeral, scapular, and thoracic angles at maximum shoulder external rotation associated with baseball shadow pitching: comparison with normal pitching

[Purpose] The glenohumeral, scapular, and thoracic angles at maximum shoulder external rotation during shadow pitching were evaluated and compared with those observed during normal pitching. [Participants and Methods] Our study included 13 healthy males with experience in pitcher activity. All participants performed both, shadow pitching using a towel and normal pitching using a ball. The external rotation of the glenohumeral joint, scapular posterior tilting, and thoracic extension angles in the cocking phase were measured using a 3-dimensional motion analysis system. The ratios of the glenohumeral external rotation angle to the scapular posterior tilting and/or thoracic extension angle were calculated to evaluate the contribution of the scapulothoracic joint at maximum external rotation during throwing/pitching activity. [Results] The glenohumeral external rotation angle at maximum shoulder external rotation was significantly smaller during shadow pitching than during normal pitching. The ratio of the glenohumeral external rotation angle to the scapular posterior tilting and/or thoracic extension angle showed no statistically significant difference. [Conclusion] We conclude that shadow pitching can reduce the external rotation motion of the glenohumeral joint compared to that during normal pitching and might be a useful pre-throwing program beneficial in the rehabilitation of those presenting with throwing injuries.

Effects of 4-week self-cross body stretching with scapular stabilization on shoulder motions and horizontal adductor strength in subjects with limited shoulder horizontal adduction: cross body stretching with stabilization

BACKGROUND

Posterior shoulder tightness is related to shoulder conditions such as shoulder impingement and limited shoulder horizontal adduction (SHA). The purpose of this study was to compare the effects of self-cross body stretching (CBS) with and without scapular stabilization (SS) on SHA and shoulder internal rotation (SIR) range of motion (ROM) and shoulder horizontal adductor strength (SHAS) in subjects with limited SHA.

METHODS

Twenty-six subjects (14 males, 12 females) with limited SHA was participated in this study. The SS group and without stabilization (WS) group were assigned randomly. The SS group performed self-CBS with SS by applying belt just under the subject's axilla. The subjects were asked to perform self-CBS 4 times a week for 4 weeks. SHA and SIR RM were measured by Clinometer smartphone application, and SHAS by hand-held dynamometer before and after 4-week self-CBS.

RESULTS

2 × 2 mixed analysis of variance (ANOVA) was used to identify the significance. If there was an interaction effect, t-test was used to confirm the simple effect. There was a significant interaction in SHA ROM and SHAS. The post-test value of SHA ROM was significantly greater in SS group than WS group (P<0.0125). In SHAS, there was no significant difference between groups (P>0.0125).

CONCLUSIONS

SS during self-CBS could enhance to improve SHA, SIR ROM, and SHAS in individuals with limited SHA.

Differences in Glenohumeral Joint Rotation and Peak Power Output Between Super League and Championship Rugby League Players

Haines, MR. Differences in glenohumeral joint rotation and peak power output between Super League and Championship Rugby League players. J Strength Cond Res 32(6): 1685-1691, 2018-Rugby league is a high-intensity sport with large impact forces sustained during play, resulting in high prevalence of shoulder injury. Consequently, shoulder strength and player power are important considerations for injury prevention and performance. Additionally, professional teams regularly compete against semiprofessional teams, where differences in physical conditioning could be marked. The aim of this study was to test for differences in glenohumeral joint rotation and peak power between a professional Super League (SL) and semiprofessional Rugby League Championship (RLC) teams. A cross-sectional analysis was used to test 25 SL and 24 RLC players during preseason training. Isokinetic dynamometry, at 240°·s for concentric and eccentric actions was used to assess glenohumeral rotation. Peak power was determined using a maximal 30-second cycle ergometer test. Selective muscular development of the internal rotators without concomitant external rotator strength was evident in the SL team but not the RLC team. Internal rotation peak torque was higher for the SL club for concentric (∼24%) and eccentric (∼16%) muscle actions (p ≤ 0.05), and this contributed to a lower ipsilateral reciprocal muscle group ratio (external to internal concentric) for the SL team compared with the RLC team (∼47% and ∼60% respectively; p ≤ 0.05). Peak power output was also higher for the SL team (1,409 ± 153 vs. 1,273 ± 159 W; p ≤ 0.05). The results highlight a mismatch in the physical conditioning of SL and RLC players with implications for practitioners to design strength and conditioning programs that minimize the risk of injury while optimizing performance.

Outcomes and Return to Sport After Ulnar Collateral Ligament Reconstruction in Adolescent Baseball Players

Background:

The number of ulnar collateral ligament (UCL) reconstructions in adolescent athletes has increased over the past 2 decades. Clinical results in this population have not been well studied.

Purpose/Hypothesis:

The purpose of this study was to evaluate the outcomes and return to sport after UCL reconstruction in a large group of adolescent baseball players. We hypothesized that excellent clinical outcomes and high rates of return to sport would be observed in this population at a minimum 2-year follow-up.

Study Design:

Case series; Level of evidence, 4.

Methods:

We reviewed 140 adolescent (aged ≤19 years) baseball players who underwent UCL reconstruction with the American Sports Medicine Institute (ASMI) technique by a single surgeon. Medical records were reviewed for patient demographics, injury characteristics, operative details, and surgical complications. Patient-reported outcomes were assessed using the Conway scale, the Andrews-Timmerman (A-T) score, the Kerlan-Jobe Orthopaedic Clinic (KJOC) score, and a 0- to 100-point subjective scale for elbow function and satisfaction. Return to sporting activity was assessed using a custom-designed questionnaire.

Results:

The mean age at the time of surgery was 18.0 years (range, 13-19 years), and the mean follow-up was 57.9 months (range, 32.4-115.4 months). Over half (60%) of patients were high school athletes. The mean duration of symptoms before surgery was 6.9 months (range, 0.5-60.0 months). Partial tears were identified in 57.9% of patients, and 41.3% of patients had preoperative ulnar nerve symptoms. Graft type included the ipsilateral palmaris in 77.1% of patients. Concomitant procedures were performed in 25% of patients. Outcomes on the Conway scale were “excellent” in 86.4% of patients. The mean A-T and KJOC scores were 97.3 ± 6.1 and 85.2 ± 14.6, respectively. Mean patient satisfaction was 94.4. Overall, 97.8% of patients reported returning to sport at a mean of 11.6 months (range, 5-24 months), and 89.9% of patients returned to sport at the same level of competition or higher. A total of 11.6% of patients went on to play professional baseball.

Conclusion:

UCL reconstruction with the ASMI technique is an effective surgical option in adolescents, with excellent outcome scores. At a minimum of 2-year follow-up, nearly 90% of patients returned to their preinjury level of sport.

Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction

BACKGROUND

Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis.

PURPOSE

To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo.

STUDY DESIGN

Controlled laboratory study.

METHODS

Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition.

RESULTS

The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137).

CONCLUSION

Medial elbow joint space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous research in vitro.

CLINICAL RELEVANCE

Muscle activation of the upper extremity limits the medial elbow joint space, suggesting that injury prevention programs for throwing athletes should incorporate exercises for the elbow, wrist, and hand to limit excessive medial elbow joint space gapping during activities that create high valgus load.

Glenohumeral internal rotation deficit in throwing athletes: current perspectives

Glenohumeral internal rotation deficit (GIRD) is an adaptive process in which the throwing shoulder experiences a loss of internal rotation (IR). GIRD has most commonly been defined by a loss of >20° of IR compared to the contralateral shoulder. Total rotational motion of the shoulder is the sum of internal and external rotation and may be more important than the absolute value of IR loss. Pathologic GIRD has been defined as a loss of IR combined with a loss of total rotational motion. The leading pathologic process in GIRD is posterior capsular and rotator-cuff tightness, due to the repetitive cocking that occurs with the overhead throwing motion. GIRD has been associated with numerous pathologic conditions, including posterior superior labral tears, partial articular-sided rotator-cuff tears, and superior labral anterior-to-posterior tears. The mainstay of treatment for patients with GIRD is posterior capsular stretching and strengthening to improve scapular mechanics. In patients who fail nonoperative therapy, shoulder arthroscopy can be performed. Arthroscopic surgery in the high-level throwing athlete should be to restore them to their functional baseline with the minimum amount of intervention possible.

Shoulder Dynamic Control Ratio and Rotation Range of Motion in Female Junior Elite Handball Players and Controls

OBJECTIVE

To compare glenohumeral range of motion and shoulder rotator muscle strength in healthy female junior elite handball players and controls.

DESIGN

Cross-sectional case-control study.

SETTING

Sports medical center.

PARTICIPANTS

Forty elite female handball players and 30 controls active in nonoverhead sports participated in this study.

MAIN OUTCOME MEASURES

Passive external rotator (ER), internal rotator (IR), and total range of motion (TROM) of the dominant and nondominant arm were examined with a goniometer. An isokinetic dynamometer was used to evaluate concentric and eccentric rotator muscle strength at 60 and 120 degrees/s with dynamic control ratio (DCR = ERecc:IRcon) as the main outcome parameter.

RESULTS

Except for the ER range of motion in the nondominant arm, no significant differences were found between groups for IR, ER of the dominant arm, and the TROM. Within the handball group, the side-to-side difference for IR of the dominant arm was -1.4 degrees. The ER and the TROM of the dominant arm were significantly larger, 6.3 and 4.9 degrees, respectively. For both groups, the DCR values were above 1 and no significant differences were found between the dominant and nondominant arm. The DCR values in the handball group were significantly lower than in the control group.

CONCLUSIONS

Based on the adopted definitions for muscle imbalance, glenohumeral internal range of motion deficit and TROM deficit our elite female handball players seem not at risk for shoulder injuries. Prospective studies are needed to support the belief that a DCR below 1 places the shoulder at risk for injury.

Stretching Exercises for Subacromial Impingement Syndrome: Effects of 6-Week Program on Shoulder Tightness, Pain, and Disability Status

Context: Increasing soft tissue flexibility and joint mobility is one of the important aims of studies to treat subacromial impingement syndrome (SIS). Objective: The aim of this study was to investigate the effects of a stretching program on posterior capsule tightness, pectoralis minor tightness, pain severity, and disability status in SIS. Design: Single-group pretest posttest design. Setting: University outpatient clinic. Participants: 18 participants diagnosed with SIS (34.8±9.4 y, symptoms duration 5.8±4.9 months) were included in the study. Intervention: The 6-week self-stretching program for pectoralis minor, posterior capsule, levator scapula, and latissimus dorsi was performed. Main Outcome Measures: Posterior capsule tightness, pectoralis minor tightness, pain severity (visual analog scale), and self-reported shoulder-related pain and disability status (Shoulder Pain and Disability Index) were used to assess changes in flexibility and symptoms. Results: Comparisons showed that there was significantly less posterior capsule and pectoralis minor tightness, less pain severity on activity and at night, and a lower disability score reported after the 6-week stretching program (P < 0.05). There was no statistically significant difference in pain severity at rest after the 6-week stretching program (P > 0.05). Conclusions: The findings of the study showed that flexibility, pain severity, and disability gains can be achieved with a 6-week stretching exercise training for participants with SIS. Therefore, shoulder girdle stretching exercises should be recommended early in shoulder rehabilitation program.

Comparative outcomes of extracorporeal shockwave therapy for shoulder tendinitis or partial tears of the rotator cuff in athletes and non-athletes: Retrospective study

BACKGROUND

Refractory shoulder tendinitis or partial thickness rotator cuff tears (PTRCTs) are common findings in overhead athletes. Previous studies have examined the effectiveness of extracorporeal shockwave therapy (ESWT) for shoulder tendinitis.

MATERIALS AND METHODS

In the current study, we recruited 36 shoulders and performed a comparison between the professional athletes (13 shoulders, athletic group; AG) and the non-athletic population (23 shoulders, non-athletic group, NAG) with PTRCTs or shoulder tendinitis of the shoulder after ESWT. Patients with symptomatic tendinitis of the shoulder with or without a partial tear of the rotator cuff tendon and failed oral medication and physical therapy for more than 3 months were treated with electrohydraulic mode of ESWT. All patients that met the inclusion criteria were categorized into two groups according to their pre-treatment activity level.

RESULTS

We found that NAG exhibited significant aging and degenerative change around the glenohumeral joint and subacromial space. After ESWT treatment, the patients in AG were with 53.8% high satisfaction rating and patients in NAG were 52.1% by one-year followed up.

CONCLUSION

The results showed ESWT was equally effective treatment in both AG and NAG. In light of its efficacy and less-invasive nature, we suggest ESWT can be used to treat athletes with refractory tendinitis or PTRCTs before proceeding to arthroscopic intervention.

Are there bilateral isokinetic shoulder rotator differences in basketball male players?

BACKGROUND

The internal (IR) and external (ER) rotator shoulder strength are often assess in the upper limb sports to prevent a risk of injuries. The purpose of this comparative study was to measure the agonist/antagonist balance of shoulder strength and to determine whether significant differences exist between the dominant and nondominant sides in basketball players compared to a control groups.

METHODS

During the championship, 23 elite male-basketball players (BB) and 23 healthy males (CG) were tested bilaterally on a Cybex Norm isokinetic dynamometer in a seated position with 45° shoulder abduction in the scapular plane at 60°.s-1 and 180°.s-1 in concentric (CON) and 60°.s-1 in eccentric (ECC) modes.

RESULTS

No significant differences were found for normalized values to body weight (N.m/kg-1) between the both groups and ER/IR, ECC/CON and functional deceleration ratios were similar. BB have a bilateral difference with higher ER of the dominant side comparatively to the opposite (P<0.05).

CONCLUSIONS

Unlike other sports that increase the performance of IR dominant side, the basketball player isokinetic profile could indicate a strengthening in the external rotators of the dominant side. This bilateral difference could be explained by the repetition of the specific movements in the ball control but this was not large enough for the ER/IR ratios to be significantly different with CG. The ratios analysis does not report an imbalance associated with a high risk of shoulder injuries.

Epidemiology of Shoulder and Elbow Injuries Among United States High School Baseball Players: School Years 2005-2006 Through 2014-2015

BACKGROUND

Shoulder and elbow injuries are common in young athletes, especially high school baseball players. Understanding the risk factors associated with baseball injuries is an essential first step in the development of injury prevention strategies.

PURPOSE

To provide a comprehensive understanding of the epidemiology of shoulder and elbow injuries among high school baseball players in the United States.

STUDY DESIGN

Descriptive epidemiological study.

METHODS

Baseball-related injury data were obtained from the National High School Sports-Related Injury Surveillance Study using High School RIO (Reporting Information Online), an Internet-based sports injury surveillance system. Athletic trainers from high schools across the country uploaded data regarding athlete-exposures (AEs) (defined as practice or game participation) and shoulder and elbow injuries from the school years 2005-2006 through 2014-2015.

RESULTS

A total of 241 shoulder injuries and 150 elbow injuries occurred during 1,734,198 AEs during the study period, for an overall shoulder injury rate of 1.39 per 10,000 AEs and an overall elbow injury rate of 0.86 per 10,000 AEs. The overall rates of injury were higher in competitions compared with practices for shoulders (rate ratio, 1.44; 95% CI, 1.11-1.85) and elbows (rate ratio, 2.15; 95% CI, 1.56-2.96). The majority of shoulder (39.6%) and elbow (56.9%) injuries were sustained by pitchers, and most injuries were chronic and caused by overuse. Position players were more likely to sustain injuries by contact with the playing surface or apparatus. For pitchers, muscle strains were the most common shoulder injuries (38.7%), while ligament sprains were the most common elbow injuries (42.7%). The majority of pitchers with shoulder (70.8%) and elbow (64.6%) injuries returned to play within 21 days. Among pitchers, a higher proportion of elbow injuries (11.4%) resulted in medical disqualification compared with shoulder injuries (5.6%). Among pitchers, the majority of shoulder (89.2%) and elbow (96.4%) injuries were managed nonsurgically.

CONCLUSION

Shoulder and elbow injury rates and patterns in high school baseball players differed between field positions (pitchers vs position players) and by type of exposure (practice vs competition). This study suggests several areas of emphasis for targeted injury prevention interventions, most notably limiting fatigue and preventing overuse injuries.

Electromyographic investigation of anterior and posterior regions of supraspinatus: a novel approach based on anatomical insights

Supraspinatus is composed of anterior and posterior regions that are distinct. To date, the relative electromyographic (EMG) activity of these regions during different tasks has not been investigated. This work, thus, evaluated activity of the anterior and posterior regions of supraspinatus during isometric actions in different postures. Data were analyzed from 11 healthy participants. Fine-wire electrodes were inserted into the anterior and posterior regions of supraspinatus. EMG activity was recorded during isometric abduction and external rotation exertions against 5% of body weight resistance. Three postures for abduction (30°, 60°, and 90° of humeral abduction, scapular plane) and two for external rotation (0° and 90° humeral abduction) were tested. Each participant’s data were normalized to the peak root mean square (RMS) values for the corresponding region. The RMS of the anterior region was divided by that of the posterior to calculate muscle activation ratios. Non-parametric statistics were used for analyses. The median ratio was lower during external rotation at 90° abduction compared to abduction at 30° (P = 0.003). These results suggest that the two regions of supraspinatus are functionally distinct during isometric tasks. The posterior region may play a more dominant role in postures with higher degrees of abduction and during external rotation exertions.

Influence of chronic neck pain on cervical joint position error (JPE): Comparison between young and elderly subjects

BACKGROUND

Evaluation of cervical joint position sense in subjects with chronic neck pain has gained importance in recent times. Different authors have established increased joint position error (JPE) in subjects with acute neck pain. However, there is a paucity of studies to establish the influence of chronic neck pain on cervical JPE.

OBJECTIVE

The objective of the study was to understand the influence of chronic neck pain on cervical JPE, and to examine the differences in cervical JPE between young and elderly subjects with chronic neck pain.

METHODS

Forty-two chronic neck pain patients (mean age 47.4) were compared for cervical JPE with 42 age-matched healthy subjects (mean age 47.8), using a digital inclinometer. The cervical JPE were measured in flexion, extension, and rotation in right and left movement directions.

RESULTS

The comparison of JPE showed significantly larger errors in subjects with chronic neck pain when compared to healthy subjects (p< 0.001). The errors were larger in all of the movement directions tested. Comparison between young and older subjects with chronic neck pain revealed no significant differences (P> 0.05) in cervical JPE.

CONCLUSIONS

Cervical joint position sense is impaired in subjects with chronic neck pain.

Acute effect and time course of extension and internal rotation stretching of the shoulder on infraspinatus muscle hardness

BACKGROUND

A decrease in flexibility of the infraspinatus muscle causes limitations in the range of shoulder motion. Static stretching (SS) is a useful method to improve muscle flexibility and joint mobility. Previous researchers investigated effective stretching methods for the infraspinatus. However, few researchers investigated the acute effect of SS on the infraspinatus muscle's flexibility. In addition, the minimum SS time required to increase the infraspinatus muscle's flexibility remains unclear. The aims of this study included investigating the acute effect of SS on the infraspinatus muscle's hardness (an index of muscle flexibility) by measuring shear elastic modulus and determining minimum SS time to decrease the infraspinatus muscle's hardness.

METHODS

This included measuring the effect of SS with extension and internal rotation of the shoulder on the infraspinatus muscle's hardness in 20 healthy men. Hence, shear elastic modulus of the infraspinatus was measured by ultrasonic shear wave elastography before and after every 10 seconds up to 120 seconds of SS.

RESULTS

Two-way analysis of variance indicated a significant main effect of SS duration on shear elastic modulus. The post hoc test indicated no significant difference between shear elastic modulus after 10 seconds of SS and that before SS. However, shear elastic modulus immediately after a period ranging from 20 seconds to 120 seconds of SS was significantly lower than that before SS.

CONCLUSION

The results suggested that shoulder extension and internal rotation SS effectively decreased the infraspinatus muscle's hardness. In addition, the results indicated that a period exceeding 20 seconds of SS decreased the infraspinatus muscle's hardness.

Pectoralis Minor Contracture in Throwing Shoulders of Asymptomatic Adolescent Baseball Players

BACKGROUND

Although scapular malpositioning is commonly associated with rotational deficits and risk of injury, modifiable causes of such malpositioning in overhead athletes are not well described.

PURPOSE/HYPOTHESIS

The purpose of this study was to examine the scapulothoracic profile of adolescent baseball players, specifically, pectoralis minor (PM) length. We hypothesized that PM would be shorter in throwing shoulders compared with nonthrowing shoulders.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Forty-nine healthy adolescent baseball players underwent clinical screening of PM lengths in throwing and nonthrowing shoulders by means of previously described, validated techniques. PM measurements were conducted while players were supine with arms at rest, sitting with arms at rest, and sitting with shoulders in maximal external rotation; measurements were made with a digital caliper and by assessment of table-to-acromion distance. Static scapular position and range of motion measurements were recorded. Demographic information and playing history were documented.

RESULTS

All players were male, they had a mean ± SD age of 16.2 ± 1.16 years, and they predominantly threw right-handed (83.7%). Sixty-nine percent of players were pitchers, 61.2% had played baseball for 9 or more months per year, and 67.3% had played in excess of 30 games in the previous year. Significant differences were noted during side-to-side comparisons within participants. Absolute PM length was significantly shorter in throwing compared with nonthrowing shoulders when measured with players sitting with arms at rest (by 3.7 ± 11.8 mm) and with their shoulders in maximal external rotation (by 4.8 ± 15.1 mm) (P < .004 for both). The PM index was significantly reduced in throwing compared with nonthrowing shoulders while players were supine with arms at rest (P = .007), sitting with arms at rest (P = .006), and sitting with shoulders in maximal external rotation (P < .001). Mean table-to-acromion distance was increased 7.7 ± 1.26 mm in throwing versus nonthrowing arms (P < .001). The scapular index was significantly reduced in throwing compared with nonthrowing shoulders (P < .005).

CONCLUSION

Asymptomatic adolescent baseball players have significant differences in PM length and static scapular measurements in throwing compared with nonthrowing shoulders. The clinical significance requires further investigation, but emphasis on PM stretching routines is encouraged.

Overuse Injuries of the Pediatric and Adolescent Throwing Athlete

In the hypercompetitive environment of year round youth baseball, arm pain is commonplace. Although much research has been done about injuries in the overhead throwing athlete, the emphasis has been on the more elite levels, where athletes have reached full development. The anatomy of the skeletally immature athlete, including open physeal plates and increased tissue laxity, raises unique issues in the presentation and treatment of repetitive throwing injuries of the elbow and shoulder. With a focus on "little leaguers," this discussion evaluates five of the most common elbow and shoulder injuries-Little Leaguer's elbow, ulnar collateral ligament sprain or tear, osteochondritis dissecans/Panner's disease, Little Leaguer's shoulder, and multidirectional instability. In the developmentally distinct pediatric athlete, pathogenesis, diagnosis, and treatment may differ from that established for adults. Offering early diagnosis and treatment appropriate to a child's level of development will enable youth to not only continue to play sports but to also maintain full functionality as active adults.

Top 50 cited journal articles on overhead throwing athletes: a bibliographic analysis

Background

The frequency of citations for a journal article is a reflection of its academic impact. The purpose of this study was to identify and characterize the top 50 cited journal articles related to overhead throwing athletes in the published literature.

Methods

The Web of Science database was searched on January 18, 2016, using the terms "throwing athlete," "baseball," and "pitcher" to identify the top 50 cited articles related to overhead throwing athletes using the all-database function. The type of study, country of origin, publishing journal, and year published were reviewed for each article.

Results

The top 50 articles identified were cited between 95 and 471 times and were published in 13 journals between 1969 and 2011. Most of the articles were small case series or nonsystematic literature reviews. The shoulder was the most common body region studied in the top 50 articles (33 of 50 [66%]). Among original studies (n = 43), there was a good representation of surgical management of shoulder and elbow pathology in overhead athletes (9 of 43 [20.9%]); however, most of the articles reported on shoulder and elbow kinematics (19 of 43 [44.2%]) and pathoanatomy (15 of 43 [34.9%]).

Conclusion

The greater prevalence of nonsurgical articles may reflect a continued effort to better understand the different pathologies specific to overhead throwing athletes. An understanding of the variable content and quality of frequently cited articles on overhead throwing athletes may serve as a stepping stone for future studies to advance the diagnosis and management of complex elbow and shoulder injuries in these high functional individuals.

Evaluation and management of shoulder pain in skeletally immature athletes

Shoulder pain in young athletes generally is a result of poor sports technique and overuse. A number intrinsic causes of shoulder pain have been identified. Pain may also be referred to shoulder area from cervical spine, neck and chest pathology. Overuse stress injury of the proximal humeral physis is important to recognize early in order to prevent later complications. Shoulder impingement syndrome is a general term used to describe multiple underlying lesions and relatively uncommon in young athletes. In adolescent athletes, glenohumeral instability is an important underlying pathomechanical basis for shoulder pain. Other less frequent causes reviewed here include atraumatic osteolysis of the distal clavicle, long thoracic and suprascapular neuropathies.

Exercise prescription for overhead athletes with shoulder pathology: a systematic review with best evidence synthesis

OBJECTIVE

To produce a best evidence synthesis of exercise prescription used when treating shoulder pathology in the overhead athlete.

DESIGN

A systematic review of exercises used in overhead athletes including case studies and clinical commentaries.

DATA SOURCES

MEDLINE, PubMed, SPORTDiscus and CINAHL from database inception through July 8, 2016.

METHODS

We examined data from randomised controlled trials and prospective cohort (level I-IV evidence) studies that addressed exercise intervention in the rehabilitation of the overhead athlete with shoulder pathology. Case studies and clinical commentaries (level V evidence) were examined to account for expert opinion-based research. Data were combined using best evidence synthesis and graded (A-F) recommendations (Centre for Evidence-Based Medicine).

RESULTS

There were 33 unique exercises in six level I-IV studies that met our inclusion criteria. Most exercises were single-plane, upper extremity exercises performed below 90^o of elevation. There were 102 unique exercises in 33 level V studies that met our inclusion criteria. These exercises emphasised plyometrics, kinetic chain and sport-specific training.

CONCLUSIONS AND RELEVANCE

Overall, evidence for exercise interventions in overhead athletes with shoulder pathology is dominated by expert opinion (grade D). There is great variability between exercise approaches suggested by experts and those investigated in research studies and the overall level of evidence is low. The strongest available evidence (level B) supports the use of single-plane, open chain upper extremity exercises performed below 90° of elevation and closed chain upper extremity exercises. Clinical expert pieces support a more advanced, global treatment approach consistent with the complex, multidimensional nature of sport.

Thrower's Fracture of the Humerus: An Investigation of Risk Factors Following an Unlikely Scenario: A Case Report

CASE

A 26-year-old amateur baseball player without prodromal arm pain sustained a thrower's fracture of the humerus on a warm-up throw performed with submaximal effort. The fracture occurred during the first throwing session following a 6-week layoff. The patient was treated nonoperatively and made a full recovery, but he elected to not return to throwing sports.

CONCLUSION

Because of the lack of risk factors in this case, we suggest that time off or irregularity in throwing may play a greater role in a thrower's fracture than previously established. Recreational throwers should undergo appropriate preseason training before returning to throwing.

What is the effect of a shoulder-strengthening program to prevent shoulder pain among junior female team handball players?

Background

Excessively high stresses are applied to the shoulder joint of handball players, mainly caused by overhead throwing. Shoulder pain is a significant problem among junior female team handball players and both male and female top-level team handball players in Norway.

Method

A randomized selection was performed among the best female junior teams (J 16) in the Trøndelag region of Norway in the 2014–2015 season. Three teams were randomized to the intervention group and three teams to the control group. Players in the intervention group (n=53) participated in a seven-month, three-times-a-week shoulder-muscle strength-training program, while those in the control group (n=53) participated in a comparable handball training, but did not conduct any specific strength training during the season.

Results

A strength-training program had no effect on the prevention of shoulder pain. Overall, the players reported shoulder pain, but graded the pain low on visual analog scale (VAS). Both the intervention group and the control group reported pain under 1 on VAS at baseline and posttest, and there was no significant difference within or between the groups when it came to the intensity of pain reported on VAS. A significant difference (p<0.048) was found between the groups on the sport-specific part of the quick-Disability of the Arm, Shoulder and Hand (DASH) form, but it did not fulfill the minimal demand to change and the players scored it low, something that indicates little functional problems when it comes to team handball. The intervention group was significantly stronger (p<0.008) on the push-ups test compared to the control group on the posttest. The intervention group increased the number of push-ups from 3.1 to 6.4, while the control group went from 2.3 to 3.6. Aside from this, there were no significant differences in between the groups.

Conclusion

A shoulder-strengthening program had no effect on the prevention of shoulder pain among junior female team handball players.

Use of the Spencer Technique on Collegiate Baseball Players: Effect on Physical Performance and Self-Report Measures

CONTEXT

Repeated overhead throwing in baseball players alters range of motion (ROM), contributing to shoulder injury. The Spencer technique has been used, anecdotally, to reduce the effects of throwing-induced limitations in ROM.

OBJECTIVE

To quantify the effects of a single administration of the Spencer technique on the ROM and performance of collegiate baseball pitchers.

METHODS

Pitchers from the Seton Hill University men's baseball team were randomly assigned to 2 treatment groups: Spencer technique or sham therapy. The first week consisted of baseline outcome measurements (1 week before treatment), including ROM (flexion, extension, abduction, adduction, internal rotation, and external rotation) of the dominant throwing arm, 10 maximum velocity throws, and self-reported performance using the Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow Score (KJOC-SES). The second week consisted of pretreatment ROM measurement, followed by a single treatment and repeated measurement of all outcomes.

RESULTS

Of 16 players, 15 met inclusion criteria. An effect of training on ROM between weeks 1 and 2 for all players consisted of significantly decreased internal rotation (P=.02) and increased external rotation (P=.04). A differential effect of treatment was found on the mean difference in internal rotation after treatment, compared with the mean difference before treatment on the same day (P=.01). Additionally, a trend toward statistical significance for abduction (P=.08) was noted. Analyses reveal that these effects were caused by significant increases in the internal rotation and abduction for the Spencer group only (P=.02). All other analyses of ROM, as well as performance measured by maximum velocity throws and the KJOC-SES, revealed no differential effect of treatment.

CONCLUSION

The results of this study support the use of the Spencer technique in counteracting the potentially negative effects of repeated throwing on internal rotation. However, a single administration did not affect functional ability in this study. Future studies of longer duration and including differing levels of play, injury status, and playing position will be needed to further evaluate the full potential of the Spencer technique in athletes who engage in repeated overhead arm movements.

Defining the Long-Toss: A Professional Baseball Epidemiological Study

Background:

Despite widespread use of long-toss throwing in baseball as a component of arm conditioning, interval throwing programs, and rehabilitation, long-toss distance and throwing mechanics remain controversial.

Purpose:

To ascertain the perceived definition of long-toss throwing through a survey of professional pitchers, pitching coaches (PCs), and certified athletic trainers (ATCs) associated with Major League Baseball.

Study Design:

Descriptive epidemiology study.

Methods:

Pitchers, PCs, and ATCs associated with 5 Major League Baseball organizations completed an anonymous survey that collected demographic data, personal use of long-toss throwing, and their perception of the distance and throwing mechanics that comprised long-toss.

Results:

A total of 321 surveys were completed by 271 pitchers, 19 PCs, and 31 ATCs. For all respondents, the mean distance considered as long-toss was 175 ft (95% CI, 170-181 ft). Respondents categorized the throwing mechanics of long-toss, with 36% reporting throwing “on a line” and 70% reporting long-toss as “not on a line.” Of those throwing “on a line,” 28% reported using crow-hop footwork while 60% used crow-hop footwork when throwing “not on a line.” Interpretation of long-toss distance significantly varied by position: pitchers, 177 ft (95% CI, 171-183 ft); PCs, 177 ft (95% CI, 155-200 ft); and ATCs, 157 ft (95% CI, 144-169 ft) (P = .048). When asked when long-toss throwing is used, pitchers reported using it more frequently in preseason (P = .007), during the season (P = .015), and in the off-season (P = .002) compared with that by ATCs. Functional goals for long-toss throwing demonstrated that pitchers and PCs use long-toss for shoulder stretching more frequently than ATCs (P < .001 and P = .026, respectively). ATCs used long-toss more than pitchers for interval throwing programs (P < .001).

Conclusion:

The definition varies for long-toss throwing distance and throwing mechanics. Pitchers and PCs believe that long-toss comprised longer distances than ATCs and employed long-toss differently for strength conditioning, training, stretching, and rehabilitation. This discrepancy highlights a potential lost opportunity for protecting the shoulder. While long-toss is an important tool, a more scientific definition is warranted to better elucidate its role in enhancing throwing performance and rehabilitation.

Effect of scapular stabilization during cross-body stretch on the hardness of infraspinatus, teres minor, and deltoid muscles: An ultrasonic shear wave elastography study

BACKGROUND

Posterior shoulder tightness is a contributing factor to shoulder injuries. Cross-body stretch is a method frequently prescribed to stretch the posterior shoulder structures. This stretching is performed horizontally adducting the shoulder with or without manual stabilization of the scapula by the therapist. However, no studies have investigated the effect of scapular stabilization during cross-body stretch using shear elastic modulus as an index of muscle hardness in vivo.

OBJECTIVES

The aim of this study was to quantitatively examine, using ultrasonic shear wave elastography, whether scapular stabilization during cross-body stretch effectively decreased the hardness of the infraspinatus, the teres minor, or the posterior portion of the deltoid muscles.

DESIGN

A randomized, repeated-measures, cross-over design.

METHOD

Twenty healthy men participated in this study. The shear elastic modulus of the teres minor, the superior and inferior portions of the infraspinatus, and the posterior portion of the deltoid were measured before, and immediately after cross-body stretch with and without scapular stabilization.

RESULTS

The shear elastic modulus of the superior and inferior portions of the infraspinatus decreased significantly after cross-body stretch with scapular stabilization, but there was no significant change in the shear modulus of the measured muscles after cross-body stretch without scapular stabilization.

CONCLUSIONS

Our results suggest that manual scapular stabilization during cross-body stretch effectively decreases the hardness of the infraspinatus muscle.