Current concepts in the rehabilitation of the overhead throwing athlete

Correlation of shoulder and elbow injuries with muscle tightness, core stability, and balance by longitudinal measurements in junior high school baseball players

[Purpose] The present study longitudinally investigated injury occurrences and the risk factors for muscle tightness, core stability, and dynamic standing balance among junior high school student baseball players. [Subjects] Thirty-nine male students, belonging to baseball clubs at 2 junior high schools, participated in this study. [Methods] Study measurements were obtained twice, once in the early stage of the baseball season (March) and once at the end of the season (July). All subjects underwent muscle tightness testing, the Star Excursion Balance Test (SEBT), and trunk endurance testing during each measurement session. [Results] Fifteen players experienced episodes of elbow or shoulder pain while throwing. Players in the pain group demonstrated a significant increase in the tightness of their shoulder internal rotators, axis-leg quadriceps, and axis-leg hamstrings. There was no clear evidence of differences of changes in core stability and dynamic standing balance between the groups. [Conclusion] The results of this study suggest that lower extremity muscle tightness early in a season and the subsequent decline in the flexibility of the axis-leg quadriceps and hamstrings during the season may be due to an increased upper extremity load while throwing, thus producing shoulder and elbow pain.

Nonoperative and postoperative rehabilitation for glenohumeral instability

The glenohumeral joint is an inherently unstable joint that relies on the interaction of the dynamic and static stabilizers to maintain stability. Disruption of this interplay or poor development of any of these factors may result in instability, pain, and a loss of function. Rehabilitation will vary based on the type of instability present and the key principles described. Whether a course of nonoperative rehabilitation is followed or the patient presents postoperatively, a comprehensive program designed to establish full ROM and balance capsular mobility, in addition to maximizing muscular strength, endurance, proprioception, dynamic stability, and neuromuscular control is essential. A functional approach to rehabilitation using movement patterns and sport-specific positions along with an interval sport program will allow a gradual return to athletics. The focus of the program should minimize the risk of recurrence and ensure that the patient can safely return to functional activities.

Biomechanical comparison of the interval throwing program and baseball pitching: upper extremity loads in training and rehabilitation

BACKGROUND

The interval throwing progression has been part of baseball rehabilitation and conditioning for decades, yet little is known about the upper extremity loads an athlete is subjected to during this progression.

HYPOTHESIS

A biomechanical comparison of fastball pitching, variable-effort pitching, and throwing various flat-ground distances will show significant torque differences in the throwing shoulder and elbow.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twenty-nine healthy college baseball pitchers were analyzed using a quantitative motion analysis system. The participants threw from flat ground at distances of 18, 27, 37, and 55 m, having been instructed to throw "hard, on a horizontal line." The participants then threw fastballs 18.4 m from a mound at 3 different effort levels: 60%, 80%, and full effort. The kinetic values for humeral internal rotational torque (HIRT) and elbow valgus load (EVL) were extracted for each throw. Repeated-measures analyses of variance (ANOVAs) were used to compare all 7 throwing conditions within pitchers. The kinetic data were also compared against ball velocity to evaluate throwing efficiency. A separate analysis was conducted using a 3-level repeated-measures ANOVA with post hoc paired t tests comparing just the variable-effort throws from the mound.

RESULTS

No statistically significant differences were found in either HIRT or EVL between any of the flat-ground distances and throwing from the mound (P > .05). Despite similar biomechanical loads compared with the mound, throwing from flat ground showed significantly decreased ball velocity (82% of maximum). Statistically significant differences were found in humeral internal rotational torque and elbow valgus load between fastball pitching off the mound at 60% and 100%, as these parameters increased with throwing effort (P < .05). At 60% perceived effort from the mound, pitchers generated forces of 76% and ball speeds approaching 84% of maximum.

CONCLUSION

Partial-effort pitching demonstrates significantly lower loads on the shoulder and elbow. Flat-ground throwing at even the shortest distances had similar biomechanical loads compared with pitching from the mound, yet at significantly lower ball velocity. This illustrates the mechanical advantage and increased efficiency of throwing from a mound. No increase in shoulder or elbow loads was seen with increasing distances from flat ground, as pitchers began using a "crow hop" for the longer distances, facilitating the throw with their lower extremity. The mechanical advantage of throwing from a mound or using the crow hop is likely protective during rehabilitation and training throws.

CLINICAL RELEVANCE

The findings of this study may be used to improve rehabilitation programs designed for baseball players returning from shoulder or elbow injury.

Muscle activity pattern of the shoulder external rotators differs in adduction and abduction: an analysis using positron emission tomography

BACKGROUND

The muscle activity pattern during shoulder external rotation has not been fully clarified. This study aimed to determine the activities involved in external rotation in the adducted and abducted positions using positron emission tomography (PET).

METHODS

Seven healthy volunteers underwent PET examinations after performing external rotation using an elastic band at both 0° and 90° of shoulder abduction in the frontal plane. External rotation exercise was performed before and after injection of fluorine 18 fluorodeoxyglucose, which was followed by PET examination. The protocols for external rotation exercise were identical between the 2 shoulder positions. To obtain control data, PET examination was also performed under resting conditions. The order of these 3 PET examinations was randomized, and they were performed at intervals of 1 week or greater. Each PET image was fused to the corresponding magnetic resonance image to identify each shoulder muscle. After this, the standardized uptake value was calculated in each muscle and was compared between the 2 shoulder positions.

RESULTS

The infraspinatus showed the greatest muscle activity during external rotation at 0° of abduction, whereas the teres minor showed the greatest activity at 90° of abduction. The teres minor-infraspinatus ratio at 90° of abduction (mean ± SD, 1.21 ± 0.23) was significantly higher than that at 0° of abduction (0.84 ± 0.15) (P < .01).

CONCLUSION

The infraspinatus and teres minor are the main shoulder external rotators. The teres minor is more important as an external rotator in abduction than in adduction.

Increase in humeral retrotorsion accounts for age-related increase in glenohumeral internal rotation deficit in youth and adolescent baseball players

BACKGROUND

Glenohumeral internal rotation deficit (GIRD) is the difference in internal rotation range of motion (IRROM) between the dominant and nondominant limbs. Pathological GIRD of greater than 15° to 25° has previously been linked to shoulder and elbow injuries in baseball players. Because of its relationship to shoulder and elbow disorders, research has focused on understanding the underlying factors that contribute to changes in IRROM and ultimately GIRD. The rotation deficit reportedly increases during adolescence, but it remains unclear whether this change is caused by changes in osseous properties or soft tissue tightness.

PURPOSE

To evaluate the influence of age group on GIRD, humeral retrotorsion, retrotorsion-adjusted GIRD, and total range of motion (TROM) in healthy baseball players.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Four groups of healthy baseball players participated in the study: 52 youth (aged 6-10 years), 52 junior high school (JH) (aged 11-13 years), 70 junior varsity (JV) (aged 14-15 years), and 113 varsity (aged 16-18 years) players. Internal rotation range of motion, external rotation range of motion (ERROM), and humeral retrotorsion were measured bilaterally using a digital inclinometer and diagnostic ultrasound. Retrotorsion-adjusted IRROM was calculated as the available IRROM from the humeral retrotorsion position; TROM was calculated as the sum of IRROM and ERROM; and GIRD, the difference in humeral retrotorsion between limbs, adjusted GIRD, and the difference in TROM between limbs were calculated as the difference between the dominant and nondominant sides. Four separate analyses of variance were used to compare these variables between age groups.

RESULTS

There was a significant group difference in GIRD (F3,284 = 8.957; P < .001) and a difference in humeral retrotorsion between limbs (F3,284 = 9.688; P < .001). Also, GIRD was greater in varsity participants compared with youth (mean difference [MD], 5.05°) and JH (MD, 4.95°) participants and in JV participants compared with JH (MD, 5.36°) and youth (MD, 5.47°) participants. The difference in humeral retrotorsion between limbs was greater in varsity participants compared with youth (MD, 8.79°) and JH (MD, 5.52°) participants and in JV participants compared with youth participants (MD, 7.88°). There were no significant differences in adjusted GIRD (F3,284 = 1.136; P = .335) or TROM (F3,284 = 1.214; P = .305).

CONCLUSION

Glenohumeral internal rotation deficit and humeral retrotorsion increased with age in youth/adolescent baseball players, while retrotorsion-adjusted GIRD and TROM remained unchanged. An age-related increase in GIRD is primarily attributed to humeral retrotorsion rather than soft tissue tightness.

CLINICAL RELEVANCE

While there was an increase in GIRD from youth league to high school participants, TROM and retrotorsion-adjusted GIRD remained constant across the age groups, indicating that this increase between the age groups is not pathological GIRD and may not contribute to an increased injury risk.

[The throwing shoulder]

BACKGROUND

During the throwing motion high forces are placed on the athlete's shoulder and extreme positions of external rotation and abduction are reached. The dynamic and static stabilizers of the glenohumeral joint need to handle a delicate balance between shoulder mobility and stability.

CAUSES OF INJURY

Repetitive forces lead to adaptive osseous, capsular, ligament and muscular changes. This should increase external rotation of the shoulder and thus initially help to improve performance but ultimately could cause shoulder pathologies. For instance, tissue overuse can result in muscular imbalance, functional instability and posterior capsular contracture with the development of a glenohumeral internal rotation deficit.

INJURY PATTERNS

An internal impingement is often observed in throwing athletes which can be subdivided into the more common posterosuperior type and the rarer anterosuperior type. Typical lesions in the throwing shoulder are articular-sided partial rotator cuff tears, labrum and biceps tendon lesions and edema, cysts or osteochondral lesions of the humeral head or glenoid.

DIAGNOSTICS

For an accurate diagnosis it is important to include the history, a thorough physical examination and magnetic resonance arthrography. The correlation of clinical examination and imaging is critical to identify symptomatic lesions.

THERAPY

If conservative therapy fails or in cases of significant structural damage resulting in clinical symptoms, surgical treatment should be considered based on the underlying pathology and carried out using established techniques and criteria.

Changes in collegiate starting pitchers' range of motion after single game and season

The relationship of changes in glenohumeral range of motion (ROM) in a pitcher's throwing shoulder to a single pitching episode is not well described, and the causes of such changes over a season are controversial. We hypothesized that in pitchers for a collegiate baseball team, external rotation (ER) would increase, internal rotation (IR) would decrease, total ROM would be maintained, and the glenohumeral IR deficit would worsen in starting pitchers' shoulders after single pitching episodes and after the season. Participants were 6 starting pitchers for all 25 home games from a Division III National Collegiate Athletic Association team during 1 regular spring season. One examiner measured glenohumeral ER, IR, and total ROM with the arm abducted 90° pregame before stretching or throwing and immediately postgame before shoulder icing. Bilateral measurements were obtained on supine pitchers via a long-arm goniometer and custom bubble inclinometer. Innings, pitch count, and types of pitches were recorded for possible associations with any glenohumeral motion changes. Paired t tests were used to compare dominant and nondominant glenohumeral differences in ROM (significance, P < 0.05). Compared with pregame values, single-start postgame glenohumeral ER significantly increased (7.9° ± 2.2°), single-start IR did not significantly change, and single-start total ROM significantly increased (7.4° ± 3.4°). Compared with preseason values, postseason glenohumeral ER significantly increased (10.2° ± 6.2°), IR significantly decreased (-17.8° ± 6.7°), and total ROM significantly decreased (-7.7° ± 5.2°). In the collegiate throwing shoulder, changes in ER and total ROM occurred after 1 episode of starting pitching, and changes in ER, IR, and total ROM occurred over the full season. There was no association between the ROM changes and innings pitched, pitch count, or types of pitches thrown. In conclusion, for collegiate pitchers, changes in glenohumeral ROM occur after single starts and over the season, suggesting that monitoring motion changes throughout the season may be beneficial.

The modified sleeper stretch and modified cross-body stretch to increase shoulder internal rotation range of motion in the overhead throwing athlete

SYNOPSIS

Stretching techniques that focus on increasing posterior shoulder soft tissue flexibility are commonly incorporated into prevention and treatment programs for the overhead athlete. The cross-body and sleeper stretch exercises have been described as stretching techniques to improve posterior shoulder soft tissue flexibility and to increase glenohumeral joint internal rotation and horizontal adduction range of motion in the overhead athlete. But, based on the inability to stabilize the scapula and control glenohumeral joint rotation with the cross-body stretch and the potential for subacromial impingement with the sleeper stretch, the authors recommend modifications to both of these commonly performed stretches. This clinical commentary reviews the literature on posterior shoulder stretches, describes modifications to both of these commonly performed stretches, and outlines a strategy to maintain or improve posterior shoulder soft tissue flexibility and glenohumeral joint internal rotation range of motion in the overhead athlete.

LEVEL OF EVIDENCE

Therapy, level 5.

Baseball players diagnosed with ulnar collateral ligament tears demonstrate decreased balance compared to healthy controls

STUDY DESIGN

Cross-sectional.

OBJECTIVES

To compare lower extremity balance and shoulder range of motion in baseball players with ulnar collateral ligament (UCL) tears to a healthy cohort. Background Throwing is a complex motion that requires balance and coordination to effectively transfer energy through the kinetic chain. In theory, poorer balance could negatively affect throwing mechanics and lead to injury.

METHODS

Thirty baseball players (mean ± SD age, 18.5 ± 1.9 years) with a diagnosis of a UCL tear of their throwing arm were compared to 30 players (age, 19.0 ± 1.1 years) without a UCL tear. All participants were competing at either the high school or collegiate level and reported an average ± SD of 13.5 ± 1.7 years of playing experience. The Y Balance Test composite scores were calculated for the stance and lead lower extremities of all players. Shoulder range of motion was used to calculate glenohumeral internal rotation deficit and side-to-side differences in total rotational motion. Group comparisons were made between participants with and without UCL tears using independent t tests.

RESULTS

Baseball players with UCL tears scored significantly lower on the Y Balance Test for both the stance (P<.001) and lead (P<.001) lower extremities compared to the noninjured cohort. No between-group differences were noted in glenohumeral internal rotation deficit (P = .453), whereas the mean ± SD side-to-side difference in total rotational motion was -6.0° ± 9.6° for the injured group, compared to -0.4° ± 9.6° for the control group (P = .028).

CONCLUSION

Participants with a UCL tear demonstrated decreased performance for their stance and lead lower extremities during the Y Balance Test. These data are consistent with a clinical hypothesis of a potential association between impaired balance and UCL tears in high school and collegiate baseball players. The lower total rotational motion of the dominant shoulder in participants with UCL tears needs to be considered in the interpretation of those results.

Profiling the isokinetic shoulder rotator muscle strength in 13- to 36-year-old male and female handball players

OBJECTIVES

To evaluate the external (ER) and internal rotator (IR) muscles' isokinetic peak torque and conventional and functional strength ratios in handball players and controls of different ages.

DESIGN

Cross-sectional and descriptive analysis.

SETTING

Exercise Physiology Laboratory.

PARTICIPANTS

A total of 228 participants (108 athletes and 120 controls) were divided into five groups according to age, ranging from 13 to 36 years old.

MAIN OUTCOME MEASURES

Isokinetic tests were performed concentrically at 60 and 300 deg s(-1) and eccentrically at 300 deg s(-1).

RESULTS

The differences between the athletes and controls regarding the peak torque of the ER and IR muscles were significant in males older than 18 years. The peak torque of the IR and ER muscles increased significantly across age in male athletes, but not in female athletes, except in the case of ER peak torque, which differed significantly between 13 and 16 years old. The female athletes presented higher conventional ratios (0.81 ± 0.07) than males (0.66 ± 0.08). Values represent means and standard deviations. Athletes and controls showed mean functional strength ratios below 1.0.

CONCLUSIONS

Although there were no muscular ratio differences between the athletes and the controls, their ratio values were below the literature-recommended reference values to prevent shoulder injuries.

Glenohumeral range of motion in handball players with and without throwing-related shoulder pain

BACKGROUND

Overhead athletes are subject to adaptations in the shoulder including glenohumeral internal rotation deficit (GIRD). It has been documented that this alteration is more evident in overhead athletes with pain. Our objective was to compare glenohumeral rotation motion between symptomatic and asymptomatic handball players.

MATERIALS AND METHODS

Glenohumeral rotation range of motion, GIRD, external rotation gain (ERG), and total rotation motion were determined with a standard goniometer in 30 handball players with pain and 27 without pain. Differences between the throwing and non-throwing shoulder were determined in each group.

RESULTS

Handball players with pain had significantly greater GIRD (P = .002), ERG (P = .027), and external rotation in the throwing arm (P = .042) and lesser internal rotation in the throwing arm (P = .029) in comparison to the athletes without pain. Comparisons between limbs exhibited a significant difference in the 2 groups regarding internal and external rotation (P < .02), but differences within the group with pain were greater. Differences were not found in the total rotation motion between the 2 groups.

CONCLUSION

Handball players showed specific adaptations in the throwing shoulder; in particular, handball players with pain have greater GIRD, ERG, and external rotation and lesser internal rotation of the throwing shoulder.

Shoulder adaptations among pitchers and position players over the course of a competitive baseball season

OBJECTIVE

To determine if throwing arm shoulder range of motion (ROM) and scapular kinematic differences exist between baseball pitchers and position players over the course of a baseball season.

DESIGN

Prospective cohort.

SETTING

Professional baseball athletic training room.

PARTICIPANTS

Sixteen asymptomatic professional baseball pitchers and 16 position players.

INDEPENDENT VARIABLES

Preseason glenohumeral (GH) posterior tightness and scapular position.

MAIN OUTCOME MEASURES

Throwing arm GH horizontal adduction ROM and GH internal rotation bilateral asymmetry ROM, as well as bilateral differences in forward scapular posture and throwing arm scapular upward rotation at rest, 60, 90, and 120 degrees of humeral elevation were measured. These measurements were taken before and at the conclusion of a 140-game baseball season.

RESULTS

Analyses of covariances showed no significant differences in GH horizontal adduction or internal rotation asymmetry ROM between groups over the course of the season. However, the pitchers developed significantly less scapular upward rotation at 60 degrees (P = 0.007) and 90 degrees (P = 0.006) of humeral elevation compared with the position players during the season. Forward scapular posture (P = 0.23) and scapular upward rotation at 0 degrees (P = 0.93) and 120 degrees (P = 0.29) of humeral elevation were not significantly different between groups.

CONCLUSIONS

These results suggest that baseball position players develop more scapular upward rotation over the course of a competitive season than pitchers. This discrepancy may increase the pitchers' risk of injury and may partially explain their higher incidence of shoulder injury compared with position players. Therefore, pitchers may benefit from strengthening exercises and stretches aimed at increasing scapular upward rotation throughout the competitive baseball season.

Surgical repair and rehabilitation of a combined 330° capsulolabral lesion and partial-thickness rotator cuff tear in a professional quarterback: a case report

STUDY DESIGN

Case report.

BACKGROUND

Traumatic glenohumeral dislocations with concomitant rotator cuff and capsular injuries present a unique and challenging surgical and rehabilitative condition, particularly in the overhead-throwing athlete. Multiple injuries of the shoulder complex create the potential for complications in the course of recovery and place a full return to high-level sport at risk. The purpose of this case report is to present the multiphased rehabilitation approach of an elite professional quarterback after an acute 330° capsulolabral reconstruction and rotator cuff repair as a result of a luxatio erecta injury.

CASE DESCRIPTION

A 26-year-old male professional football player, a quarterback, sustained a right luxatio erecta shoulder dislocation while trying to recover a fumble during a regular-season game. The injury occurred when he was hit in the back of his throwing shoulder, which was in an abducted and externally rotated position, while lying on the ground. Five days postinjury, he underwent a 330° capsulolabral repair, with concomitant rotator cuff repair and subacromial decompression. He completed 28 weeks of a multiphased rehabilitation program.

OUTCOMES

The patient returned to play in the National Football League (NFL) 8 months later, for the start of the next season, during which he had his most productive year as a professional quarterback, leading the league in passing yards and finishing third in the league for the number of touchdowns. Since the injury, the patient has played 6 consecutive seasons, starting over 96 consecutive, regular-season games and maintaining a very high level of play.

DISCUSSION

This case report highlights the clinical decision-making process and management of this rare, severe injury.

Selective activation of the infraspinatus muscle

CONTEXT

To improve selective infraspinatus muscle strength and endurance, researchers have recommended selective shoulder external-rotation exercise during rehabilitation or athletic conditioning programs. Although selective strengthening of the infraspinatus muscle is recommended for therapy and training, limited information is available to help clinicians design a selective strengthening program.

OBJECTIVE

To determine the most effective of 4 shoulder external-rotation exercises for selectively stimulating infraspinatus muscle activity while minimizing the use of the middle trapezius and posterior deltoid muscles.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 30 healthy participants (24 men, 6 women; age = 22.6 ± 1.7 years, height = 176.2 ± 4.5 cm, mass = 65.6 ± 7.4 kg) from a university population.

INTERVENTION(S)

The participants were instructed to perform 4 exercises: (1) prone horizontal abduction with external rotation (PER), (2) side-lying wiper exercise (SWE), (3) side-lying external rotation (SER), and (4) standing external-rotation exercise (STER).

MAIN OUTCOME MEASURE(S)

Surface electromyography signals were recorded from the infraspinatus, middle trapezius, and posterior deltoid muscles. Differences among the exercise positions were tested using a 1-way repeated-measures analysis of variance with Bonferroni adjustment.

RESULTS

The infraspinatus muscle activity was greater in the SWE (55.98% ± 18.79%) than in the PER (46.14% ± 15.65%), SER (43.38% ± 22.26%), and STER (26.11% ± 15.00%) (F3,87 = 19.97, P < .001). Furthermore, the SWE elicited the least amount of activity in the middle trapezius muscle (F3,87 = 20.15, P < .001). Posterior deltoid muscle activity was similar in the SWE and SER but less than that measured in the PER and STER (F3,87 = 25.10, P < .001).

CONCLUSIONS

The SWE was superior to the PER, SER, and STER in maximizing infraspinatus activity with the least amount of middle trapezius and posterior deltoid activity. These findings may help clinicians design effective exercise programs.

Glenohumeral rotational motion and strength and baseball pitching biomechanics

CONTEXT

Addressing loss of shoulder range of motion and rotator cuff weakness in injury-prevention programs might be an effective strategy for preventing throwing arm injuries in baseball pitchers. However, the influence of these clinical measures on pitching biomechanics is unclear.

OBJECTIVE

To evaluate the relationships among clinical measures of shoulder rotational motion and strength and 3-dimensional pitching biomechanics and to evaluate the presence of coupling between the shoulder and the elbow during pitching to provide insight into the influence of clinical shoulder characteristics on elbow biomechanics.

DESIGN

Cross-sectional study.

SETTING

Biomechanics laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 27 uninjured male high school baseball pitchers (age = 16 ± 1.1 years, height = 183 ± 7 cm, mass = 83 ± 12 kg).

MAIN OUTCOME MEASURE(S)

Clinical measures included shoulder internal- and external-rotation range of motion and peak isometric internal- and external-rotator strength. Three-dimensional upper extremity biomechanics were assessed as participants threw from an indoor pitching mound to a target at regulation distance. Linear regressions were used to assess the influence of clinical measures on the peak shoulder internal and external rotation moments and the peak elbow-adduction moment.

RESULTS

We found a positive relationship between clinically measured internal-rotator strength and shoulder external-rotation moment (R(2) = 0.181, P = .04) during pitching. We also noted an inverse relationship between clinically measured external-rotation motion and the elbow-adduction moment (R(2) = 0.160, P = .04) and shoulder internal-rotation moment (R(2) = 0.250, P = .008) during pitching. We found a positive relationship between peak shoulder internal-rotation moment and the peak elbow-adduction moment (R(2) = 0.815, P < .001) during pitching.

CONCLUSIONS

This study provides insight into the effects of shoulder strength and motion on pitching biomechanics and how these clinical measures might contribute to throwing arm injuries in the baseball pitcher. A relationship also was identified between peak shoulder and elbow moments in the throwing arm during pitching, providing biomechanical support for addressing clinical shoulder characteristics as a potential strategy for preventing elbow injury.

Diagnosis and management of superior labral anterior posterior tears in throwing athletes

Injury to the superior glenoid labrum is increasingly recognized as a significant source of shoulder pain and dysfunction in the throwing athlete. Several theories have been proposed to explain the pathogenesis of superior labral anterior posterior (SLAP) tears. The clinical examination of the superior labrum-biceps tendon complex remains challenging because of a high association of other shoulder injuries in overhead athletes. Many physical examination findings have high sensitivity and low specificity. Advances in soft tissue imaging such as magnetic resonance arthrography allow for improved detection of labrum and biceps tendon lesions, although correlation with history and physical examination is critical to identify symptomatic lesions. Proper treatment of throwers with SLAP tears requires a thorough understanding of the altered biomechanics and the indications for nonoperative management and arthroscopic treatment of these lesions.

The disabled throwing shoulder: spectrum of pathology-10-year update

In the 10 years since the current concept series entitled "The Disabled Throwing Shoulder: Spectrum of Pathology" was conceived and written, many studies have been reported that add much more information to the understanding of the disabled throwing shoulder (DTS). The editors of Arthroscopy and the authors of the original series believed that an update to the original series would be beneficial to provide an organized overview of current knowledge that could update the thought process regarding this problem, provide better assessment and treatment guidelines, and guide further research. A dedicated meeting, including current published researchers and experienced clinicians in this subject, was organized by the Shoulder Center of Kentucky. The meeting was organized around 5 areas of the DTS that were highlighted in the original series and appear to be key in creating the DTS spectrum and to understanding and treating the DTS: (1) the role of the kinetic chain; (2) the role and clinical evaluation of the scapula; (3) the role of deficits in glenohumeral rotation, glenohumeral internal rotation deficit, and total range-of-motion deficit in the causation of labral injury and DTS; (4) the role of superior labral (SLAP) injuries and rotator cuff injuries; and (5) the composition and progression of rehabilitation protocols for functional restoration of the DTS. The meeting consisted of presentations within each area, followed by discussions, and resulted in summaries regarding what is known in each area, what is not known but thought to be important, and strategies to implement and enlarge the knowledge base.

Shoulder range of motion deficits in baseball players with an ulnar collateral ligament tear

BACKGROUND

Shoulder range of motion (ROM) deficits are associated with elbow injury in baseball players.

PURPOSE

To compare the ROM characteristics of baseball players with a diagnosed ulnar collateral ligament (UCL) tear with those of a group of age-, activity-, and position-matched healthy controls.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Sixty male competitive high school and collegiate baseball players participated. Thirty athletes (age [mean ± standard deviation], 18.20 ± 1.56 years) with a diagnosed UCL tear were compared with 30 (age, 18.57 ± 0.86 years) age-, activity-, and position-matched players without a UCL injury. Of the 60 participants, there were 44 pitchers, 4 catchers, 5 infielders, and 7 outfielders. Participants were measured for shoulder internal rotation (IR), external rotation (ER), and horizontal adduction (HA) at 90° of shoulder elevation. Participants were also measured for elbow extension in a seated position. Group comparisons were made between participants with and without a UCL injury using independent t tests with an α level set at P < .05. All measurements were taken bilaterally, and the differences (involved to uninvolved) were used to calculate means for all variables, including glenohumeral internal rotation deficit (GIRD), total rotational motion (TRM), HA, and elbow extension.

RESULTS

Baseball players with a UCL tear (UCLInj) exhibited significantly greater deficits in TRM compared with the control group of healthy baseball players (NUCLInj) (UCLInj = -6.67° ± 11.82°, NUCLInj = 0.93° ± 9.91°; P = .009). No group differences were present for GIRD (UCLInj = -12.53° ± 5.98°, NUCLInj = -13.63° ± 5.90°; P = .476), HA (UCLInj = -3.00° ± 5.01°, NUCLInj = -3.23° ± 5.15°; P = .860), or elbow extension (UCLInj = -2.63° ± 7.86°, NUCLInj = -1.17° ± 2.76°; P = .339). Pitchers with a UCL tear had significantly greater deficits in TRM (UCLInjPitch = -6.96° ± 11.20°, NUCLInjPitch = 1.29° ± 8.33°; P = .0087) and dominant shoulder ER (UCLInjPitch = 112.04° ± 14.35°, NUCLInjPitch = 121.85° ± 9.46°; P = .011) than pitchers without a UCL tear.

CONCLUSION

A deficit in TRM is associated with a UCL tear in baseball players. Although GIRD may be prevalent in throwers, it may not be associated with a UCL injury. When examining ROM in baseball players, it is important to assess both TRM and GIRD.

A Comparative Study on Shoulder Rotational Strength, Range of Motion and Proprioception between the Throwing Athletes and Non-athletic Persons

Purpose

The repetitive micro traumatic stresses placed on the athletes shoulder joint complex during the throwing motion challenge the surrounding tissues. The purpose of this study was to compare shoulder rotational strength, range of motion and proprioception between the throwing athletes and non-athletic persons.

Methods

Fifteen throwing athletes and 15 non-athletes participated in a nonrandom case – control study. Strength of shoulder rotational movements was tested with a hand held dynamometer. The ranges of internal and external rotation of shoulder were measured by a standard goniometer. The ability of subjects to replicate the target position and kinesthetic sense was examined on the subjects’ right shoulder by using a continuous passive motion device. Independent and paired t tests were used to statistically analyze between and within group differences.

Results

No significant difference was detected on the range of internal rotation between throwing athletes and non-athletic candidates (P=0.3). The range of external rotation was significantly more in athletic subjects (P=0.03). The results also showed that throwing athletes demonstrated a significantly higher isometric strength of shoulder external and internal rotation than the non-athletic group (P<0.05). However, the comparison of the internal and external rotation strength of dominant side in each group showed that throwing athletes showed a significant lower isometric strength of shoulder external rotation than internal rotation (P<0.001). It was also demonstrated higher joint position acuity in the throwing athletes than non athlete subjects (P=0.01).

Conclusion

The repetitive nature of overhead throwing and the high forces that it causes result in adaptive changes of the dominant extremity. Throwing can lead to mobility, strength and neural adaptation.

Glenohumeral range of motion in major league pitchers: changes over the playing season

Background:

Although overhead throwing athletes may develop unique glenohumeral range of motion characteristics, to our knowledge these characteristics have not been studied longitudinally in major league pitchers.

Hypothesis:

Major league pitchers (starters and relievers) experience an increase in glenohumeral external rotation and a decrease in internal rotation and total range of motion. Glenohumeral internal rotation deficit worsens over a regular playing season.

Study Design:

Retrospective cohort study.

Methods:

In 21 major league baseball pitchers (29 individual playing seasons), glenohumeral range of motion was measured in external and internal rotation for the throwing and nonthrowing shoulders before and at the conclusion of the regular season. The total range of motion (the sum of external rotation and internal rotation) and the glenohumeral internal rotation deficit were calculated (the difference between internal rotation of the nonthrowing shoulder minus that of the throwing shoulder), and data were compared between starting and relief pitchers.

Results:

The overall mean changes in external rotation (+1.5°), internal rotation (+2.7°), and total range of motion (+3.3°) were not statistically significant. However, starting pitchers showed statistically significant increases in internal rotation (+6.5°, P = 0.01) and total range of motion (+7.9°, P = 0.04), whereas relief pitchers had significant worsening of glenohumeral internal rotation deficit (+5.3°, P = 0.04).

Conclusions:

The characteristics of glenohumeral range of motion in major league pitchers did not differ significantly from the beginning to the end of a season, but significant changes did occur between starting and relief pitchers.

Clinical Relevance:

Adaptations to the daily routines of starter and reliever pitchers may be warranted on the basis of these findings.

Data-based interval throwing programs for baseball players

Context:

Baseball throwing injuries are common. Emphasis on injury prevention and rehabilitation is made in an attempt to keep athletes on the field of competition. Interval throwing programs are an integral part of training, conditioning, and returning an injured baseball player to the game.

Evidence Acquisition:

Development of data-driven programs was based on the number, type, distance, and intensity of throws during games, across the spectrum of ages and positions for baseball athletes at all levels of play. Statistical analysis by age, position, and level of play determined the need for separate throwing programs. Means, the high range, game rules, and practical considerations were used to develop each data-based interval throwing program.

Results:

Data-based age and level-of-play interval throwing programs for pitchers, catchers, infielders, and outfielders have been developed, tested, and implemented for more than 10 years. Progression is based on type and location of injury, symptoms in response to throwing, and preinjury performance profile. Although the throwing programs are highly structured, there is ample opportunity to modify them to meet the needs of individual athletes.

Conclusion:

Data-based interval throwing programs for baseball athletes are an integral training and conditioning element for both injured and uninjured athletes who are preparing for sports participation. Medical team members should equip themselves with an understanding of how to use the programs for safe training, conditioning, and return to play.

Current concepts in the evaluation and treatment of the shoulder in overhead-throwing athletes, part 1: physical characteristics and clinical examination

The overhead-throwing athlete is a challenging sports medicine patient. The repetitive microtraumatic stresses imposed on the athlete's shoulder joint complex during the throwing motion constantly places the athlete at risk for injury. These stresses may effect several adaptations to normal shoulder range of motion, strength, and scapula position. The clinician should therefore appreciate the unique physical characteristics of the overhead-throwing athlete to accurately evaluate and treat throwing-related injuries.

A randomized controlled single-blinded comparison of stretching versus stretching and joint mobilization for posterior shoulder tightness measured by internal rotation motion loss

BACKGROUND

Posterior shoulder tightness, as demonstrated by limited internal rotation range of motion, is a suggested factor in many shoulder pathologies. Methods to increase posterior shoulder mobility may be beneficial.

HYPOTHESIS

Shoulder internal rotation range of motion will not change with either of 2 interventions: cross-body stretch alone and cross-body stretch plus posterior capsule joint mobilization.

STUDY DESIGN

Randomized controlled single-blinded clinical trial.

METHODS

The study comprised 39 college-age asymptomatic participants (7 men, 32 women) who were randomly assigned to 1 of 2 groups: stretching only (n, 20) and stretching plus posterior joint mobilizations (n, 19). All had a between-shoulder difference of internal rotation of 10° or more. Shoulder internal and external rotation was measured before and after a 4-week intervention period and 4 weeks postintervention. Participants in the stretching-only group performed the cross-body stretch on the limited side. Those in the other group (cross-body stretch plus joint mobilization) were treated with posterior joint mobilization techniques on the limited side.

RESULTS

Overall means for internal rotation of the treated shoulders significantly increased over baseline at the end of the intervention period and at 4 weeks postintervention. External rotation in all shoulders remained unchanged. By the end of intervention, total motion increased significantly from baseline but decreased significantly from the end of intervention to 4 weeks postintervention. Although not statistically significant, the second group (cross-body stretch plus joint mobilization) had greater increases in internal rotation. At 4 weeks postintervention, the second group had maintained its internal rotation gains to a greater degree than those of the stretching-only group.

CONCLUSION

Internal rotation increased in both groups. Inclusion of joint mobilization in a rehabilitation program created trends toward increased shoulder internal rotation mobility.

CLINICAL RELEVANCE

Both methods-cross-body stretch and cross-body stretch plus joint mobilization-may be beneficial for those with limited internal rotation range of motion.

Glenohumeral internal rotation measurements differ depending on stabilization techniques

Background:

The loss of glenohumeral internal rotation range of motion in overhead athletes has been well documented in the literature. Several different methods of assessing this measurement have been described, making comparison between the results of studies difficult.

Hypothesis:

Significant differences in the amount of internal rotation range of motion exist when using different methods of stabilization.

Study Design:

Descriptive laboratory study.

Methods:

Three techniques were used bilaterally in random fashion to measure glenohumeral internal rotation range of motion: stabilization of the humeral head, stabilization of the scapula, and visual inspection without stabilization. An initial study on 20 asymptomatic participants was performed to determine the intrarater and interrater reliability for each measurement technique. Once complete, measurements were performed on 39 asymptomatic professional baseball players to determine if a difference existed in measurement techniques and if there was a significant side-to-side difference. A 2-way repeated-measures analysis of variance was used.

Results:

While interrater reliability was fair between all 3 methods, scapular stabilization provided the best intrarater reliability. A statistically significant difference was observed between all 3 methods (P < .001). Internal rotation was significantly less in the dominant shoulder than in the nondominant shoulder (P < .001).

Conclusion:

Differences in internal rotation range of motion measurements exist when using different methods. The scapula stabilization method displayed the highest intrarater reproducibility and should be considered when evaluating internal rotation passive range of motion of the glenohumeral joint.

Clinical Relevance:

A standardized method of measuring internal rotation range of motion is required to accurately compare physical examinations of patients. The authors recommend the use of the scapula stabilization method to assess internal rotation range of motion by allowing normal glenohumeral arthrokinematics while stabilizing the scapulothoracic articulation.

Shoulder pain in the overhead throwing athlete

Treatment of the overhead throwing athlete is among the more challenging aspects of orthopaedic sports medicine. Awareness and understanding of the throwing motion and the supraphysiologic forces to which the structures of the shoulder are subjected are essential to diagnosis and treatment. Pain and dysfunction in the throwing shoulder may be attributed to numerous etiologies, including scapular dysfunction, intrinsic glenohumeral pathology (capsulolabral structures), extrinsic musculature (rotator cuff), or neurovascular structures. Attention to throwing mechanics and appropriate stretching, strength, and conditioning programs may reduce the risk of injury in this highly demanding activity. Early discovery of symptoms, followed by conservative management with rest and rehabilitation with special attention to retraining mechanics may mitigate the need for surgical intervention. Prevention of injury is always more beneficial to the long-term health of the thrower than is surgical repair. An anatomic approach is used in this report, focusing on common etiologies of pain in the overhead thrower and emphasizing the clinical presentation and treatment.

Rehabilitation of the Overhead Athlete's Elbow

The activities required during overhead sports, particularly during baseball pitching, produce large forces at the elbow joint. Injuries to the elbow joint frequently occur in the overhead athlete because of the large amount of forces observed during the act of throwing, playing tennis, or playing golf. Injuries may result because of repetitive overuse, leading to tissue failure. Rehabilitation following injury or surgery to the throwing elbow is vital to fully restore normal function and return the athlete to competition as quickly and safely as possible. Rehabilitation of the elbow, whether following injury or postsurgical, must follow a progressive and sequential order, building on the previous phase, to ensure that healing tissues are not compromised. Emphasis is placed on restoring full motion, muscular strength, and neuromuscular control while gradually applying loads to healing tissue. In addition, when one is creating a rehabilitation plan for athletes, it is imperative to treat the entire upper extremity, core, and legs to create and dissipate the forces generated at each joint.

A comparison of the musculoskeletal assessments of the shoulder girdles of professional rugby players and professional soccer players

OBJECTIVE

To identify posture types that exist in professional rugby players, and compare them with a population of non-overhead athletes in order to identify possible relationships towards the potential for shoulder injuries.

DESIGN

Observational design Setting: Sports Medicine Clinic Participants: Convenience sample Methodology: Static assessment of posture was carried out in standing, active and passive range of glenohumeral motion, and isometric strength was carried out in accordance with previously recorded protocols.

INTERVENTIONS

Nil Outcome Measures: Observational classification of posture, active and passive range of glenohumeral joint range of motion, isometric strength of selected muscle groups, selected muscle flexibility and Hawkins and Neer impingement tests.

RESULTS

There was a significant difference on range of motion between the two groups (0.025-0.000), isometric middle (0.024-0.005), and lower trapezius (0.01-0.001).

CONCLUSION

There were significant differences between strength and flexibility of muscles around the shoulder girdle between professional rugby players and a control group of professional non-overhead athletes.

Clinical descriptive measures of shoulder range of motion for a healthy, young and physically active cohort

BACKGROUND

The objective of this innovative research study was to describe clinical shoulder complex range of motion (ROM) measures for a young, healthy, and physically active population. This investigation represents a cross-sectional experiment conducted at a military academy-based sports medicine center. Military cadets with no history of shoulder complex injury were assessed within two months of enrollment in the academy; 548 men (18.8 ± 1.0 yr, 75.2 ± 12.2 kg, 178.3 ± 7.4 cm) and 74 women (18.7 ± 0.9 yr, 63.2 ± 8.9 kg, 165.2 ± 6.9 cm) participated. Descriptive measures included cross-body adduction (CAD), flexion (FLX), external rotation (ER0) with the shoulder complex in adduction and elbow flexed to 90°, internal and external rotation (IR, ER) with the shoulder complex at 90° of abduction and elbow flexed to 90° as well as arc (ARC) of IR-ER using standardized clinical quantification techniques. Bilateral and sex differences were evaluated using dependent and independent t-tests, respectively. Percentiles by arm dominance and sex were also calculated for all ROM measures.

RESULTS

Data were normally distributed. Active and passive ROM measures indicated significant bilateral differences (P < 0.05) except for ARC. Sex differences (P < 0.05) were noted for active and passive CAD, FLX and ER0 for the dominant arm as well as active and passive CAD, FLX and ARC for the non-dominant arm.

CONCLUSIONS

These original data provide descriptive measures for shoulder complex ROM excursions, assisting sports medicine practitioners in potentially identifying clinical deficiencies and functional outcomes following shoulder injury.

Arthroscopic capsular plication for microtraumatic anterior shoulder instability in overhead athletes

BACKGROUND

Extreme loading conditions at the glenohumeral joint during overhead athletic activities can result in both soft tissue and osseous adaptative changes at the shoulder. Subtle alterations in the stabilizing structures may lead to anterior instability and debilitating shoulder pain with subsequent inability to participate in athletics. There is currently a paucity of data documenting clinical outcomes after arthroscopic capsular plication in overhead athletes who demonstrate objective findings of pain and anterior instability on physical examination.

PURPOSE

To evaluate outcomes after arthroscopic capsular plication for anterior instability in overhead athletes with an emphasis on postoperative range of motion, postoperative shoulder function, and return to sport.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The authors identified 20 overhead athletes with debilitating shoulder pain and a failed trial of nonoperative management who underwent arthroscopic capsular plication (12 suture plication, 8 suture anchor plication) for anterior instability related to isolated capsular redundancy. Patients were evaluated with the Single Assessment Numerical Evaluation (SANE) and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow Score, and they were interviewed to determine the rate of return to athletic activity. Failures of treatment included patients who demonstrated debilitating pain that precluded return to sport.

RESULTS

At a mean follow-up of 3.6 years (range, 2.0-5.5 years), 18 (90%) patients returned to overhead sports, with 17 (85%) at their preinjury level. The mean (SD) SANE score was 86 (17.5%; range, 30%-100%), and the mean (SD) KJOC score was 82 (18.2; range, 28-100). When compared with the contralateral extremity, there were no significant differences in glenohumeral range of motion. Two patients with associated rotator cuff injury experienced persistent pain with overhead activity and were unable to return to sport, representing a 10% failure rate.

CONCLUSION

Arthroscopic capsular plication for anterior instability related to isolated capsular redundancy is an effective procedure that yields a high rate of patient satisfaction and return to overhead athletic activity with an acceptably low failure rate. Patients with associated rotator cuff injury may be at higher risk for treatment failure.

Effect of different training workload on overhead throwing performance with different weighted balls

The purpose of this study was to investigate the effect of a single and a double training workload with 3-kg medicine ball on the throwing speed in 2-handed overhead throwing movement. Second, what the effect of training with 3-kg medicine balls had on throwing speed with other ball weights. Forty high school students (age 15.9 ± 1.0 year, mass 60.9 ± 9 kg, height 1.68 ± 0.08 m), divided into 3 speed-matched groups, participated in the study. The first group was a control group and did not train any throwing program regimen, whereas the other 2 groups trained overhead throwing with a single (3 series of 6 throws with a 3-kg medicine ball) or double training workload (6 series of 6 throws with a 3-kg medicine ball) for 6 weeks. Throwing speed with 0.35-, 0.45-, 1-, and 3-kg medicine balls was tested before and after a training period of 6 weeks with 2 sessions per week. A significant (p ≤ 0.05) increase in throwing speed was found after the 6-week training period with the 0.35- (5.1%), 1- (3.5%), and 3-kg medicine balls (5.2%) for both training groups, but not with the 0.45-kg ball (0.6%). This increase was mainly caused by the increase of the double workload group. This indicates that training workload is of importance in these subjects for enhancement of ball throwing performance and in designing training programs. Furthermore, that throwing with high enough training volume of throws with a 3-kg medicine ball also can increase ball speed with lighter balls.

Humeral retroversion and its association with posterior capsule thickness in collegiate baseball players

HYPOTHESIS AND BACKGROUND

Baseball players commonly present with decreases in internal rotation (IR) and concurrent increases in external rotation (ER) motion. Several glenohumeral (GH) adaptations have been theorized to cause these changes in motion, including humeral retroversion (HR) and posterior capsule thickness (PCT). However, limited data exist examining the inter-relationship between HR and PCT. Therefore, the purpose of this study was to measure HR, GH IR and ER rotation, and PCT.

MATERIALS AND METHODS

HR and PCT were measured with an ultrasound system (Sonosite Titan; Sonosite, Bothell, WA, USA), and GH IR and ER were measured with a digital inclinometer.

RESULTS

The dominant arm had significantly more HR (15.6°, P = .0001) than the nondominant arm. Pearson correlation coefficients showed a significant negative relationship between HR and GH IR (-0.472, P = .001) and a significant positive relationship between HR and GH ER (0.295, P = .042). A significant positive correlation was also found between HR and PCT (0.427, P = .003).

DISCUSSION

This was the first study to identify a relationship between HR and PCT in addition to GH IR and ER. The identification of these multiple correlations appears to suggest that the loss of IR caused by HR may be placing additional stress on the posterior capsule during the deceleration phase of the throw, thereby causing a fibroblastic healing response.

CONCLUSIONS

HR has previously been identified as a positive adaptation because of the increase in ER without anterior capsule attenuation. However, this study suggests that HR may be contributing to the negative adaptation of PCT.

An acute throwing episode decreases shoulder internal rotation

BACKGROUND

Glenohumeral internal rotation (GIR) and total arc of motion (TAM) decrease, whereas external rotation (GER) may increase in throwing. Although decreased GIR has been documented after throwing, its time course for recovery and the effect of pitching role have not.

QUESTIONS/PURPOSES

We therefore asked (1) how much rotational change occurs after a single throwing episode; (2) do these changes return to baseline by the next throwing episode; and (3) does pitching role affect the amount of change that occurs?

METHODS

Forty-five pitchers, starters and relievers, were examined. GIR and GER measurements were taken at five time points (TP): before throwing (TP1); immediately after throwing (TP2); and 24 (TP3), 48 (TP4), and 72 (TP5) hours later. TAM was calculated as the combination of GIR and GER.

RESULTS

GIR decreased from TP1 to TP5 and did not return to baseline. GER changed very little and TAM decreased at TP5. Relievers had greater GIR, GER, and TAM across all time points, but the amount of change over all time points was not different between groups.

CONCLUSIONS

GIR was most affected over one 4-day throwing cycle after an acute throwing episode and was less than baseline 72 hours later. Pitching role did not affect the short-term changes.

CLINICAL RELEVANCE

GIR changes should be expected after an acute throwing episode and conditioning and recovery programs should be used to modify the changes. Because GIR is dynamic, studies on GIR should specifically state when during the pitching cycle the measurement was obtained.

Glenoid stress distribution in baseball players using computed tomography osteoabsorptiometry: a pilot study

BACKGROUND

It is important to understand the loading conditions when considering the pathology of shoulder disorders in overhead athletes. However, because throwing is a complicated motion and methods to directly determine stress distribution are complex, direct measurement of the stress distribution across the glenohumeral joint has not been attempted. Subchondral bone density reportedly reflects the cumulative stress acting on a joint surface under actual loading conditions.

QUESTIONS/PURPOSES

To assess alterations in stress distribution across the glenoid cavity caused by pitching, we investigated the distribution of subchondral bone density in nonathletic volunteers and asymptomatic baseball players, including fielders and pitchers.

METHODS

We collected CT imaging data from the dominant-side shoulder of 10 nonathletic volunteers (controls), 10 fielders, and 10 pitchers in a competitive college baseball league (all men aged 19–24 years, mean 20.7 years). We measured the distribution of subchondral bone density of the glenoid cavity using CT osteoabsorptiometry. The obtained stress distribution map was divided into four segments: anterosuperior, anteroinferior, posteroinferior, and posterosuperior regions. We quantitatively analyzed the location and percentages of high-density regions on the articular surface.

RESULTS

The percentages of high-density regions, including the anteroinferior and posterior segments, were greater in pitchers and fielders than in controls. The percentages of high-density regions did not differ between pitchers and fielders.

CONCLUSIONS

The bicentric density patterns indicated that the cumulative force of pitching activity affected the long-term stress distribution across the glenoid cavity.

CLINICAL RELEVANCE

Our data should be useful for analyzing pitching activity and clarifying the pathology of shoulder disorders associated with throwing.

Passive range of motion characteristics in the overhead baseball pitcher and their implications for rehabilitation

BACKGROUND

Repetitive overhead throwing motion causes motion adaptations at the glenohumeral joint that cause injury, decrease performance, and affect throwing mechanics. It is essential to define the typical range of motion (ROM) exhibited at the glenohumeral joint in the overhead thrower.

QUESTIONS/PURPOSES

We (1) assessed the glenohumeral joint passive range of motion (PROM) characteristics in professional baseball pitchers; and (2) applied these findings clinically in a treatment program to restore normal PROM and assist in injury prevention.

METHODS

From 2005 to 2010, we evaluated 369 professional baseball pitchers to assess ROM parameters, including bilateral passive shoulder external rotation (ER) at 45° of abduction, external and internal rotation (IR) at 90° abduction while in the scapular plane, and supine horizontal adduction.

RESULTS

The mean ER was greater for the throwing and nonthrowing shoulders at 45° of abduction, 102° and 98°, respectively. The throwing shoulder ER at 90° of abduction was 132° compared with 127° on the nonthrowing shoulder. Also, the pitcher's dominant IR PROM was 52° compared with 63° on the nondominant side. We found no statistically significant differences in total rotational motion between the sides.

CONCLUSIONS

Although we found side-to-side differences for rotational ROM and horizontal adduction, the total rotational ROM was similar.

CLINICAL RELEVANCE

The clinician can use these PROM values, assessment techniques, and treatment guidelines to accurately examine and develop a treatment program for the overhead-throwing athlete.

Shoulder rotational profiles in young healthy elite female and male badminton players

The aim of the present study was to profile shoulder passive range of motion (ROM) and isometric strength for external (ER) and internal (IR) rotation as part of a preseason screening in adolescent national badminton players. Passive external range of motion (EROM) and internal range of motion (IROM) were examined on the dominant and nondominant shoulder in 31 adolescent national badminton players (12 females and 19 males) with a standard goniometer. Muscle strength was examined with a hand-held dynamometer in ER and IR. Total range of motion (TROM = EROM+IROM) was lower on the dominant side compared with the nondominant side in both groups (P < 0.001). Males were generally stronger than females in all strength measurements except for IR on the dominant side (P < 0.01). In females, IR dominant side strength was greater compared with IR on the nondominant side (P < 0.05). TROM was reduced on the dominant side compared with the nondominant side in young elite badminton players, irrespective of gender. No rotational strength differences existed between the dominant and nondominant side in male players, but in female players a higher IR strength on the dominant side was not balanced by a higher ER strength.

Kinetic chain rehabilitation: a theoretical framework

Sequenced physiologic muscle activations in the upper and lower extremity result in an integrated biomechanical task. This sequencing is known as the kinetic chain, and, in upper extremity dominant tasks, the energy development and output follows a proximal to distal sequencing. Impairment of one or more kinetic chain links can create dysfunctional biomechanical output leading to pain and/or injury. When deficits exist in the preceding links, they can negatively affect the shoulder. Rehabilitation of shoulder injuries should involve evaluation for and restoration of all kinetic chain deficits that may hinder kinetic chain function. Rehabilitation programs focused on eliminating kinetic chain deficits, and soreness should follow a proximal to distal rationale where lower extremity impairments are addressed in addition to the upper extremity impairments. A logical progression focusing on flexibility, strength, proprioception, and endurance with kinetic chain influence is recommended.

Voluntary activation deficits of the infraspinatus present as a consequence of pitching-induced fatigue

HYPOTHESIS

Neuromuscular inhibition of the infraspinatus would be greater and external rotation muscle force would be lower after a simulated game compared with pregame values.

MATERIALS AND METHODS

The sample included 21 uninjured, asymptomatic high school-aged baseball pitchers. Maximum volitional shoulder external rotation strength was assessed before and after a simulated game with a clinical dynamometer. Voluntary activation of the infraspinatus was assessed during strength testing by a modified burst superimposition technique. Performance-related fatigue was assessed by monitoring pitch velocity, and global fatigue was assessed by subject self-report before and after the game. Statistical testing included paired and independent t tests, with α ≤ .05.

RESULTS

There was no difference between throwing and non-throwing shoulder external rotation strength (P = .12) or voluntary infraspinatus activation (P = .27) before the game. After the game, voluntary activation was significantly lower in the throwing limb compared with pregame activation levels (P = .01). Lower external rotation strength after the game approached statistical significance (P = .06). Pitch velocity was lower in the final inning compared with first-inning velocity (P = .01), and fatigue was significantly greater after the game (P = .01).

CONCLUSIONS

Voluntary infraspinatus muscle activation is a mechanism contributing to external rotation muscle weakness in the fatigued pitcher. Understanding mechanisms contributing to muscle weakness is necessary to develop effective injury prevention and rehabilitation programs. Treatment techniques that enhance neuromuscular activation may be a useful strategy for enhancing strength in this population.

Critical reflection of the advanced rehabilitation of an elite rugby league player sustaining a posterior Bankart lesion

The following is a critical description and discussion of the successful assessment and rehabilitation of a right shoulder posterior Bankart repair in an elite rugby league player. The rehabilitation follows accelerated, goal based guidelines, widely adopted in current sports practice but not well documented in the literature (Funk & Snow, 2007; Park, Lin, Yokota, & McFarland, 2004). The study serves to be the first critical discussion of such a regime.

REASSESSMENT OF PAINFUL SHOULDERS AMONG BASEBALL PLAYERS AFTER CONSERVATIVE TREATMENT

OBJECTIVE

The objective of this study was to evaluate the rehabilitation results among baseball players who presented pain and medial rotation deficit in their shoulders.

METHODS

Out of 55 baseball players assessed between April and June 2009, it was observed that 20 presented pain at some instant during throwing movements. They were advised to undergo a rehabilitation program with exercises to stretch the posterior capsule and reinforce the muscles of the scapular belt, especially the lateral rotators. Eighteen patients followed the advice, while two were lost from the follow-up. The parameters evaluated were: pain, range of motion, strength before the program and strength after the end of the program.

RESULTS

Comparing the initial and final assessments, we observed mean increases as follows: 10° of elevation (p = 0.001); three vertebral levels of medial rotation (p < 0.001); 20° of medial rotation at 90° abduction (p < 0.001); and 26° of range of motion (p < 0.001). Regarding strength, elevation force increased by 3 kgf (p = 0.002) and lateral rotation force increased by 1 kgf (p = 0.020). Out of the 18 baseball players studied, the pain level improved in 16, while two continued to present pain and underwent magnetic resonance imaging, which showed lesions for surgical treatment.

CONCLUSION

The rehabilitation program conducted among the baseball players was effective and enabled increases in medial rotation, elevation, range of motion and strength of elevation and lateral rotation, consequently producing pain improvements in most of the players.