Rehabilitation for the overhead athlete

Deceleration phase elbow varus moments: a potential injury mechanism for collegiate baseball pitchers

The incidence of elbow injury experienced by baseball pitchers is on the rise. Biomechanical investigations focusing on the acceleration phase of the pitch have yet to elucidate a singular cause for these injuries. Leading to the question is there an additional significant stress on the elbow during other phases of the pitch? This study sought to determine the magnitude of the elbow varus moment during the deceleration phase of the pitching cycle for the fastball, curveball, slider and change-up. Eighty-seven collegiate-level pitchers were evaluated using motion analysis techniques to determine the magnitude of the elbow varus moment occurring during the deceleration phase. The results indicated that the elbow varus moment during the deceleration phase of the pitch was typically between 40% and 50% of the peak acceleration phase moment and was greatest when throwing a slider. Results also indicated that more pitchers experienced deceleration phase moments in excess of 50% of the acceleration moment when throwing breaking pitches. These moments which are the result of the pitchers' need to rapidly decelerate their arm produce an additional significant elbow varus moment that results in additional stress to the elbow.

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.

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.

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.

Data-based interval hitting program for female college volleyball players

CONTEXT

Interval sports programs are a critical rehabilitation element when preparing the injured athlete for a return to preinjury activities. There is currently no published interval hitting program to guide a return to unrestricted play for the volleyball athlete. Therefore, data-based, position-specific overhead hitting programs that control for intensity, time, and number of ball strikes were developed for female college volleyball players.

EVIDENCE ACQUISITION

Records from a single Division I varsity women's volleyball team were examined for all matches during 7 consecutive years of team play. Data were collected for number of hitting and service attempts per game for each position and the number of games per match.

RESULTS

Per game, middle hitters averaged 4.51 attacks and 2.77 service attempts; right-side hitters, 3.58 attacks and 1.26 service attempts; outside hitters, 6.37 attacks and 3.44 service attempts; and setters and defensive specialists, 0.17 attacks and 1.78 service attempts.

CONCLUSION

The interval hitting program can provide rehabilitation specialists with a data-based approach that may facilitate a return to play and minimize the risk of reinjury for volleyball athletes.

Shoulder injuries in the overhead athlete

The overhead throwing motion is an extremely skillful and intricate movement. When pitching, the overhead throwing athlete places extraordinary demands on the shoulder complex subsequent to the tremendous forces that are generated. The thrower's shoulder must be lax enough to allow excessive external rotation but stable enough to prevent symptomatic humeral head subluxations, thus requiring a delicate balance between mobility and functional stability. We refer to this as the "thrower's paradox." This balance is frequently compromised and believed to lead to various types of injuries to the surrounding tissues. Frequently, injuries can be successfully treated with a well-structured and carefully implemented nonoperative rehabilitation program. The key to successful nonoperative treatment is a thorough clinical examination and accurate diagnosis. Rehabilitation follows a structured, multiphase approach, with emphasis on controlling inflammation, restoring muscles' balance, improving soft tissue flexibility, enhancing proprioception and neuromuscular control, and efficiently returning the athlete to competitive throwing. Athletes often exhibit numerous adaptive changes that develop from the repetitive microtraumatic stresses occurring during overhead throwing. Treatment should include the restoration of these adaptations.

LEVEL OF EVIDENCE

Level 5.

Scapular angular positioning at end range internal rotation in cases of glenohumeral internal rotation deficit

STUDY DESIGN

Controlled laboratory study.

OBJECTIVES

Investigate the relationship between glenohumeral internal rotation range-of-motion deficit and 3-dimensional scapular angular positioning during active arm movements in participants with recent participation in overhead sports activity.

BACKGROUND

Subacromial impingement is one of the most common shoulder pathologies and is multifactorial in etiology. Posterior glenohumeral joint capsule tightness has been theorized to contribute to one potential causal factor: abnormal scapular positioning.

METHODS AND MEASURES

Twenty-three subjects, who had participated in competitive sports involving overhead activity within the last 5 years, were categorized into 2 groups based on the degree of glenohumeral internal rotation deficit (20% deficit threshold). Scapular angular positioning of subjects performing shoulder internal rotation from 90 degrees flexion and abduction shoulder positions was evaluated using 3-dimensional electromagnetic surface tracking. Additional sensors monitored trunk and humeral motion. Scapular position data at end range glenohumeral internal rotation, along with glenohumeral internal rotation range of motion measurements, were used to analyze the relationship between glenohumeral internal rotation deficit and scapular position using 2-way ANOVA and regression analyses.

RESULTS

The internal rotation deficit group had significantly greater scapular anterior tilt (9.2 degrees difference, P = .04) across positions, as compared to the control group. Regression analysis demonstrated a significant association between glenohumeral internal rotation deficit and scapular position (tilting) during flexed internal rotation (r(2) = 0.37, P = .03) and for scapular position (anterior tilting and upward rotation) during abducted internal rotation (r = 0.35, P = .036).

CONCLUSIONS

These findings demonstrate a significant relationship between glenohumeral internal rotation deficit and abnormal scapular positioning, particularly increased anterior tilt. This relationship identifies a possible mechanism for development of excessive scapular anterior tilt.

Alterations in Upper Extremity Motion after Scapular-Muscle Fatigue

Objective:

To determine the effect of scapular fatigue on shoulder and elbow kinematics and accuracy.

Design:

Pretest–posttest.

Setting:

Laboratory.

Participants:

30 healthy men.

Interventions:

Subjects performed seated overhead throws into a target before and after a standardized scapular-muscle-fatigue protocol.

Main Outcome Measurements:

Shoulder and elbow kinematic data were analyzed during throwing. Scapular upward rotation was measured (0°, 45°, and 90° humeral elevation in scaption) with an inclinometer. Throwing accuracy was measured as mean error distance from the target (cm).

Results:

After fatigue, there was a significant increase in total elbow motion (12 % more in cocking phase,P< .05) and elbow velocity in the follow-through phase (average and maximum into flexion,P< .05). Throwing accuracy decreased 26% after fatigue (P< .05).

Conclusions:

Scapular-muscle fatigue results in compensatory motions at the elbow that might affect performance and contribute to elbow pathologies.

Eccentric training in chronic painful impingement syndrome of the shoulder: results of a pilot study

Treatment with painful eccentric muscle training has been demonstrated to give good clinical results in patients with chronic Achilles tendinosis. The pain mechanisms in chronic painful shoulder impingement syndrome have not been scientifically clarified, but the histological changes found in the supraspinatus tendon have similarities with the findings in Achilles tendinosis. In this pilot study, nine patients (five females and four males, mean age 54 years) with a long duration of shoulder pain (mean 41 months), diagnosed as having shoulder impingement syndrome and on the waiting list for surgical treatment (mean 13 months), were included. Patients with arthrosis in the acromio-clavicular joint or with large calcifications causing mechanical impingement during horizontal shoulder abduction were not included. We prospectively studied the effects of a specially designed painful eccentric training programme for the supraspintus and deltoideus muscles (3 x 15 reps, 2 times/day, 7 days/week, for 12 weeks). The patients evaluated the amount of shoulder pain during horizontal shoulder activity on a visual analogue scale (VAS), and satisfaction with treatment. Constant score was assessed. After 12 weeks of treatment, five patients were satisfied with treatment, their mean VAS had decreased (62-18, P<0.05), and their mean Constant score had increased (65-80, P<0.05). At 52-week follow-up, the same five patients were still satisfied (had withdrawn from the waiting list for surgery), and their mean VAS and Constant score were 31 and 81, respectively. Among the satisfied patients, two had a partial suprasinatus tendon rupture, and three had a Type 3 shaped acromion. In conclusion, the material in this study is small and the follow-up is short, but it seems that although there is a long duration of pain, together with bone and tendon abnormalities, painful eccentric supraspinatus and deltoideus training might be effective. The findings motivate further studies.

Timing of rotator cuff activation during shoulder external rotation in throwers with and without symptoms of pain

STUDY DESIGN

Fine-wire EMG rotator cuff onset time analysis in 2 matched groups of throwers with and without pain.

OBJECTIVE

To identify if there is a difference in the activation patterns of the rotator cuff muscles during a rapid shoulder external rotation task between throwers with and without pain.

BACKGROUND

The coordinated action of the rotator cuff is recognized as essential for glenohumeral joint control in the throwing athlete. Identification of abnormalities occurring in muscle activation patterns for injured athletes is relevant when prescribing rehabilitative exercises.

METHODS AND MEASURES

Twelve throwers with shoulder pain were compared to a matched group of 11 asymptomatic throwers. Participants were matched for age, height, body mass, and habitual activity. Fine-wire EMG electrodes were inserted into the subscapularis, supraspinatus, and infraspinatus. EMG activity was measured during a reaction time task of rapid shoulder external rotation in a seated position. The timing of onset of EMG activity was analyzed in relation to visualization of a light (reaction time) and to the onset of infraspinatus activity (relative latency).

RESULTS

In the group with shoulder pain, the onset of subscapularis activity was found to be significantly delayed (reaction time, P = .0018; relative latency, P = .0005) from the onset of infraspinatus activity when compared to the control group.

CONCLUSIONS

The presence of shoulder pain in these athletes was associated with a difference in the onset of subscapularis EMG activity during a rapid shoulder external rotation movement. This was an initial step in the understanding of the joint protection mechanisms of the glenohumeral joint and the problems that occur in throwers. This information may assist in providing future guidelines for more effective rehabilitation and prevention strategies for this condition.

Évaluation et rééducation des muscles de l'épaule en isocinétisme : méthodologie, résultats et applications

OBJECTIVE

To evaluate the contribution of isokinetic methods of shoulder strength measurement and training.

METHOD

A Medline search of English and French publications, including referenced articles, allowed us to analyse non-indexed publications. Eighty-seven articles were retained for analysis.

RESULTS

The isokinetic evaluation of the shoulder is valid. Although reproducibility of shoulder evaluation is inferior to that of the knee, it is nevertheless satisfactory when a rigorous test method is used. Normal values for the rotators, abductors-adductors, and extensors-flexors depend on diverse parameters such as age, gender, fat mass, and the type and intensity of physical activity. The agonist to antagonist ratio is particularly informative in pathological conditions. The ratio is modified in cases of impingement syndrome and shoulder instability, and this modification appears to be a cause rather than a consequence of pathologic features. The ratio generally remains modified post-surgery, and normalization must be a major focus of post-surgery rehabilitation.

CONCLUSION

Isokinetic measurement, particularly disturbances in the agonist-antagonist balance, is a reference method for evaluating shoulder muscle strength and detecting deficits in specific muscle groups seen in certain shoulder abnormalities. Such measurement is a valuable tool for orienting rehabilitation towards the deficient muscle groups, complements classical techniques of muscle strengthening, and is an accurate means for following the rehabilitation progress.

Current concepts in the rehabilitation of the overhead throwing athlete

The overhead throwing motion is an extremely skillful and intricate movement that is very stressful on the shoulder joint complex. The overhead throwing athlete places extraordinary demands on this complex. Excessively high stresses are applied to the shoulder joint because of the tremendous forces generated by the thrower. The thrower's shoulder must be lax enough to allow excessive external rotation, but stable enough to prevent symptomatic humeral head subluxations, thus requiring a delicate balance between mobility and functional stability. We refer to this as the "thrower's paradox." This balance is frequently compromised, which leads to injury. Numerous types of injuries may occur to the surrounding tissues during overhead throwing. Frequently, injuries can be successfully treated with a well-structured and carefully implemented nonoperative rehabilitation program. The key to successful nonoperative treatment is a thorough clinical examination and accurate diagnosis. Athletes often exhibit numerous adaptive changes that develop from the repetitive microtraumatic stresses observed during overhead throwing. Treatment should focus on the restoration of these adaptations during the rehabilitation program. In this article, the typical musculoskeletal profile of the overhead thrower and various rehabilitation programs for specific injuries are discussed. Rehabilitation follows a structured, multiphase approach with emphasis on controlling inflammation, restoring muscle balance, improving soft tissue flexibility, enhancing proprioception and neuromuscular control, and efficiently returning the athlete to competitive throwing.

Data-Based Interval Throwing Programs for Baseball Position Players from Age 13 to College Level

Objective:

To design interval throwing programs for baseball players other than pitchers from 13 years of age to the college level.

Design:

The authors recorded throws to base, distance of throws, and perceived effort of throws at 4 levels of play. For catchers they also recorded number of throws to the pitcher, number of sprints to first or third base, and time in the squat stance. From these data they designed throwing programs specific to outfielders, infielders, and catchers.

Results:

No significant difference was found between the number of throws and distance of throws for infielders and catchers across all age groups. The mean distance of throws differed significantly between 13-year-olds and all other levels of play.

Conclusion:

The authors devised 1 program for infielders and catchers of all age groups, 1 program for 13-year-old outfielders, and 1 for all other levels.

Shoulder impingement in tennis/racquetball players treated with subscapularis myofascial treatments

Conservative care of the athlete with shoulder impingement includes activity modification, application of ice, nonsteroidal anti-inflammatory drugs, subacromial corticosteroid injections, and physiotherapy. This case report describes the clinical treatment and outcome of three patients with shoulder impingement syndrome who did not respond to traditional treatment. Two of the three were previously referred for arthroscopic surgery. All three were treated with subscapularis trigger point dry needling and therapeutic stretching. They responded to treatment and had returned to painless function at follow-up 2 years later.

Functional stability of the glenohumeral joint

Normal shoulder function is determined by the stability provided by the passive, active and control subsystems of the joint complex. Given the complexity of the shoulder, it is not surprising that it is one of the most common joints presenting with pathology. Knowledge and understanding of the anatomy and the intricate relationships of each of the subsystems is essential for successful assessment and treatment. This paper presents a review of the anatomy, biomechanics and the integrated function of the glenohumeral joint which are essential for motion. The principles of rehabilitation of dynamic control of the glenohumeral joint are introduced.

Conservative Management of Shoulder Impingement Syndrome in the Athletic Population

Shoulder pain is a common complaint among overhead athletes. Oftentimes, the cause of pain is impingement of the supraspinatus, bicipital tendon, and subacromial bursa between the greater tuberosity and the acromial arch. The mechanisms of impingement syndrome include anatomical abnormalities, muscle weakness and fatigue of the glenohumeral and scapular stabilizers, posterior capsular tightness, and glenohumeral instability. In order to effectively manage impingement syndrome nonoperatively, the therapist must understand the complex anatomy and biomechanics of the shoulder joint, as well as how to thoroughly evaluate the athlete. The results of the evaluation can then be used to design and implement a rehabilitation program that addresses the cause of impingement specific to the athlete. The purpose of this article is to provide readers with a thorough overview of what causes impingement and how to effectively evaluate and conservatively manage it in an athletic population.

Rotator Cuff Training for Pitchers

This paper reviews the role of the rotator cuff during two key phases of the pitching sequence and presents a training program for these muscles. The program uses a periodization design consisting of three stages, beginning with a high-resistance/low-repetition eccentric strengthening stage. This is followed by a low-resistance/high-repetition stage for training muscular endurance. The core exercises for these two stages are prone external rotation in the 90/90 position, prone horizontal abduction, side-lying D2 flexion pattern, supine internal rotation in the 90/90 position, prone elevation with 100° of shoulder abduction and external rotation, and standing scapular plane elevation. The final stage of the program uses high-speed functional exercises: 90/90 external rotation, 90/90 internal rotation, D2 PNF flexion pattern, D2 PNF extension pattern, supine plyometric 90/90 internal rotation with a medicine ball, and the “arm whip” through the D2 PNF flexion pattern. The goal of this program is to prepare the muscles for the stresses of pitching and prevent shoulder injuries.

Glenohumeral joint: internal and external rotation range of motion in javelin throwers

OBJECTIVE

To assess differences in glenohumeral joint rotatory range of movement in javelin throwers between the throwing and non-throwing arm.

METHOD

A universal 360 degrees goniometer was used to assess glenohumeral joint external and internal rotation range in 90 degrees of shoulder abduction in a group of ten senior international javelin throwers.

RESULTS

Both arms had significantly greater degrees of external than internal rotation (p < 0.01), and the throwing arm had significantly greater range of external rotation than the non-throwing arm (p < 0.01).

CONCLUSIONS

The presence of an excessive range of external rotation in the throwing shoulder has the potential to increase eccentric load on the rotator cuff muscles and strain on the passive restraints of the glenohumeral joint. Both of these factors have been implicated in the pathological processes leading to injury in the overhead throwing athlete.

Glenohumeral joint internal and external rotation range of motion in elite junior tennis players

Objective measurement of range of motion of the glenohumeral joint is important for the rehabilitation and prevention of shoulder injury. The primary purpose of this study was to determine whether significant differences exist between the dominant (tennis playing) and nondominant extremity in active internal and external rotation range of motion in elite junior tennis players 11-17 years of age. Two hundred three elite junior tennis players (113 males, 90 females) were bilaterally measured for internal and external rotation at 90 degrees of abduction in a supine position with a specific methodology attempting to isolate glenohumeral motion, while minimizing or negating scapulothoracic motion. A standard universal goniometer was utilized to measure active range of motion (AROM). Dependent t tests were used to compare differences between extremities. No significant difference was found for males or females between the dominant and nondominant arm in external rotation. Analysis of internal rotation (AROM) differences showed significantly less (p < .001) internal rotation (AROM) on the dominant arm for both males and females. Significantly less (p < .001) dominant arm total rotational range of motion was also found in both males and females. The loss of dominant arm internal rotation (AROM) has clinical application for both the development of rehabilitation and preventative flexibility/range of motion programs.

Applications of electromyography in the throwing shoulder

In the complex movement that makes up the baseball pitch, shoulder motion is a single link in an orderly chain of events. It can be argued, though, that herein lies the weakest link and by far the most commonly affected cog in the spectrum of overuse injuries in pitchers. Just why the shoulder receives the brunt of the stress has been the subject of numerous studies in the past several years. The tools of choice in many of these articles have been electromyography and high speed photography which have enabled researchers to study dynamically the phases of the pitch and the sequential firing of the muscles involved. With this information and the knowledge gained from studies looking at muscle activity during specific exercises, the clinician should be able to tailor a rehabilitation program that meets the needs of his or her patient. What has been learned from these articles as applied to the biomechanics of the pitch and the rehabilitation of the athlete who throws and the limitations of this form of study need to be clarified.