Chronic adaptations of the long head of the biceps tendon and groove in professional baseball pitchers

Editorial Commentary: Outcomes After SLAP Repair and Biceps Tenodesis Are Unpredictable for Throwing Athletes With SLAP Lesions

SLAP tears have been associated with pain, poor performance, and missed playing time for decades. Treatment of SLAP tears in the throwing athlete, particularly baseball pitchers, remains a significant challenge. As few as 7% of baseball players are able to return to elite-level performance after a SLAP repair. The throwing athlete must repeatedly orchestrate a sequence of rotational, accelerating, and decelerating movements to produce a throw with sufficient velocity and control to perform at an elite level. Repetitive overhead stress leads to physiologic adaptations in shoulder motion and structure but can also generate biceps labral complex pathology. Recommendations of SLAP repair for young competitive athletes and biceps tenodesis for middle-aged recreational athletes or salvage cases may be grounded in dogma more than evidence. The line between the young and middle-aged athlete may be blurring; many world-class athletes compete into their late 30s and early 40s. Current literature shows massive variability in outcomes after each procedure. Return to sport for throwers after SLAP repair or biceps tenodesis remains completely unpredictable.

Chronic Adaptations of the Shoulder in Baseball Pitchers: A Systematic Review

BACKGROUND

Understanding clinical and tissue adaptations to the throwing shoulder is important for optimizing injury prevention and rehabilitation programs in baseball players.

PURPOSE/HYPOTHESIS

The purpose of this study was to determine the chronic clinical (range of motion [ROM] and strength) and tissue adaptations of the throwing shoulder in baseball pitchers. It was hypothesized that the throwing shoulder would have increased external rotation (ER) ROM and decreased internal rotation (IR) ROM compared with the nonthrowing shoulder, but that calculations of soft tissue glenohumeral IR deficit (GIRD) and soft tissue ER gain (ERG) would show that the true soft tissue restrictions were instead in the direction of ER ROM.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using various keywords related to the shoulder and baseball. Studies were included if chronic adaptations of the shoulder were evaluated bilaterally in nonrecreational baseball pitchers. Outcomes of interest collected include IR and ER ROM measured in 90° of shoulder abduction, humeral retroversion (HR), GIRD, ERG, and various structural adaptations. All other chronic adaptations were compiled and reported qualitatively because of the heterogeneity of variables assessed.

RESULTS

Overall, 1273 studies were screened and 36 met final inclusion criteria, with 24 studies (67%) evaluating professional pitchers. Across 13 studies and 1101 professional pitchers, the mean clinical GIRD was 10.0° and the mean clinical ERG was 6.5°, leading to a total arc of ROM deficit of 3.5° in the throwing shoulder. Across 498 included pitchers with HR measures, the mean bilateral difference in HR was 15.4°. After calculating soft tissue GIRD, 3 of 4 studies found that pitchers do not have any soft tissue restrictions in IR ROM. In contrast, after calculating soft tissue ERG, all 4 studies found pitchers to have soft tissue restrictions in ER ROM with a mean of 8° to 13°.

CONCLUSION

When isolating for soft tissue restrictions through calculation of soft tissue GIRD and ERG, previously reported IR ROM deficits are currently not as prevalent, and soft tissue restrictions in ER ROM are now being observed. Clinicians should focus on better isolating soft tissue restrictions to evaluate whether an athlete has deficits in IR or ER ROM.

How to Expose the Long Head of the Biceps Tendon in Shoulder Arthroscopy Efficiently: The Tubercle-Traction and Touch-Tendon Method

Arthroscopic tenodesis of the long head of the biceps tendon (LHBT) is a common procedure in a series of bicipital tendinopathies, including tendinitis, SLAP lesions, and tendon instability. Locating and exposing the LHBT during arthroscopy present a technical challenge in tenodesis. Blind exploration of the subacromial space may result in inadvertent tendon transection and iatrogenic damage to surrounding structures, leading to increased patient trauma, bleeding, and operation time. Using the tubercle-traction and touch-tendon method facilitates a roadmap-style, accurate, prompt exposure of the LHBT, minimizing blind exploration-related damage to the subacromial bursal area and adjacent structures, which is conducive to early and rapid postoperative shoulder recovery for patients.

Adaptive pathology: new insights into the physical examination and imaging of the thrower's shoulder and elbow

Throwing with high velocity requires extremes of glenohumeral external rotation of the abducted arm where particularly high forces in the shoulder and elbow are endured. Repeated throwing leads to dominant-arm bony remodeling of the humerus, glenoid, and elbow, and multiple soft tissue changes that would be considered abnormal. Many of these features are thought to be adaptive and protective. The purpose of this work is to (1) define the concept of adaptive pathology; (2) review the mechanics of the throwing motion; (3) review pertinent physical examination and imaging findings seen in asymptomatic throwers' shoulders and elbows and describe how these changes develop and may be adaptive-allowing the thrower to perform at high levels; and then (4) review the principles of surgical treatment in the throwing athletes, which should focus on reducing symptoms, but not necessarily restoring the thrower's anatomy to normal.

The Correlation between Variation of Labral Attachment and Lesions of the Long Head of the Biceps Tendon in Patients with Rotator Cuff Tears

OBJECTIVE

There was no universally accepted classification system that describes LHBT lesions as a type of its' pathology in patients with shoulder pain. This study aimed to determine the correlation of anatomic variants of glenoid labrum attachment of long head of biceps tendon (LHBT) and to assess their association, if any, with its lesions in rotator cuff tear (RCT) patients.

METHODS

All RCT patients from January 2016 to December 2019 were assessed arthroscopically to classify the LHBT labrum attachment according to its' anatomical location. A simplified classification was created to describe the LHBT as normal, tendinitis, subluxation or dislocation, partial tear and superior labral tear from anterior to posterior (SLAP) lesion beyond type II The RCT were classified as three types as partial, small to medium and large to massive. The correlation of variants of LHBT labral attachment with type of LHBT lesions in different RCT groups was evaluated.

RESULTS

In total, 669 patients were included for evaluation. The attachment of the LHBT was entirely posterior in 23 shoulders (3.4%), posterior-dominant in 81 shoulders (12.1%), and equal in 565 shoulders (84.4%). In equal distribution LHBT attachment group, age > 60 (odds ratio: 2.928, P < 0.001) and size of RCT (P < 0.001) were significant risk factors of LHBT lesions. In the analysis of all patients, comparing with the partial thickness rotator cuff tear (PTRCT), the odds ratio of small to medium RCT and large to massive RCT was 2.398 and 6.606 respectively. In addition, age > 60 (odds ratio: 2.854, P < 0.001) and size of RCT (P < 0.001) were significant risk factors of LHBT lesions. In posterior dominant group, size of RCT was a significant risk factor of LHBT lesions but not any others (P < 0.001). In entirely posterior group, no risk factor of LHBT lesions was found. It showed that the variation of LHBT attachment was not a significant risk factor of LHBT lesions in rotator cuff repaired patients (p = 0.075).

CONCLUSIONS

There are three types of LHBT labrum attachment in RCT patients on arthroscopic observation. 84.4% were equal distribution of LHBT attachment on glenoid labrum, followed by posterior-dominant (12.1%) and entirely posterior type (3.4%) in present study. Although the variation of LHBT attachment was not a significant risk factor of LHBT lesion in rotator cuff repaired(RCR) patients, there were different risk factors among three LHBT labral attachment types. In RCR patients, age > 60 and RCT size were significant risk factors of LHBT lesions.

Individualizing the Throwing Progression Following Injury in Baseball Pitchers: the Past, Present, and Future

PURPOSE OF REVIEW

A critical component of any rehabilitation program following injury is a graduated exposure of pathologic or vulnerable tissue to sport-specific stressors. A foundational aspect in the return to sport process following an injury in baseball athletes is the development of an interval throwing program. A shift has occurred in recent years from generic programs to individualized progressions. The current review explores the evolution of interval throwing program construction and discusses the possibilities of the future with advancements in technology and understanding.

RECENT FINDINGS

Early interval throwing programs relied primarily on pre-determined throwing distance and volume to estimate total training load while following a fixed throwing schedule. Currently, clinicians have begun to utilize available technology in attempts to determine training prescription and obtain more accurate estimates of stresses placed upon the body. Thus, interval throwing programs have become more individualized and flexible to account for each athlete's individual differences and biological response to training. Future development may be able to predict specific internal response to stressors and proactively adjust training load to maximize positive adaptations while minimizing any maladaptive events. As with all concepts and principles within the realm of athlete rehabilitation, clinicians must continue to adapt how they conceptualize and develop individualized interval throwing programs for the overhead throwing athlete. We will continue to see a shift away from a responsive approach to a proactive one, where clinicians can utilize modern technologies to precisely prescribe a throwing dosage based upon expected tissue response within the athlete.