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

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.