Superior Bennett lesion: a bone fragment at the posterosuperior glenoid rim in 5 athletes

Thrower's Exostosis of the Shoulder: A Systematic Review With a Novel Classification

Background:

A variety of thrower’s exostoses are grouped under the term Bennett lesion, which makes understanding diagnosis and treatment difficult.

Purpose:

To identify all types of reported thrower’s and overhead athlete’s exostoses and categorize them into a classification system to allow a morphology-based classification.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review of all articles pertaining to Bennett lesions and thrower’s exostosis was performed. The classification and treatments were evaluated to describe the types, proposed causes, diagnosis, and treatment options.

Results:

A total of 27 studies were included in the systematic review. The anatomic locations referenced in the study demonstrated posteroinferior, posterior, and posterosuperior glenoid lesions. Aggregate radiographic data demonstrated 158 of 306 patients (52%) with a thrower’s exostosis of any type and location. Of these 158 patients with a radiographic lesion, 119 (75%) patients were symptomatic. The locations were posteroinferior in 110 patients (70%), directly posterior in 2 patients (1.3%), posterosuperior in 44 patients (28%), and unknown in 2 patients (1.3%). Avulsed lesions were present in 9 (5.7%) posteroinferior lesions, 0 direct posterior lesions, and 2 (1.3%) posterosuperior lesions. Treatment plans included both nonoperative and operative strategies, but operative intervention was more commonly reported for detached lesions. After operative intervention, only 61% of reported athletes returned to preinjury performance.

Conclusion:

Based on a comprehensive review of the literature, we identified several anatomic locations for a thrower’s exostosis beyond the classic Bennett lesion. We categorized the reported exostoses into a new classification system for description of location and type (subperiosteal or free fragment) of the thrower’s exostosis, which may be used to study future treatments. Current treatment strategies recommend that surgical treatment of thrower’s exostosis is considered only after exhausting nonoperative management because reported return to sport is variable after surgery. The effectiveness of excision or repair for both subperiosteal and detached lesions has not been established.

Prevalence of Bennett lesions based on sex, ancestry, and age in an osteologic collection of 5,662 scapulae

BACKGROUND

Bennett lesions represent an extra-articular ossification on the posteroinferior aspect of the glenoid fossa and a potential source of posterior shoulder pain and limitation. The prevalence of Bennett lesions in the general population is unknown.

MATERIALS AND METHODS

A total of 5,662 scapulae from 2,831 individual cadaveric specimens greater than 18 years of age at the time of death were examined. Matching scapulae were evaluated for Bennett lesions by two independent authors. Lesion prevalence was calculated and statistical analysis performed to evaluate differences in prevalence based on specimen sex (males vs. females), ancestry (African-American vs. Caucasian) and with increasing age at the time of death.

RESULTS

Bennett lesions were observed in 3.5% (n = 98 of 2,831) of specimens and 1.8% (n = 104 of 5,662) of scapulae. Interobserver reliability was 0.83, indicating excellent agreement among authors. Males possessed significant higher odds of possessing a Bennett lesion when compared to females (p = .009) and African-American specimens when compared to Caucasian specimens (p < .001). Each additional year of age was associated with a 1.4% increase in odds of a specimen having a Bennett lesion, while no significant increase in Bennett lesion prevalence was appreciated with increasing specimen age at the time of death when comparing male to female specimens (p = .07) or African-American to Caucasian specimens (p = .73).

CONCLUSIONS

Bennett lesions were identified in 3.5% of osseous specimens and 1.8% of scapulae, with significantly higher prevalence in male and African-American specimens.

Upper extremity physeal injury in young baseball pitchers

Adolescent baseball players, especially pitchers, are at increased risk for shoulder and elbow injuries as their level of competition increases. The intersection of the adolescent growth spurt with the high levels of elbow valgus and shoulder rotational torques placed upon the arm during overhand pitching predisposes the shoulder and elbow to physeal injuries. Little League shoulder and Little League elbow syndromes most commonly represent pathology at the physeal regions of the proximal and distal humerus and proximal ulna sustained from repetitive loads caused by overhead throwing. There is a growing understanding that these injuries occur on a wide spectrum from delayed physeal closure and physeal widening to acute transphyseal fracture. Although operative intervention is infrequently required, patient and parent counseling can be complex. Health care professionals who care for adolescent baseball players also can play an important role in prevention. Appropriate counseling requires a comprehensive understanding of the clinical, radiographic, and biomechanical aspects of these injuries. This review summarizes these major concepts, focusing on the best available evidence from recent biomechanical and clinical studies on shoulder and elbow injuries in adolescent baseball pitchers.

Imaging of shoulder injuries in sports medicine: current protocols and concepts

The shoulder joint has a wide breadth of derangements that can occur with sports activity. Whether the mechanism of injury is acute or the sequela of repetitive microtrauma, recent advances in musculoskeletal imaging and the understanding of athletic shoulder trauma will hopefully steer the clinician and radiologist alike to the proper diagnosis. Injury is inevitable. When it occurs, the clinician cognizant of the current concepts and protocols in the imaging of shoulder injury will be better prepared to diagnose and subsequently treat these disorders.