Bennett lesions in overhead athletes and associated shoulder abnormalities on MRI.

Abstract

To determine if a Bennett lesion and its size are associated with additional MRI shoulder abnormalities in an overhead athlete. An IRB-approved retrospective review of our database from 1 January 2012 to 1 April 2018 identified 35 overhead athletes with a Bennett lesion on MRI. A control group consisting of 35 overhead athletes without a Bennett lesion were matched for age, level of play (professional vs non-professional), and type of study (arthrogram vs non-arthrogram). Each study was assessed independently by two MSK fellowship trained radiologists. The sizes of the Bennett lesions were measured. Each MRI was assessed for the presence of a labral tear, posterior glenoid cartilage abnormality, humeral head notching or cysts, and fraying or tear of the supraspinatus or infraspinatus tendons. Statistical analyses were performed using Student's t test, Fisher's exact test, and Chi-squared test. There was an increased incidence of posterior glenoid cartilage abnormalities in athletes with Bennett lesions vs those without (23% vs 3%, p value = 0.01). There was no difference in any other MRI abnormalities, including labral tears and findings of internal impingement between these two groups (p value range = 0.09-0.46). There was no association between the size of a Bennett lesion and the presence of glenoid cartilage lesions, labral tears, internal impingement, age, professional status, or need for surgery (p value range = 0.08-0.96). Symptomatic overhead athletes with Bennett lesions have an increased frequency of posterior glenoid cartilage abnormalities, but not labral tears or findings of internal impingement compared to those without Bennett lesions.