Partial-Thickness Rotator Cuff Tears

>> Partial-thickness rotator cuff tears (PTRCTs) are a common pathology with a likely high asymptomatic incidence rate, particularly in the overhead athlete. >> The anatomy, 5-layer histology, and relationship to Ellman's classification of PTRCTs have been well studied, with recent interest in radiographic predictors such as the critical shoulder angle and acromial index. >> Depending on the definition of tear progression, rates of PTRCT progression range from 4% to 44% and appear related to symptomatology and work/activity level. >> Nearly all PTRCTs should be managed conservatively initially, particularly in overhead athletes, with those that fail nonoperative management undergoing arthroscopic debridement +/- acromioplasty if <50% thickness or arthroscopic conversion repair or in situ repair if >50% thickness. >> Augmentation of PTRCTs is promising, with leukocyte-poor platelet-rich plasma having the most robust body of supportive data. Mesenchymal signaling cell biologics and the variety of scaffold onlay augments require more rigorous studies before regular usage.