In this very good study, Connolly et al. compared noncontrast magnetic resonance imaging (MRI) scans with shoulder arthroscopy in the diagnosis of Type-II superior labral anterior-posterior (SLAP) lesions. The patients were selected from the practices of sports fellowship-trained surgeons in a community setting, although the radiology reports were done by both musculoskeletal fellowship-trained radiologists and those without such training (i.e., generalists). This study found low sensitivity and high specificity for the diagnosis of Type-II SLAP tears on MRI, given that noncontrast MRI scanning was used and a difference in sensitivities was found between musculoskeletal fellowship-trained radiologists and those who did not have such training.
One major issue is that there is no gold standard for the diagnosis of Type-II SLAP lesions. Even if there were a gold standard, many sports and shoulder surgeons do not agree. For example, in the case of a sixty-two-year-old woman with a rotator cuff tear who also has a Type-II SLAP tear, some would say the symptoms are related to the Type-II SLAP tear; however, the symptoms are coming from the rotator cuff tear only so the surgeon should repair only the cuff tear and leave the SLAP tear alone. Another example is a forty-four-year-old man with a Type-II SLAP lesion with labral detachment from the superior rim, but his symptoms were obviously from the biceps tendinitis; the surgeon may opt to treat the biceps lesion and not necessarily repair the SLAP tear, even if it might exist morphologically. At the Annual Meeting of the American Orthopaedic Society for Sports Medicine in July 2011, there was discussion that throwers and overhead athletes with symptoms of SLAP tears were more likely to need repair of the SLAP tear, whereas those who have other symptoms were less likely to need SLAP surgery. Given the lack of a consistent gold standard, any study based on this reasoning could be inherently flawed, since the importance and impact of SLAP tears are subjective and there is no consensus on management.
Fortunately, the authors thought the objective of this study was not to determine the prevalence of SLAP lesions but rather to examine the accuracy of MRI in the diagnosis of confirmed SLAP lesions requiring treatment. SLAP lesions that were present but not repaired were not a part of the study population and do not affect the objective of the study. Franceschi et al., in a study in The American Journal of Sports Medicine, agree that a repair of a Type-II SLAP lesion is not indicated in all patients1.
Weber et al. reviewed the cases of SLAP lesions and repairs in the American Board of Orthopaedic Surgery Part-II database from 2003 to 2008 and indicated concern for the increased rate of SLAP repairs by members of our sports medicine and shoulder societies. Many believe that the need for a SLAP repair is overdiagnosed, and I agree this is a valid point. Even in the current study, in which some patients did not need surgery, the four surgeons (all with sports fellowship training) performed 417 SLAP repairs during the five-year period. Therefore, some will think that even those patients were overdiagnosed for surgery, and it could diminish the findings in the study.
Nonetheless, this study describes a realistic clinical practice in many ways, including the community setting versus an academic medical center. Also, the musculoskeletal fellowship-trained radiologists had significantly higher sensitivities in accurately diagnosing the lesion than did the radiologists without such training. While not everyone who interprets shoulder MRI studies is a musculoskeletal fellowship-trained radiologist, we do need to become better at diagnosing the true pathologic cause of shoulder pain in these patients. Currently, given the findings of this study, noncontrast MRI is not a reliable diagnostic tool for Type-II SLAP lesions in a community setting.