“How Urgent Is This Rotator Cuff Surgery, Doctor?”

Commentary In general, a surgical procedure may be indicated to address an active issue or to prevent a larger problem for the patient down the road. Given that the success rate with rotator cuff repair deteriorates as the tears enlarge and the muscles atrophy and become replaced by fat, the motivations for operative management of the rotator cuff often fall into both categories. However, with the lengthy rehabilitation following rotator cuff repair, especially for an athlete or a laborer, many patients with a full-thickness rotator cuff tear, although symptomatic, seek guidance on the risks of delaying the surgical procedure until a time that might be more convenient for them to undergo repair and complete the postoperative course. Hochreiter et al. should be saluted for their article that provides facts and figures that are a critical step forward in counseling patients on this commonly encountered scenario. The authors prospectively enrolled 77 patients (79 shoulders) with full-thickness rotator cuff tears that, because either the surgeons or the patients elected for nonoperative management, were not treated with rotator cuff repair. Instead, the patients were followed with a repeat surveillance magnetic resonance imaging (MRI) scan. Fatty infiltration (FI) of the supraspinatus (SSP), FISSP, was quantitatively assessed on both MRI scans, and the risk factors for relevant progression of this FISSP were evaluated. Significant risk factors (and odds ratios [ORs]) for relevant FI progression based on the initial MRI scan were a tear size of ≥20 mm in the mediolateral dimension (OR, 19); quantitative FI percentage of ≥9.9%, very roughly correlating with a grade of 2 on the Goutallier grading scale as modified by Fuchs et al.1 (OR, 17.5); and tear size of ≥17 mm in the anteroposterior dimension (OR, 8). The simultaneous presence of all of these risk factors together yields a predicted 91% chance of relevant progression of FISSP at a mean of 19.5 months. A patient with these poor predictive factors may not want to wait to address the rotator cuff tear. Multiple studies have evaluated the risk factors for rotator cuff tear progression, most notably the longitudinal ultrasound studies by Yamaguchi et al.2,3, but, although these studies have been instrumental in the understanding of the natural history of rotator cuff tear size progression, they have lacked quantitative assessments of the FISSP progression or the risk factors underpinning this critical variable. Identified risk factors of qualitative FISSP progression are numerous, including patient age, initial tear size, tear enlargement, and anterior cable involvement, but the methodology utilized by Hochreiter et al. and very recently described by Xu et al.4 allows for the quantitative assessment of FISSP by averaging voxels on multiple MRI sections of the SSP to improve on the less-than-optimal interobserver and intraobserver reliability of the Goutallier-Fuchs scale. As a prospective study, it would have been helpful to have the MRI scans at regular intervals in the study by Hochreiter et al. rather than the actual range of 3 to 55 months (mean, 14.5 months). However, surprisingly, there was only a weak correlation between the FISSP and the time between MRI scans. Perhaps this is because the interval between the tear and the first clinical presentation and MRI is unknown; thus, we do not know where in the natural history of each rotator cuff tear these 2 snapshots were taken. However, we can say that the size of the tear and the amount of FISSP were more important than the length of time in determining FISSP progression. Further study is clearly needed to definitively answer these clinically important questions, but this study is a glimpse into the future of rotator cuff research and already provides some critical statistics that can help patients and surgeons to choose the appropriate timing for rotator cuff repair.