Rotator cuff tears occur in over 30% of individuals aged older than 60 years, with 150,000 to 200,000 rotator cuff repairs (RCRs) performed annually in the United States. Although numerous case series have shown excellent clinical outcomes, failure rates after RCR vary widely from 5% to 94%. Although RCR was historically performed by an open approach, surgeons have transitioned to the arthroscopic approach to reduce surgical morbidity. Early comparative studies showed high failure rates with arthroscopic repairs, which were thought in part to be due to the inability of single-row (SR) repairs to restore the footprint.
Double-row (DR) RCRs came about in response to these concerns. DR repair uses both medial-and lateral-row anchors to facilitate improved coverage of the rota- tor cuff footprint with the supraspinatus, and early reports showed retear rates of 11% to 22%. More recently, several authors have recommended augmenting DR repairs with suture connections between the medial and lateral rows using a transosseous-equivalent (TOE) technique to compress the tendon to the foot- print. Although some biomechanical analyses have shown DR and TOE repairs to have increased contact area, decreased gap formation, and increased load to failure, others have been less conclusive. Randomized clinical trials (RCTs) and controlled clinical trials (Level I to Level III evidence) are conflicted as to whether DR fixation affects structural healing or clinical outcomes. To attempt to resolve this conflict, numerous authors have systematically reviewed the existing RCTs and controlled clinical trials with or without meta-analysis. Although some of these studies have concluded that DR RCR provides superior structural healing to SR RCR, others have concluded that no difference exists and SR is thus superior because it is less expensive and less technically demanding intraoperatively. Similarly, whereas some of these systematic reviews have concluded that DR RCR provides superior clinical outcomes to RCR, others have concluded that no difference exists except in the setting of large to massive tears (>3 cm). Meta-analysis of Level I RCTs theoretically provides the highest available level of evidence for clinical decision making, but how shall we proceed when the highest available evidence conflicts?
The purpose of this study was (1) to conduct a systematic review of meta-analyses comparing SR and DR RCR, (2) to propose a guide through the currently discordant best available evidence to provide treatment recommendations, and (3) to highlight gaps in the literature that require future research.