Load to Failure and Stiffness Anchor Placement and Suture Pattern Effects on Load to Failure in Rotator Cuff Repairs

Rotator cuff tendinopathy is a frequent cause of shoulder pain and can cause a decrease in shoulder strength and range of motion. Tears of the rotator cuff tendon can be repaired open or arthroscopically. In general, arthroscopic rotator cuff repair (RCR) has been found to have similar clinical outcomes when compared with the open technique.4,14,16,30 Some studies have shown a higher rate of tear recurrence with an open surgical technique compared with arthroscopy when patients were examined by magnetic resonance imaging (MRI)4 or ultrasonography.11 Many different repair techniques for arthroscopic RCR have been described as the orthopaedic community strives to maximize tissue integrity and healing to optimize clinical strength and rehabilitation and to reduce tear recurrence.1,7,10,15,19,22,28 Historically, RCR has been performed using the single-row configuration that consists of suture anchors placed at the anatomic footprint of the rotator cuff.31 Failure rates of the standard single-row arthroscopic RCR have led surgeons to develop alternative fixation methods such as the double-row technique.4 This technique consists of the placement of medial row anchors at the lateral margin of the articular cartilage and placement of lateral row anchors in the lateral aspect of the footprint. Use of the double-row repair allows for a more anatomical restoration of the footprint,5,21,22 increased tendon-to-bone contact area,29 decreased gap formation after cyclic loading,27 and improved initial fixation strength.1,15,19 In a study by Ma et al,19 double-row fixation constructs had a significantly higher ultimate load than 3 types of single-row configurations: 287 N versus 191, 212, and 250 N.19 Ahmad et al1 reported that double-row repair had significantly less gapping than single-row repair. However, other biomechanical studies found that there was no difference in load to failure or gap formation between single- and double-row repairs.11,19 One such study showed that increasing strength was due to an increase in the number of sutures.13 Clinically, some studies have found no difference in outcomes between single- and double-row repair techniques.6,9 However, a systematic review of clinical arthroscopic rotator cuff repair studies (ranging from 1994 to 2009) found that, in general, the double-row repair techniques had a significantly lower retear rate compared with single-row repair techniques.8 Another clinical study showed that, for similarly sized tears, the double-row repair technique exhibited improved radiographic healing compared with the single-row technique.24 The purpose of this study was to compare 5 different types of suture patterns while maintaining equality in number of anchors. Using the suture bridge technique as a baseline guide, each configuration used 4 anchors. The 5 different techniques and suture configurations were as follows: (1) single-row repair with simple stitch, (2) single-row repair using a modified Mason-Allen technique, (3) double-row modified Mason-Allen technique, (4) double-row cross-bridge technique, and (5) double-row transosseous-equivalent technique with suture bridge. Our hypothesis was that the Mason-Allen–crossed cruciform transosseous-equivalent technique, configuration 3, is superior to other suture configurations while maintaining equality in suture limbs and anchors.