Regarding the “Modified Lasso-Loop Stitch”

I read with interest the Technical Note by Toussaint et al.1 in the June 2009 issue. Knotless approaches to rotator cuff repair represent advancements, arguably as long as biomechanical properties are maintained and clinical outcomes are not compromised. The technique described highlights an efficient way to purchase tissue without having to tie knots during rotator cuff repair, although it does not reduce the number of suture passes required for a simple mattress stitch.

The suture-bridge, or “transosseous-equivalent,” construct for rotator cuff footprint restoration has been shown to have favorable characteristics in the laboratory, as well as clinically.2, 3, 4, 5, 6 The ability to share load between anterior and posterior anchors represents an inherent characteristic to the construct as originally described.7 The concern I have is with Fig 1L in the article. In this schematic, both suture limbs from the lasso loop are fixed anterolaterally, and both simple stitches are anchored posterolaterally. In the context of the concept of “interconnectivity” between anchors and sharing load,6 perhaps a better method would be to fix the posterior lasso-loop end with the anterior simple-stitch end posterolaterally and to do the same for the anterior anchor anterolaterally. As depicted, should the posterolateral fixation become compromised (both simple stitches fixed posterolaterally), both lasso loops would be compromised anteriorly and posteriorly. This is best illustrated in their Fig 1J, in which both simple-stitch ends are used to reduce the lasso-loop ends. If any simple-stitch end is compromised, then the lasso-loop end, although self-locking relative to the tendon, will be compromised relative to the reduction to bone. This reminds me of a recent study in which knotless medial fixation for the transosseous-equivalent repair did not perform as well biomechanically because the suture would cut through the tendon.8 Should either simple-stitch end cut through, even partially, the corresponding lasso-loop end will lose some degree of security to the footprint. Perhaps with symmetric lateral fixation (lasso loop and simple stitch fixed to the same anchor laterally), this potential problem will be less likely with respect to the overall construct. What do the authors think about lasso loops at both ends? Would this compromise the reduction maneuver? Although technically demanding, what about repeating the construct with double-loaded anchors (without doubling the number of lateral anchors) for the construct described, thus augmenting the posterolateral fixation?

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Figure 1. (L) The anterolateral anchor is in place, and the suture-bridge repair is complete. This is a representation of a right shoulder with the patient in the beach-chair position with 3 to 5 ports placed posteriorly, posterolaterally, laterally, anterolaterally, and anteriorly as needed for appropriate instrumentation. (J) The cuff is reduced and the post is created with the simple stitch. The arrows show the reduction maneuver.

The authors should be commended for improving on stitch configuration, because this is potentially the simplest, most efficient way to improve different rotator cuff repair constructs. I would encourage a laboratory study to delineate the biomechanical effect of such a configuration in this setting, and a report on the authors' clinical series would be most appreciated.