Rotator Cuff Tendon Repair Morphology Comparing 2 Single-Anchor Repair Techniques

Abstract

To compare the effect of 2 common rotator cuff repair techniques, for smaller tears limited to the use of a single anchor, on tendon morphology in relation to the footprint. Six matched pairs of human shoulders were dissected, and a standardized 10-mm supraspinatus tendon tear was created. Two single-anchor repairs were performed: simple repair with the anchor on the footprint or inverted-mattress repair with the anchor 1 cm distal-lateral to the footprint. The repaired specimens were frozen in situ with liquid nitrogen. Coronal cross sections through the intact and repaired tendon were made. A digitizer was used to measure variables including tendon area and radius of tendon curvature. Comparing between repairs, we found significantly more gap formation for the simple repair at the repair cross section (3.67 ± 0.32 mm v 0.68 ± 0.10 mm, P= .00050). The simple repair had less tendon area (38.28 ± 2.50 mm(2)v 58.65 ± 4.06 mm(2), P= .0036) and a smaller radius of curvature (8.47 ± 1.39 mm v 32.51 ± 3.94 mm, P= .0046). For the simple repair, there was significantly more gap formation, less tendon area, and a smaller radius of tendon curvature for all repair cross sections compared with the intact cross sections (P < .05). For the inverted-mattress repair, there was more gap formation compared with the intact condition (P < .05), although it was less than 1 mm on average; for tendon area, radius of curvature, and tendon height, the cross section centered on the repair showed no differences compared with the intact control. For rotator cuff tears that are 10 mm or smaller and limited to the use of a single anchor, using a distal-lateral anchor position with tape-type suture can provide better maintenance of native tendon morphology and footprint dimensions when compared with repair that uses standard sutures and places the anchor on the footprint. For smaller tears, the inverted-mattress repair described in this article may provide a relatively improved healing environment compared with a simple repair on the footprint, potentially optimizing the prevention of early tear progression.