Summary

PGA sheet augmentation during ARCR for repairable rotator cuff tears did not show any advantage in terms of clinical outcomes and healing failure; however, it improved the thickness of the repaired tendon.

Abstract

Introduction

Recently, augmentation materials that promote tendon healing in rotator cuff repair have attracted much attention. We have reported good results using polyglycolic acid (PGA) sheets for the reinforcement of massive rotator cuff tears. However, even in cases of repairable rotator cuff tears, healing failure and thinning of the tendon are often observed after repair. We hypothesized that PGA sheet augmentation would be effective in these cases as well. The purpose of this study was to investigate clinical outcomes and MRI changes of the repaired tendon in patients with repairable rotator cuff tears who underwent arthroscopic rotator cuff repair (ARCR) with PGA sheet augmentation.

Methods

This study included 150 patients who underwent ARCR for repairable rotator cuff tears, including the supraspinatus tendon, with at least a two-year follow-up. From 2017 to 2020, the tears were repaired using only the suture bridge technique (group C, 75 patients), and from 2020 to 2022, they were repaired with PGA sheet augmentation (group P, 75 patients). MRIs were taken at 3, 6, and 24 months after surgery, and cuff integrity, repaired tendon thickness, and T2 fat saturation signal intensities (repaired tendon/deltoid ratio, TD ratio) were assessed. Postoperative outcomes, including the Constant-Murley score, the University of California, Los Angeles shoulder score, and pain numerical rating scale, were also assessed preoperatively and two years postoperatively.

Results

There were no significant differences between the two groups in patient background, including age, gender, cuff tear size, and fatty degeneration of cuff muscles. Healing failures were observed in 9 patients (12%) in group C and 5 patients (6.7%) in group P, with no significant difference. The repaired tendon thicknesses were 6.0 ± 1.6 mm and 6.5 ± 1.6mm (P = 0.03) at 3 months, 5.7 ± 1.3mm and 6.0 ± 1.3 mm (P = 0.10) at 6 months, and 5.3 ± 1.2mm and 5.7 ± 1.2mm (P = 0.02) at 24 months after surgery, respectively, showing a decrease in thickness over time in both groups and thicker in group P than in group C at 3 and 24 months. T/D ratios were 1.9 ± 0.7 and 2.0 ± 1.1 at 3 months, 1.9 ± 0.8 and 1.8 ± 0.6 at 6 months, and 1.1 ± 0.6 and 1.1 ± 0.4 at 24 months after surgery, respectively, showing no significant difference between the two groups at all time points. All clinical outcomes were significantly improved after surgery in both groups; however, there was no significant difference between the two groups. There was no infection in either group and no obvious side effects of the PGA sheet.

Discussions
PGA sheet augmentation during ARCR for repairable rotator cuff tears did not show any advantage in terms of clinical outcomes and healing failure. However, the thickness of the repaired tendon was slightly improved by PGA sheet augmentation.