Summary

This study showed that angiogenesis after superior capsule reconstruction (SCR) using fascia lata autograft initiated at the periphery of the bursal-side graft and progressed into the graft itself without any correlations between blood flow volume and pain-related clinical outcomes, suggesting that angiogenesis after SCR resulted from the healing process but not pain-related inflammation.

Abstract

Introduction

Arthroscopic superior capsule reconstruction (SCR) with a fascia lata autograft for the patients with irreparable rotator cuff tears leads to greater improvement in clinical and structural outcomes compared to that using acellular dermal allografts, highlighting the importance of graft healing in achieving favorable clinical outcomes. To date, it remains unclear 1) when and where graft angiogenesis occurs after SCR and 2) whether angiogenesis results from graft healing or pain-related inflammation. This study therefore aimed to investigate temporal changes in angiogenesis and blood flow volume after SCR, and to evaluate the association between angiogenesis and pain-related clinical outcomes.

Methods

We prospectively studied 30 patients (15 men and 15 women; mean age: 67.5 years) with irreparable rotator cuff tears who underwent SCR using a fascia lata autograft with an intermuscular septum between 2021 and 2023. The rate of cases with angiogenesis and blood flow volume in the periphery of the bursal-side graft (perigraft) and within the graft itself on the greater tuberosity and humeral head were evaluated using Fealy’s scoring system (0–3 points) with power Doppler ultrasound at 6 weeks and 3, 6, and 12 months postoperatively. Shoulder pain was evaluated using the visual analog scale (VAS) at the same time points. Neer’s and Hawkins’ impingement tests were performed at 6 and 12 months. McNemar test and Wilcoxon rank-sum test with Holm adjustment were used to examine temporal changes in the rate of cases with angiogenesis and blood flow scores. Spearman’s rank correlation and Fisher’s exact test were used to examine correlations between angiogenesis or blood flow score and pain-related clinical outcomes.

Results

The rate of cases with angiogenesis and blood flow scores in the perigraft was highest at 6 weeks postoperatively, then significantly decreased at 12 months (6 weeks, 90% and 1.2 points; 3 months, 80% and 0.9 points; 6 months, 83% and 1.1 points; and 12 months, 47% and 0.6 points; P<0.01 and P=0.04, respectively). Angiogenesis within the graft on the greater tuberosity significantly increased at 3 months, and blood flow scores peaked at 6 months (6 weeks, 43% and 0.3 points; 3 months, 77% and 0.9 points; 6 months, 80% and 1.3 points; and 12 months, 67% and 0.4 points; all P<0.05) Angiogenesis within the graft on the humeral head also significantly increased at 3 months (P=0.03), with no significant temporal changes in the blood flow scores (6 weeks, 50% and 0.4 points; 3 months, 77% and 0.6 points; 6 months, 73% and 1.0 points; and 12 months, 53% and 0.6 points). No significant correlations were observed between blood flow score and VAS scores (P=0.16–0.99) or between angiogenesis and the positive rate of impingement tests (P=0.24–1.0).

Conclusion

Angiogenesis initially occurred in the perigraft and progressed to the graft itself following SCR using fascia lata autograft. Blood flow volume within the graft peaked at 6 months postoperatively but did not correlate with shoulder pain or positive impingement tests, indicating that angiogenesis following SCR is more likely part of the healing process rather than pain-related inflammation.