Localized Rotator Cuff Tendon Degeneration for Cadaveric Shoulders with and Without Tears Isolated to the Supraspinatus Tendon

Abstract

Localized differences in tissue degeneration throughout intact and torn rotator cuff tendons have not been well quantified. The objective of this study was to investigate histological differences in localized degeneration in tendons with and without rotator cuff tears isolated to the supraspinatus tendon. Four intact shoulders and four shoulders with rotator cuff tears isolated to the supraspinatus tendon were dissected down to the infraspinatus and supraspinatus tendons. Biopsies were taken throughout the tendon insertion, mid‐substance, myotendinous junction, and around the tear if present. Samples were stained with hematoxylin and eosin and tendon degeneration was graded based on collagen fiber organization, nuclei shape, cellularity, and lipoid degeneration. Comparisons in degeneration parameters were made based on the tendon type (supraspinatus vs. infraspinatus), location within the tendon, and presence of a tear. Supraspinatus tendons exhibited more degeneration than the infraspinatus tendon (P < 0.05). Significant increases in lipoid degeneration were found near the myotendinous junction compared to the rest of the tendon (P < 0.001). Tendons with rotator cuff tears showed greater amounts of lipoid degeneration compared to intact tendons (P = 0.03). A strong negative correlation was found between lipoid degeneration and collagen fiber organization (r = −0.922, P = 0.001). No differences in degeneration were found between medial, anterior, and posterior edges of the tear. The study highlights specific factors of tendon degeneration contributing to the local differences in tendon degeneration. By understanding local differences in tendon degeneration, surgical protocols for repair can be improved. Clin. Anat., 33:1007–1013, 2020. © 2019 Wiley Periodicals, Inc.

First immunohistochemical evidence of human tendon repair following stem cell injection: A case report and review of literature

“…With respect to the latter, the morphological appearance of regions 3 and 4 in Figure 3 and regions B and C in Figure 4 - 15 is in line with descriptions of the morphological appearance of degenerative supraspinatus tendon tissue at various degrees in the literature[ 49 - 51 ]. Additionally, to our knowledge, spots within tendons with morphological appearance and immunohistochemical characterization as the one observed in the second part of the biopsy (Panels D in Figure 4 - 15 ) have not previously been described in the scientific literature.…”

First Immunohistochemical Evidence of Human Tendon Repair Following Stem Cell Injection: A Case Report and Review of Literature

“…With respect to the latter, the morphological appearance of regions 3 and 4 in Figure 3 and regions B and C in Figures 4-15 is in line with descriptions of the morphological appearance of degenerative supraspinatus tendon tissue at various degrees in the literature [49][50][51] . Additionally, to our knowledge, spots within tendons with morphological appearance and immunohistochemical characterization as the one observed in the second part of the biopsy (Panels D in Figures 4-15) have not previously been described in the scientific literature.…”

Association of Severe Histological Degeneration of the Torn Supraspinatus Tendon and Retear After Arthroscopic Repair of Full-Thickness Rotator Cuff Tears Using the Suture Bridge Technique

“…In the cadaveric study by Ferrer et al, 6 similar amounts of tendon degeneration parameters (cellularity, fiber organization, and nuclei shape) were observed for intact and torn supraspinatus tendons, indicating that tendon degeneration likely occurs before the RC tear. Another cadaveric study showed similar results.…”

“…However, a previous cadaveric study demonstrated that no significant differences were observed in degeneration, fiber organization, nuclei shape, and cellularity by location (insertion, midsubstance, myotendinous junction, and the medial, anterior, and posterior edges of the tear). 6 Fourth, the evaluation of clinical findings in this study was based on the UCLA score, which was originally designed to evaluate shoulder arthroplasty, although there are reports of its use for RC surgery. 1,27 Fifth, the postoperative follow-up period was relatively short for the analysis of clinical outcomes after surgery.…”