Banner Health and University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.
LifeNet Health, Virginia Beach, VA, USA.
J Shoulder Elbow Surg. 2021 Sep;30(9):2146-2155. doi: 10.1016/j.jse.2021.01.019. Epub 2021 Feb 16.
Acellular dermal matrix (ADM) allografts are commonly used in the surgical treatment of complex and irreparable rotator cuff tears. Multiple studies report that superior capsule reconstruction (SCR) using ADM has resulted in short-term clinical success as assessed via radiographic and patient-reported outcomes. However, limited information is available regarding the biologic fate of these grafts in human subjects. This case series describes histologic results from 8 patients who had reoperations, during which the previously implanted ADMs were removed. These explanted ADMs were subjected to histologic analysis with the hypothesis that they would have evidence of recellularization, revascularization, and active remodeling.
Eight patients, 38-82 years old, underwent reoperation 6-38 months after undergoing SCR. ADM explants were voluntarily shipped to the manufacturer for histologic analysis. Each graft's structure and composition were qualitatively evaluated by 1 or more of the following histologic stains: hematoxylin and eosin, safranin O, and Russell-Movat pentachrome. Pan-muscle actin staining also assessed the level of neovascularization, potential myoblast or myocyte infiltration, and muscle tissue development in the graft, and was analyzed to determine the proportion of graft that had been recellularized in situ.
Grafts showed varying levels of gross and microscopic incorporation with the host. An uneven, but high, overall degree of recellularization, revascularization, and active remodeling was observed. The degree of remodeling correlated with implant duration. These results are consistent with successful biologic reconstruction of the superior shoulder capsule.
The present histologic analysis suggests that ADMs used in SCR undergo active recellularization, revascularization, and remodeling as early as 6 months after implantation, and that graft recellularization positively correlates with duration of implantation. These results represent a significant advancement in our knowledge regarding biologic incorporation of ADMs used in SCR.
脱细胞真皮基质（ADM）同种异体移植物常用于复杂和不可修复的肩袖撕裂的外科治疗。多项研究报告称，使用 ADM 进行的上囊重建（SCR）在通过影像学和患者报告的结果评估时取得了短期临床成功。然而，关于这些移植物在人体中的生物命运的信息有限。本病例系列描述了 8 名患者再次手术时的组织学结果，在此期间，先前植入的 ADM 被取出。这些取出的 ADM 进行了组织学分析，假设它们将有再细胞化、再血管化和活跃重塑的证据。
8 名年龄 38-82 岁的患者在接受 SCR 后 6-38 个月接受了再次手术。ADM 移植物被自愿运往制造商进行组织学分析。通过 1 种或多种以下组织学染色（苏木精和伊红、番红 O 和 Russell-Movat 五重染色）对每个移植物的结构和组成进行定性评估。肌动蛋白染色还评估了移植物中的新生血管化水平、潜在的成肌细胞或肌细胞浸润程度以及移植物中的肌肉组织发育，并分析了确定移植物原位再细胞化的比例。
移植物与宿主之间显示出不同程度的大体和微观结合。观察到不均匀但高度整体的再细胞化、再血管化和活跃重塑程度。重塑程度与植入时间相关。这些结果与上肩囊的成功生物重建一致。
目前的组织学分析表明，在植入后 6 个月内，用于 SCR 的 ADM 经历了积极的再细胞化、再血管化和重塑，并且移植物的再细胞化与植入时间呈正相关。这些结果代表了我们对用于 SCR 的 ADM 生物整合的知识的重大进展。
