Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, USA.
Department of Orthopaedic Surgery, The Steadman Clinic, Vail, Colorado, USA.
Am J Sports Med. 2023 Jul;51(8):2030-2040. doi: 10.1177/03635465231171680. Epub 2023 May 26.
The healing capacity of the human glenoid labrum varies by tear location. Current evidence suggests that the healing capacity of meniscal and cartilage injuries relates to cellular composition and vascularity. However, little is known about the histological characteristics of the glenoid labrum and how they may affect healing potential in specific anatomic regions.
Regenerative characteristics of the glenoid labrum differ based on the anatomic region.
Descriptive laboratory study.
Human glenoid labra from fresh unpreserved cadavers were transversely sectioned in different anatomic regions. Masson trichrome stain was used to determine dense and loose extracellular matrix regions and vessel densities. Hematoxylin and eosin, Ki-67+, and CD90+/CD105+ stains were performed to determine total, proliferative, and progenitor cell densities, respectively. Regression models demonstrated relationships between vascular area, progenitor cell quantity, and probability of successful operation.
Among all labral aspects, the superior glenoid labrum had the highest percentage (56.8% ± 6.9%) of dense extracellular matrix or avascular tissue ( < .1). The vascular region of the superior labrum had the fewest total cells (321 ± 135 cells/mm; < .01) and progenitor cells (20 ± 4 cells/mm; < .001). Vascular area was directly correlated with progenitor cell quantity ( = .006002). An increase in probability of successful operation was associated with a linear increase in vascular area ( = 0.765) and an exponential increase in progenitor cell quantity ( = 0.795). Subsequently, quadratic models of vascularity and progenitor cell quantity around the labral clock were used to assess relative healing potential. Quadratic models for percentage vascular area ( = 6.35e-07) and weighted progenitor cell density ( = 3.03e-05) around the labral clock showed that percentage vascular area and progenitor cell quantity increased as labral tissue neared the inferior aspect and diminished near the superior aspect.
Anatomic regions of the glenoid labrum differ in extracellular matrix composition, vascularity, and cell composition. The superior glenoid labrum is deficient in vascularity and progenitor cells, which may explain the high failure rates for repairs in this location.
Improved understanding of the composition of distinct glenoid labral positions may help to improve therapeutic strategies for labral pathology.
人类肩盂唇的愈合能力因撕裂位置而异。现有证据表明，半月板和软骨损伤的愈合能力与细胞组成和血管有关。然而，对于肩盂唇的组织学特征以及它们如何影响特定解剖区域的愈合潜力知之甚少。
肩盂唇的再生特征因解剖区域而异。
描述性实验室研究。
从新鲜未保存的尸体中横向切取不同解剖区域的人肩盂唇。使用 Masson 三色染色来确定致密和疏松细胞外基质区域以及血管密度。进行苏木精和伊红、Ki-67+和 CD90+/CD105+染色，以分别确定总细胞、增殖细胞和祖细胞密度。回归模型表明血管面积、祖细胞数量与手术成功率之间的关系。
在所有肩盂唇方面，上肩盂唇的致密细胞外基质或无血管组织（<0.1）比例最高（56.8%±6.9%）。上肩盂唇的血管区域总细胞数最少（321±135 个细胞/mm；<0.01）和祖细胞数最少（20±4 个细胞/mm；<0.001）。血管面积与祖细胞数量直接相关（=0.006002）。手术成功率的提高与血管面积的线性增加（=0.765）和祖细胞数量的指数增加（=0.795）相关。随后，使用时钟状肩盂唇周围的血管和祖细胞数量的二次模型来评估相对愈合潜力。时钟状肩盂唇周围的血管面积百分比（=6.35e-07）和加权祖细胞密度（=3.03e-05）的二次模型表明，随着肩盂唇组织接近下侧，血管面积和祖细胞数量百分比增加，而在接近上侧时减少。
肩盂唇的解剖区域在细胞外基质组成、血管和细胞组成方面存在差异。上肩盂唇的血管和祖细胞数量不足，这可能解释了该位置修复失败率高的原因。
对不同肩盂唇位置组成的更好理解可能有助于改善肩盂唇病理的治疗策略。
