Georgiev Georgi P, Kotov Georgi, Iliev Alexandar, Kinov Plamen, Angelova Jordanka, Landzhov Boycho
Department of Orthopedics and Traumatology, University Hospital Queen Giovanna - ISUL, Medical University of Sofia, Sofia, Bulgaria,
Department of Anatomy, Histology and Embryology, Medical University of Sofia, Sofia, Bulgaria.
Cells Tissues Organs. 2018;206(3):165-182. doi: 10.1159/000496985. Epub 2019 Mar 15.
The medial collateral ligament of the knee joint is one of the most commonly injured ligaments of the knee. Recent data have shown that the thin layer of connective tissue covering the ligament, known as the epiligament, is essential for its nutrition and normal function, as well as its healing after injury. The aim of the present study was to investigate and compare the changes in the epiligament of the medial collateral ligament which occurred during operative and non-operative treatment throughout the first month after injury. We used 27 male Wistar rats randomly allocated to three groups. In the 9 rats belonging to the first group, the medial collateral ligament was fully transected and left to heal spontaneously without suture. In the 9 rats belonging to the second group, the transected ends were marked with a 9-0 nylon monofilament suture. The 9 rats in the third group were used as normal controls. Three animals from each group were sacrificed on days 8, 16, and 30 after injury. Light microscopic analysis was performed on semi-thin sections stained with 1% methylene blue, azure II, and basic fuchsin. Transmission electron microscopy was used to study and compare the ultrastructural changes in the epiligament. The statistical analysis of the obtained data was performed using the Kruskal-Wallis H test and Mood's median test. The normal structure of the epiligament of the medial collateral ligament was presented by fibroblasts, fibrocytes, adipose cells, mast cells, collagen fibers, and neuro-vascular bundles. On days 8 and 16 postinjury, the epiligament appeared hypercellular and returned to its normal appearance on the thirtieth day postinjury. The electron microscopic study revealed the presence of different types of fibroblasts with the typical ultrastructural features of collagen-synthetizing cells. The comparative statistical analysis on the respective day showed that there was no statistically significant difference in the number of cells between spontaneously healing animals and animals recovering with suture application. These data further prove that spontaneous healing of the medial collateral ligament yields similar results to surgical treatment and may be used as a basis for the development of treatment regimens with improved patient outcome.
膝关节内侧副韧带是膝关节最常受伤的韧带之一。最近的数据表明，覆盖韧带的结缔组织薄层，即韧带外层，对其营养、正常功能以及损伤后的愈合至关重要。本研究的目的是调查和比较内侧副韧带韧带外层在损伤后第一个月的手术和非手术治疗过程中发生的变化。我们使用了27只雄性Wistar大鼠，随机分为三组。第一组的9只大鼠，内侧副韧带被完全横断，不缝合任其自行愈合。第二组的9只大鼠，横断端用9-0尼龙单丝缝合标记。第三组的9只大鼠作为正常对照。每组在损伤后第8、16和30天处死3只动物。对用1%亚甲蓝、天青II和碱性品红染色的半薄切片进行光镜分析。用透射电子显微镜研究和比较韧带外层的超微结构变化。使用Kruskal-Wallis H检验和Mood中位数检验对所得数据进行统计分析。内侧副韧带韧带外层的正常结构由成纤维细胞、纤维细胞、脂肪细胞、肥大细胞、胶原纤维和神经血管束组成。损伤后第8天和16天，韧带外层细胞增多，损伤后第30天恢复正常外观。电子显微镜研究显示存在具有典型胶原合成细胞超微结构特征的不同类型的成纤维细胞。各天的比较统计分析表明，自行愈合的动物和应用缝合线恢复的动物之间细胞数量没有统计学上的显著差异。这些数据进一步证明，内侧副韧带的自行愈合与手术治疗产生相似的结果，可作为开发改善患者预后的治疗方案的基础。
