Miyamura Satoshi, Sakai Takashi, Oka Kunihiro, Abe Shingo, Shigi Atsuo, Tanaka Hiroyuki, Shimada Shoichi, Mae Tatsuo, Sugamoto Kazuomi, Yoshikawa Hideki, Murase Tsuyoshi
Departments of Orthopaedic Surgery (S.M., K.O., H.T., T. Mae, H.Y., and T. Murase), Neuroscience and Cell Biology (S.S.), and Orthopaedic Biomaterial Science (K.S.), Osaka University Graduate School of Medicine, Suita, Japan.
Department of Orthopaedic Surgery, Yamaguchi University Graduate School of Medicine, Ube, Japan.
JB JS Open Access. 2019 Jul 31;4(3). doi: 10.2106/JBJS.OA.19.00011. eCollection 2019 Jul-Sep.
During elbow procedures, reconstruction of the joint (including the articular cartilage) is important in order to restore elbow function; however, the regional distribution of elbow cartilage is not completely understood. The purpose of the present study was to investigate the 3-dimensional (3-D) distribution patterns of cartilage thickness of elbow bones (including the distal part of the humerus, proximal part of the ulna, and radial head) in order to elucidate the morphological relationship among them.
Two 3-D surface models were created with use of a laser scanner: (1) a cartilage-bone model based on 20 elderly cadaveric elbows exhibiting normal cartilaginous conditions and (2) a bone model that was created after dissolving the cartilage. The 2 models were superimposed, and cartilage thickness was measured as the interval distance on the articular surface. Measurements were made at categorized anatomical points of the individual bones, and 3-D distributions on the entire articular surface were analyzed. The spatial relationship among individual bones was also assessed.
In the distal part of the humerus, the cartilage was thickest in the intermediate region between the capitellum and the trochlea (mean [and standard deviation], 1.27 ± 0.17 mm); in the proximal part of the ulna, it was thickest at the anterolateral edge of the coronoid (2.20 ± 0.39 mm) and the anteroproximal edge of the proximal sigmoid notch (2.49 ± 0.55 mm); and in the radial head, it was thickest at the articular zone on the rim circumference within the dish (1.10 ± 0.17 mm) and on the proximal circumference around the side (1.02 ± 0.17 mm) (p < 0.001 for all). These thicker cartilage regions gathered on the joint center, facing each other.
The present study demonstrated regional variations in elbow cartilage thickness. The combined findings in individual bones showed "cartilage gathering" at the center of the elbow joint, which we believe to be a novel anatomical finding.
An enhanced understanding of elbow cartilage geometry will provide additional insights into elbow procedures in elderly individuals, such as hemiarthroplasties, in which anatomical contours could help to restore normal joint function and improve postoperative outcomes.
在肘部手术中，关节重建（包括关节软骨）对于恢复肘部功能至关重要；然而，肘部软骨的区域分布尚未完全明确。本研究的目的是调查肘部骨骼（包括肱骨远端、尺骨近端和桡骨头）软骨厚度的三维（3-D）分布模式，以阐明它们之间的形态学关系。
使用激光扫描仪创建了两个三维表面模型：（1）基于20个表现出正常软骨状况的老年尸体肘部的软骨-骨模型，以及（2）溶解软骨后创建的骨模型。将这两个模型叠加，软骨厚度作为关节表面的间隔距离进行测量。在各个骨骼的分类解剖点进行测量，并分析整个关节表面的三维分布。还评估了各个骨骼之间的空间关系。
在肱骨远端，软骨在肱骨小头和滑车之间的中间区域最厚（平均值[和标准差]，1.27±0.17毫米）；在尺骨近端，在冠状突的前外侧边缘（2.20±0.39毫米）和近端乙状切迹的前近端边缘（2.49±0.55毫米）最厚；在桡骨头，在盘内边缘圆周上的关节区域（1.10±0.17毫米）和侧面近端圆周上（1.02±0.17毫米）最厚（所有p<0.001）。这些较厚的软骨区域聚集在关节中心，相互面对。
本研究证明了肘部软骨厚度的区域差异。各个骨骼的综合发现显示在肘关节中心存在“软骨聚集”，我们认为这是一个新的解剖学发现。
对肘部软骨几何形状的深入了解将为老年患者的肘部手术（如半关节置换术）提供更多见解，其中解剖轮廓有助于恢复正常关节功能并改善术后结果。
