Matsunaga E
Department of Orthopaedic Surgery, School of Medicine, Fukuoka University.
Igaku Kenkyu. 1991 Jan;61(1):1-19.
We designed a new non constrained total shoulder prosthesis and examined it biomechanically. In order to adapt the shoulder prosthesis for the Japanese, fifty skeletal and one hundred radiographs shoulder joints of Japanese were measured. In radiographs we also measured curvature radius of the humeral head and glenoid fossa. We studied force analysis to elucidate the stability of gleno humeral joint using Rigid Body Spring Model. The result on this study indicate that to lengthen the glenoid surface and to make it near the same radius head and glenoid the joint stability will become stable. Our total shoulder prosthesis consist of a cobalt alloy humeral component, a cobalt alloy glenoid component and a high density polyethylene++ outer head put over a small head of humeral component. The glenoid component have two variations. One is for anatomical replacement and its central angle is 78 degrees. The other is for poor function of rotator cuff and its central angle is 110 degrees. The results of biomechanical experiments showed possibility and advantages of our non constrained total shoulder prosthesis being put into clinical practice.
我们设计了一种新型非约束性全肩关节假体，并对其进行了生物力学研究。为了使肩关节假体适合日本人，我们测量了50具日本骨骼标本和100张日本肩关节X线片。在X线片中，我们还测量了肱骨头和关节盂的曲率半径。我们使用刚体弹簧模型研究了力分析，以阐明盂肱关节的稳定性。该研究结果表明，延长关节盂表面并使其半径与肱骨头相近，关节稳定性将得到增强。我们的全肩关节假体由一个钴合金肱骨头部件、一个钴合金关节盂部件和一个置于肱骨头部件小头之上的高密度聚乙烯++外头组成。关节盂部件有两种变体。一种用于解剖学置换，其中心角为78度。另一种用于肩袖功能不良，其中心角为110度。生物力学实验结果表明，我们的非约束性全肩关节假体应用于临床具有可能性和优势。
