キタダ　マサアキ   KITADA MASAAKI   北田　容章    所属   関西医科大学  解剖学講座    職種   教授
論文種別	原著(症例報告除く)
言語種別	英語
査読の有無	査読あり
表題	Downsizing effect of a modular radial head prosthesis on the lateral collateral ligament of the elbow: A cadaveric study
掲載誌名	正式名：Clinical biomechanics 略　 称：Clin Biomech ISSNコード：02680033
掲載区分	国外
巻・号・頁	80,pp.105140
著者・共著者	Hatta T, Shinagawa K, Kawakami J, Yamamoto N, Kitada M, Itoi E
発行年月	2020/12
概要	Background: It remains unclear how the head and stem diameters for the radial head prosthesis could affect mechanical properties of the lateral collateral ligament measured by strain changes during elbow and forearm motions. Methods: Eight cadaveric specimens were secured to the device, which allows elbow flexion-extension and forearm pro-supination. Using six different implant combinations comprising 2 sizes for the head (long- and short-axis of the native head) and 3 sizes for the stem (press-fit, -1 mm, and -2 mm downsizing), prostheses were attached via the posterior approach. A differential variable reluctance transducer placed on the central portion of the radial collateral ligament were used for strain measurement with elbow flexion at 0°, 30°, 60°, and 90°. At each position, the strain patterns with the forearm in the neutral and 45° pro-supination positions were also assessed. Findings: Specimens implanted with long-axis head component showed greater increases in the ligament strain during elbow flexion than intact specimens or those implanted with short-axis head. Compared to press-fit stem, implants with downsizing to -1 mm approximated strain patterns during pro-supination with elbow extension to intact condition. Interpretation: Morphologic variation of the head and stem components in radial head prostheses led to altered strain patterns in the lateral collateral ligament during elbow and forearm motions. A short-axis head component can be used to prevent excessive strain changes after the prosthesis application. Downsizing of the stem component might be an option for approximating the biomechanics at the radiocapitellar joint during forearm rotation to the intact elbow.
DOI	10.1016/j.clinbiomech.2020.105140
PMID	32745705