オカザキ　ケン   Okazaki Ken   岡崎　賢    所属   医学部 医学科（東京女子医科大学病院）    職種   教授・基幹分野長
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Gradual-radius femoral component with s-curve post-cam provides stable kinematics at mid-flexion after total knee arthroplasty.
掲載誌名	正式名：Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association 略　 称：J Orthop Sci ISSNコード：14362023/09492658
掲載区分	国外
巻・号・頁	pp.Epub
著者・共著者	USHIO Tetsuro, HAMAI Satoshi, OKAZAKI Ken, GONDO Hirotaka, IKEBE Satoru, HIGAKI Hidehiko, NAKASHIMA Ysuharu
発行年月	2021/04
概要	BACKGROUND:Mid-flexion instability is the one of the reasons for patient dissatisfaction after total knee arthroplasty (TKA). The purposes of this study were to evaluate in vivo knee kinematics and clinical outcomes using a novel TKA design with a gradual femoral radius component and s-curve post-cam, which are intended to prevent the instability initiated by sudden reductions in the femoral radius observed with conventional components.METHODS:We used radiographic-based, image-matching techniques to analyze femorotibial anteroposterior translation, axial rotation, and anterior/posterior cam-post contact during two dynamic movements, squatting and stair climbing, in 20 knees that had undergone posterior-stabilized fixed-bearing TKA with an improved sagittal profiles of the femoral component and post-cam mechanism. We also evaluated patient-reported outcomes assessed by the 2011 Knee Society Score (KSS 2011).RESULTS:Squatting and stair climbing produced a similar trend in anteroposterior translation and a relatively small standard deviation at mid-flexion. Although the rotation angles varied widely during squatting and stair climbing, the femoral component was consistently externally rotated. Anterior/posterior cam-post contact during squatting and stair climbing were observed in 0/17 knees and 0/0 knees, respectively. The "Symptoms", "Satisfaction", and "Functional activities" subscales of the KSS 2011 were significantly (P < 0.05) improved postoperatively compared to preoperatively ("Symptoms", 10 to 21; "Satisfaction", 15 to 26; "Functional activities", 25 to 71).CONCLUSION:A gradual femoral radius component with an s-curve post-cam provided stable kinematics and favorable clinical results during squatting and stair climbing at 1 year after surgery.
DOI	10.1016/j.jos.2021.02.015
PMID	33933328