|
Journal of Bone and Joint Surgery - British Volume, Vol 87-B, Issue 4,
483-488.
doi: 10.1302/0301-620X.87B4.15684 Copyright © 2005 by British Editorial Society of Bone and Joint Surgery Contact stress at the post-cam mechanism in posterior-stabilised total knee arthroplastyK. Nakayama, MD, Orthopaedic Surgeon1; S. Matsuda, MD, PhD, Assistant Professor, Orthopaedic Surgeon1; H. Miura, MD, PhD, Associate Professor, Orthopaedic Surgeon1; H. Higaki, PhD, Professor, Mechanical Engineer2; K. Otsuka, Mechanical Engineer2; and Y. Iwamoto, MD, PhD, Orthopaedic Surgeon, Professor, Chairman1
1 Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Correspondence should be sent to Assistant Professor S. Matsuda; e-mail: mazda{at}ortho.med.kyushu-u.ac.jp
We measured the contact areas and contact stresses at the post-cam mechanism of a posterior-stabilised total knee arthroplasty when a posterior force of 500 N was applied to the Kirschner Performance, Scorpio Superflex, NexGen LPS Flex Fixed, and NexGen LPS Flex Mobile knee systems. Measurements were made at 90°, 120°, and 150° of flexion both in neutral rotation and 10° of internal rotation of the tibial component. Peak contact stresses at 90°, 120°, and 150° were 24.0, 33.9, and 28.8 MPa, respectively, for the Kirschner; 26.0, 32.4, and 22.1 MPa, respectively, for the Scorpio; and 34.1, 31.5, and 32.5 MPa, respectively, for the NexGen LPS Flex Fixed. With an internally rotated tibia, the contact stress increased significantly with all the fixed-bearing arthroplasties but not with the NexGen LPS Flex Mobile arthroplasty. The post-cam design should be modified in order to provide a larger contact area whilst avoiding any impingement and edge loading. This article has been cited by other articles:
|
|
||||||||||||||||||||||||||||||||||||
