Document Type

Article

Publication Date

2008

Keywords

Cancellous bone; Distal femur; Apparent modulus; Bone mineral apparent density; Femoral knee components

Abstract

Early loosening and implant migration are two problems that lead to failures in cementless (press-fit) femoral knee components of total knee replacements. To begin to address these early failures, this study determined the anterior–posterior mechanical properties from four locations in the human distal femur. Thirty-three cylindrical specimens were removed perpendicular to the press-fit surface after the surgical cuts on 10 human cadaveric femurs (age 71.5 ± 14.2 years) had been made. Compression testing was performed that utilized methods to reduce the effects of end-artifacts. The bone mineral apparent density (BMAD), apparent modulus of elasticity, yield and ultimate stress, and yield and ultimate strain were measured for 28 cylindrical specimens. The apparent modulus, yield and ultimate stress, and yield and ultimate strain each significantly differed (p<0.05) in the superior and inferior locations. Linear and power law relationships between superior and inferior mechanical properties and BMAD were determined. The inferior apparent modulus and stresses were higher than those in the superior locations. These results show that the press-fit fixation characteristics of the femoral knee component differ on the anterior shield and posterior condyles. This information will be useful in the assignment of mechanical properties in finite element models for further investigations of femoral knee components. The property–density relations also have applications for implant design and preoperative assessment of bone strength using clinically available tools.

Journal

Journal of Biomechanics

DOI

10.1016/j.jbiomech.2007.11.018

Volume

41

Issue

5

Pages

1077-1085

Publisher

Elsevier

Rights

Copyright © 2008 Elsevier

Comments

This is peer-reviewed accepted manuscript of the article published in the Journal of Biomechanics, 41(5):1077-1085. DOI https://doi.org/10.1016/j.jbiomech.2007.11.018

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.

Share

COinS