Biomechanical Analysis of Proximal Fitting-Distal Filling Stem and Proximal Fitting- Distal Tapered Stem in Cementless Hip Prosthesis: A 3 Dimensional Finite Element Study.
- Author:
Sung Kon KIM
1
;
Jong Woong PARK
;
Joon Seok HONG
;
Jae Hoon KIM
;
Soo Won CHAE
;
Jae Won PARK
Author Information
1. Department of Orthopaedic Surgery College of Medicine, Ansan Hospital, ansan, korea.
- Publication Type:Original Article
- Keywords:
Cementless total hip replacement;
Micromotion;
Stress distribution;
Stress shielding;
Proximal fitting-distal filling stem;
Proximal fitting-distal tapered stem;
3-D finite element models
- MeSH:
Arthroplasty, Replacement, Hip;
Femur;
Gait;
Hip Prosthesis*;
Hip*;
Humans;
Leg;
Postoperative Period;
Tomography, X-Ray Computed
- From:The Journal of the Korean Orthopaedic Association
2001;36(3):279-286
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: This study was undertaken to compare the initial micromotion and stress shielding of a "fit and fill" stem to a "proximal fitting and distal tapered" stem in the early postoperative period using the load simulating single leg stance and stair climbing. MATERIALS AND METHODS: Using the data from 3-D human CT scan, authors developed two types of 3-dimensional finite element total hip replacement model of proximal femur, which were inserted with a "fit and fill" stem and a "proximal fitting and distal tapered" stem. The constructions of stems were based on the OmnifitTM stem (about 13,000 element & 20,000 nodes). We compared micromotion, maximal principal stress and strain energy of each stems. RESULTS: The results indicate that micromotion in a fit and fill stem were slightly lower than that of a tapered stem, especially in stair climbing over that in the single leg stance. The maximum principal stress on the cortex of femur was slightly higher in a tapered stem in the case of single leg stance, and 2 times higher in the case of stair climbing. Strain energy also was much higher in a tapered stem in both single leg stance and stair climbing gait. CONCLUSION: These findings indicate that a tapered stem design could provide more favorable biomechanical benefits rather than a fit & fill stem after cementless total hip replacement.
