Sites of Kinetically Critical Femoral Head Roughening for Third Body Acceleration of Total Hip Implant Wear

2004 ◽  
Author(s):  
Hannah J. Lundberg ◽  
Kristofer J. Stewart ◽  
Thomas D. Brown
Keyword(s):  
Finite Element ◽  
Femoral Head ◽  
Aseptic Loosening ◽  
Fe Model ◽  
Third Body ◽  
Hip Implant ◽  
Total Hip ◽  
Head Surface ◽  
Sliding Distance ◽  
Implant Wear

Polyethylene debris shed during the use of total hip implants can result in debris-induced aseptic loosening. This aseptic loosening is the leading cause of implant failure. Total hip implant wear is highly variable and can be accelerated by third body ingress and subsequent roughening of the metal femoral head counterface. Up to 40% of clinical wear rate variance may be attributable to third body effects [1]. It is hypothesized that the location of counterface roughening will have dramatic effects on the induced implant wear. Using a previously validated sliding-distance-coupled contact finite element (FE) model of total hip implant wear [2], we identified regions of the femoral head surface that, when roughened, result in maximal wear. By implication, these are the sites most important to protect from third body access.

Development and Validation of a Finite Element Model of Wear in Uhmwpe Liner Using Experimental Data From Hip Simulator Studies

2021 ◽  
Author(s):  
Nihal Kottan ◽  
Gowtham N H ◽  
Bikramjit Basu
Keyword(s):  
Finite Element ◽  
Femoral Head ◽  
Wear Rate ◽  
Contact Pressure ◽  
Correction Factor ◽  
Linear Wear ◽  
Maximum Relative Error ◽  
Fe Model ◽  
3D Point Clouds ◽  
Dynamic Wear

Abstract The wear of acetabular liner is one of the key factors determining the longevity and osseointegration of Total Hip Replacement (THR) implants. The long-term experimental measurements of wear in THR components are time and cost-intensive. A finite element (FE) model of a 32 mm Ceramic on Polymer system consisting of ZTA (Zirconia-toughened Alumina) femoral head and UHMWPE (Ultrahigh molecular weight polyethylene) liner was developed to predict the dynamic wear response of the liner. Archard-Lancaster equation, consisting of surface contact pressure, wear rate, and sliding distance, was employed to predict the wear in the liner. The contact pressure and wear at the articulating surface were found to decrease over time. A new computational method involving 3D point clouds from the FE analyzed results were used to construct wear maps. The model was able to predict the linear wear with relative errors ranging from 9% to 36% over 2 million cycles when compared to the published results. The increasing error percentage occurring primarily from the use of a constant wear rate was reduced to a maximum of 17% by introducing a correction factor. Volumetric wear rate was predicted with a maximum relative error of 7% with the implementation of the correction factor. When the model was implemented to study liners of diameters ranging from 28 mm to 36 mm, the linear wear was seen to decrease with an increase in femoral head diameter, which is in agreement with the clinical data.

Aseptic Loosening of Total Hip Implant: Mechanisms of Osteolysis and Potential Therapy

2010 ◽  
Vol 17 (3) ◽  
pp. 82-88
Author(s):  
M A Berglezov ◽  
Tat'yana Mikhaylovna Andreeva ◽  
M A Berglezov ◽  
T M Andreeva
Keyword(s):  
Aseptic Loosening ◽  
Hip Implant ◽  
Total Hip

scholarly journals Finite element modeling of proximal femur with quantifiable weight-bearing area in standing position

2020 ◽  
Author(s):  
Yang Peng ◽  
Tian-Ye Lin ◽  
Jing-Li Xu ◽  
Hui-Yu Zeng ◽  
Da Chen ◽  
...  
Keyword(s):  
Finite Element ◽  
Femoral Head ◽  
Proximal Femur ◽  
Physical Phenomenon ◽  
Weight Bearing ◽  
Positional Distribution ◽  
Standing Position ◽  
Fe Model ◽  
X Ray ◽  
Weight Bearing Area

Abstract BackgroundThe positional distribution and size of the weight-bearing area of femoral head in the standing position as well as the direct active surface of joint force can directly affect the result of finite element (FE) stress analysis, however in most studies related separate FE models of femur, the division of this area is vague, imprecise and un-individualized. The purpose of this study was to quantify the positional distribution and size of the weight-bearing area of femoral head in standing position by a set of simple methods, to realize individualized reconstruction of proximal femur FE model.MethodsFive adult volunteers were recruited for X-ray and CT examination in the same simulated bipedal standing position with a specialized patented device. We extracted these image data, calculated the 2D weight-bearing area on X-ray image, reconstructed the 3D model of proximal femur based on CT data, and registered them to realize the 2D weight-bearing area to 3D transformation as the quantified weight-bearing surface. One of the 3D models of proximal femur was randomly selected for finite element analysis (FEA), and we defined three different loading surfaces, and compared their FEA results.ResultsA total of 10 weight-bearing surfaces in 5 volunteers were constructed, they were mainly distributed on the dome and anterolateral of femoral head with crescent shape, in the range of 1,218.63mm2 - 1,871.06mm2. The results of FEA showed stress magnitude and distribution in proximal femur FE models among three different loading conditions were significant differences, the loading case with quantized weight-bearing area was more in accordance with the physical phenomenon of the hip.ConclusionThis study confirmed an effective FE modeling method of proximal femur, which can quantify weight-bearing area to define more reasonable load surface setting without increasing the actual modeling difficulty.

The influence of shape and sliding distance of femoral head movement loci on the wear of acetabular cups in total hip arthroplasty

2002 ◽  
Vol 216 (6) ◽  
pp. 393-402 ◽  
Author(s):  
D Bennett ◽  
J F Orr ◽  
D E Beverland ◽  
R Baker
Keyword(s):  
Femoral Head ◽  
Aspect Ratio ◽  
Hip Joint ◽  
Wear Rates ◽  
Total Hip ◽  
Aspect Ratios ◽  
Average Aspect Ratio ◽  
Sliding Distance

Wear of the polyethylene acetabular component is the most serious threat to the long-term success of total hip replacements (THRs). Greatly reduced wear rates have been reported for unidirectional, compared to multidirectional, articulation in vitro. This study considers the multidirectional motions experienced at the hip joint as described by movement loci of points on the femoral head for individual THR patients. A three-dimensional computer program determined the movement loci of selected points on the femoral head for THR patients and normal subjects using kinematic data obtained from gait analysis. The sizes and shapes of these loci were quantified by their sliding distances and aspect ratios with substantial differences exhibited between individual THR patients. The average sliding distances ranged from 10.0 to 18.1 mm and the average aspect ratios of the loci ranged from 2.5 to 9.2 for the THR patients. Positive correlations were found between wear rate and average sliding distance, the inverse of the average aspect ratio of the loci and the product of the average sliding distance and the inverse of the average aspect ratio of the loci. Patients with a normal hip joint range of motion produce multidirectional motion loci and tend to experience more wear than patients with more unidirectional motion loci. Differing patterns of multidirectional motion at the hip joint for individual THR patients may explain widely differing wear rates in vivo.

scholarly journals Predicting revision risk for aseptic loosening of femoral components in total hip arthroplasty in individual patients—A finite element study

2007 ◽  
Vol 25 (6) ◽  
pp. 779-788 ◽  
Author(s):  
Alexander B. Lennon ◽  
John R. Britton ◽  
Ruairi F. MacNiocaill ◽  
Damien P. Byrne ◽  
Patrick J. Kenny ◽  
...  
Keyword(s):  
Finite Element ◽  
Total Hip Arthroplasty ◽  
Aseptic Loosening ◽  
Hip Arthroplasty ◽  
Total Hip ◽  
Finite Element Study ◽  
Revision Risk ◽  
Element Study

scholarly journals Optimized trapezoidal-shaped hip implant for total hip arthroplasty using finite element analysis

2020 ◽  
Vol 7 (1) ◽  
pp. 1719575
Author(s):  
Chethan K N ◽  
Mohammad Zuber ◽  
Shyamasunder Bhat N ◽  
Satish Shenoy B ◽  
Duncan Shepherd
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Total Hip Arthroplasty ◽  
Hip Arthroplasty ◽  
Element Analysis ◽  
Hip Implant ◽  
Total Hip

Optimal Material Selection for Total Hip Implant: A Finite Element Case Study

2019 ◽  
Vol 44 (12) ◽  
pp. 10293-10301 ◽  
Author(s):  
Abdullah Tahir Şensoy ◽  
Murat Çolak ◽  
Irfan Kaymaz ◽  
Fehim Findik
Keyword(s):  
Finite Element ◽  
Material Selection ◽  
Hip Implant ◽  
Total Hip ◽  
Selection For ◽  
Optimal Material

Local Head Roughening as a Factor Contributing to Variability of Total Hip Wear: A Finite Element Analysis

2002 ◽  
Vol 124 (6) ◽  
pp. 691-698 ◽  
Author(s):  
Thomas D. Brown ◽  
Kristofer J. Stewart ◽  
John C. Nieman ◽  
Douglas R. Pedersen ◽  
John J. Callaghan
Keyword(s):  
Wear Rate ◽  
Adhesive Wear ◽  
Polyethylene Wear ◽  
Bearing Surface ◽  
Third Body ◽  
Element Analysis ◽  
Wear Factor ◽  
Total Hip ◽  
Key Factor ◽  
Sliding Distance

Large inter-patient variability in wear rate and wear direction have been a ubiquitous attribute of total hip arthroplasty (THA) cohorts. Since patients at the high end of the wear spectrum are of particular concern for osteolysis and loosening, it is important to understand why some individuals experience wear at a rate far in excess of their cohort average. An established computational model of polyethylene wear was used to test the hypothesis that, other factors being equal, clinically typical variability in regions of localized femoral head roughening could account for much of the variability observed clinically in both wear magnitude and wear direction. The model implemented the Archard abrasive/adhesive wear relationship, which incorporates contact stress, sliding distance, and (implicitly) bearing surface tribology. Systematic trials were conducted to explore the influences of head roughening severity, roughened area size, and roughened area location. The results showed that, given the postulated wear factor elevations, head roughening variability (conservatively) typical of retrieval specimens led to approximately a 30° variation in wear direction, and approximately a 7-fold variation in volumetric wear rate. Since these data show that randomness in head scratching can account for otherwise-difficult-to-explain variations in wear direction and wear rate, third-body debris may be a key factor causing excessive wear in the most problematic subset of the THA population.

Sign in / Sign up

Export Citation Format

Share Document