Design and test of hip stem for medullary revascularization

Yang, Chu‐Wen; Wei, Hung-Wen; Kao, Hung-Yu; Cheng, Cheng‐Kung

doi:10.1016/j.medengphy.2009.06.001

Cited by 21 publications

(19 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The longer distance between the loading point (proximal end) and the hip joint fixation point (distal end) induces larger bending stresses on the whole joint at distal end. Previous results show that the resultant Von Mises stresses at similar Ti alloy stem range from 186 MPa to 253 MPa [7,34]. The present results show that the possible maximum Von Mises stress at stem is 212 MPa, which occurs in case of 220 mm CoCrMo stem.…”

Section: Resultssupporting

confidence: 51%

In vitro assessment of Function Graded (FG) artificial Hip joint stem in terms of bone/cement stresses: 3D Finite Element (FE) study

Al-Jassir

Fouad

Alothman

2013

BioMedical Engineering OnLine

View full text Add to dashboard Cite

BackgroundStress shielding in the cemented hip prosthesis occurs due to the mismatching in the mechanical properties of metallic stem and bone. This mismatching in properties is considered as one of the main reasons for implant loosening. Therefore, a new stem material in orthopedic surgery is still required. In the present study, 3D finite element modeling is used for evaluating the artificial hip joint stem that is made of Function Graded (FG) material in terms of joint stress distributions and stem length.Method3D finite element models of different stems made of two types of FG materials and traditional stems made of Cobalt Chromium alloy (CoCrMo) and Titanium alloy (Ti) were developed using the ANSYS Code. The effects on the total artificial hip joint stresses (Shear stress and Von Mises stresses at bone cement, Von Mises stresses at bone and stem) due to using the proposed FG materials stems were investigated. The effects on the total artificial hip joint system stresses due to using different stem lengths were investigated.ResultsUsing FG stem (with low stiffness at stem distal end and high stiffness at its proximal end) resulted in a significant reduction in shear stress at the bone cement/stem interface. Also, the Von Mises stresses at the bone cement and stem decrease significantly when using FG material instead of CoCrMo and Ti alloy. The stresses’ distribution along the bone cement length when using FG material was found to be more uniform along the whole bone cement compared with other stem materials. These more uniform stresses will help in the reduction of the artificial hip joint loosening rate and improve its short and long term performance.ConclusionFE results showed that using FG stem increases the resultant stresses at the femur bone (reduces stress shielding) compared to metallic stem. The results showed that the stem length has significant effects on the resultant shear and Von Mises stresses at bone, stem and bone cement for all types of stem materials.

show abstract

Section: Resultssupporting

confidence: 51%

In vitro assessment of Function Graded (FG) artificial Hip joint stem in terms of bone/cement stresses: 3D Finite Element (FE) study

Al-Jassir

Fouad

Alothman

2013

BioMedical Engineering OnLine

View full text Add to dashboard Cite

show abstract

“…The Cartesian coordinate system components x , y and z directions were along the body direction of medial to lateral, posterior to anterior and distal to proximal directions, respectively. The femur was fixed at the end (femoral end at the knee joint), and perfect bonding was considered between the bone and cement . Here, the interaction between the femoral prosthesis and cement was defined as surface‐to‐surface contact with a small sliding and friction coefficient of 0.3 …”

Section: Methodsmentioning

confidence: 99%

“…The femur was fixed at the end (femoral end at the knee joint), [22][23][24] and perfect bonding was considered between the bone and cement. 22,23,25 Here, the interaction between the femoral prosthesis and cement was defined as surface-to-surface contact with a small sliding and friction coefficient of 0.3. 20,22,23,25 Mesh property of implanted femur…”

Section: Boundary Conditions Of Implanted Femurmentioning

confidence: 99%

See 1 more Smart Citation

Internal–external circumferential crack behaviour in the cement layer of total hip replacement

Oshkour

Osman

Yau

et al. 2013

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

This study aimed to investigate crack behaviour at the internal and external surfaces of the cement layer in total hip replacement. A three‐dimensional model of the femur with the cemented prosthesis was developed and analysed. Cracks were placed on the internal, external and both internal and external surfaces of the cement layer. Stress intensity factors were measured during gait. Results revealed that the stress intensity factors modes I and III were the most dominant in the crack propagation in the cement layer. The domain of mode I was the medial and lateral sides of the cement layer. Meanwhile, the domain of mode III was the anterior and posterior sides of the cement layer. The stress intensity factor and distance from the distal end indicated an inverse relationship. The internal and external cracks had no significant interaction. Moreover, stress intensity factors at the external surface of the cement layer were higher than those on the internal surface.

show abstract

“…Such was the case described by Yang et al (37) where different implants were designed in order to find out the one that helps better improve medullary revascularization. It can help develop designs that can improve what is already in use, and, more importantly, can fabricate the designs for mechanical testing.…”

Section: Ebm Applicationsmentioning

confidence: 99%