Failure analysis of the cement mantle in total hip arthroplasty with an efficient probabilistic method

Abstract

Accurate prediction of long-term behaviour of cemented hip implants is very important not only for patient comfort but also for elimination of any revision operation due to failure of implants. Therefore, a more realistic computer model was generated and then used for both deterministic and probabilistic analyses of the hip implant in this study. The deterministic failure analysis was carried out for the most common failure states of the cement mantle. On the other hand, most of the design parameters of the cemented hip are inherently uncertain quantities. Therefore, the probabilistic failure analysis was also carried out considering the fatigue failure of the cement mantle since it is the most critical failure state. However, the probabilistic analysis generally requires large amount of time; thus, a response surface method proposed in this study was used to reduce the computation time for the analysis of the cemented hip implant. The results demonstrate that using an efficient probabilistic approach can significantly reduce the computation time for the failure probability of the cement from several hours to minutes. The results also show that even the deterministic failure analyses do not indicate any failure of the cement mantle with high safety factors, the probabilistic analysis predicts the failure probability of the cement mantle as 8%, which must be considered during the evaluation of the success of the cemented hip implants.

Patient-Specific Static Structural Analysis of Femur Bone of different lengths

“…A mesh dependency study was accomplished to determine the appropriate mesh size for the unstructured mesh developed. The mesh size was gradually reduced from 10 to 1 mm in accordance with an earlier study [21]. The variation of the stress developed for change in mesh size is graphically shown in Fig.…”

“…Bone is a rigid structure with harder at outer surface known as cortical bone and soft at inner surface known as cancellous bone. In the analysis, the bone was considered as the isotropic and static analysis was carried out to evaluate the stresses induced in the bone during different activities [21]. In this work, the CT scan images of 2 patients were modelled three dimensionally as complete solid femurs (tall femur and short femur) without considering separate properties for cortical, cancellous bone [27].…”

Prediction of the probability of revision hip arthroplasty with replacement of the acetabular component depending on the type of its cement fixation

“…No recommendations were given on tactics in cases of anticipating an adverse outcome [21]. I. Kaymaz et al emphasize the need for more time duration for calculating the numerical parameters of the prediction [22].…”

Biomechanics of hip joint: a systematic review

“…Many researchers studied the forces acting on the hip joint by using computational methods [57]. They used the CT scans of the bone to model the femur bone [58]. The 3D model is subjected to different types of forces which are acting on the hip joint and also normal gait cycles are used.…”

“…Von Mises stress at the UHMWPE cup decreases by increasing the femur head diameter for all types of femur head materials [58] Calculation of contact stresses on cartilage with test subject-specific DEA, comparison with FEA Higher contact stresses with DEA than with FEA (9.8-13.6 MPa vs. 6.2-9.8 MPa maximum stresses), faster computing times with DEA (7sec. vs. 65 min.…”