ILIOPSOAS IMPINGEMENT AFTER TOTAL HIP ARTHROPLASTY - FINITE ELEMENT ANALYSIS

Aim of this paper. Is to study the iliopsoas impingement with threedimensional modeling (3D) after total hip arthroplasty in extended position of the hip in case of 28 and 36 mm diameter prosthetic heads and the acetabular component in malposition (retroversion). Material and methods. We performed a 3D reconstruction of the pelvic bone, the left femur and left iliopsoas muscle of a 27 year old male based on CT images. After that we created a solid body that we used for the arthroplasty performed in the variants mentioned above and we used the finite element method for the analyses. Results. There were no traces of impingement with the 28 mm and 36 mm diameter femoral head, when the joint is in extension. When the acetabular component was in malposition, we found a stress aerie on the iliopsoas muscle and acetabular component meeting point. Conclusion. In our research, we demonstrated by 3D modeling and finite element analysis that after total hip arthroplasty using a large diameter femoral head, with the hip in extension, there is no pressure on the surface of iliopsoas muscle, contrary with the case of the acetabular component in retroversion. We can avoid this placing the acetabular component in angle of 45o inclination and 10o anteversion

ILIOPSOAS IMPINGEMENT AFTER TOTAL HIP ARTHROPLASTY - FINITE ELEMENT ANALYSIS

Aim of this paper. Is to study the iliopsoas impingement with threedimensional modeling (3D) after total hip arthroplasty in extended position of the hip in case of 28 and 36 mm diameter prosthetic heads and the acetabular component in malposition (retroversion). Material and methods. We performed a 3D reconstruction of the pelvic bone, the left femur and left iliopsoas muscle of a 27 year old male based on CT images. After that we created a solid body that we used for the arthroplasty performed in the variants mentioned above and we used the finite element method for the analyses. Results. There were no traces of impingement with the 28 mm and 36 mm diameter femoral head, when the joint is in extension. When the acetabular component was in malposition, we found a stress aerie on the iliopsoas muscle and acetabular component meeting point. Conclusion. In our research, we demonstrated by 3D modeling and finite element analysis that after total hip arthroplasty using a large diameter femoral head, with the hip in extension, there is no pressure on the surface of iliopsoas muscle, contrary with the case of the acetabular component in retroversion. We can avoid this placing the acetabular component in angle of 45o inclination and 10o anteversion

IMPROVING QUALITY OF LIFE AFTER HIP REVISION ARTHROPLASTY

Nowadays the number of primary arthroplasties is growing and revision arthroplasty is becoming increasingly necessary. In this study we intend to examine the effectiveness of arthroplasties and assess the quality of life. We included 35 patients with revision arthroplasty and 35 primary hip arthroplasty patients who had surgery between 2011 and 2012 in the study. To examine the results we used the modified Harris hip score and the Rosser matrix, which was completed before surgery and 2-3 years after the procedure. We observed a statistically significant improvement: from 34 preoperative Harris hip score 75 at the 2 years postsurgery assessment and 72 at the 3 years postoperative assessment (p <0.0001). Significant improvements were also registered when assessing the health state with the Rosser matrix. The effect for the Harris score had a value of 2.06 which testifies the revision surgery has a high effectiveness. This means that with this kind of procedures dramatic improvement in quality of life can be achieved

CERAMIC-ON-CERAMIC TOTAL HIP ARTHROPLASTY IN YOUNG PATIENTS WITH FEMORAL-HEAD OSTEONECROSIS - SHORTTERM RESULTS

Aim: the increasing number of total hip arthroplasties in case of young, physically active patients means an increasing number of revision surgeries as well. For these patients the use of ceramic bearings could be an appropriate solution because of its reduced wear and a predicted longer lifetime. In this paper we would like to present our short experiences with non-cemented, ceramic-on-ceramic total hip prosthesis, in case of young patients. Materials and Methods: between January 2011 and December 2012, 32 hip arthroplasties were performed in case of 31 young patients diagnosed with avascular necrosis of the femoral head. The clinical and radiological follow-up of these patients was carried out for an average of 1,5 year. The average age was 47 years (25-51) in the moment of the surgery. The clinical assessment of the patients were carried out by the Harris Hip Score and Visual Analog Scale, performed before and 3, 6, 12 month after surgery. The radiological evaluation was based on the anteroposterior and axial radiographs performed at the above mentioned time points. Results: in each cases the bony ingrowth of the prosthesis took place. No stressshielding phenomenon was observed at the proximal part of the femur. In one case at six month control X-ray we noticed the damage of the ceramic insert and no further complications were observed. The patient refused the revision surgery for now. Conclusions: the fourth-generation ceramic component for non-cemented endoprosthesis used in case of young patients has very good early clinical and radiological results