Aim: The most important long-term complication in total joint replacements is aseptic osteolysis. Our aim was to use immunohistological methods to study samples taken during total hip arthroplasty revision surgery. And to compare these results with the preoperative radiological findings.

Methods: Between 1996 and 2003, 103 revision of total hip arthroplasty have been performed because of aseptic loosening at our Department. Out of these 103 cases 83 histological examination was performed. The samples taken during surgery are stored in paraffin-embedded tissue sections at the University’s Department of Pathology. Aseptic loosening of prosthetic components after total hip replacement is characterized by the formation of a synovial membrane-like tissue. Particle induced osteolysis is a primary cause of aseptic loosening through cytokine production in response to phagocytosis of implant wear particle. To study the local immun (macrophage) reaction, we applied labelling of sections by immunohistochemistry using the macrophage marker anti-CD68, anti-TNF-α marker and Crosmon staining. Osteolysis on the AP and lateral radiographs was detected by the periprosthetic radiolucent zones. Classification was performed by the Paprosky and DeLee-Charnley methods. The results of the radiological analysis was compered statisticaly to the immunohistological findings.

Results: Increased macrophage activity showed an elevation in the immun-markers in the samples. In the radiologicaly more severe cases an increase in the immun response was detected.

Purpose: The purpose of this research was to evaluate the degree of polyethylene wear in the acetabular component 10 years after cemented total hip arthroplasty. In addition, with the help of the accepted standards the connection between the degree of acetabular wear and acetabular loosening was studied. Materials/Methods: 110 cases, operated with cemented arthroplasty of the hip in 1990–1992, were selected for the study. Antero-posterior (AP) and lateral radiographs were analyzed with regard to migration, radiolucent lines, pelvic osteolysis and two-dimensional linear wear of the polyethylene. The diameter of the component was measured (diameter of the wire markers imbeded in the plastic), and the distance between the central point of the femoral head component and the outer ring (T1 and T2). The ratio calculated from these distances (T1/T2) presents the linear scale of the component wear and the migration of the femoral head component. The polyethylene wear was further studied in contrast of the femoral head component size (26 and 32). In addition, the degree of acetabular loosening was measured by the De Lee and Charnley radiological score. Results: Out of the 110 cases, 23.1% of the T1/T2 ratio equaled 1, measured on the AP roentgenographs, which means that there is no wear in the acetabular component. 30.5% of the cases had a ratio of 0.96–1 (minimal wear), 30.5% of the cases had a ratio of 0.92–0.96 (intermediate wear). Severe wear (less than 0.92) was observed in 15.9% of the cases. These same ratio groups on the lateral view had the following distribution in respected order: 27.3%, 33.4%, 28.7%, 10.6%. Polyethylene wearing was found to be more evident when a 26 size femoral head was used. Advanced acetabular loosening in the radiological findings was only evident in the most deteriorated group. Conclusion: It can be concluded that the degree of the polyethylene wear of the acetabular component can be satisfactorily measured from the migration of the femoral head component on the roentgenographs. The dissimilar distribution of the ratio groups between the AP and lateral roentgenographs indicate asymmetrical wear.

The aim of the study was to determine the mid-term clinical result of the patient operated by Chiari pelvic osteotomy.

A mid-term evaluation of the Chiari pelvic osteotomy performed on 65 hips in 58 patients is presented. Indications were: 1) congenital hip dysplasia in cases where conservative or other surgical treatment had failed, 2) deformed, laterally uncovered femoral head due to Legg-Calvé-Perthes disease, 3) age between 10–40 years, 4) no signs of advanced osteoarthritis.

Patients were classified according to pain, limp, Trendelenburg sign, range of motion, abductor muscle strength, and radiographic appearance (Wiberg and Idelberger angles). A mean follow-up of five years revealed relief of pain and an increase of hip motion in many cases. However, limping and a positive Trendelenburg sign frequently persisted. The radiographic appearance showed that the Wiberg angle had increased from the preoperative average of 6 degrees to 30 degrees postoperatively. The Idelberger angle decreased from the preoperative average of 72 degrees to an average of 60 degrees postoperatively.

The Chiari osteotomy is a technically exacting procedure which provides adequate femoral head coverage. This coverage facilitates pain relief and increased function. However, the results were less consistent in the cases of Perthes disease.

Considering the indications and contra-indications, the Chiari pelvic osteotomy has good clinical results in the reduction of painful standing and walking of young adult patients with DDH.