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Background: The aims of the present study are to (1) conduct the longest-to-date follow-up wear analysis of the highly cross-linked polyethylene acetabular liners, (2) assess the incidence of femoral and acetabular osteolysis, and (3) compare the surgical outcomes between standard and elevated-rim acetabular liners in primary total hip arthroplasty (THA).Methods: In this retrospective cohort study, we evaluated 112 primary THAs performed by a single experienced arthroplasty surgeon at our institution between March 2000 and December 2003. Patients were classified based on the type of acetabular liner used: standard or elevated-rim liner. For evaluation of surgical outcomes, the following data were collected: acetabular cup position (anteversion and inclination), wear rate (linear and volumetric), presence of osteolysis, history of reoperation (all-cause and wear-related), complications (deep joint infection, dislocation, and periprosthetic fracture), and Harris hip score at last follow-up.Results: Linear and volumetric wear rates were 0.028 mm/y (0.000-0.145 mm/y) and 11.641 mm3/y (0.000-70.000 mm3/y) in the standard group and 0.026 mm/y (0.000-0.094mm/y) and 9.706 mm3/y (0.000-33.000 mm3/y) in the elevated-rim group, respectively. These rates were not significantly different between groups. One case of osteolysis was confirmed in the standard group, whereas no osteolysis was observed in the elevated-rim group.Conclusion: We suggest that elevated-rim highly cross-linked polyethylene acetabular liners might be a good implant option that can be used safely. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the influence of the posterior approach with soft tissue repair in revision hip arthroplasty by evaluating the rate of early posterior dislocation. Ninety-one patients (96 hips) who had undergone revision hip arthroplasty through the posterior approach were observed for 1 year or until dislocation occurred. Fifty-six revision hip arthroplasties were performed using the posterior approach with soft tissue repair technique. The results of these procedures were compared with those of 40 revision hip arthroplasties that had been performed using the posterior approach without soft tissue repair. The dislocation rate of 10.0% in 40 hips using the posterior approach without soft tissue repair was reduced to 1.9% in 56 hips using the posterior approach with soft tissue repair. [Copyright &y& Elsevier]

Abstract: We report an unusual case of a chronic prosthetic dislocation that was caused by the buttonholing of a prosthetic femoral head by anterior soft tissue, which impeded reduction. A surprisingly good functional result was achieved by an open reduction and revision operation on a 56-year-old man, who had a chronic dislocation of a total hip prosthesis. Successful treatment with open reduction of a chronic proximal dislocation after total hip arthroplasty has not been reported previously in the literature. [Copyright &y& Elsevier]

Abstract: This study investigated a reference line that is closer to the true femoral anteversion on only the cutting surface of the proximal femoral neck during a femoral stem insertion in a cementless total hip arthroplasty. A postoperative computed tomography of both hips from 33 consecutive patients after a unilateral primary cementless total hip arthroplasty with an avascular necrosis of the femoral head was taken to observe the positioning of the stem and its correlation with the true anteversion of the contralateral side. The average of the midcortical angle was 14.1° ± 6.8° on the lesion side and 0.1° ± 1.3° more than the true anteversion on the contralateral side. This study has shown that anteversion using a midcortical line between the anterior cortical line and the posterior cortical line is compatible with the true femoral anteversion. However, further investigation is required to confirm the true femoral anteversion. [Copyright &y& Elsevier]

Abstract: A pathological fracture of the right femoral neck associated with osteonecrosis of the right femoral head and a stress fracture of the contralateral femoral neck occurred in a 47-year-old man. Osteonecrosis was noted in almost the entire femoral head, and the pathological fracture occurred at the subcapital area. Six months later, a stress fracture was detected in the contralateral femoral neck. The stress fracture of the left femoral neck might have been caused by the incremental repetitive mechanical loading in the left hip as a result of the pathological fracture in the right hip. Therefore, it might be necessary to conduct a careful examination, using either a magnetic resonance imaging scan or a bone scan, of patients with extensive osteonecrosis of the femoral head because of the risk of osteonecrosis in the contralateral femoral head as well stress fractures in the contralateral femoral neck. [Copyright &y& Elsevier]