Primary Cementless Total Hip Arthroplasty with a Ceramic Sandwich Liner and a Third Zweymuller Stem: Minimum 8-Year Follow up Results / 대한고관절학회지

PURPOSE: The purpose of this study is to evaluate the minimum eight-year follow up results of primary total hip arthroplasty (THA) performed using an alumina sandwich liner and the third Zweymuller stem. MATERIALS AND METHODS: A total of 86 patients (107 hips) who underwent a THA with alumina sandwich liners and the third Zweymuller stems from July 2001 to December 2003 were analyzed. Mean age of patients at the time of THA was 50.8 years (range, 17-77 years) and the mean follow-up period was 112 months (range, 98-127 months). Clinical evaluation was performed using the Harris hip score and level of thigh pain. The radiographic evaluation was performed in terms of the radiolucent line, subsidence of the stem, migration of the acetabular cup, and proof of loosening. RESULTS: At the final follow-up, mean Harris hip score had improved from 57.8 points to 91.9 points. Radiolucent line was observed at Gruen zone 1 in 40 cases (37%) and at zone 7 in 35 cases (33%); however, no detectable loosening was observed. There were six cases (5.6%) of fracture of the ceramic liner, one case of ceramic liner dissociation, and one case of stem loosening due to infection. CONCLUSION: At the minimum eight-year follow up, survival rate of the third Zweymuller stem was 99.1%. However, owing to the high rate of fractures of the ceramic sandwich liners, the survival rate of the ceramic liner was 93.5%.

Relationship between Tibial Bone Defect and Extent of Medial Release in Total Knee Arthroplasty

PURPOSE: To understand the relationship between tibial bone defect and extent of medial release in total knee arthroplasty. MATERIALS AND METHODS: We evaluated 32 knees in 22 patients with variable degrees of tibial bone defect on medial plateau has undergone total knee arthroplasty. In this study, 31 cases had been diagnosed as degenerative osteoarthritis and 1 case was osteonecrosis. We excluded cases with infection, traumatic arthritis, or neuropathic joints. With regard to gender, 29 cases were female and 3 cases were male. The following relationships were analyzed: preoperative degrees of tibial bone defect and varus deformity; the femorotibial angle of both weight-bearing whole extremity radiogram, distractive stress radiogram, and the extent of medial release. RESULTS: Average tibial bone defect was 9.8+/-4.1 mm. Average femorotibial angle on weight-bearing whole extremity radiograph was varus 10.0degrees+/-6.2degrees. Average femorotibial angle on distractive stress radiograph was varus 0.7degrees+/-4.6degrees. Statistically the extent of medial release showed no significant relationship with the degree of tibial bone defect and femoro-tibial angle of whole extremity radiogram. However, it revealed a statistically significant relationship with the femorotibial angle on distractive radiogram (r=0.465, p=0.007). CONCLUSIONS: Preoperative distractive stress radiograph might be a useful method to predict the extent of intraoperative medial release during total knee arthroplasty.