Results of Total Knee Arthroplasty with NexGen(R) system (5-year follow up) / 대한정형외과학회잡지

PURPOSE: To evaluate the mid-term (over 5 years) clinical and radiologic results of NexGen(R) total knee replacement arthroplasty (TKRA)retrospectively. MATERIALS AND METHODS: Between Nov. 1996 and Jun. 1997, 57 knees in 43 patients who had been followed up for 5 years after TKRA with NexGen(R) were evaluated retrospectively for clinical and radiologic results. RESULTS: The average range of motion increased from 116degree preoperatively to 125 degrees at the last follow-up. In patients with osteoarthritis, the average preoperative knee score (59.9) and functional score (40.3) improved to 94.7 and 83.7, respectively. In rheumatoid arthritis patients, the mean knee score and functional score also improved from 55.6 and 35.9 to 88.9 and 79.9. Roentgenographic evaluation revealed a radiolucency rate of 60%. Complications were periprosthetic fractures in 2 cases and aseptic loosening in 1 case. The latter had received a reimplantation. CONCLUSION: The mid-term results of NexGen. TKRA were reliable and satisfactory in terms of improvements of; range of motion, restoration of function, and rare complications. However, long-term follow-up evaluation is necessary to monitor many cases of radiolucent line (60%) in the femoral component.

Screw and Cement Fixation of Tibial Bone Defects in Total Knee Replacement

PURPOSE: To evaluate clinical and radiographic results for screw and cement fixation of tibial bone defect in total knee replacement arthroplasty(TKRA) retrospectively. MATERIALS AND METHODS: From march 1995 to May 1998, 23 total knee replacement arthroplasties were performed in 19 adults with screw and cement fixation for tibial bone defect. They were followed retrospectively for at least 12 months at mean 28 months(12~50). The average age of the patients at the time of operation was 64 years. The American Knee Society clinical rating system was used for the assessment of the results. We also used Knee Society roentgenographic evaluation and scoring system in all cases for assessment of radiolu-cent line between bone and cement interface, prothesis and cement, and around the threads of the screw within the bone. RESULTS: The average 37.6 preoperative knee rating score and 41 functional score were improved to 94.9 and 95 retrospectively at the last follow-up. Roentgenographic evalua- tion revealed that no radiolu-cent line was detected between prothesis and cement, around the threads of the screws within the bone. Between bone and cement interface, we observed radiolucent line in 8 of 23 cases(34.8%) and they had no progression during follow-up. CONCLUSIONS: Screw and cement fixation may be tried when tibial bone defect are small and situated peripherally. But, we considered that more long-term follow-up evaluation must be needed.