The Management of Bone Defects in Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: Bone defects in revision TKA were classified according to AORI (Anderson Orthopedic Research Institute) system and results of the treatment are reported according to this classification. MATERIALS AND METHODS: The results of 24 revision TKAs operated from Mar. 1991 to Apr. 1999 were analysed. Fourteen knees had type 1 tibial defects, four knees had type 2 and six knees had type 3. On the femoral side, twelve knees had type 1, four knees had type 2 and seven knees had type 3 defects. Cement and chip bone grafts were mainly used to fill bone defects in type 1, wedges or blocks in type 2 and structural allograft combined with the other methods in type 3. Results were evaluated using the knee and functional scores of the American knee society. RESULTS: The analysis of the results according to the method of treatment- cement filling, chip bone graft, structural bone graft, wedge or blocks and custom made prosthesis- revealed improvements of knee scores in all groups except for custom made prosthesis. CONCLUSION: Satisfactory clinical results were obtained for the management of bone defects according to the AORI classification system in revision total knee arthroplasty.

Fixation Strength Analysis of Press-Fit Technique in Anterior Cruciate Ligament Reconstruction using Porcine Lower Limb / 대한정형외과연구학회지

PURPOSE: The objective of this study was to evaluate the initial fixation strength of press-fit technique compared with titanium and biodegradable interference screws in ACL reconstruction using bone-patellar tendon-bone grafts. MATERIALS AND METHODS: Fifty porcine lower limbs were used. The graft in the press-fit group was harvested with a hollow oscillating saw to obtain a consistent and complete circular shape and that in the interference screw group was obtained with a conventional oscillating saw. With preload of 20 N, the specimens underwent 250 loading cycles between 0-2 mm of displacement. Thereafter, the specimens were loaded to failure after restoration of the preload. RESULTS: During the cyclic loading, none of press-fit or interference screw fixations failed and there was no significant difference in maximum loads between the groups. In groups of press-fit fixation with diameter of bone plug being larger that that of the femoral tunnel by 1.4 mm, the ultimate failure load was comparable with that of the titanium or biodegradable interference screw groups. The complete circular shape and increased diameter of the bone plug seemed to contribute the strong initial fixation. CONCOUSION: Press-fit fixation technique provides a secure and consistent fixation strength comparable with the metal or biodegradable interference screws.

Arthroscopic Treatment of Degenerative Arthritis of the Knee

PURPOSE: To evaluate the efficacy and the prognostic factors in arthroscopic treatment of degenerative arthritis of the knees MATERIALS AND METHODS: The results of 115 knees in 110 patients had been treated arthroscopically from Jan. 1990 to June 1999 were analysed. Mean age was 56 years old and mean follow-up period was 1 years 9 months(range: 1 year-7 year). Pain, Range of motion, Lysholm score, and changes of subjective symptoms were assessed for clinical evaluation, Preoperative and postoperative X-rays of the knees and arthroscopic findings were also reviewed and statistical analysis was performed. We tried to find out the clinical results and prognostic factars in arthroscopic treatment of the degenerative arthritis. RESULTS: The best clinical improvement was observed in postoperative 1-2 year period and the clinical improvement was continued by 3 years after surgery. Sixty two percents of patients had significant improvement of subjective symptoms for 1-2 year postoperatively, and 52% for at least 3 years after surgery. The patients of younger age, normal weight, normal alignment of lower leg(1 degrees - 7 degrees degree of tibio-femoral angle) and shorter duration of preoperative symptoms showed better clinical results. Eighty percents of improvement of subjective symptoms has been obseved in the group of patient who had the mechanical symptoms preoperatively. In the knee with mild cartilage degeneration(according to Jack-sons classification, stage I or II) and with torn meniscus showed better clinical improvement after surgery compared with those of severe cartilage degeneration or intact menisci. CONCLUSION: Arthroscopic treatment can be considered as a succesful treatment method for temperary relief of symptoms in the degenerative arthritis of knees. However, careful selection of patients looks mandatory for favorable results. The favorable prognostic factors in the study were younger age, no obesity, shorter duration of symptoms, nearly normal alignment of knees, less cartilage degeneration, mechanical symptoms, and torn meniscus.

Treatment of Patellar Fracture by percutaneous tension band wiring and open tension band wiring techniques

PURPOSE: By comparing the results of the percutaneous tension band wiring with those of the open tension band wiring for the treatment of patellar fracture, we tried to sh6w the practical use of the percutaneous tension band wiring. MATERIALS AND METHODS: We analyzed radiological and clinical results of 10 cases of isolated patellar fractures treated with the percutaneous tension band wiring and 10 cases of isolated patellar fractures treated with the open tensian band wiring. RESULTS: There were no significant differences between the percutaneous tension band wiring and open tension band wiring on operation time, knee score and function score, but the percutaneous tension band wiring showed more rapid on bony union. Two cases treated with the open tension band wiring showed limitation of motion of the knee joint, and one case treated with the open tension band wiring showed patellar elongation. CONCLUSION: Comparing with the open tension band wiring, the percutaneous tension band wiring can be done without wide skin incision and can give patients more satisfaction. We concluded that the percu-taneus tension band wiring is a good method and can replace the conventional open tension band wiring.

Clinical and Radiological Results of Total Knee Arthroplasty with a System of Asymmetric Tibial Tray

PURPOSE: PURPOSE of this study was to evaluate the clinical and radiological results and complications of total knee arthroplasty(TKA) using the systems including an asymmetric tibial tray and a deep trochlear-grooved femoral component. MATERIALS AND METHODS: Ninety-five total knee replacement arthroplasties(68 patients) with the implant system, which has the asymmetric tibial tray and a deep trochlear grooved femoral component were analyzed clinically and radiologically. Retrograde analysis with the Knee Society clinical rating system, roentgenographic evaluation and scoring system and the Hospital for Special Surgery(HSS) score were done. The patients were average 66 years old and the follow-up period was 23month(range, 12 month to 49 month). RESULTS: Knee score was improved from 43 points to 90 points. Function score was improved from 47 points to 85 points. HSS score was improved 57 points to 89 points. Tibio-femoral angle was improved from varus 4o to valgus 5o. In last clinic visit, there was no case which had progressive radiolucent line or above 4 points in radiolucent score except one septic loosening case. There was no case of patellofemoral complications, including patellofemoral instability, patellar fracture, patellar component failure, patellar component loosening, and patellar clunk syndrome. CONCLUSTION: The TKA in this series showed excellent clinical and radiological results and low inci- dence of patellar complication.

Periprosthetic Fractures After Total Knee Arthroplasty

PURPOSE: To analyse of the result of the treatment of periprosthetic fractures after total knee arthroplasty. MATERIALS AND METHODS: We reviewed 1J knees of 11 patients with supracondylar periprosthetic fractures who underwent total knee arthroplasty between July 1989 and October 1998. There are 1 man and 10 women. The average follow-up period was 24 months(Range, 6 - 61). The patients were grouped according to the treatment mothods; Group I is the patients who were treated by cast or cast brace. Group II is the patients who were treated by skeletal traction followed by cast or cast brace. Group III is the patients who were treated by retrograde intramedullary nails, We analysed time required for union, tibiofemoral angle after union, Range of motion and HSS score of each group. RESULTS: Time required for union is shorter in Group I and III than Group II. Tibiofemoral angle after union is not significant change in all Groups postoperatively. ROM was not decreased in Group III but there was significant changes. HSS score was decreased in Group II, 85 preoperatively and 64 postopera-tively. CONCLUSION: Cast or Cast brace only can be recommended for knees in which the initial alignment and stability of fracture were in acceptab1e range, In knees with malaligned and unstable periprosthetic fracture, retrograde IM nails can be recommended for better clinical and radiological results.