ABSTRACT
PURPOSE: To suggest operative methods for revision total knee arthroplasty (TKA) according to the causes of revision surgery. MATERIALS AND METHODS: The operative methods of 70 revision total knee arthroplasties in 64 patients between December 1996 and December 2004 were analyzed according to the causes. The mean follow-up period was 65 months (25-120 months). The range of motion and Hospital for Special Surgery (HSS) score were used for the clinical evaluation and the scoring system of American Knee Society was used for the radiographic evaluation. RESULTS: The mean periods of revision surgery from the initial operation was 59 months (1 month-20 years). Posterior cruciate retaining prosthesis was used in 8 cases, posterior cruciate substituting prosthesis in 14 cases, and constrained type prosthesis in 48 cases. The extension stem was required in 51 cases, metal augmentation in 34 cases, and structural allograft in 15 cases for bone defect treatment and firm fixation. The average range of motion improved from 88.8o preoperatively to 105.8o at the final follow-up. HSS score also improved from 60.5 to 87.6 points. The complications after revision TKA were 3 infections (4.3%), 1 patellar dislocation (1.4%), and 1 polyethylene dislocation (1.4%). CONCLUSION: Constrained type prostheses were needed in many cases of revision TKA. Satisfactory results were obtained using an additional structural allograft, metal augmentation, and extension stem for bone defect treatment and firm fixation.
Subject(s)
Humans , Allografts , Arthroplasty , Joint Dislocations , Follow-Up Studies , Knee , Methods , Patellar Dislocation , Polyethylene , Prostheses and Implants , Range of Motion, ArticularABSTRACT
PURPOSE: To determine the effect of lateral retinacular release on patellofemoral alignment in primary total knee arthroplasty (TKA). MATERIALS AND METHODS: From June 1990 to December 1998, 351 cases of TKA, which were followed up more than 3 years, were divided into two groups, 147 cases (group I) with lateral retinacular release and 204 cases (group II) were without release. We compared the two groups in terms of the range of motion, patellofemoral alignment and clinical results using a Hospital for Special Surgery score. RESULTS: Average range of motion in group I (112 degrees preoperatively and 113 degrees on final follow-up) and group II (114 degrees preoperatively and 113 degrees on final follow-up) showed no statistical difference. The average functional knee score in group I (58 preoperatively and 88 on final follow-up) and group II (59 and 85 respectively) also showed no statistical difference. Patellar maltracking occurred in 4 cases (2.7%) in group I and 31 cases (15.2%) in group II. Patellar tilting (4.5 degrees in group I and 7.7 degrees in group II) and patellar translation (3.7 mm in group I and 7.8 mm in group II) showed significant statistical difference between the two groups at the final follow-up. CONCLUSION: Patellar tracking was better in the lateral retinacular release group, although there was no clinically significant difference at the short term follow-up period.