Patellar Nonresurfacing in Total Knee Arthroplasty

PURPOSE: The management of the patella in total knee arthroplasty is still controversy. The purpose of this study was to evaluate clinical and radiological results after total knee arthroplasty without patellar resurfacing. MATERIALS AND METHODS: We retrospective evaluated the nonresurfaced patella in 50 Knees(45 patients) at an average of 65.5 months after total knee arthroplasty(Duracon (R), Howmedica, Rutherford, NJ). Patients were diagnosed as osteoarthritis in 45 and rheumatoid arthritis in 3 and the others were osteonecrosis and evaluated using the knee society knee score, functional knee score and modified patellar score. RESULTS: The mean preoperative knee society knee score in osteoarthritis and rheumatoid arthritis were 58.2 and 36.7 points, and functional score were 35.8 and 34 points. The mean postoperative knee society knee score in osteoarthritis and rheumatoid arthritis were 94.5 and 91.2 points, and functional score were 73.2 and 81 points and the mean modified patellar score was 28.5 points, and 26 cases(52%) were excellent(30-35 points), 18 cases(36%) were good(25-29 points) and 6 cases(12%) were fair(20-24 points). There were no patella-associated complications and in 8 cases(16%) of anterior knee pain, which resolved by a postoperative 4.1 months with conservative treatment. CONCLUSION: Total knee arthroplasty with patelloplasty, without patellar resurfacing , provided satisfactory results without significant problems, and can avoid the patellar complications. But long term radiological and clinical follow-up is recommended.

Total Knee Arthroplasty without patellar resurfacing

Patello-femoral problem is one of the common complications in total knee arthroplasty and whether to replace the patella or retain it has long been controversial in order to prevent the complications. 43 cases (35 patients) of total knee arthroplasty with patellar retention performed by a single surgeon between August 1993 and August 2000 were reviewed retrospectively. The follow-up period averaged 54 months (range, 24-120 months). The whole cases were divided into three groups according to the preoperative radiographs. Group A was normal patella (10 knees), Group B was borderline arthritic patella (20 knees), and Group C was severely deformed patella (13 knees). All of 43 knees, regardless of preoperative radiological degree of arthritis received patelloplasty including removal of osteophytes, subchondral shaving and lateral retinacular release was performed in 20 knees (47%). Each groups was evaluated in terms of the objective criteria of anterior knee pain, range of motion, stair climbing ability, and roentgenographic findings. All 35 patients were diagnosed as osteoarthritis in 29 and rheumatoid arthritis in 6. American Knee Society Score (KSS) was assessed for the clinical analysis and lateral patella shift and patella tilt were assessed for roentgenographic analysis. The mean Knee Society Score at final follow-up was 94 in group A, 93 in group B, and 94 in group C. Mild anterior knee pain was reported in 9.3% (Group A: 2 cases, Group C: 2 cases). patellar tilt was significantly higher in C group (oneway ANOVA test, p=0.01), representing that advanced patello-femoral arthritis caused increased patellar tilt. There was neither significant difference in terms of range of motion, and stair climbing ability nor of patellar shift among all three groups. TKA with patelloplasty, not resurfacing the patella, provided satisfactory results without significant problems regardless of the preoperative degree of patello-femoral arthritis.