Article
To resurface or not to resurface the patella in total knee arthroplasty
Search Medline for
Authors
-
N. Helmy
- Universität Zürich, Uniklinik Balgrist, Zürich, Switzerland
-
N. Greidanus
- University of British Columbia, Vancouver General Hospital, Vancouver, Canada
-
B. Masri
- University of British Columbia, Vancouver General Hospital, Vancouver, Canada
-
C. Anglin
- University of Calgary, Centre for Bioengineering Research & Education, Calgary, Alberta, Canada
| Published: | October 16, 2008 |
|---|
Outline
Text
Background: The management of the patellar articular surface at the time of primary total knee arthroplasty is controversial. The purpose of this study was to determine the optimal management strategy (resurfacing versus non-resurfacing), with the use of expected-value decision analysis.
Methods: Outcome probabilities and utility values were determined using data from randomized controlled trials only. A decision tree was constructed and fold-back analysis was performed to evaluate for the optimal path of treatment. Sensitivity analyses were performed to determine the effect on decision-making of varying outcome probabilities and utilities.
Results: Our model showed that patellar resurfacing is the optimal management strategy for the patella at the time of primary TKA. This decision is robust to changes in the specific data, as the optimal path would remain the same as long as the incidence of persistent anterior knee pain with resurfacing remains 29% (current mean, 12%). Delayed (i.e. secondary) patellar resurfacing for ongoing patellar pain provides inferior results for the majority of patients. Of the patients who did not receive patellar resurfacing at the index procedure and who underwent secondary resurfacing due to anterior knee pain, 39% experienced an improvement in their expected health utility from 0.52 to 0.59. However, for the remaining 61%, persistent pain coupled with the second operation resulted in a drop in the expected utility to 0.42.
Conclusions: In this decision analysis the optimal management path for the majority of patients is to resurface the patella at the time of the index arthroplasty procedure. Sensitivity analyses demonstrated that only in unusual clinical circumstances would non-resurfacing be associated with a superior outcome. Secondary resurfacing is not advocated, since the benefit experienced by some patients following late resurfacing does not offset the disutility experienced by all patients undergoing the second operation.
Level of Evidence: Decision analysis - Level I
