Published online Nov 18, 2022. doi: 10.5312/wjo.v13.i11.1029
Peer-review started: May 6, 2022
First decision: August 1, 2022
Revised: August 16, 2022
Accepted: October 5, 2022
Article in press: October 5, 2022
Published online: November 18, 2022
Total knee arthroplasty (TKA) is a highly effective procedure for the treatment of end stage arthritis, and is the most common arthroplasty procedure performed worldwide. Although many patients report satisfaction with their outcomes, an estimated 10%–20% report being dissatisfied in the absence of clinical complications. This is significant given that in patients who have undergone total knee replacement, 25% or more will go on to have the contralateral side replaced in the future. Unlike unilateral TKA, there is very limited data on patient satisfaction following staged TKA, particularly comparing one side to the other.
Our motivation arose from the anecdotal experience that patients who have undergone bilateral knee replacement in a staged fashion indicate that the second side (TKA2) had a less satisfying outcome compared to the first side (TKA1). Our initial cursory reviews of the literature also seemed to confirm this experience. However, little is known about the factors associated with these reports. To better understand the phenomenon of unilateral dissatisfaction, the goal of this study was to perform a systematic review on currently available literature investigating patient reported outcomes and satisfaction following staged bilateral TKA.
The primary aim of this review article was to consolidate available published data revealing satisfaction scores among patients following staged bilateral TKA and to evaluate the phenomenon of less satisfying results following TKA2. Ideally, quantifying reported dissatisfaction as well as trending associated factors.
A systematic review of available literature reporting on satisfaction with TKA1 and TKA2 after staged bilateral knee arthroplasty was undertaken using PubMed, Google Scholar, and Embase. Among 427 records, five articles meeting inclusion criteria were included in the meta-analysis. Statistical analysis was performed to calculate relative risk of TKA2 dissatisfaction and compare the relative risk of TKA2 dissatisfaction between studies.
In the five included studies, a total of 1889 patients with an average age of 68 years underwent staged bilateral TKA with patient reported outcomes and satisfaction recorded at 1 year following each TKA. Average time between surgeries was 21.9 mo. Overall satisfaction with both knees was 83.70 % (1581), and dissatisfaction with both knees was 2.75% (52). In the remaining 13.56% (256) who were dissatisfied with one side, 61.0% were dissatisfied with TKA2, and 39.0% were dissatisfied with TKA1. Patient-reported outcome scores for TKA2 were frequently lower than TKA1 even in patients reporting overall satisfaction with both knees.
In patients undergoing staged bilateral TKA, we calculated a 50% increased risk of dissatisfaction with TKA2 compared to TKA1. Although we were unable to establish risk factors linked to this phenomenon, there is high suspicion that the factors are multifactorial and often patient specific.
Future directions include investigating the effects of time between surgeries and scheduled long-term follow-up.