Retrospective Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Mar 18, 2016; 7(3): 195-201
Published online Mar 18, 2016. doi: 10.5312/wjo.v7.i3.195
Knee awareness and functionality after simultaneous bilateral vs unilateral total knee arthroplasty
Roshan Latifi, Morten Grove Thomsen, Thomas Kallemose, Henrik Husted, Anders Troelsen
Roshan Latifi, Morten Grove Thomsen, Thomas Kallemose, Henrik Husted, Anders Troelsen, Department of Orthopedic Surgery, Copenhagen University Hospital Hvidovre, DK-2650 Hvidovre, Copenhagen, Denmark
Thomas Kallemose, Clinical Research Center, Copenhagen University Hospital Hvidovre, DK-2650 Hvidovre, Copenhagen, Denmark
Author contributions: Latifi R performed the initial drafting of manuscript; Latifi R and Thomsen MG collected the data; Latifi R, Thomsen MG, Kallemose T, Husted H and Troelsen A performed the data analysis, interpretation, the revision and final approval of manuscript; Thomsen MG, Husted H and Troelsen A designed the study.
Institutional review board statement: According to the national laws, questionnaire surveys and retrospective studies are exempt from obtaining approval from the National Research Ethics Committee (equivalent to IRB) (see Committee Acts at http://www.dnvk.dk/).
Informed consent statement: According to the national laws, it is not required to obtain informed written consent prior to conducting questionnaire surveys. Subjects were sufficiently anonymized and cannot be identified. Data were handled according to the acts of the Danish National Data Protection Agency. The Danish National Data Protection Agency approved this study (AHH-2014-010).
Conflict-of-interest statement: There are no conflicts of interest related to the present study.
Data sharing statement: The technical appendix, statistical code, and dataset associated with the present study are available from the corresponding author at roshan_latifi@yahoo.com. The data used in this study were sufficiently anonymized, and the Danish National Data Protection Agency approved this study (AHH-2014-010).
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Roshan Latifi, MD, Orthopedic Surgery Registrar, Department of Orthopedic Surgery, Copenhagen University Hospital Hvidovre, Kettegaard Alle 30, DK-2650 Hvidovre, Copenhagen, Denmark. roshan_latifi@yahoo.com
Telephone: +45-52-404772 Fax: +45-38-623782
Received: December 11, 2015
Peer-review started: December 14, 2015
First decision: January 4, 2016
Revised: January 9, 2016
Accepted: January 27, 2016
Article in press: January 29, 2016
Published online: March 18, 2016
Processing time: 89 Days and 14.5 Hours
Abstract

AIM: To investigate knee awareness and functional outcomes in patients treated with simultaneous bilateral vs unilateral total knee arthroplasty (TKA).

METHODS: Through a database search, we identified 210 patients who had undergone unilateral TKA (UTKA) and 65 patients who had undergone simultaneous bilateral TKA (SBTKA) at our institution between 2010 and 2012. All TKAs were cemented and cruciate retaining. The mean follow-up period was 3.2 (2 to 4) years. All the patients had symptomatic and debilitating unilateral or bilateral osteoarthritis for which all conservative and non-surgical treatments were failed, thus preoperatively the patients had poor functionality. All patients were asked to complete Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) questionnaires. The patients were matched according to age, gender, year of surgery, Kellgren-Lawrence score and pre- and postoperative overall knee alignment. The FJS and OKS questionnaire results of the two groups were then compared.

RESULTS: A mixed-effects model was used to analyze differences between SBTKA and UTKA. OKS: The mean difference in the OKS between the patients who had undergone SBTKA and those who had undergone UTKA was 1.5, which was not statistically significant (CI = -0.9:4.0, P-value = 0.228). The mean OKS of the SBTKA patients was 37.6 (SD = 9.0), and the mean OKS of the UTKA patients was 36.1 (SD = 9.9). FJS: The mean difference in the FJS between the patients who had undergone SBTKA and those who had undergone UTKA was 2.3, which was not statistically significant (CI = -6.2:10.8, P-value = 0.593). The mean FJS of the SBTKA patients was 59.9 (SD = 27.5), and the mean FJS of the UTKA patients was 57.5 (SD = 28.8).

CONCLUSION: SBTKA and UTKA patients exhibited similar joint functionality and knee awareness. Our results support the use of SBTKA in selected patients suffering from clinically symptomatic bilateral osteoarthritis.

Keywords: Unilateral total knee arthroplasty; Knee awareness; Patient-reported outcomes; Simultaneous bilateral total knee arthroplasty; Forgotten Joint Score

Core tip: We investigated the functional outcomes and knee awareness of patients who had undergone simultaneous bilateral compared with those who had undergone unilateral total knee arthroplasty (TKA). To accomplish this, we used the well-known Oxford Knee Score and the recently introduced Forgotten Joint Score (FJS). The FJS is based on a novel concept, or a patient’s ability to forget about an artificial joint as a result of successful treatment; this result is considered as the ultimate goal of joint replacement surgery. No differences in final outcomes were observed between the groups. Therefore, individuals for whom bilateral TKA is indicated should be offered this option.