Abstract
Which parameters are related with a forgotten knee after TKA?
The operated knee was said forgotten when it was similar to the normal controlateral knee in all situations.
When a restriction existed, the knee was considered as not forgotten.
470 patients operated with a stabilised mobile bearing knee were examined with a minimal follow up of 5 years and answered to this question.
4 groups of parameters: patient, prosthesis, surgery and post operative care were compared to the binary answer to the forgotten knee question.
48% of the patients had a forgotten knee one year after the TKA;
The following factors had a significant negative correlation with the forgotten knee:
-
low SF12 psychological profile; Patellofemoral dysplasic arthritis (p = 0,01);
-
femoral oversizing (p=0,001);
-
tight extension gap, femoral lengthening, tourniquet time; overcorrection superior to 2°(p = 0,02).
We found no correlation between the following factors and the forgotten knees:
-
gender, BMI, approach, cemented or not, patellar resurfacing; preoperative Oxford and Knee Society knee scores;
The forgotten knee is a simple objective clinical item because the answer to the question is binary and does not accept any unprecision. It is highly correlated with surgical scores and patients expectation scores (p = 0,0001).
The forgotten knee is a painless and asymptomatic knee identical to a normal knee.
Surgical factors have the highest infiuence on this parameter compared to patient or prosthetic related factors.
Correspondence should be addressed to: EFORT Central Office, Technoparkstrasse 1, CH – 8005 Zürich, Switzerland. Tel: +41 44 448 44 00; Email: office@efort.org
Author: Michel Bercovy, France
E-mail: mbercovy@noos.fr
