CRUCIATE RETAINING VERSUS CRUCIATE SUBSTITUTING KNEE REPLACEMENT WITH THE PCL CUT; A PROSPECTIVE, RANDOMIZED CONTROLLED TRIAL

Abstract

This study was performed to compare the clinical outcomes and radiographic changes between patients with cruciate retaining (CR) and cruciate substituting (CS) total knee replacements (TKR) where the PCL was cut in both groups.

From 1997 to 2001, 114 patients (79 females and 35 males) were enrolled in this study. Patients were blindly randomized into two groups, group 1 having a CR TKR and group 2 having a CS TKR. After surgery patients were followed up at six weeks, one year and at five years. The evaluation parameters at the 5 year assessment included the Oxford Knee Questionnaire, American Knee Society scoring system, SF-12 questionnaire and weight bearing radiographs of the knee, with anteroposterior and lateral views.

There were 80 patients at the time of five year follow up. Of the other patients, 26 had died and 10 were either too ill to attend or did not respond to a follow up request. The average patient follow up was for 77 months (ranging from 51 to 96 months). There was no statistical difference between the two groups in the Oxford Knee Questionnaire, American Knee Society scoring system or the SF-12. Radiological assessment showed no statistical difference in radiolucent lines in either group. At five year follow up, one knee in the CS group had been revised for deep infection. The patient required a two stage revision procedure.

Our study has shown no statistical difference in the five year results for a CR TKR or CS TKR. This suggests that a non-functioning PCL does not affect the performance of a CR TKR.