No difference in patient preference for medial pivot versus posterior-stabilized design in staged bilateral total knee arthroplasty: a prospective study

Purpose

Medial pivot (MP) TKA has been shown to mimic normal knee kinematics with long-term survivorship comparable to most contemporary TKA. However, there are inadequate evidences to suggest its superiority in terms of patient preference and satisfaction. The aim of this study is to compare the MP with posterior-stabilized (PS) TKA in terms of patient preference and satisfaction.

Methods

46 patients with staged bilateral TKA were recruited. TKA with MP or PS design was performed at interval of 6–12 months. Patient preference, patient satisfaction score (0–100), Forgotten Joint Score (FJS), range of motion (ROM), Pain Score, Knee Society Score (KSS), Knee Function Score (KFS) and WOMAC Score were compared at up to 12 months.

Results

The mean age was 70 and 69.6% were female. There was no difference in all preoperative parameters, operative time and length of stay between two knees. No difference was found in in range of motion and all outcome scores at 6 months and 12 months. Satisfaction score was similar for the two designs (82 vs 85, p = n.s.) at 1 year after the second TKA. Proportion of patients with preference on one design over another was not significantly different (28.9 vs 35.6%, p = n.s.).

Conclusions

There is no evidence to support the superiority of MP TKA over PS TKA in terms of preference and satisfaction. The choice between MP TKA versus PS TKA maybe more a surgeon’s preference than a patient’s preference based on current evidence.