Long-term clinical outcomes of medial pivot total knee arthroplasty for Asian patients: A mean 10-year follow-up study

Many Asian populations have a unique floor-based lifestyle that might cause mechanical stress of the knees. It is important to clarify the longevity of a medial pivot total knee arthroplasty, as its prosthetic design could cause mechanical stress onto the insert. The purpose of this study was to clarify the clinical results of medial pivot total knee arthroplasty for Asian patients in a 10-year follow-up study.

Consecutive, primary total knee arthroplasties (n = 257) were analyzed in the study using the medial pivot knee system. The clinical outcomes were assessed preoperatively and at the final follow-up. The patient-reported Forgotten Joint Score-12 and radiological outcomes were measured at the final follow-up. The survival rate was assessed with reoperation or revision as the end-point.

The mean follow-up period was 10.1 ± 1.7 years. The lost to follow-up was 4.5%. All clinical outcomes improved significantly after surgery (p < 0.001). The mean postoperative knee flexion was 118° ± 11° and the mean Forgotten Joint Score-12 was 59.7 ± 27 points. The radiolucent line was observed in 29 patients (11.3%), however there was no aseptic loosening noted. The survival rates with reoperation or revision were 96.3% or 98.4% at 10 years after the operation.

Medial pivot total knee arthroplasty used for Asian patients showed good longevity and patient-reported outcome measurement in a mean 10-year follow-up study. Medial pivot total knee arthroplasty has long-term stability among patients who have a floor-based lifestyle.

Level of evidence: III.