Results for the Mobile-Bearing Rotating Platform Knee: Minimum 10-Year Follow-Up
Polasan Santanapipatkul MD*, Keerati Chareancholvanich MD**
Affiliation : * Department of Orthopaedic and Rehabilitaion, Faculty of Medicine Siriraj Hospital, Bangkok, Thailand ** Department of Orthopaedic and Rehabilitaion, Faculty of Medicine, Siriraj Hospital, Bangkok, Thailand
Background : The mobile bearing knee was introduced in 1977. Since then, many reports have examined the long-term results
obtained with the mobile bearing knee. Some authors reported significant improvement results and longevity for the mobile-
bearing knee over the fixed-bearing knee, but some authors reported no significant improvement over the fixed-bearing knee.
Many reports have examined the longevity and functional outcomes in patients treat with the mobile-bearing knee. The longest
follow-up was 20 years follow-up, but no study has examined long-term outcomes in Thailand. Our study reports the long-
term results obtained with a mobile-bearing knee LCS system after at least 10-years of follow-up.
Objective : To study the long-term results achieved with a mobile-bearing knee LCS system after at least 10-years of follow-
up.
Material and Method: The twenty-one patients were included in this prospective-cohort study. Range of motion, patellar
score, American Knee Society scores and the radiographicevaluation. Patients were evaluated at pre-operatively and 6
months, 1 year, 5 years, 10 years after surgery.
Results : After at least 10 years of follow-up, eighteen patients showed no signs of radiographic loosening. The patellar score,
knee score and functional score decreased over time. However, the patellar score increased significantly compared with pre-
operative values. Only two patients underwent patellar resurfacing, the scores were similar to those reported in other studies
at 5 years after surgery. This trend was also observed for the knee score, although it was not significant. This same trend was
observed for the functional score and was significant at 10 years after surgery.
Conclusion : The mobile-bearing rotating platform knee achieves a good knee score and fair functional score after 10 years
follow-up. Additional multi-center studies will be necessary to collect more data.
Keywords : Mobile-bearing knee, LCS knee, Long-term results
