Abstract
Introduction
A modern total knee replacement system was introduced in 2012 in order to improve the mechanics of total knee replacement (TKR). The purpose of this study was to assess the early clinical and radiographic outcomes of patients who have been treated with this modern TKR system at two years postoperatively.
Methods
Patients who received this TKR system between June of 2012 and September of 2014 were included in this prospective registry-based follow-up study. Demographics, component, and surgical data were collected. Radiographic outcomes were also assessed. Patient reported outcome measures (PROMs) of all patients with 2-year follow-up data were collected. Reasons for revision and overall survival at 2-years were evaluated.
Results
The study population consisted of 290 patients (307 knees). The mean age was 66 years and 61% were women. 250 patients received cruciate retaining and 57 patients posterior stabilized implants. The median tibiofemoral axis was in 4° valgus and the femoral component was in 5° valgus and 2° flexion. The median coronal and sagittal alignment of the tibial component was −1° varus and −5° slope, respectively. Most patients had tibial components that fit the tibial resection. At one year, 7 of 80 knees had a radiolucency in the tibia or femur. At two years, two of 30 knees had a radiolucency in the tibia or femur.
Mean PROMs for thirty-six patients at two years were: EQ-5D WHI 0.76 (range 0.31–1.00), EQ-5D VAS 82 (range 48–98), UCLA activity score 5.3 (range 2–10), KOOS pain 70.9 (22–100), symptoms 69 (14–96), ADL 74.2 (18–100), sports 51.4 (0–100), and QoL 59.8 (0–90). Cumulative 2-year implant survival was 97.1%. There were 7 revisions for infection and 2 revisions due to an unsatisfactory clinical outcome.
Conclusion
Clinical and radiographic outcomes at two years were good, and overall implant survival was excellent.