Abstract
Here we introduce the Insight System, which allows an appropriate femoral position to be maintained during surgery. Total knee arthroplasty (TKA) is usually performed by two surgeons. The knee joint is approached via the mid-vastus, and the Insight System is fixed on the femur. We can then change the position of the knee easily using a foot switch.
At our hospital, we performed TKA using the Insight System (Scorpio NRG PS type for 49 knees, and Scorpio TS for one knee) in 45 patients (50 knees) with an average age of 76.2 yr. At the final follow-up (from 8 months to 5.5 years after surgery), the average knee flexion angle was 123 degrees, the average knee extension was -4.3 degrees, and the JOA score was 85.7 points. In the final X-ray component positions, the average α angle was 96.5 degrees, the average β angle was 89.5 degrees, the average γ angle was 2.3 degrees, and the average δ angle was 84.5 degrees. The average operation time was 117 min (range 90 to 150 min). The complications in this series were two fractures of the femoral medial condyle and one case of deep infection.
We were able to perform the operations stably using the Insight System, and this is considered to be a useful instrument at the institutions concerned.
