The GSB II (Sutzer Medica, Winterthur, Switzerland) knee prosthesis ranks between the minimally constrained condylar prostheses and the fully constrained hinges. The senior author (T.R.S.) used this prothesis in 47 patients (54 knees) With a maximum follow-up of 18 years (mean, 7.8 years). The mean patient age was 75 years (range, 61-94 years). The 10- and 18-year cumulative life-table survival rates were 95.7% and 88.1% for prosthesis removal or infection, 87.41% and 76.8% for patient dissatisfaction, and 81.5% and 71.3% for Hospital for Special Surgery score <70 or infection (95% confidence interval). The cumulative rate of infection after 10 and 18 years was 4.3% and 11.6% based on the life-table survival analysis. The only indication for this type of prosthesis in a primary arthroplasty is a knee with severe deformity, bone loss, or ligament deficiency.