The UK National Joint Registry (NJR) is the single largest joint registry in the world, enrolling 1.3 million patients, with up to 17 years follow-up. This study used the NJR 17th annual report to calculate the pooled mean survival estimates for total knee (TKA), partial knee (PKA) and patellofemoral (PFA) arthroplasty according to brand and fixation.1
All-cause mean construct survivorship for TKA was 96.7% at 10 years and 95.4% at 15 years compared to PKA survivorship of 89.8% and 80.7% at 10 and 15 years, respectively. At 10 years cementless PKA demonstrated significantly better survivorship than cemented PKA (92.7% Vs 88.2%) (p < 0.001). There were no 15-year data for cementless PKA.
The age demographic of patients receiving PKA has typically been younger. This is demonstrated by the UK NJR where the mean age of PKA patients is just 58 years. When examining this younger demographic of patients of <65 years the benefits of cementless PKA fixation were amplified. The 10-year survivorship of cemented PKA was just 86.7% in this age group compared to 92.4% in those aged >65 years (p < 0.001). By contrast, the 10-year survivorship of cementless PKA was 91.2% in those ages <65 years versus 93.1% in those >65 years (p < 0.001).
The authors concluded that this “evidence suggests the previously less popular uncemented fixation technique could offer improved joint survival in these (younger) patients.”