Posterior stabilised total knee arthroplasty is associated with improved post-operative knee specific function, health related quality of life and greater satisfaction when compared to cruciate retaining protheses.

purposeTo assess whether there were differences in knee specific function, health related quality of life (HRQoL), and satisfaction between patients with a cruciate retaining (CR) or a posterior stabilised (PS) total knee arthroplasty (TKA) at 1 and 2 years postoperatively.

methodsA retrospective review of TKA (CR and PS) patients from a prospectively collected arthroplasty database. Patient demographics, body mass index and ASA grade, Oxford knee score (OKS) and EuroQol 5-dimension (EQ-5D) 3-level, which was used to assess HRQoL, were collected preoperatively and 1 year and 2 years postoperatively. Regression was used to adjust for confounding factors.

resultsThe sample included 3122 TKA, of which 1009 (32.3%) were CR and 2112 (67.7%) were PS. The PS group were more likely to be female (odd ratio (OR) 1.26, p = 0.003) and undergo resurfacing of the patella (OR 6.63, p < 0.001). There was a significantly greater improvement in the 1 year OKS in the PS group (mean difference (MD) 0.9, p = 0.016). The PS TKA was independently associated with a greater 1 year (MD 1.1, 95% CI 0.4 to 1.9, p = 0.001) and 2 years (MD 0.8, p = 0.037) post-operative improvements in OKS. PS TKA was also independently associated with a greater 1 year (MD 0.021, p = 0.024) and 2 years (MD 0.022, p = 0.025) post-operative and change in EQ-5D utility compared to the CR group. The PS group was more likely to be satisfied with their outcome at 1 year (OR 1.75, p < 0.001) and at 2 years (OR 1.38, p = 0.001) when adjusting for confounders.

conclusionPS TKA was associated with a better knee specific function and HRQoL when compared to CR, but the clinical significance of this is not clear. However, the PS group was more likely to be satisfied with their outcome compared to the CR group.