Knee scores in a 'normal' elderly population.

Many scoring instruments are now available for assessment of outcome after knee replacement. We performed a community study to record the three most frequently used knee scores in the UK in a 'normal' elderly population with no history of knee, hip, spine or lower limb disorder. The Oxford Knee Score (OKS), Bristol Knee Score (BKS), and American Knee Society Score (AKSS) were recorded in 100 volunteers whose mean age was 72 years. Normalised median scores in this population were 97% (42-100), 96% (69-100) and 98% (46-100), respectively. Significant negative correlations were found to exist between knee score and increasing age (P<0.001) and presence of coexistent 'major' medical conditions (P<0.001). The 'function' component of each score was the aspect of the score most influenced by these demographic variables. Comparison of outcomes after knee replacement on the basis of knee scores should take account of demographic variables.