Up to 20% of patients are dissatisfied after total knee arthroplasty (TKA). There are many contributing factors. The relationship between preoperative osteoarthritis (OA) severity and outcome post TKA remains unclear. This review explores the relationship between preoperative OA severity with patient reported pain, function and satisfaction post TKA.
A pre-registered systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Major databases were searched until September 2017. We included studies assessing adults undergoing TKA for OA. Minimum follow-up was 6 months. Methodological quality assessment was conducted using the Newcastle-Ottawa Scale.
Twenty cohort studies with 7478 patients were included. There were 16 good, one fair and three poor quality studies. Knee OA was most commonly reported according to the Kellgren and Lawrence tool. Ten studies showed statistically significant pain outcomes for those with worse preoperative OA. This was supported by meta-analysis of the Knee Society Score pain change scores to final follow-up for those with Kellgren and Lawrence grade 4 OA. Six studies showed statistically significant results for various aspect of functional recovery, although meta-analysis of Knee Society Score function change scores identified no difference. Meta-analysis of final follow-up pain and function scores alone yielded no significant difference. Patients with more severe preoperative OA were more likely to be satisfied. There were no studies demonstrating that less severe OA resulted in better pain, function or satisfaction.
Review of available research indicates that TKA for OA improves pain, function and satisfaction. Those with more severe preoperative radiological knee OA benefit most.