Abstract
Approximately one-fifth of patients are not satisfied with total knee arthroplasty (TKA). Preoperative variables associated with poorer outcomes are severity and chronicity of pain and psychological disease, which may present as anxiety and depression. It is unclear whether this is constitutional or the result of knee pain. To address this, we explored the association of anxiety and depression with knee disability before and after TKA.
Forty patients undergoing TKA completed Hospital Anxiety and Depression Scale (HADS) and Oxford Knee Scores (OKS) preoperatively and at three and six months postoperatively. Both were elevated preoperatively and improved significantly post-operatively (P<0.001). The severity of preoperative anxiety and depression was associated with worse knee disability (coefficient −0.409, p=0.009). Postoperatively reduction in anxiety and depression was associated with improvement in knee disability after three (coefficient −0.459, p=0.003) and six months (coefficient −0.428, p=0.006).
The difficulty in interpreting preoperative anxiety and depression and the outcome of TKA is establishing whether they are the cause or effect of pain in the knee. As anxiety and depression improves with knee pain and function, this study suggests that knee pain contributes to the psychological symptoms and that a successful TKA offers an excellent chance of improving both.
