Moderate evidence supports that patients with select chronic pain conditions have less improvement in patient reported outcomes with TKA.

Rationale
One moderate quality paper (Boyle 2014) used low back pain as one form of chronic pain and demonstrated less good outcomes. Another moderate quality paper (Perruccio 2012) showed less good outcomes after total knee arthroplasty for patients with multiple joint and/or spine pain. The two retain a moderate quality of evidence leading to the recommendation that moderate evidence supports that patients with select chronic pain conditions have less improvement in patient reported outcomes with total knee arthroplasty.
 
  1. Boyle,J.K., Anthony,I.C., Jones,B.G., Wheelwright,E.F., Blyth,M.J.G. Influence of low back pain on total knee arthroplasty outcome. Knee 2014/3; 2: 410-414
  2. Perruccio,A.V., Power,J.D., Evans,H.M., Mahomed,S.R., Gandhi,R., Mahomed,N.N., Davis,A.M. Multiple joint involvement in total knee replacement for osteoarthritis: Effects on patient-reported outcomes. Arthritis Care Res.(Hoboken.) 2012/6; 6: 838-846