Priority 11 from the Revision Knee Replacement PSP

UNCERTAINTY: What are the best ways to investigate the causes of pain following a knee replacement?  (JLA PSP Priority 11)
Overall ranking 11
JLA question ID 0093/11
Explanatory note This is related to the top ranking priority, but submissions were focussed specifically on best modalities for investigation and diagnosis of persistent pain. 
Evidence

 None identified
Health Research Classification System category Musculoskeletal
Extra information provided by this PSP
Original uncertainty examples How do we know the patients pain is caused by the problem with the knee replacement? ~  What is the best group of tests to fully assess a knee replacement which is causing symptoms again ~ Patients who remain in pain longterm are often told their xrays look ‘fine’. Does this indicate that the Xray is not the optimum test for such patients? ~ Can thresholds, based on patient factors and level of pain be created  for proceeding with revision surgery in patient with persistent pain?
Submitted by See data spreadsheet on JLA website 
PSP information
PSP unique ID 0093
PSP name Revision Knee Replacement
Total number of uncertainties identified by this PSP. 32  (To see a full list of all uncertainties identified, please see the detailed spreadsheet held on the JLA website)
Date of priority setting workshop 21 May 2019