To examined the level of patient knowledge and their perspectives about the controversial issues in total knee arthroplasty (TKA), and to evaluate the effect of a relevant explanation about the issues on the patient preferences for their particular option.

One hundred patients who visited our clinic and decided to undergo TKA were asked to complete a questionnaire asking about their knowledge and preference for 4 controversial issues: 1) surgical timing of the bilateral TKAs, 2) use of computer assisted surgery, 3) use of minimal invasive surgery, and 4) use of ceramic femoral component. The patients completed the same questionnaire after the advantages and disadvantages of each option had been explained using an explanatory document designed based upon what was documented in the literature.

The patients were not well-informed about the issues and received their information through a non-professional source. The patients tended to prefer new options with claimed promises before an explanation. The patients preferred the options with safety, accuracy, and proven evidence after an explanation. Male patients tended to prefer simultaneous TKAs more than female patients. Younger patients preferred ceramic femoral component claimed to have better longevity more than older patients did.

This study demonstrates that patients' knowledge of the current controversial issues is very limited, and that patient preferences would be significantly changed if they were given an explanation from a physician. Balanced information should be given to patients in order for them to reach a fair decision.