Increased pain following surgery has long been linked to anxiety and "catastrophizing," an extreme response to stress.

In a new study presented today at the 2012 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS), 97 patients – and – who were about to undergo minimally invasive total knee replacement (TKR) surgery, completed a brief survey to quantify their level of , as well as their typical level of anxiety and potential for catastrophizing. Pain data was then collected for seven days following surgery.

Catastrophizing did not correlate with or pain medication use in either men or women, nor did a patient's level of acute anxiety.

However, men with anxiety traits – a high level of anxiety unrelated to a stressful event – had higher post-operative pain ratings resulting in longer hospital stays. Women generally reported higher post-operative pain levels than men, and women were consistently less satisfied with pain control.

Further research is needed to identify patients most likely to have difficulty with TKR pain management.