Prediction of Pain in Total Knee Arthroplasty

Is Preoperative Pain Response Upon Tonic Heat Stimulation Predictive for Pain After Total Knee Arthroplasty?

In this consecutive, prospective cohort study trial the investigators evaluate if preoperative pain response upon heat stimulation is predictive for acute and subacute postoperative pain after total knee arthroplasty.

The preoperative heat stimulation consists of short and long tonic heat stimulation. Pain response is evaluated with an electronic visual analog scale.

Furthermore the investigators evaluate other factors possibly predictable for acute and subacute postoperative pain after total knee arthroplasty - demographic factors, preoperative pain related factors, psychosocial factors (Hospital Anxiety and Depression Scale and Pain Catastrophizing Scale).

Inclusion Criteria:

• Ethnic danes, above 18 years and able to give informed consent scheduled for primary, unilateral total knee arthroplasty.

Exclusion Criteria:

• Bilateral / revision arthroplasty
• Disease affection central or peripheral nerve function
• Alcohol and medical abuse
• Daily use of opioids or glucocorticoids
• Malignancy
• BMI > 40
• Depression
• Dementia or other cognitive dysfunction