Background: Chronic post-operative pain is a well-recognized problem after various types of surgery, but little is known about chronic pain after orthopedic surgery. Severe pre-operative pain is the primary indication for total hip arthroplasty (THA). Therefore, we examined the prevalence of chronic pain after THA in relation to pre-operative pain and early post-operative pain.
Methods: A questionnaire was sent to 1231 consecutive patients who had undergone THA 12-18 months previously, and whose operations had been reported to the Danish Hip Arthroplasty Registry.
Results: The response rate was 93.6%. Two hundred and ninety-four patients (28.1%) had chronic ipsilateral hip pain at the time of completion of the questionnaire, and pain limited daily activities to a moderate, severe or very severe degree in 12.1%. The chronic pain state was related to the recalled intensity of early post-operative pain [95% confidence interval (CI), 20.4-33.4%] and pain complaints from other sites of the body (95% CI, 20.7-32.1%), but not to the pre-operative intensity of pain.
Conclusion: Chronic pain after THA seems to be a significant problem in at least 12.1% of patients. Our results suggest that genetic and psychosocial factors are important for the development of chronic post-THA pain.