A comparison of predictors and intensity of acute postsurgical pain in patients undergoing total hip and knee arthroplasty

Abstract

Background

Acute pain is an expected result after surgery. Nevertheless, when not appropriately controlled, acute pain has a very negative impact on individual clinical outcomes, impairing healing and recovery, and has clear consequences on health care system costs. Augmenting knowledge on predictors and potentially modifiable determinants of acute postsurgical pain can facilitate early identification of and intervention in patients at risk. However, only a few studies have examined and compared acute pain after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The aim of this study was to compare THA and TKA in acute postsurgical pain intensity and its predictors.

Methods

A consecutive sample of 124 patients with osteoarthritis (64 undergoing THA and 60 TKA) was assessed 24 hours before (T1) and 48 hours after (T2) surgery. Demographic, clinical, and psychological factors were assessed at T1, and acute postsurgical pain experience was examined at T2. Additionally, the same hierarchical regression analysis was performed separately for each arthroplasty type.

Results

TKA patients reported higher levels of acute postsurgical pain compared with THA (t=8.490, p=0.004, d=0.527, 95% confidence interval, 0.196–0.878). In the final THA predictive model, presurgical pain was the only variable approaching significant results (t[57]=1.746, β=0.254, p=0.086). In the final TKA predictive model, optimism was the only predictor of pain (t[51]=−2.518, β=−0.339, p=0.015), with emotional representation (t[51]=1.895, β=0.254, p=0.064) presenting a trend toward significance.

Conclusion

The current study is the first examining THA and TKA differences on acute postsurgical pain intensity and its predictors using a multivariate approach. Results from this study could prove useful for the design of distinct interventions targeting acute postsurgical pain management depending on whether the site of arthroplasty is the hip or the knee. Finally, the current results also support the argument that these two surgeries, at least with regard to acute pain, should be approached separately.

Keywords:

• acute post-surgical pain
• total knee arthroplasty
• total hip arthroplasty
• psychological factors
• multivariate analyses
• presurgical psychological intervention

Acknowledgments

This work was supported by two grants (SFRH/BD/36368/2007 and SFRH/BPD/103529/2014) from the Portuguese Foundation of Science and Technology.

Author contributions

All authors discussed the results and commented on the manuscript. All authors made substantial contributions to conception and design, acquisition of data, and analysis and interpretation of data. All authors contributed toward data analysis, drafting and critically revising the paper and agree to be accountable for all aspects of the work.

Disclosure

We declare that none of the authors have any financial or other relationships that might lead to conflict of interest. The authors report no conflicts of interest in this work.