The efficacy of an interdisciplinary pain management program for complex regional pain syndrome compared to low back pain and chronic widespread pain: An observational study.

Background: Little research has assessed the efficacy of interdisciplinary pain management programs (IPMPs) for complex regional pain syndrome (CRPS), whereas evidence shows that IPMPs are effective for low back pain (LBP) and chronic widespread pain (CWP). This study aimed to determine whether outcomes following an IPMP differ for people with CRPS compared to LBP and CWP. In addition, we determined whether it is possible to predict IPMP outcomes using baseline characteristics.

Methods: People with CRPS (N = 66) who had completed a 3-week IPMP were compared with age- and gender- matched controls with LBP (N = 66) and CWP (N = 66). Measures of pain intensity, pain interference and psychological factors were extracted for pre- and post-program, and at 1, 6 and 12 months. Latent class analysis identified recovery trajectories for pain intensity and pain interference. Chi-square analyses assessed differences between diagnostic groups in recovery trajectories. Machine learning models were implemented to predict recovery trajectories from baseline scores.

Results: Two recovery trajectories for each dependent variable (pain interference and for pain intensity) were identified: good responders and poorer responders. Following IPMPs, 37% of people belonged to a good responder recovery trajectory for pain interference, and 11% belonged to a good responder recovery trajectory for pain intensity. Recovery trajectories were equal across the three diagnostic groups (CRPS, LBP, CWP) for pain interference (χ2=1.8, p=0.4) and intensity (χ = 0.2, p=0.9). Modelling to predict outcomes correctly classified 69% of cases for pain interference and 88% of cases for pain intensity recovery trajectories using baseline scores.

Conclusion: People with CRPS, LBP, and CWP experience similar benefits following an IPMP. This supports the use of IPMPs for people with CRPS.