Long-term outcomes of amputation in the treatment of complex regional pain syndrome

Aims: Amputation as a form of treatment for patients with complex regional pain syndrome (CRPS) remains controversial. The aim of this study was to assess the long-term outcomes of amputation in patients with CRPS according to the criteria set by the core outcome measurement set for complex regional PAin syndrome Clinical sTudies (COMPACT) group. Methods: This was a single-centre retrospective case series involving patients who underwent amputation for CRPS type I or II between January 2012 and December 2022. The primary outcome measure was the numerical rating scale (NRS) pain score in the residual limb at rest. Secondary outcomes included pain during activity, the patient's global impression of the change in pain, health-related quality of life, self-efficacy, pain catastrophizing, and phantom limb pain. Results: The study included 11 patients: seven with CRPS type I and four with type II. Three patients underwent amputation involving the upper limb, seven patients had an amputation of the lower limb, and one had amputations of both an upper and lower limb. At a median follow-up of 8.1 years (IQR 2.2 to 11.9), the median NRS pain score at rest in the residual limb was 4.0 (IQR 2.0 to 7.0). Seven patients reported an improvement in pain; six had a considerable improvement. The median EuroQol five-dimension five-level questionnaire score for health-related quality of life was 0.246 (IQR 0.102 to 0.640). Nine patients had phantom limb pain with a median NRS pain score of 5.0 (IQR 1.0 to 8.0). Conclusion: Amputation as a last resort can reduce the level of pain in a proportion of patients with CRPS. The high incidence of of phantom limb pain poses a challenge to the overall effective management of pain in these patients. Although the level of pain improved postoperatively in most patients, the overall health-related quality of life remained low.