gms | German Medical Science

Objective: Complex regional pain syndrome (CRPS) is a common pain condition which usually occurs after trauma or operation on a limb. It is characterized by pain, functional impairment, and trophic changes. Neurosurgical treatment is not widely offered. In this study the treatment with spinal cord stimulation (SCS) was evaluated over 24 months follow up.

Methods: A retrospective case analysis of 6 patients with CRPS was performed. Pain chronicity was recorded with the Mainz Pain Staging System (MPSS). Pain intensity (VAS), activity level and health-related quality of life (EQ-5D-5L), the actual mood state (ASTS), and treatment satisfaction (CSQ-8) were assessed. All patients received conventional pharmacological treatments including multimodal pain therapy through their local pain therapist or in specialized centers as well as physical therapy. A SCS electrode was implanted for trial stimulation. After successful trial a neurostimulator was implanted and connected to the electrode. Patients were retrospectively analyzed before implantation, and 6, 12 and 24 months postoperatively. Statistical analysis was performed using Mann- Whitney U and Wilcoxon rank-sum test.

Results: Patients median age was 43 years (range 36-54 years). The median MPSS Score was 3 of 3 indicating a very high pain chronicity. Median VAS before implantation of the neurostimulator was 8.8. A reduction to 7.8 after 6 months, 6.5 after 1 year, and 6.8 after 2 years was achieved (p=0.32). Median EQ-5D-5L index value before treatment was 0.27 (range 0.24-0.47) indicating a severely lowered quality of life. A significant improvement to 0.53 (range 0.26-0.76) after 6 months, 0.58 (range 0.26-1) after 1 year as well as after 2 years was seen (p=0.03). ASTS scale showed an increase of values for positive mood, and a reduction in values for sorrow, fatigue, anger, and desperation during the whole follow up period after implantation of the neurostimulator. The treatment satisfaction in the whole cohort with a median CSQ-8 value of 29.5 of 32 was very high.

Conclusion: The results of this small case series showed a significant improvement of the EQ-5D-5L after implantation of a neurostimulator. VAS reduction was not significant but a tendency towards reduced values was observed. We therefore conclude that SCS is an alternative option to relieve chronic pain and psychological distress originating from complex regional pain syndrome (CRPS) if conservative treatment modalities fail. The preoperative selection plays a crucial role for good results.