SYMPATHETIC MODULATION VIA ULTRASOUND-GUIDED STELLATE GANGLION BLOCK IN POST-STROKE UPPER LIMB COMPLEX REGIONAL PAIN SYNDROME: A PROSPECTIVE PILOT INTERVENTIONAL STUDY

R.S. Sharma, A. Panwar | Department of Anaesthesiology, Pain Medicine & Critical Care, All India Institute of Medical Sciences, Gorakhpur, India

Abstract

Background and Aims. Post-stroke Complex Regional Pain Syndrome (CRPS) represents a severe neuropathic complication associated with maladaptive sympathetic–sensory coupling and central sensitization. Therapeutic options remain limited, and high-quality evidence supporting interventional sympathetic modulation in this population is scarce. This study investigated whether ultrasound-guided stellate ganglion block (SGB) provides sustained analgesic and psychological benefit in post-stroke upper limb CRPS.
Methods. In this prospective pilot interventional study, 25 adults meeting Budapest diagnostic criteria for CRPS underwent ultrasound-guided SGB with 6 mL 1% preservative-free lignocaine plus 8 mg dexamethasone. Primary endpoints were changes in Numeric Rating Scale (NRS) and Douleur Neuropathique 4 (DN4) scores at baseline, immediately post-procedure, 1 month, and 3 months. Secondary outcomes included Global Perceived Effect (GPE) and Hospital Anxiety and Depression Scale (HADS). Statistical comparisons were performed using Wilcoxon signed-rank testing.
Results. The mean NRS significantly decreased from 7.6 ± 1.1 at baseline to 3.2 ± 1.4 immediately post-intervention (p < 0.001), with sustained reduction at 1 month (3.5 ± 1.6) and 3 months (3.8 ± 1.7; both p < 0.001). DN4 scores declined from 6.8 ± 1.2 to 3.1 ± 1.3 at 3 months (p < 0.001). Clinically meaningful pain relief (≥50% reduction) was achieved in 72% of patients. HADS scores improved from 15.2 ± 3.4 to 9.1 ± 2.8 (p < 0.01). No major adverse events occurred.
Conclusions. Ultrasound-guided SGB produced robust and sustained neuropathic pain reduction, supporting the role of targeted sympathetic modulation in post-stroke CRPS. These findings provide mechanistic and clinical justification for randomized controlled trials evaluating SGB as part of multimodal post-stroke pain management.