Efficacy of continuous lumbar sympathetic nerve block for cold allodynia in patients with lumbar disc herniation

Cold allodynia is a complaint in patients with lumbar disc herniation (LDH), and significantly impairs their quality of life. We treated cold allodynia with continuous lumbar sympathetic nerve block (CLSNB) with patientcontrolled analgesia (PCA) and determined the therapeutic outcome in long-term follow-up. Eight patients with a median age of 52.0 years were enrolled between September 2013 and August 2014. These patients had long-term cold allodynia in their affected lower extremity, and did not respond to established treatments. CLSNB was finally performed. The patients were followed up for at least 24 weeks. The average cold allodynia score on the visual analog scale (VAS) declined significantly from 7.1 before treatment to 1.6 at discharge, 1.8 at 1 week after discharge, 3.2 at 4 weeks, 4.0 at 8 weeks, and 4.6 at 24 weeks (P<0.05). All patients obtained immediate continuous cold relief during hospitalization. Seven of 8 patients had satisfactory pain relief at 1 week after discharge, 6 of 8 at 4 weeks, 5 of 8 at 8 weeks, 4 of 8 at 12 weeks, and 4 of 8 at 24 weeks. There were no reported complications. CLSNB is an effective and safe technique in treating cold allodynia in patients with LDH, and can provide long-term benefit.