Clinical Efficacy of Tender Point Infiltration (TPI)for Management of Acute and Subacute Zoster-Associated Pain: A Retrospective Analysis.

BACKGROUND:Zoster-associated pain (ZAP) represents an important medical, social, and economic problem. The treatment approach for ZAP continues to be challenging. Tender point infiltration (TPI) with local anesthetic and steroids has been demonstrated to have potential in the treatment of severe pain, but there are rare reports of the efficacy and security of TPI for acute and subacute ZAP. OBJECTIVES:The aim of this study was to retrospectively analyze the efficacy of TPI for pain control in acute and subacute ZAP. STUDY DESIGN:Retrospective case series. METHODS:Medical records of 152 patients who underwent TPI for acute and subacute herpes zoster pain were reviewed. The patients were divided into 2 groups: acute TPI group (TPI within 30 days after zoster onset) and subacute TPI group (TPI between 30 and 90 days after zoster onset). The numeric rating scale (NRS), effective rate, frequency of TPI and rate of medication discontinuation during the follow-up period of 3 months were retrospectively analyzed. RESULTS:The NRS score significantly decreased from 7.80 ± 1.05 before TPIs to 0.97 ± 0.68 in the acute TPI group (P < 0.001) and was decreased from 5.76 ± 1.07 to 1.12 ± 0.70 in subacute TPI group (P < 0.001). The effective rate was 92.2% in acute TPI group and was 90.7% in subacute TPI group (P = 0.734). The rate of medication discontinuation at month 1 and month 3 was higher in the acute TPI group than in the subacute TPI group (P < 0.05). The frequency of TPI in acute TPI group (1.49 ± 0.79) was less than subacute TPI group (3.09 ± 1.02) (P < 0.001). A small proportion of the patients had mild complications, and all resolved over time after TPIs. No severe adverse events occurred during or after TPI procedures. LIMITATIONS:Retrospective design without a control group, short period of follow-up, and the small number of patients. CONCLUSIONS:TPI can be a useful and safe option for the control of acute and subacute ZAP with high feasibility. Early application of TPI in the acute phase of herpes zoster pain may show better clinical outcomes.