Thoracic Interlaminar Epidural Injections in Managing Chronic Thoracic Pain: A Randomized, Double-Blind, Controlled Trial with a 2-Year Follow-Up

Abstract

Background: Reports of prevalence of spinal pain indicate the prevalence of thoracic pain in approximately 13% of the general population compared to 32% of the population with neck pain and 43% of the population with low back pain during the past year. Even though, thoracic pain is less common than neck or low back pain, the degree of disability resulting from thoracic pain disorders seems to be similar to other painful conditions. Interventions in managing chronic thoracic pain are also less frequent, leading to the paucity of literature about various interventions in managing chronic thoracic pain. Thoracic intervertebral discs and thoracic facet joints have been shown to be pain generators, even though thoracic radicular pain is very infrequent. Thoracic epidural injections are one of the commonly performed procedures in managing thoracic pain. The efficacy of thoracic epidural injections has not been well studied. Study Design: A randomized, double-blind, active controlled trial. Setting: Private interventional pain management practice and specialty referral center in the United States. Objective: The primary objective was to assess the effectiveness of thoracic interlaminar epidural injections in providing effective pain relief and improving function in patients with chronic mid and/ or upper back pain. Methods: One hundred and ten patients were randomly assigned into 2 groups with 55 patients in each group receiving either local anesthetic alone (Group I) or local anesthetic with steroids (Group II). Randomization was performed by computer-generated random allocation sequence by simple randomization. Outcomes Assessment: Outcomes were assessed utilizing Numeric Rating Scale (NRS), the Oswestry Disability Index (ODI) 2.0, employment status, and opioid intake. The patients experiencing greater than 3 weeks of significant improvement with the first 2 procedures were considered as successful. Others were considered as failed participants. Significant improvement was defined as a decrease of greater than 50% NRS scores and ODI scores with measurements performed at baseline, 3, 6, 12, 18, and 24 months post treatment. Results: Significant improvement was seen in 71% in Group I and 80% in Group II at the end of 2 years with all participants; however, improvement was seen in 80% and 86% when only successful patients were considered. Therapeutic procedural characteristics showed 5 to 6 procedures per 2 years with total average relief of 80 weeks in Group I and 78 weeks in Group II in the successful patient category; whereas, it was 71 and 72 weeks when all patients were considered. Limitations: Limitations of this assessment include lack of a placebo group.Conclusions: Based on the results of this trial, it is concluded that chronic thoracic pain of non-facet joint origin may be managed conservatively with thoracic interlaminar epidural injections with or without steroids. Key words: Chronic thoracic pain, chest wall pain, disc herniation, discogenic pain, radiculitis, thoracic interlaminar epidural injections, steroids, local anesthetic