Acute pain; trigger point; neurosurgery
Introduction: The opioid epidemic has launched the United States into a public health crisis, resulting in a greater emphasis on non-opioid multimodal pain control methods.
At our institution, postoperative posterior neck stiffness and myofascial pain is a common concern after anterior cervical discectomy and fusion or anterior cervical corpectomy with fusion surgery (hereinafter ACS), likely due to prolonged intraoperative positioning in neck extension. Studies have shown successful analgesic outcomes of trigger point injections with local anesthetic for generalized myofascial pain.1-2 This retrospective pilot study aimed to evaluate whether trigger point injections with bupivacaine decreases postsurgical pain compared with traditional therapies in patients undergoing ACS and thereby decrease the amount of opioid medication used.
Methods: After IRB approval, we retrospectively reviewed medical records of all patients who received ACS from January 2019 to March 2020 at a single university hospital. We identified patients who received trigger point injections (TP) versus standard care (SC). We excluded patients if TP was performed >3hr from surgery, in recovery for opioid use disorder, underwent a posterior approach, staged surgery, or sustained cervical trauma. The primary outcomes were pain control through the Visual Analog Scale (VAS) and calculated oral morphine equivalents (OME) taken at 6, 12, and 24 hours post-operatively. Secondary outcomes included length of stay (LOS).
Results: 137 patients received anterior cervical surgery (100 SC, 37 TP), 62 were excluded. A total of 75 (47 SC, 28 TP) patients were included in this study. The average OME at 6 hours significantly decreased when comparing SC vs TP (32 vs 22, p=0.025). There was no significant difference in average VAS at all time points and average OME at 12 and 24 hours (Table 1). 50% of patients were discharged by 18 hours.
Discussion: Our results suggest that TP with bupivacaine significantly reduce opioid consumption within 6 hours of the postoperative period, without increasing overall pain level. There is an opportunity for TP to be included in non-opioid multimodal pain regimens for postoperative myofascial neck pain, especially during the opioid crisis. Limitations of this retrospective study were the small number of study participants, that many patients were discharged before 18 hours and some may have been on chronic pain therapy. The identified limitations will help inform our future investigations and design a prospective randomized control study.