revalence of Facet Joint Pain in Chronic Low Back Pain in ostsurgical Patients by Controlled Comparative Local nesthetic Blocks

Objective: To evaluate the prevalence of facet joint pain in atients with chronic low back pain (CLBP) after surgical ntervention(s). Design: A prospective, nonrandomized, consecutive study. Setting: An ambulatory interventional pain management etting. Participants: The prevalence of facet joint pain was evaluted in patients with CLBP after various surgical intervenion(s) referred to an interventional pain management practice. he sample was derived from 282 patients with persistent LBP after various surgical intervention(s). Of these, 242 atients consented to undergo interventional techniques. A otal of 117 consecutive patients with chronic, nonspecific low ack pain, after lumbar surgical intervention(s) were evaluated ith controlled, comparative local anesthetic blocks. Interventions: Controlled, comparative local anesthetic locks (1% lidocaine or 1% lidocaine followed by .25% buivacaine) under fluoroscopic visualization using 0.5mL to lock each facet joint nerve. Main Outcome Measures: A positive response was defined s at least 80% reduction of pain with ability to perform reviously painful movements. A positive response was conidered to be pain relief from the lidocaine block lasting at least hour or at least 2 hours or greater than duration of relief with idocaine when bupivacaine was used. Controlled, comparative ocal anesthetic blocks were used to eliminate false-positive esults. Valid information is only obtained by performing conrolled blocks in the form of comparative local anesthetic locks, in which, on 2 separate occasions, the same joint is nesthetized by using local anesthetics with different durations f action. If patients obtained appropriate response with both locks, they were considered a positive. If they obtained apropriate response with lidocaine but not with bupivacaine, hey were considered false-positive, whereas if the response as negative with lidocaine, they were considered negative. Results: The prevalence of lumbar facet joint pain in paients with recurrent pain after various surgical intervention(s) as 16% (95% confidence interval, 9% 23%). The falseositive rate with a single block with lidocaine was 49%.