Inciting Events Associated With Lumbar Facet Joint Pain

BACKGROUND:Low back pain is the leading cause of years lost to disability with approximately 15%–25% of the chronic back pain population suffering from lumbar facet arthropathy. No large-scale study has sought to systematically identify inciting events for lumbar facet arthropathy. The aim of this study is to quantify the proportion of individuals with lumbar facetogenic pain who report a specific precipitating event(s) and to determine if there is a correlation between these events and treatment outcome. METHODS:Institutional electronic medical records were searched based on the current procedural terminology (CPT) codes representing lumbar facet joint radiofrequency ablation for procedures performed between January 2007 and December 2015. All patients had obtained ≥50% pain relief based on 6-hour pain diaries after 1 or more diagnostic facet blocks. A positive outcome was defined as ≥50% pain relief sustained for longer than 3-month after procedure, without additional procedural interventions. RESULTS:One thousand sixty-nine people were included in analysis. In the 52% of individuals who described an inciting event, the most commonly reported causes were falls (11%), motor vehicle collisions (11%), sports-related injuries (11%, of which weightlifting accounted for 62%), nonspine postsurgical injuries (2%), and “other” (17%). Six hundred seventeen (57.7%) individuals experienced ≥50% pain relief sustained for >3 months. Patients whose pain was preceded by an inciting event were more likely to have a positive outcome than those who could not recall a specific precipitating factor (odds ratio, 1.5; confidence interval, 1.02–2.1, P = .01). Another factor associated with outcome was shorter duration of pain (8.1 ± 9.2 vs 9.7 ± 10.1 years, P = .02), with an observed modifier effect of age on outcomes. For a 1-year increase in age, there was a 10% increase in the odds of a positive response. CONCLUSIONS:Inciting events are common in patients diagnosed with lumbar facetogenic pain and may be associated with a positive outcome.