Pre-surgical quantitative sensory testing and post-surgical pain among adolescents undergoing spinal fusion surgery:...

Pediatric post-surgical pain is common and associated with diminished quality of life and significant medical costs. While quantitative sensory testing (QST) is a promising tool for predicting post-surgical pain in adults, research in youth is lacking. We tested associations between pre-surgical QST indices (pressure and heat pain thresholds, mechanical temporal summation of pain [MTSP], conditioned pain modulation, and cold-pressor painful after-sensations) and average and worst pain severity and pain interference assessed daily during the first week post-hospital discharge (acute outcomes), as well as six-month post-surgical pain intensity and presence of chronic post-surgical pain (CPSP; six-month pain intensity>3/10 and quality-of-life score<74.9). Of 160 enrolled participants, 142 (mean age=14.6 years, 76% female) who completed QST and outcome measures were analyzed. Mean average and worst acute pain severity across the first seven days were 3.5/10 and 5.5/10. Six-month pain intensity was 2.7/10; 30.6% of participants had CPSP. Controlling for sociodemographic and pre-surgical characteristics, higher MTSP (b=0.17, 95% CI=0.02-0.32) and painful after-sensations (b=0.13, 95% CI=0.02-0.23) were associated with greater average acute pain severity. Higher MTSP was also associated with greater worst acute pain severity (b=0.30, 95% CI=0.12-0.47) and six-month pain intensity (b=0.36, 95% CI=0.16-0.55). No QST indices were associated with CPSP. Exploratory analyses revealed that associations were stronger for youth with mild pre-surgical pain. Results suggest QST, particularly MTSP, is a promising pre-surgical marker to identify adolescents who may experience greater post-surgical pain. Future research should evaluate feasibility of pre-surgical bedside QST and QST as a predictor of responsiveness to post-surgical pain management interventions. PERSPECTIVE: Results from this prospective longitudinal study, the largest to date employing preoperative quantitative sensory testing (QST) in adolescents, suggest that pre-surgical QST, particularly mechanical temporal summation of pain, is a promising marker for identifying adolescents at risk for severe acute post-surgical pain.