Low Pain Catastrophization and Disability Predict Successful Outcome to Radiofrequency Neurotomy in Individuals with Chronic Whiplash.

OBJECTIVES: Physical and psychological symptoms of individuals with chronic whiplash-associated disorders (WAD) are modulated by successful treatment with cervical radiofrequency neurotomy (cRFN). However, not all individuals respond to cRFN, and it is unknown which clinical features predict successful response to cRFN. METHODS: This prospective cohort study investigated 53 individuals with chronic WAD (36 female, 17 male; mean age = 44.7 ± 10.9 (SD) years) who underwent cRFN. Predictor variables measured at baseline (prior to RFN) included self-reported pain (VAS), disability (NDI), post-traumatic stress symptoms (PDS), pain catastrophizing (PCS), and measures of sensory hypersensitivity (pressure and cold pain thresholds). The outcome measure was perceived Global Rating of Change (where scores ≥ 4 were classified as a successful response) 3 months post-cRFN. RESULTS: Univariate logistic regression demonstrated that lower levels of disability and pain catastrophizing were associated with successful response of cRFN (both P < 0.05). Multivariable logistic regression demonstrated that low levels of pain catastrophizing and disability remained significant predictors of a successful response to cRFN (both P < 0.05). CONCLUSIONS: Low levels of pain catastrophizing and disability independently predicted a successful response to cRFN in patients with chronic WAD.

Modulation of Cervical Facet Joint Nociception and Pain Attenuates Physical and Psychological Features of Chronic Whiplash: A Prospective Study.

OBJECTIVE: To investigate changes in clinical (physical and psychological) features of individuals with chronic whiplash-associated disorder who had previously undergone cervical radiofrequency neurotomy at the time point when the effects of radiofrequency neurotomy had dissipated and pain returned. DESIGN: Prospective cohort observational trial of consecutive patients. SETTING: Tertiary spinal intervention centre in Calgary, Alberta, Canada. PATIENTS: A total of 53 consecutive individuals with chronic whiplash-associated disorder. METHODS: Individuals underwent radiofrequency neurotomy and were assessed before radiofrequency neurotomy, at 1 and 3 months postprocedure, and then after the return of pain (approximately 10 months postprocedure). MAIN OUTCOME MEASUREMENTS: Quantitative sensory tests (pressure; thermal pain thresholds; brachial plexus provocation test), nociceptive flexion reflex, and motor function (cervical range of movement; craniocervical flexion test) were measured. Self-reported disability, psychological distress, pain catastrophization, and posttraumatic stress disorder symptoms also were measured. RESULTS: Upon the return of pain after radiofrequency neurotomy, levels of disability increased (P < .0001), and were no different to those before radiofrequency neurotomy (P = .99). There also was a significant deterioration in quantitative sensory testing measures and reduced cervical range of motion after the return of pain (all P < .05); all approaching values were recorded before radiofrequency neurotomy (P > .22). There were no significant changes in pressure hyperalgesia (P > .054) or craniocervical flexion test performance (P > .07) after the return of pain. Psychological distress and pain catastrophizing increased significantly after the return of pain (P < .01), and again were no different than measures taken prior to radiofrequency neurotomy (P > .13). However, there was no difference in number or severity of posttraumatic stress symptoms after the return of pain (P > .30). CONCLUSIONS: Physical and psychological features of chronic whiplash-associated disorder are modulated dynamically with cervical radiofrequency neurotomy. These findings indicate that peripheral nociception is involved in the manifestations of chronic whiplash-associated disorder in this cohort of individuals.