A comparison of physical and psychological features of responders and non-responders to cervical facet blocks in chronic whiplash

Abstract

BackgroundCervical facet block (FB) procedures are often used as a diagnostic precursor to radiofrequency neurotomies (RFN) in the management of chronic whiplash associated disorders (WAD). Some individuals will respond to the FB procedures and others will not respond. Such responders and non-responders provided a sample of convenience to question whether there were differences in their physical and psychological features. This information may inform future predictive studies and ultimately the clinical selection of patients for FB procedures.MethodsThis cross-sectional study involved 58 individuals with chronic WAD who responded to cervical FB procedures (WAD_R); 32 who did not respond (WAD_NR) and 30 Healthy Controls (HC)s. Measures included: quantitative sensory tests (pressure; thermal pain thresholds; brachial plexus provocation test); nociceptive flexion reflex (NFR); motor function (cervical range of movement (ROM); activity of the superficial neck flexors during the cranio-cervical flexion test (CCFT). Self-reported measures were gained from the following questionnaires: neuropathic pain (s-LANSS); psychological distress (General Health Questionnaire-28), post-traumatic stress (PDS) and pain catastrophization (PCS). Individuals with chronic whiplash attended the laboratory once the effects of the blocks had abated and symptoms had returned.ResultsFollowing FB procedures, both WAD groups demonstrated generalized hypersensitivity to all sensory tests, decreased neck ROM and increased superficial muscle activity with the CCFT compared to controls (p < 0.05). There were no significant differences between WAD groups (all p > 0.05). Both WAD groups demonstrated psychological distress (GHQ-28; p < 0.05), moderate post-traumatic stress symptoms and pain catastrophization. The WAD_NR group also demonstrated increased medication intake and elevated PCS scores compared to the WAD_R group (p < 0.05).ConclusionsChronic WAD responders and non-responders to FB procedures demonstrate a similar presentation of sensory disturbance, motor dysfunction and psychological distress. Higher levels of pain catastrophization and greater medication intake were the only factors found to differentiate these groups.

Whiplash associated disorders: A prospective investigation of the effects of cervical medial branch radiofrequency neurotomy on sensory, motor and psychological Features

“…The median [range] duration of symptoms post whiplash was 43 [9 -195] months. All participants received initial treatment following the MVC [376]. As previously reported, pain scores (VAS 0-100: mean +/-SD) were stable between t(1) ( …”

“…This may be a reason for ongoing levels of distress. Alternatively the ongoing distress may be related to the 'other' symptoms reported by over 50% of individuals in this study including headaches, shoulder/arm pain, thoracic spine pain and lumbar spine pain [376]. The reverse relationship may also exist, whereby ongoing psychological distress leads to persistent pain and disability [409].…”

“…As previously reported [376], a general intake questionnaire was provided to capture the details of collision related factors, symptoms and demographics of the participants.…”

“…Participants were assessed and completed questionnaires at the following time points: (t1) at a time period when their familiar baseline neck pain was present (when symptoms returned following successful cervical facet joint blockade) [376]; (t2): immediately prior to receiving RFN [400]; t(3)one month following RFN and t(4): 3 months following RFN.…”

“…Consecutive participants were recruited from individuals aged 18-65 years with WAD Grade II [2] of a duration greater than 6 months post motor vehicle collision (MVC) following successful response (greater than 50% of neck pain relief) to cervical facet joint blockade (intra-articular block followed by confirmatory MBB) [376], who subsequently underwent RFN.…”