Assessment and validation of prognostic models for poor functional recovery 12 months after whiplash injury: A multicentre inception cohort study

Abstract

Uncertainty surrounds prognostic factors after whiplash injury. Previously we identified a prognostic model for 6-month pain-related disability in a cohort of 80 participants with acute whiplash. Predictors included initial disability, older age, decreased cold pain thresholds, decreased neck rotation movement, posttraumatic stress symptoms and decreased sympathetic vasoconstriction. The objective of this study was to externally validate this model. In a multicentre inception cohort study, 286 participants with acute whiplash (I, II or III) were assessed at <3 weeks and 12 months after injury. The Neck Disability Index (NDI) was the outcome. Observed and predicted NDI scores were generated using the published equation of the original model. Model discrimination between participants with no or mild disability from those with moderate to severe disability was examined by receiver operating characteristic curves. Initial NDI and cold pain threshold predicted current observed 12-month NDI scores (r(2) = 0.50, 95% confidence interval 0.42 to 0.58). There was a significant site effect, and the estimated marginal mean ± SE of 12-month NDI for Iceland (27.6 ± 1.79%) was higher than the other 3 sites (Melbourne 11.2 ± 5.03%, Canada 16.4 ± 2.36%, Brisbane 16.8 ± 1.17%). After adjusting for site, age and Impact of Events Scale scores regained significance (r(2) = 0.56, 95% confidence interval 0.48 to 0.64). The tested model was not precise in predicting NDI as a continuous variable. However, it found good accuracy to discriminate participants with moderate to severe disability at 12 months (area under the receiver operating characteristic curve 0.89 [95% confidence interval 0.84-0.94], P<.001) which is clinically useful.

The rapid and progressive degeneration of the cervical multifidus in whiplash: A MRI study of fatty infiltration

“…1 Half of all those exposed to a MVC will never fully recover but have milder symptoms, 2 and 25% (~ 1 million) are expected to present with a complex clinical picture including severe-pain-related disability, 3 muscle degeneration, 4,5 sensory and motor disturbances, 6 muscle weakness, 7 and psychological distress. 6 A number of psychosocial factors (e.g., coping, expectations, anxiety and depression) have been identified as being associated with poor functional recovery.…”

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

“…Our finding that lower disability levels are a predictor of success for cervical RFN is not surprising. The presence of higher disability levels (NDI > 28%) in the acute stage of WAD has frequently been shown to predict poor long-term health outcomes following the injury [6,231,421,426,427], with our study demonstrating the complementary finding that lower disability is a predictor of responsiveness to cervical RFN. Our previous results also demonstrated that individuals who did not respond to initial facet joint block injections (prior to undergoing cervical RFN) presented with higher levels of pain catastrophizing [413].…”

“…are these manifestations dependent on, or independent of, a peripheral nociceptive source?). As some of these features (such as cold hyperalgesia or posttraumatic stress symptoms) are prognostic of poor functional recovery [7,147,231], it is important to determine if these features can be reduced with effective treatment of underlying nociception, or if they are self-maintaining due to neuroplastic changes in the central nervous system [56], indicating that other treatments would be required for their management. The tenet of this body of research is that sustained nociceptive input from the periphery (especially in deep pain-generating structures), results in persistence of central hyperexcitability [54], motor dysfunction and psychological distress [225].…”

“…The presence of both mechanical (reduced pressure pain thresholds) and cold hyperalgesia (elevated cold pain thresholds) in individuals with chronic WAD (which is thought to be indicative of the presence of central sensitization [362]) has been shown to be associated with poor response to conservative physiotherapy [186]. Pain catastrophizing is associated with enhanced pain reports, disability [247,248], poor prognosis [398], lower pain threshold/tolerance levels [63] and with poor response to diagnostic facet joint injections [376] in individuals with WAD; whilst posttraumatic stress symptoms (present in approximately 20-30% of individuals with chronic WAD) also predict poor health outcomes in chronic WAD [228,230,231,421]. High levels of pre-procedural pain have also been associated with poor responsiveness to neurotomy involving the sacro-iliac joint [422].…”

Advancements in Imaging Technology: Do They (or Will They) Equate to Advancements in Our Knowledge of Recovery in Whiplash?

“…Accordingly, approximately 50% will not fully recover, 15 of whom approximately 25% will demonstrate a markedly complex set of signs/ symptoms that include severe pain-related disability, 113 changes in the structure of neck muscle, 29,32,34,39 sensory and motor disturbances, 114 muscle weakness, 89,108,115 and psychological distress. 114,116 Though there is evidence to suggest damage to a number of tissues (facet joints and capsules, the intervertebral disc, ligaments, vascular tissues, osseous structures), 21 no definitive structural cause of the wide T T SYNOPSIS: It is generally accepted that up to 50% of those with a whiplash injury following a motor vehicle collision will fail to fully recover.…”