The Long-term Impact of Whiplash Injuries on Patient Symptoms and the Associated Degenerative Changes Detected Using MRI: A Prospective 20-year Follow-up Study Comparing Patients with Whiplash-associated Disorders with Asymptomatic Subjects

Study Design.A longitudinal, 20-year comparative study of patients with whiplash-associated disorders (WAD).Objective.The aim of this study was to clarify the long-term impact of WAD on patient symptoms and on magnetic resonance imaging (MRI) findings of the cervical spine, in comparison with asymptomatic volunteers.Summary of Background Data.The long-term impact of WAD has not been fully elucidated.Methods.Between 1993 and 1996, we conducted a cross-sectional comparative study of 508 acute WAD patients and 497 asymptomatic volunteers, all of whom underwent MRI on cervical spine and physical examinations. For this 20-year follow-up comparative study, 75 WAD patients and 181 control subjects aged <60years were recruited from the original cohort. The MRI findings, including discs' signal intensities, posterior disc protrusions, anterior dural compressions, spinal cord disc space narrowing, and foraminal stenoses, were evaluated using two to four numerical grades. The results of the WAD patients and control subjects were compared.Results.In this follow-up, the prevalence of shoulder stiffness (72.0% vs. 45.9%), headache (24.0% vs. 12.2%), and arm pain (13.3% vs. 3.9%) were significantly greater in WAD patients than in control subjects. The multiregression analysis revealed that a history of WAD was associated with shoulder stiffness (odds ratio [OR]: 3.36), headache (OR: 2.39), and arm pain (OR: 3.82). Although MRI findings in WAD patients were more degenerated than in control subjects in the initial study, all MRI findings were similar at the 20-year follow-up. There were no significant correlations between clinical cervical symptoms and progression in each MR finding in either group.Conclusion.After 20years, whiplash injuries significantly impacted the residual symptoms of shoulder stiffness, headache, and arm pain when compared with initially asymptomatic volunteers. The progression of degenerative changes in the cervical intervertebral discs after 20years revealed no association with existing whiplash injuries, neither did the residual cervical-related symptoms.Level of Evidence: 3.