The pain drawing as an instrument for identifying cervical spine nerve involvement in chronic whiplash-associated disorders

Objective: The aim of the study was to investigate the psychometric properties of a standardized assessment of pain drawing with regard to clinical signs of cervical spine nerve root involvement. Design: This cross-sectional study included data collected in a randomized controlled study. Patients: Two hundred and sixteen patients with chronic (>= 6 months) whiplash-associated disorders, grade 2 or 3, were included in this study. Methods: The validity, sensitivity, and specificity of a standardized pain drawing assessment for determining nerve root involvement were analyzed, compared to the clinical assessment. In addition, we analyzed the interrater reliability with 50 pain drawings. Results: Agreement was poor between the standardized pain drawing assessment and the clinical assessment (kappa = 0.11, 95% CI: -0.03 to 0.20). Sensitivity was high (93%), but specificity was low (19%). Interrater reliability was good (kappa = 0.64, 95% CI: 0.53 to 0.76). Conclusion: The standardized pain drawing assessment of nerve root involvement in chronic whiplash-associated disorders was not in agreement with the clinical assessment. Further research is warranted to optimize the utilization of a pain/discomfort drawing as a supportive instrument for identifying nerve involvement in cervical spinal injuries.