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.