The prevalence of chronic cervical zygapophysial joint pain after whiplash.

STUDY DESIGN A survey of the prevalence of cervical zygapophysial joint pain was conducted. OBJECTIVES To determine the prevalence of cervical zygapophysial joint pain in patients with chronic neck pain after whiplash. SUMMARY OF BACKGROUND DATA In a significant proportion of patients with whiplash, chronic, refractory neck pain develops. Provisional data suggest many of these patients have zygapophysial joint pain, but the diagnosis has been established by single, uncontrolled diagnostic blocks. METHODS Fifty consecutive, referred patients with chronic neck pain after whiplash injury were studied using double-blind, controlled, diagnostic blocks of the cervical zygapophysial joints. On separate occasions, the joint was blocked with either lignocaine or bupivacaine in random order. RESULTS A positive diagnosis was made only if both blocks relieved the patient's pain and bupivacaine provided longer relief. Painful joints were identified in 54% of the patients (95% confidence interval, 40% to 68%). CONCLUSION In this population, cervical zygapophysial joint pain was the most common source of chronic neck pain after whiplash.