Severe back-ache in young adults may present a difficult clinical problem when the absence of neurological signs results in delayed diagnosis. Fourteen patients, with discographic evidence of posterior annular fissuring are reported. The discrepancy between painful disability and negative radiographic examination including radiculography is stressed. Discography has proved to be the investigation of choice in these patients. This will demonstrate the morphology of the lesion and reproduce the symptomatology in the majority of cases. The clinical implications are discussed.