High-Intensity Zone on L-spine MRI: Clinical Relevance and Association with Trauma History

STUDY DESIGN This is a retrospective study. PURPOSE We wanted to investigate the clinical relevance of the lumbar high intensity zone (HIZ) on magnetic resonance imaging (MRI) and the relationship of trauma history to internal disc disruption (IDD). OVERVIEW OF LITERATURE HIZs on lumbar spine (L-spine) MRI have been suggested as a reliable marker of IDD by some authors. The prevalence and type of spinal trauma in IDD have not yet been carefully analyzed. METHODS L-spine MRIs of 737 patients with low back pain with or without associated leg pain were reviewed for the presence of HIZs. HIZs on T2-weighted MR images were determined according to the Aprill and Bogduk criteria. A review of medical records and a telephone interview were performed for further analyses of pain. RESULTS HIZs were found in 117 patients and 153 discs among a total of 737 patients who met the inclusion criteria. Both a medical record review and a telephone interview were possible with 99 patients. Among these, 42 patients had had an episode of trauma. Seventeen of these had a relatively high-energy injury such as a traffic accident or a fall. Regarding back pain, 27 patients complained of typical discogenic back pain. Only 11 patients had both a trauma history and typical discogenic pain and 41 patients (42%) had neither a trauma history nor typical natural pain. CONCLUSIONS Given the low incidence of discogenic pain, a HIZ on an L-spine MRI appears less meaningful than often assumed as a specific marker of IDD. Trauma, such as a traffic accident, seems unlikely to be the main cause of IDD.