THE PREVALENCE OF DEGENERATIVE DISC DISEASE IN PATIENTS WITH SEVERE SPINAL TRAUMA.

Abstract

Background: It is very difficult to ascertain how much of the degeneration seen in a post-traumatic spine was due to pre-existing disease and how much was due to the trauma. The aim of the current study was to determine the prevalence of pre-existing disc degeneration on MRI in a region of the spine injured by spinal trauma.

Methods: Prospective whole spine MRI study in 118 patients with spinal trauma. One hundred and eighteen consecutive patients (79M:39F, mean age 36years, range 13 – 90 yrs) admitted to our spinal unit for treatment of their acute spinal trauma were investigated with whole spine magnetic resonance imaging (MRI). Whole spine MRI was already the standard protocol for all patients admitted with spinal trauma to rule out co-existing pathology and multiple spinal fractures¹. Patient data, including age, sex, and mechanism of injury was recorded prospectively onto a spinal injury database. We divided the spine into cervical (C1–C7), thoracic (T1–T12), and lumbosacral (L1–S1) regions. For the purpose of this study we documented the presence or absence of pre-existing degenerative disc disease in all regions of the spine. Of particular interest was any pre-existing degenerative disc disease in the region affected by the spinal trauma. The number of spinal levels affected by pre-existing disc disease within each region was also detailed.

Results: The two most common mechanisms of injury were flexion-compression (68 patients) and flexion-distraction (24 patients). Seventy-one of the patients sustained burst fractures and the vast majority of these were in the thoracolumbar region. Thirty-seven patients (31%) had degenerative disc disease in the same region of the spine that was injured in the spinal trauma. Seven patients had pre-existing cervical degeneration in the presence of cervical spine trauma and thirty had pre-existing lumbosacral degeneration in patients that had lumbosacral trauma. Twenty four patients (20%) had more than one level of degenerative change within the same region as their spinal trauma. Eighteen patients (15%) had degeneration in a different region of the spine to the one that was injured.

Conclusion: Thirty one percent of the patients in our study had pre-existing degenerative disc disease in the same region as their spinal trauma despite the average age of our patients being only 36yrs. This has important medicolegal implications because it means that a large % of patients who sustain spinal trauma have pre-existing degenerative changes which are not the result of their injury.