Evaluation of Disc and Endplate Degeneration in AO Type A Fractures Using Magnetic Resonance Imaging Analysis

Abstract

Disc degeneration following trauma has been the focus of several investigations, while vertebral endplate changes have received comparatively less attention. The main aim of the study is to radiologically evaluate the prevalence of degree of degeneration of the adjacent discs and endplates following AO type A thoracolumbar fractures. We retrospectively reviewed 25 patients with AO type A injury (50 discs, and 150 endplates). The type of disc lesion adjacent to the fractured vertebra was classified based on Pfirrmann's and Oner's classifications, immediately after trauma and at 1-year follow-up. The endplate defects were assessed using the endplate scoring system (TEPS - grade 1 to 6) in T1 weighted images. The kyphosis angle and the vertebral body height were also measured. The study population consisted of 18 males (72%) and 7 females (28%) with a mean age of 38.9 ±11.3 years. Overall, 28% of fractures were type A1, 4% were type A2, 24 % were type A3 and 44% were type A4. On statistical analysis, there was a significant change in the degree of degeneration in the cranial adjacent disc based on both Oner (p=0.004) and Pfirrmann (p=0.001) classification at the end of 1-year. The morphological changes at the cranial adjacent discs at 1-year follow-up showed a strong positive correlation with superior endplate degeneration. The present study indicates that endplate fractures of vertebrae in patients with thoracolumbar burst fractures may cause disc degeneration, especially at the cranial endplate.