Vertebral end-plate (Modic) changes on lumbar spine MRI: correlation with pain reproduction at lumbar discography

Abstract

IntroductionVertebral end-plate (Modic) changes were first described independently by de Roos et al. [9] and Modic et al. [15] as being a feature associated with degenerative intervertebral disc disease. Type I changes consist of reduced signal intensity (SI) in the vertebral end-plates on T1-and increased SI on T2-weighted sequences (Fig. 1). They are associated with fissuring of the cartilaginous end-plate and increased vascularity within the subchondral bone marrow on histological examination. Type II changes consist of increased SI on T1-and either increased SI or isointensity on T2-weighted sequences (Fig. 2). In such cases, biopsy reveals fatty replacement of the marrow [15], which is thought to be the result of marrow ischaemia [9]. Type III changes consist of reduced SI on both T1-and T2-weighted sequences due to subchondral sclerosis ( Fig. 3). Type I changes commonly progress to Type II changes and rarely revert back to normal, whereas Type II changes appear not to change with time [15]. Modic changes are identified in 20-50% of patients, with the incidence increasing with age [9,15]. However, it is not known why some degenerative discs are associated with Modic changes while others are not.Crock [6,7] proposed the concept of "internal disc disruption", suggesting that repeated trauma to the intervertebral disc could result in the production of inflammatory substances within the nucleus pulposus. Diffusion of such toxic chemicals through the vertebral end-plate could then result in a local inflammatory reaction resulting in back pain.Inflammation in the subchondral bone adjacent to the end-plate would result in reduced SI on T1-weighted MRI sequences and increased SI on T2-weighted MRI sequences, equivalent to a Type 1 Modic change. The possiAbstract The vertebral end-plate has been identified as a possible source of discogenic low back pain. MRI demonstrates end-plate (Modic) changes in 20-50% of patients with low back pain. The aim of this study was to investigate the association between Modic changes on MRI and discogenic back pain on lumbar discography. The MRI studies and discograms of 58 patients with a clinical diagnosis of discogenic back pain were reviewed and the presence of a Modic change was correlated with pain reproduction at 152 disc levels. Twenty-three discs with adjacent Modic changes were injected, 21 of which were associated with pain reproduction. However, pain was also reproduced at 69 levels where no Modic change was seen. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for a Modic change as a marker of a painful disc were 23.3%, 96.8%, 91.3% and 46.5% respectively. Modic changes, therefore, appear to be a relatively specific but insensitive sign of a painful lumbar disc in patients with discogenic low back pain.

Modic (endplate) changes in the lumbar spine: bone micro-architecture and remodelling

“…As such, Modic changes might be due to altered mechanical stress, resulting in histological changes, leading to signal intensity changes on MRI, namely the Modic changes. Biochemical causes on the other hand, imply that Modic changes may result from an inflammatory reaction to toxic mediators or infection from the degenerating disc [39]. An intervertebral disc herniation could be the entry point of bacteria into the disc, and the Modic changes could be therefore the result of anaerobic bacteria leading to oedema and inflammation surrounding the extruded intra-vertebral nuclear material [9,40].…”

MRI follow-up of subchondral signal abnormalities in a selected group of chronic low back pain patients

“…We found a similar trend: most (67%) hypointensities seemed to turn into hyperintensities or disappear, while most (65%) hyperintensities persisted or increased. It has been suggested that they may represent different consecutive phases of the degenerative process in the subchondral marrow [3,17]. The importance of the endplate [21,22] and subchondral bone [8] for the integrity of the intervertebral disc has been pointed out.…”

“…Subchondral signal abnormalities have been found to be associated with LBP [2,3,5,11,26], particularly with hypointensities [2,13,23]. Subchondral edema-like hypointensity on T1 weighted image (T1WI), being hyperintense on T2 weighted image (T2WI), has been found in association with vascularized fibrous tissue and with fissuring or disruption in the adjacent end plates [17].…”

Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 6: Discography for patient selection

“…By recreating the patient's pain, proponents of discography argue that it is more sensitive and specific than other imaging modalities, including plain radiographs, myelography, and MRI, which are known to identify both symptomatic and asymptomatic abnormalities. [2][3][4] However, critics question the reliability and specificity of discography since concordant pain has been suggested to originate from nonspine sources and can be reproduced in patients without any prior history of back pain. 5,8,11 A prospective study intended to evaluate the predictive value of provocative discography following lumbar fusion was performed by Carragee et al 7 Lumbar fusions were performed in 32 patients with presumed discogenic pain and a positive discogram (see Table 1).…”