Age-related changes in human cervical, thoracal and lumbar intervertebral disc exhibit a strong intra-individual correlation

Abstract

Introduction: Intervertebral disc (IVD) degeneration is characterized as a multifactorial disease, in which the hereditary background is thought to be of high importance. Accordingly, one would expect all spinal levels (lumbar/cervical/thoracal) to be affected by above-average disc degeneration in genetically predisposed individuals. The aim of this study, therefore, was to analyze the amount of degenerative changes in different spine levels in humans from different ages.

Materials and methods: In detail, the presence, localization and abundance of histomorphological changes in the annulus fibrosus (AF) and nucleus pulposus (NP) in the cervical (C5/C6), thoracic (T2/T3) and lumbar (L2/L3) spine were investigated in complete autopsy IVD specimens (47 individuals) covering a complete age range (0-95 years).

Results: Results indicate that the highest degree of histo-degenerative changes were observed in the NP in all spine levels and showed an age-related expression pattern. With regard to the different spine levels, lumbar disc specimen showed significantly more degenerative changes compared to cervical and thoracic discs, whereas no statistical difference was observed between cervical and thoracic discs. In summary, highest grades of degeneration were observed in lumbar discs (especially in the NP). Intra-individual correlations between the degeneration score in the different levels showed a significant individual concordance.

Conclusions: The intra-individual correlation of degenerative changes in all three examined spine regions further supports the notion that individual, i.e. genetic factors are strong predisposing factor for the development of age-related disc alterations.

Figures

Fig. 1

Interrelation of the outer annulus fibrosus (OA), inner annulus fibrosus (IA) and the nucleus pulposus (NP) HDS in the three different spine regions with regard to the macroscopic grade of disc degeneration (mean ± SEM)

Fig. 2

Histological classification system (HDS) of all patients in regard to outer annulus fibrosus (OA), inner annulus fibrosus (IA), the nucleus pulposus (NP) in the three different spine regions (mean ± SEM)

Fig. 3

Histological classification system (HDS) of all patients in regard to outer annulus fibrosus (OA), inner annulus fibrosus (IA), the nucleus pulposus (NP) in relation to different age groups (mean ± SEM)

Fig. 4

Individual histological classification system (HDS) for every patient with regard to anatomic subcompartment and spinal region