Premium
Three dimensional mesoscale analysis of translamellar cross‐bridge morphologies in the annulus fibrosus using optical coherence tomography
Author(s) -
Han Sang Kuy,
Chen ChaoWei,
Wierwille Jerry,
Chen Yu,
Hsieh Adam H.
Publication year - 2015
Publication title -
journal of orthopaedic research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.041
H-Index - 155
eISSN - 1554-527X
pISSN - 0736-0266
DOI - 10.1002/jor.22778
Subject(s) - optical coherence tomography , lamellar structure , annulus (botany) , bridge (graph theory) , materials science , anatomy , physics , optics , composite material , biology
The defining characteristic of the annulus fibrosus (AF) of the intervertebral disc (IVD) has long been the lamellar structures that consist of highly ordered collagen fibers arranged in alternating oblique angles from one layer to the next. However, a series of recent histologic studies have demonstrated that AF lamellae contain elastin‐ and type VI collagen‐rich secondary “cross‐bridge” structures across lamellae. In this study, we use optical coherence tomography (OCT) to elucidate the three‐dimensional (3‐D) morphologies of these translamellar cross‐bridges in AF tissues. Mesoscale volumetric images by OCT revealed a 3‐D network of heterogeneously distributed cross‐bridges. The results of this study confirm the translamellar cross‐bridge is identifiable as a distinguishable structure, which lies in the interbundle space of adjacent lamellae and crisscrosses multiple lamellae in the radial direction. In contrast to previously proposed models extrapolated from 2–D sections, results from this current study show that translamellar cross‐bridges exist as a complex, interconnected network. We also found much greater variation in lengths of cross‐bridges within the interbundle space of lamellae (0.8–1.4 mm from the current study versus 0.3–0.6 mm from 2–D sections). OCT‐based 3–D morphology of translamellar cross‐bridge provides novel insight into the AF structure. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:???–???, 2015.