Journal Article

Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis

Marenzana, Massimo, Das Neves Borges, Patricia, Vincent, Tonia L.

2017

Overview

The degradation of articular cartilage, which characterises osteoarthritis (OA), is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal changes in periarticular bone in murine OA by novel, automated micro-CT methods. OA was induced by destabilisation of the medial meniscus (DMM) in 10-week old male mice and disease assessed cross-sectionally from 1- to 20-weeks post-surgery. A novel approach was developed to automatically segment subchondral bone compartments into plate and trabecular bone in micro-CT scans of tibial epiphyses. Osteophyte volume, as assessed by shape differences using 3D image registration, and by measuring total epiphyseal volume was performed. Significant linear and volumetric structural modifications in subchondral bone compartments and osteophytes were measured from 4-weeks post-surgery and showed progressive changes at all time points; by 20 weeks, medial subchondral bone plate thickness increased by 160±19.5 μm and the medial osteophyte grew by 0.124±0.028 μm3. Excellent agreement was found when automated measurements were compared with manual assessments. Our automated methods for assessing bone changes in murine periarticular bone are rapid, quantitative, and highly accurate, and promise to be a useful tool in future preclinical studies of OA progression and treatment. The current approaches were developed specifically for cross-sectional micro-CT studies but could be applied to longitudinal studies.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Analysis / Animal models / Animals / Arthritis / Arthritis, Experimental - diagnostic imaging / Arthritis, Experimental - pathology / Automation / Biocompatibility / Bioengineering / Biology and Life Sciences / Bone remodeling / Bone surgery / Cancellous bone / Cartilage / Cartilage (articular) / Cartilage diseases / CAT scans / Compartments / Computed tomography / Correlation analysis / Cysts / Datasets / Diagnostic imaging / Epiphyses - diagnostic imaging / Epiphyses - pathology / Epiphysis / Image processing / Image registration / Image segmentation / Imaging, Three-Dimensional - methods / Knee / Longitudinal studies / Male / Medical imaging / Medicine and Health Sciences / Meniscus / Mice / Mice, Inbred C57BL / Osteoarthritis / Osteophyte - diagnostic imaging / Osteophyte - pathology / Osteophytes / Pathogenesis / Physical Sciences / Plates (structural members) / Registration / Research and Analysis Methods / Rheumatology / Risk factors / Scanners / Sclerosis / Studies / Subchondral bone / Surgery / Three dimensional imaging / Tibia - diagnostic imaging / Tibia - pathology / X-Ray Microtomography