Macroscopic and radiological grading of osteoarthritis correlates inadequately with cartilage height and histologically demonstrable damage to cartilage structure

Abstract

Introduction: The aim of the present study was to investigate different methods for determining osteoarthritis-related (OA) cartilaginous changes.

Materials and methods: Human tibial heads were investigated radiologically, macroscopically and microscopically. The height of the hyaline cartilage was measured with the aid of a computerised digital image analysis system.

Results: The comparison of the different evaluation systems revealed, in part, appreciable variations in severity and produced correlations of r=-0.312-0.673. In none of the methods was a linear correlation between the histomorphometrically measured decrease in cartilage height and the increasing grade of OA evident.

Discussion: The microscopic scores are superior, since they provide the most precise description of cartilaginous structure. The variation in cartilage height with increasing OA is not a linear process; measurement of the cartilage height alone is not a valid parameter for determining the grade of OA.