. Author manuscript; available in PMC: 2018 May 1.

Published in final edited form as: Connect Tissue Res. 2016 Oct 31;58(3-4):373–385. doi: 10.1080/03008207.2016.1251425

Table 1.

Definitions of Subchondral Bone and Synovium Measures.

Histological measure

Unit

Definition

Ossification width

\frac{Width o f Ossification Area}{Width o f Osteochondral Interface}

Ossification height

\frac{Width o f Ossification Area}{Width o f Osteochondral Interface}

Edema area

μm²

Sum of the Area Covered by Edema

Edema presence

\frac{Number o f 9 Medical Compartment Images Containing Edema}{9}

Epiphyseal trabecular bone area (ETBA)

\frac{Sum o f Area Covered b y Trabecular Bone Between Articlar Cartilage and Epiphyseal plane}{Sum o f Area Covered b y Trabecular Bone + Bone Marrow Voids Articlar Cartilage and Epiphyseal plane}

Trabecular bone area (TBA)

\frac{Sum o f Area Covered b y Trabecular Bone}{Sum o f Area Covered b y Trabecular Bone + Bone Marrow Voids}

Synovial subintimal cell density

\frac{cells}{100 pixel s^{2}}

(\frac{Number o f Cells i n Image}{Image Width \times Image Height}) \times 100

Synovial subintimal cell aspect ratio

Unitless

\frac{Cell Major Axis Length}{Cell Minor Axis Length}

Synovial subintimal cell alignment

% cell population

\frac{Number o f Cells within \pm 3 ° o f Vertical Alignment}{Number o f Cells i n Image}