The site-specific associations between the meniscus changes and the osteophyte formations in early-stage knee osteoarthritis

Abstract

surface was fit (least squares) to the AC surface data points; 2. The bicubic surface was subtracted from the AC surface, resulting in a surface that was assessed by a standard roughness analysis method, R q (Root Mean Square surface height; See ISO 25178). Finally the OARSI grading reference was obtained from Safranin-O stained sections. Results: The developed algorithm successfully segmented the AC surface of the mCT volumes (Fig 2). In mCT, the surface of sample 1 appears to be smooth with minor roughness (Fig 2a, black arrows), barely visible in histology. In addition to roughness, fissures (Samples 2-5; Fig 2b-e, yellow arrows; OARSI grade 3.5-4.5), erosion (Samples 3-5; Fig 2c-d, blue arrows; OARSI grade 4-4.5) and mid-zone excavation (Sample 5;