Prevalence and distribution of cartilage and bone damage at metacarpal head in healthy subjects

Objectives: To determine the prevalence and distribution of the ultrasound (US) findings indicating cartilage and bone damage at the metacarpal head (MH) in a group of healthy subjects (HS), and their association with the clinical and US data. We also aimed to provide standard reference values of cartilage thickness. Methods: US scans of the dorsal aspect of the metacarpophalangeal joints (MCPj) from 2nd to 5th finger of both hands were performed in 179 HS. The presence of cartilage damage, osteophytes and bone erosions was recorded. Results: Cartilage damage, osteophytes and bone erosions were found in at least one MCPj in 30 (16.8%), 17 (9.5%) and 4 (2.2%) out of 179 HS, respectively. Signs of cartilage damage were found in 91 out of 1432 MHs (6.4%). Blurring of the chondrosynovial margin, minimal and severe thinning were detected in 73.7%, 26.3% and 0% of the 91 MHs, respectively. Osteophytes and bone erosions were found in 31 (2.2%) and in 4 (0.3%) MCPjs. The thickness of the MH cartilage ranged between 0.41 and 1.10 mm in males and between 0.36 and 1.03 mm in females. A significant association was found between cartilage thickness and age (r=-0.33, p<0.001), sex (rpb=0.42, p<0.001), height (r=0.39, p<0.001) and osteophytes in the same joint (v=-0.54, p<0.001) and between working condition and osteophytes (v=0.31, p=0.021). Conclusions: This cross-sectional study reports the prevalence of US findings of joint damage in a large cohort of HS. Moreover, standard reference values of the MH cartilage thickness in HS are provided.