Cartilage damage in the metacarpophalangeal (MCP) joints is common among patients with rheumatoid arthritis (RA) and hand osteoarthritis (OA), according to results published in Rheumatology. The results indicated that the second and third MCP joints were the most damaged.
The study included participants with RA (n=52) and participants with hand OA (n=34). The researchers used ultrasound to examine metacarpal head cartilage from the second to fifth finger of both hands. A total of 414 MCP joints were scanned in RA participants and 266 MCP joints for participants with OA.
The researchers performed qualitative assessments using a previously-described scoring system for cartilage damage, analyzing the prevalence and distribution of damage. They used multivariable regression analysis to determine the predictive value of age, gender, body mass index, disease duration, and the presence of rheumatoid factor and anti-cyclic citrullinated peptide antibodies for cartilage damage.
The results indicated that the metacarpal head cartilage was positive for damage in 35.7% (n=148) of MCP joints in RA and 43.6% (n=116) of MCP joints in participants with OA.
Among participants with RA, the most frequently-affected areas were the hyaline cartilage of the II and III metacarpal heads (bilaterally). Among participants with OA, cartilage damage had a more homogenous distribution in all MCP joints.
After performing multivariate regression analysis, the researchers found that age and disease duration were independent predictors of cartilage damage in RA.
“To our knowledge, this study is the first to provide US data regarding the prevalence and distribution of metacarpal head cartilage damage in patients with RA and hand OA using a linear probe with a frequency reaching 22 MHz,” the researchers wrote.
Hurnakova J, Filippucci E, Cipolletta E, et al. Prevalence and distribution of cartilage damage at the metacarpal head level in rheumatoid arthritis and osteoarthritis: an ultrasound study [published online January 25, 2019]. Rheumatology. doi:10.1093/rheumatology/key443