Journal
RHEUMATOLOGY
Volume 47, Issue 7, Pages 1018-1024Publisher
OXFORD UNIV PRESS
DOI: 10.1093/rheumatology/ken145
Keywords
systemic sclerosis; scleroderma; skin hardness; skin elasticity; skin viscosity; visco elastic ratio; relaxation time; skin score; sensing device; computer-assisted device
Categories
Ask authors/readers for more resources
Objectives. No objective method to measure skin involvement in SSc has been established. We developed a novel method using a computer-linked device to simultaneously quantify physical properties of the skin such as hardness, elasticity and viscosity. Methods. Skin hardness was calculated by measuring the depth of an indenter pressed onto the skin. The Voigt model was used to calculate skin elasticity, viscosity, viscoelastic ratio and relaxation time by analysing the waveform of skin surface behaviour. The results were compared with the modified Rodnan skin score (mRSS) obtained at 17 sites on the bodies of 20 SSc patients and 20 healthy controls. A functional assessment questionnaire was administered to determine how skin hardness represents a patients disability. We also examined intra- and inter-observer variability to determine the reliability of this method. Results. The crude hardness obtained with this device correlated well with the standard hardness specified by the American Society for Testing and Materials (ASTM, r = 0.957). A close relationship between hardness and total mRSS was also observed (r = 0.832). Skin elasticity correlated positively, and relaxation time negatively with mRSS. Functional disability correlated more closely with skin hardness (r = 0.643) than with mRSS (r = 0.517). Intra- and inter-observer variabilities were 7.63 and 19.76, respectively, which were lower than those reported for mRSS. Conclusions. Increases in hardness and elasticity as well as shortening of relaxation time constitute objective characteristics of skin involvement in SSc. The system devised by us proved to be able to assess skin abnormalities of SSc with high reliability.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available