Can proteoglycan change in articular cartilage be detected by ultrasound evaluation?

Abstract

This paper assesses the capacity of high-frequency ultrasonic waves for detecting changes in the proteoglycan (PG) content of articular cartilage. 26 cartilage-on-bone samples were exposed to ultrasonic waves via an ultrasound transducer at a frequency of 20 MHz Histology and ImageJ processing were conducted to determine the PG content of the specimen. The ratios of the reflected signals from both the surface and the osteochondral junction (OCJ) were determined from the experimental data. The initial results show an inconsistency in the capacity of ultrasound to distinguish samples with severe proteoglycan loss (i.e. >90% PG loss) from the normal intact sample. This lack of clear distinction was also demonstrated for samples with less than 60% depletion, while there is a clear differentiation between the normal intact sample and those with 55-70% PG loss. © RILEM 2013.