Abstract

OBJECTIVE:

To investigate whether living human articular cartilage can be evaluated quantitatively by means of a new diagnostic technique that introduces an ultrasonic probe into the knee joint under arthroscopy and then analyzes the A-mode echogram by means of wavelet transformation.

DESIGN:

Intact and injured sites of living human articular cartilage were evaluated under arthroscopy. The maximum magnitude and the echo duration (defined as the length of time that included 95% of echo signal) were selected as the quantitative indices on the wavelet map.

BACKGROUND:

Quantitative evaluation of articular cartilage in situ has the potential to contribute to our understanding of cartilage breakdown and to the effectiveness of cartilage regeneration. However, a reliable method of quantitative cartilage evaluation has yet to be developed for clinical use.

METHODS:

Living human articular cartilage was analyzed using an ultrasonic probe under arthroscopy and the cartilage characteristics on the echo duration-maximum magnitude graph were examined.

RESULTS:

Unlike the L-shape distribution of human cadaver cartilage data, the distribution of the living human articular cartilage data showed a smooth curve with a steep initial gradient that flattens gradually at the highest value of echo duration on the echo duration-maximum magnitude graph.

CONCLUSIONS:

The present study suggests a new quantitative evaluation system for articular cartilage with clinical potential.