[Ultrasound morphologic criteria in evaluating meniscus changes--an experimental study].

Experimental data and clinical experience with ultrasonography have demonstrated good results in the evaluation of internal derangements of the knee. But the value of ultrasound of the menisci still is controversial. The following investigations compare sonography with histologic results. In a water bath 64 cadaveric menisci were examined with a 5 MHz phased array sector scan. Pathologic conditions like natural or artificial tears, meniscal degeneration and crystal deposition diseases gave different echoes. In cases of vertical meniscal tears, a sharp and bright line-echo is seen on the screen. Due to this consistent reflexion, different types of meniscal tears cannot be differentiated by ultrasound. Severe degrees of meniscal soft tissue degeneration, proven histologically, were shown as hypoechoic areas. Following this experimental results, sonography is a useful modality in the diagnosis of meniscal disorders.