Biomechanical properties of normal tendons, normal palmar aponeuroses, and tissues from patients with Dupuytrenʹs disease subjected to elastase and chondroitinase treatment

Normal tendons, normal palmar aponeuroses and palmar aponeuroses from patients with Dupuytrenʹs disease were subjected to elastase or chondroitinase treatment. Youngʹs modulus was derived from the linear portion of stress-strain graph. It showed the lowest value for the apparently normal palmar aponeuroses and the highest value for tendon samples. Elastase treatment caused an increase of extensibility and a reduction of Youngʹs modulus of normal palmar aponeuroses and tendons, but not of contracture bands. In normal tendons, normal palmar aponeuroses and apparently normal palmar aponeuroses residual strain and hysteresis loop increased significantly as a linear function of the amount of digested elastin. In contrast these biomechanical parameters were not affected significantly in contracture bands. In normal and apparently normal areas incubation with chondroitinase ABC resulted in a significant increase of residual strain and, as opposed to elastase, a decrease of normalized hysteresis loop. In contracture bands, however, these biomechanical parameters remained unchanged.