Intracellular "fibrous long spacing" collagen in morbus dupuytren (Dupuytren's contracture).

Fine structural analysis of 21 surgically removed specimens of Morbus Dupuytren (Dupuytren's contracture) in the cells of the proliferative phase revealed spindle-shaped or round, periodic banded structures of 1--1.5 micron size. These intracellular structures are surrounded by trilaminar membranes of 45 A continuous with membranes of the endoplasmic reticulum. The periodic banded structures display a light-dark pattern of 750--900 A and resemble with respect to periodicity and general morphology "fibrous long spacing" collagen. To date, "fibrous long spacing" collagen in human tissue has only been observed in the extracellular space, both in normal and pathologic conditions. Its formal pathogenesis is discussed.