Bone canaliculus endings in the area of the osteocyte lacuna. Electron-microscopic studies.

Light- and electron-microscopic studies were carried out on the bone canaliculi and their endings in the wall fo the osteocyte lacuna. Two types of canalicular endings were distinguished in the lacuna wall. Those of the first type, fairly numerous, are the endings of small diameter, which do not branch off in the immediate proximity of the lacuna. The other type, occurring in twos or threes, are large in diameter and branch off in the close vicinity of the lacuna, invariably possessing two or three processes which run up to the point of branching of the canaliculus. The images obtained made it possible to demonstrate that the collagen fibrils in both types of endings in the lacuna wall are, in principle, arranged in a similar manner. Nonethless, the type of end formation found where the fibrils run along the axis of the lacuna differs from that for the fibrils in a plexus.