|
KMID : 0376219850220030451
|
|
Chonnam Medical Journal
1985 Volume.22 No. 3 p.451 ~ p.467
|
|
|
Ultrastructure on Histogenesis of the Synovial Joints in Human Fetuses
|
|
|
|
|
Abstract
|
|
|
The development of the metacarpophalangeal joint was studied by electron microscope in human fetuses ranging from 20mm to 100mm crown rump length.
Homogenous interzone in the joint was composed of a single cell type characterized by a large nucleus and a sparse cytoplasm. The cells contained a large number of free ribosome’s with few endoplasmic reticulum and mitochondria. Interzone differentiated into three-layered interzone with two chondrogenous layers and an intermediate layer. In the early developmental stage, the intermediate layer of interzone consisted of a zone which was 3´4 elongated cells thick, but in later phase the cells were converted into chondroblasts and incorporated in the chondrogenous layer. The primitive joint space was first seen in the three-layered interzone as a narrow cleft around the periphery. The cleft contained small amounts of collagen, thin cytoplasmic processes extending from lining cell, and electron dense materials. This dense materials were also present in the intercellular spaces of the chondrogenous layers of the articular mesenchyme. No degenerative phenomena of the intermediate layer of interzone were noticed.
This investigation revealed that formation of the joint cavity starts at periphery in the joints after the intermediate layer of the interzone has become incorporated in the two chondrogenous layers of the interzone.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|