title: Ultrastructure of solitary enchondromas.
abstract: Solitary enchondromas obtained from the small bones of the hand were studied with transmission electron microscopy. Three cell types were seen as follows: (1) young looking, active cells with extensive dilated rough endoplasmic reticulum and well defined Golgi and mitochondria; (2) older looking, degenerating cells with dilated rough endoplasmic reticulum, well defined Golgi, glycogen masses, vacuoles containing tropocollagen, lipid and myelin figures; and (3) dying cells showing loss of cell membrane and lysosomal-like bodies. A young chondroblastic cell may try to mature, become a normal chondrocyte that produces normal matrix but it does not succeed and dies. Enchondromal cells are not capable of forming tropocollagen or synthesizing proteoglycans for the matrix.
mesh_terms: D001859:Bone Neoplasms / Q000648:ultrastructure*; D002467:Cell Nucleus / Q000648:ultrastructure; D002812:Chondroma / Q000648:ultrastructure*; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000648:ultrastructure; D006225:Hand; D006801:Humans; D008928:Mitochondria / Q000648:ultrastructure