Effect of intra-articular fracture on articular chondrocytes. A transmission electron microscopic study

Intra-articular fractures involving the subchondral bone were produced surgically in both left and right medial femoral condyles of twenty rabbits. The edges of the fractures on the left side were well approximated, while those on the right side maintained with a gap of 2 mm. Transmission electron microscopic study of the nearby articular cartilages conducted 1, 2, 3, 4 and 5 months after the fracture revealed the following results: 1) The neighbouring articular chondrocytes tended once to assume the configuration of fibroblasts; 2) Those remote from the fracture showed both degeneration and hyperplasia to form clones; 3) Even after the intra-articular fractures were well-healed, degeneration and hyperplasia of the articular chondrocytes nearby the fracture would persist for some time.