Surface structure of baboon (Papio anubis) hydrated articular cartilage: study of low temperature replicas by transmission electron microscopy.

Platinum/carbon replicas of the natural articular surfaces of the femoral condyles of normal adult baboons (Papio anubis) were made at approximately -130 degrees C. Washed surfaces displayed arrays of approximately 50-200 nm diameter collagen fibers and low parallel ridges approximately 5 micron apart. Untouched surfaces were often obscured by a featureless lamina. The ultrastructure of the bearing surface of baboon articular cartilage resembles that of quadrupeds such as the dog.