KINE 2031 Lecture Notes - Lecture 5: Synchondrosis, Fetal Position, Intertrochanteric Crest

• School: York University
• Department: Kinesiology & Health Science
• Course: KINE 2031
• Professor: Olivier Birot

Document Summary

The skeletal system starts off as hyaline cartilage model of the bone. Osteoblasts do two things on the 12th week of development: (1st primary ossification centre: lay down compact bone on the outside of the cartilage, go towards the diaphysis and start to change the cartilage into spongy bone. Osteoclast from the periosteum and invade the diaphysis and start to breakdown the spongy bone forming a cavity, medullary cavity. this reshapes the inner bone by helping form trabeculae, which help resist compression force. At about time of birth: (secondary ossification centre: osteoblast invades the cartilage at either ends and turns the cartilage into spongy bone. Between the primary and the secondary ossification centre will be a growing zone of cartilage called the epiphyseal cartilage. Epiphyseal cartilage continues to form at the end of long bones while osteoblast covers the cartilage into bone. Bone will stop growing until the primary/secondary ossification centres is converted.