Bone Structure and Growth Structure of Bone n

Bone Structure and Growth

Structure of Bone n Compact bone ¨ Haversian canals ¨ Osteocytes and lacunae ¨ Canaliculi ¨ Volkmann’s canals

n Spongy (cancellous)bone ¨ Light weight and strong ¨ Trabeculae ¨ Canaliculi ¨ Contain red marrow

Features of a Long Bone

Bone Development & Growth Osteogenesis/ossification n Osteoblast n Osteocyte n

n Intramembranous ossification ¨ Sheet-like connective tissue is replaced with bone ¨ Flat bones of skull and some irregular bones

n Endochondral ossification ¨ Replaces hyaline cartilage with bone ¨ Forms most bones in body ¨ Growth in bone length is created through a similar process

Endochondral Ossification

Bone Growth only occurs at epiphyseal plate n Growth ends in the early 20 s n Bone growth is controlled by growth and sex hormones n Appositional growth continues throughout life n

Functions of the Skeleton Support n Protection n Movement n Storage n Hematopoiesis n

Articulations Any place where two bones meet n Synarthroses n Amphiarthroses n Diarthroses n

Synarthroses n Immovable joints

Amphiarthroses n n Slightly movable joints Bones connected by hyaline cartilage or fibrocartilage

Diarthroses Freely movable joints n Ends of bone covered in hyaline cartilage n Bones separated by a joint cavity n Cavity lined with synovial membrane n Bursae n

Ball and socket joint

Condyloid (condylar) joint

Saddle Joint

Pivot joint

Hinge joint

Gliding (plane) joints