Functions of the skeletal system
Protection of internal organs
Provide bony attachments for muscles and ligaments
Present rigid levers to allow functional movement of the body and its
separate parts
Store mineral and marrow elements for forming new blood cells
organic matrix of bone
Collagen fibers (strength and flexibility)
Ground substance (surrounds bone cells) Osteoblasts
Osteocytes
Osteoblasts
Inorganic mineral content
Mineral salts (calcium and phosphate)
Hard, rigid structure
,Reservoir for calcium and phosphorus
Osteon (Haversion system)
Basic unit of bone
Haversion canals allow nutrients from blood vessels to reach the osteocytes
Osteoblasts
Lay down bone
Responsible for bone growth and repair
Estrogen secretion helps regulate
Osteoclasts
Bone resorption
,Tearing down the old or excess bone
Cancellous bone (trabecular)
Spongy
Thin plates
Laid down in response to stress
Accomodates loads
Compact bone (cortical)
Resistant to compression
Dense in structure
Periosteum
Vascular
Inner layer contains
osteoblasts
Covers the entire bone except for the ends
, long bone
Wolff's law
Bone is laid down where it is needed and resorbed where it is not needed
Why is this important?
Immobilized bone or persons on bedrest are not subject to stress
Bone-resorbing activity
increases (osteoclasts)
Increased risk for fractures
Increased risk for falls
Geriatric Considerations
Protection of internal organs
Provide bony attachments for muscles and ligaments
Present rigid levers to allow functional movement of the body and its
separate parts
Store mineral and marrow elements for forming new blood cells
organic matrix of bone
Collagen fibers (strength and flexibility)
Ground substance (surrounds bone cells) Osteoblasts
Osteocytes
Osteoblasts
Inorganic mineral content
Mineral salts (calcium and phosphate)
Hard, rigid structure
,Reservoir for calcium and phosphorus
Osteon (Haversion system)
Basic unit of bone
Haversion canals allow nutrients from blood vessels to reach the osteocytes
Osteoblasts
Lay down bone
Responsible for bone growth and repair
Estrogen secretion helps regulate
Osteoclasts
Bone resorption
,Tearing down the old or excess bone
Cancellous bone (trabecular)
Spongy
Thin plates
Laid down in response to stress
Accomodates loads
Compact bone (cortical)
Resistant to compression
Dense in structure
Periosteum
Vascular
Inner layer contains
osteoblasts
Covers the entire bone except for the ends
, long bone
Wolff's law
Bone is laid down where it is needed and resorbed where it is not needed
Why is this important?
Immobilized bone or persons on bedrest are not subject to stress
Bone-resorbing activity
increases (osteoclasts)
Increased risk for fractures
Increased risk for falls
Geriatric Considerations
