AP 6 Skeletal System Part 3 Bone Structure

31 terms by meason4583 Plus

Create a new folder

Advertisement Upgrade to remove ads

Chapter 6 - Skeletal System Part 3 - Bone Structure

Types of Bone Tissue

Woven Bone, Lamellar Bone - bone remodeling

Woven Bone

Collagen fibers randomly oriented. Formed during fetal development and during fracture repair. for fractures it is laid down to stop blood loss.

Lamellar Bone

Mature bone insheets called lamellae. Fibers oriented in one direction in each layer, but in different directions in different layers for strength. Extremely strong:resistant to bending, twisting, compacting. Osteocytes (w/lacunae) arranged in layers sandwiched between lamellae.

Remodeling

Removing old bone and adding new, woven bone is remodeled into lamellar bone

How Bone is Classified?

Whether woven or lamellar, can be classified according to amount of bone matrix relative to amount of space w/in bone. Spongy bone has less matrix and more space than compact bone.

Spongy Bone

Trabeculae, Periosteum, Marrow

Trabeculae

Interconnecting rods or plates of bone. Like scaffolding. spaces flled w/red & yellow marrow & blood vessels, covered w/endosteum, lines the inner cavities of bones, oriented along stress lines, will reorient if stress changes. Osteoporosis - trabeculae breaks down and more prone to fracture.

Spongy Bone Histology Pic

Spongy Bone Trabeculae Pic

Spongy Bone Perioseum Pic

Spongy Bone Marrow Pic

Compact Bone

denser and has fewer spaces than spongy bone; consist of Central (Haversian) canals, Lamellae, Osteon (Haversian) System, Perforating (Volkmann's) canal

Central (Haversian) Canals

in compact bone - run parallel to long axis and lined w/endosteium and contain blood vessels, nerves and loose connective tissue

Lamellae

in compact bone - concentric, circumferential, interstitial - primarily oriented around blood vessels that enter substance of bone itself

Concentric Lamellae

circular layers of bone matrix that surrounds central canal

Circumferential Lamellae

forms outer surface of compact bone - thin plates that extend around bone.

Interstitial Lamellae

between osteons. Remnants of concentric or circumferential lamellae (osteons) there were partially removed during bone remodeling

Osteon (Haversian) System

in compact bone - consists of single central canal, its contents, associated concentric lamellae and osteocytes. Blood vessel-filled central canal (Haversian canal), Lacunae and canaliculi contain osteocytes and fluid.

What does osteon (haversian) system look like?

Cross section - resembles circular target; 'bulls-eye' is central canal and 40-20 concentric lamellae form rings. Osteocytes located in lacunae etween lamellar rings, and caniliculi radiate between lacunae across lamellae, looking like minute cracks across rings of target.

Perforating (Volkmann's) Canal

in compact bone - perpendicular to long axis and not surrounded by concentric lamellae but pass through it. Both perforating and central canals contain blood vessels. Direct flow of nutrients and waist to and from osteocytes via: interstitial fluid of lacunae and caniculi and from osteocyte to osteocyte by gap junction.

Compact Bone Pic

Compact Bone Osteons Pic

Compact Bone Central Canals Pic

Compact Bone Perforating Canals Pic

Compact Bone Interstitial Lamellae Pic

this is what gets cleaned up in bone repair and remodeling

Osteon Histology Pic

Osteon Pic

Osteon Central Canal Pic

Osteon Canaliculi Pic

Osteon Intersitical Lamella Pic

Osteon Lacunae Pic

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set