BSC2085L Lesson 3

Subdivisions of Skeleton

Axial Skeleton - skull, vertebrae, ribs

Appendicular Skeleton - limbs, pectoral girdle, and pelvic girdle

STUDY SLIDE 2

Bone markings indicate

-where bones form joints with other bones, muscles, and tendons

-where ligaments attach

-where blood vessels and nerves pass

STUDY SLIDE 4

Bone Classification

Compact Bone - smooth and homogenous

Spongy/Cancellous Bone - has small trabeculae (bars) and lots of space

STUDY SLIDE 6

Four Major Groups of Bones

1) Long bones - longer than they are wide; made mostly of compact bone (example: femur)

2) Short bones - cube-shaped; mostly spongy bone (example: tarsals/carpals)

3) Flat Bones - thin, 2 wafer-like layers of compact bone w/spongy bone in between (example: skull)

4) Irregular Bones - irregular shaped bones (example: vertebrae)

STUDY SLIDES 8, 9, 11, 12, 15, 18, & 22

Long Bone Structure: Epiphysis

End of bone (distal and proximal)

Long Bone Structure: Periosteum

Covers the bone; Sharpey's fiber from this penetrates the bone

Long Bone Structure: Articular Cartilage

Covers epiphyseal surface instead of periosteum

Long Bone Structure: Epiphyseal Plate

Area of hyaline cartilage where longitudinal growth of bones occur (seen as epiphyseal line in adults)

Long Bone Structure: Endosteum

Lines the shaft

Long Bone Structure: Medullary Cavity

Hollow central interior. Contains yellow bone barrow in adults, red bone marrow in infants.

Long Bone Structure: Yellow Bone Marrow

Composed of adipose tissue (fat cells)

Long Bone Structure: Red Bone Marrow

Consists of immature red and white blood cells and stem cells. Used to produce blood cells.

Compact Bone: Osteon (Haversian System)

Central canal and all concentric lamellae with Haversian/central canal in center

Compact Bone: Haversian/Central Canal

Runs along length of bone; carries blood, lymph vessels and nerves

Compact Bone: Canaliculus/Canaliculi

Tiny canals radiating outward from central canal (single canal=canaliculus). They connect the central canal to small chamber in the lamellae called lacunae

Compact Bone: Osteocytes

Mature bone cells found inside lacunae

Compact Bone: Lacunae

Small chambers that 'house' the mature bone cells (osteocytes)

Compact Bone: Perforating/Volkmann's Canals

Canals that run into compact bone and marrow cavity from the periosteum

Bone Disorder: Shin Splints

Dull ache in shin; most causes of shin pain are classified as medial tibial stress syndrome (MTSS) which is pain caused by inflammation of the periosteum (periostitis) and inflammation of the perforating fibers

Contributing Factors to MTSS Include

Mechanical factors (flat feet, inversion of feet with impact exercises)

Skeletal Cartilage: Articular

Covers bone ends of movable joints

Skeletal Cartilage: Costal

Connecting ribs to sternum

Skeletal Cartilage: Laryngeal

Construct the larynx

Skeletal Cartilage: Tracheal & Bronchial

Reinforce passageways of respiratory system

Skeletal Cartilage: Nasal

Supports nose

Skeletal Cartilage: Intervertebral Discs

Cushion bones of spine

Cartilage Types Found in the Skeleton

Hyaline - found in nasal, articular, costal, tracheal/bronchial (air passages); most skeletal cartilages are composed of this type

Elastic - only found in external ear and epiglottis

Fibrocartilage - found in cartilage at knee joint, pubic symphysis, intervertebral