Skeletal System Flashcards
What structures make up the axial skeleton?
Skull, ossicles (inner ear), hyoid bone, rib cage, vertebral column
What structures make up the appendicular skeleton?
Shoulder girdle, arm, hand, pelvic girdle, leg, foot
Functions of the Skeletal System
- Support
- Storage of minerals
- Blood cell production
- Leverage
- Protection
What kind of tissue is osseous tissue?
A supporting connective tissue
What are the three components in mature bone?
- Matrix of bone consists of calcium phosphate (mineral deposits)
- Collagen fibers
- Bone cells
What are the cells of mature bone? (5)
- Osteocytes
- Osteoblasts
- Osteoprogenitor cells
- Osteoclasts
What are osteocytes?
Mature bone cells
What are osteoblasts?
Young bone cells- build up bone
What are osteoprogenitor cells?
Bone stem cells- bone development, growth and repair
What are osteoclasts?
Break down bone (prevent bone from becoming overly dense)
In healthy bone remodeling and growth, there needs to be a good balance between the activity of what two bone cell types?
Osteoblasts (build up) and osteoclasts (break down)
Is bone vascularized?
Yes. Blood vessels travel through central canals in compact bone.
Define terms:
- Osteon
- Canaliculi
- Lacunae
Osteon: Basic structural unit of compact bone. Cylindrical structure that runs parallel to the long axis of the bone.
Canaliculi: Canals connecting lacunae to each other
Lacunae: Cavities arranged in concentric rings around the central canal, osteocytes in here.
Intraosseous (IO) circulatory access?
Device used to infuse fluid, blood, and medications into the bone directly
ID parts of a femur.
- Articular surface of head of femur
- Trabeculae of spongy bone
- Cortex
- Medullary cavity
- Compact bone
What is compact bone and where is it found?
Dense bone or cortical bone. Outer shell, found in the shafts of long bones (diaphysis)
What is spongy bone and where is it found?
Trabecular or cancellous bone. Found near the ends of long bones (epiphysis), deeper.
What are functional differences between compact and spongy bone (how do they conduct stress)?
Compact bone conducts stress from one end of the long bone to the other end of the long bone. Spongy bone is able to resist stresses applied from many different directions.
What is the periosteum?
Outer surface of the bone.
What are the two layers of the periosteum?
Fibrous layer (outermost layer) and osteogenic layer.
What does the periosteum link to?
Tendons, ligaments, joint capsules etc.
What is the purpose of the endosteum?
Bone cells are here to function during growth and remodeling. Osteoprogenitor cells are here, actively involved in growth and repair. Inner surface of the bone.
Describe the structure of a long bone from top to bottom.
Epiphysis
Metaphysis
Diaphysis (shaft)
Metaphysis
Epiphysis
What is the epiphysis?
Rounded, expanded ends of bone, primarily composed of spongy bone. Yellow marrow here.
What is the metaphysis?
Portion of bone in between epiphysis and diaphysis. Has the epiphyseal plate, cartilage responsible for bone growth.
What happens if the metaphysis is damaged?
Possible stunted growth at the bones.
What is the diaphysis?
Long, tubular shaft of bone, composed primarily of compact bone, w which is dense and strong. Medullary cavity is located within the diaphysis. Hollow space, filled with red marrow. Red marrow is responsible for blood cell production.
Where is red marrow?
Diaphysis of bones in the medullary cavity.
What type of marrow produces blood cells?
Red marrow.
What are the 7 types of bone?
- Sutural
- Pneumatized
- Flat
- Long
- Sesamoid
- Short
- Irregular
Sutural bones
Sutural (Wormian) bones are small, flat, oddly shaped bones found between the flat bones of the skull along the sutures. They develop from separate centers of ossification. Not everyone has these.
Pneumatized bones
Pneumatized bones are bones that are hollow or contain numerous air pockets, such as the ethmoid bone, which makes up a part of the nasal cavity. Primarily in skull.
Flat bones
Flat bones have thin, roughly parallel surfaces of compact bone. In structure, a flat bone resembles a spongy bone sandwich, such bones are strong but relatively light. Flat bones form the roof of the skull, the sternum, the ribs, and the scapulae. They protect underlying soft tissues and have an extensive surface area for the attachment of skeletal muscles. Special terms are used when describing the flat bones of the skill, such as the parietal bones. Their relatively thick layers of compact bone are called the internal and external tables, and the layer of spongy bone between the tables is called the diploid. Bones protecting skull, most of the thoracic bony wall (rib cage), scapulae.
Long bones
Long bones are relatively long and slender. They have a diaphysis, two metaphyses, two epiphyses, and a medullary (marrow) cavity. Long bones are found in the upper and lower limbs. Examples include the humerus, radius, ulna, femur, tibia, and fibula.
Sesamoid bones
Sesamoid bones are usually small, round, and flat. They develop inside tendons and are most often encountered near joints at the knee, the hands, and the feet. Few individuals have sesamoid bones at every location possible, but everyone has sesamoid patellae, or kneecaps.
Short bones
Short bones are boxlike in appearance. Their external surfaces are covered by compact bone, but the interior contains spongy bone. Examples of short bones include the carpal bones (wrists) and tarsal bones (ankles).
Irregular bones
Irregular bones have complex shapes with short, flat, notched, or ridged surfaces. Their internal structure is equally varied. The vertebrae that form the spinal column and several bones in the skull are examples of irregular bones. Vertebrae, and complex bones of the skull like the sphenoid and ethmoid bones.
What are joints and what is their function?
Bones are designed for support and mobility, movements are restricted to joints. Joints (articulations) are junctions between two or more bones. Bones may be in direct contact or separated by:
- fibrous tissue, cartilage, or fluid
What is a synarthrosis?
Immovable Joint
List the synarthosis joints.
Suture (in skull)
Synchondrosis (connecting point between breastbone and rib)
Gomphosis (connecting point between jaw and teeth)
Synostosis (connecting skull)
What are amphiarthoses?
Slightly movable joints.
List the amphiarthroses joints.
Syndesmosis (between tibia and fibula in leg, radius and ulna in the forearm)
Symphysis (where the pelvic bones join)
What are diarthroses?
Freely movable synovial joints.
List the diarthroses joints.
Elbow, shoulder, wrist, hip, knee
What are the components of freely movable synovial joints?
- A joint capsule
- The presence of articular cartilages
- A joint cavity filled with synovial fluid
- A synovial membrane
- Accessory structures (cartilages, ligaments, tendons, bursae, menisci, and fat pads)
- Sensory nerves
- Blood vessels
Is a synarthrosis joint strong? Why/why not?
Yes, because it is fairly immovable.
Is a diarthrosis joint strong? Why/why not?
No, because it is highly movable, this more potential for injury.
What you gain in _______, you lose in _________.
What you gain in _________, you lose in _________.
What you gain in mobility, you lose in stability.
What you gain in stability, you lose in mobility.
What is a dislocation?
A displacement of articulated bones, displaces joint.
What are the three categories of motion within synovial joints (freely moving joints)?
- Angular motion
- Rotation
- Special movements
What are the angular motions?
Abduction
Adduction
Flexion
Extension
Hyperextension
Circumduction
What is abduction/adduction?
Angular motion.
Abduction: moving away from the body. (arm moving away from body)
Adduction: moving toward the body. (arm)
What is flexion?
Angular motion.
Decreases the angle between the bones of the joint (bicep curl).
What is extension?
Angular motion.
Increases the angle between the bones of the joint.
What is hyperextension?
Angular motion.
Extending beyond the normal limits.
What is circumduction?
Angular motion.
Making a circular motion.
What are the rotational movements?
Left and right rotation
Medial (internal) and lateral (external) rotation
Pronation and supination
What is left and right rotation?
Rotational movement.
Moving the head in a “no” manner.
What is medial (internal) and lateral (external) rotation?
Rotational movement.
Rotating the arm outward at the shoulder is a lateral rotation. Rotating the arm inward at the shoulder is a medial rotation.
What is pronation and supination?
Rotational movement.
The hand in the anatomical position is in the supinated position. The hand rotated so the palm faces posterior or even downward is the pronated position.
What are the special movements?
Inversion/eversion
Dorsiflexion/plantar flexion
Lateral flexion
Protraction/retraction
Opposition/reposition
Elevation/depression
What is inversion and eversion?
Special movements.
Eversion, ankle rotates out and foot is to the side of the body. Inversion moves foot inward to the body.
What is dorsiflexion and plantar flexion?
Special movements.
Dorsiflexion, toes and foot upward. Plantar flexion, downward.
What is lateral flexion?
Special movements.
Head tilted to right or left side.
What is protrusion and retrusion?
Special movements.
Jaw out, jaw in.
What is depression and elevation?
Special movements.
Jaw down, jaw up.
