Skeletal System & Joints Flashcards
How many bones does the human body have?
206
How are bones grouped?
Axial and appendicular skeleton
What does the axial skeleton consist of?
- Cranium
- Spinal Vertebrae
- Ribs
- Sternum
- Sacrum
- Coccyx
Function of the axial skeleton
Protects internal organs
Function of the appendicular skeleton
Facilitate movement
Name the 5 types of bones
1) Long
2) Short
3) Flat
4) Irregular
5) Sesamoid
Function of flat bones
Protect internal organs such as the brain, heart and lungs
Name the different flat bones
Cranial bones
Scapulae
Sternum
Ribs
Function of long bones
Support the weight of the body and facilitate movement
Name the different long bones
Humerus
Radius & Ulna
Femur
Tibia & Fibula
Metacarpals & metatarsals
What are short bones?
Cube-shaped components of the wrist and ankle joints
Name the different short bones
Carpals (arm)
Tarsals (foot)
Irregular bones vary in?
shape & structure
Name the different irregular bones
Vertebrae
Pelvic bones
Function of sesamoid bones
Reinforce tendons, protecting them from stress & wear
Name the sesamoid bone
Patella
Epiphysis
The rounded end of a long bone
Diaphysis
The shaft of a long bone
Articular cartilage
The articulating surface in freely movable joints.
- smooth
- slippery
- porous
- malleable
- insensitive
- avascular (bloodless)
Periosteum
Dense, fibrous membrane that covers the outer surface of bones. A connective tissue layer that plays a crucial role in the growth, repair and nourishment of bones.
What does Cancellous (spongy) bone consist of and where are they found?
Consists of interwoven beams (trabeculae) of bone in the:
- epiphyses of long bones
- bodies of the vertebrae
- other bones without cavities
What do Compact bones form?
Forms the stout walls of the diaphysis & the thinner outer surface of other bones where there is no articular cartilage (eg flat bones of the skull)
Medullary cavity
The cavity of the diaphysis.
- Red in the young
- Yellow when mature
What is red marrow?
A red, gelatinous substance composed of red & white blood cells in a variety of developmental forms & specialized capillaries enmeshed in reticular tissue.
What is yellow marrow?
Fatty connective tissue that does not produce blood cells
Nutrient artery
The principle artery and major supplier of oxygen & nutrients to the shaft or body of a bone
Endochondral Ossification - bone development
A process by which bones are formed and developed in the skeletal system.
How many steps are there in the endochondral ossification process?
8 steps
At what age does the endochondral process start and end?
Starts at 5 weeks after fertilization and ends at age 12-20 years
3 classifications of joints
1) immovable (synarthroses)
2) partly movable (amphiarthroses)
3) freely movable (synovial joint or diarthroses)
Fibrous joints
- synarthroses (immovable)
- articulating bones connected by fibrous tissue
- structures of the skull
- Teeth in their socket are fixed fibrous joints
Partly movable fibrous joints
Syndesmoses
interosseous ligaments between bones of the forearm or bones of the leg
Cartilaginous joints
- immovable joints seen during growth
- such as growth plates & the joint between the 1st rib and the sternum
Fibrocartilaginous joints
- partly movable fibrocartilaginous joints
Example: intervertebral disc & part of the sacroiliac joint
Sympheses
- partly movable fibrocartilaginous joints
Example: pubic bones (symphysis pubis) & the manubrium and the body of the sternum (sternal angle)
Synovial joints
- freely movable
- articulating bones
- articular cartilage
- synovial membrane
- synovial cavity (fluid)
- joint capsule
- bursa
- collateral ligament
Types of Synovial Joints
- Ball & socket
- Hinge
- Saddle
- Ellipsoid
- Pivot
- Gliding
Ball & socket joints
- hip & shoulder
- movements in all direction are permitted: flexion, extension, adduction, abduction, internal, external rotation and circumduction
Hinge joint
- permits movement in one plane only: flexion/ extension
- ankle
- interphalangeal
- elbow
- knee
Saddle joint
- carpometacarpal joint at the base of the thumb
- permits all motions besides rotation
Ellipsoid joint
- reduced ball & socket configuration in which significant rotation is largely excluded
- the bicondylar knee, temporomandilibular & radiocarpal (wrist) joints
Pivot joint
- a ring of bone around a peg; ex the C1 vertebra rotates about the dens of C2
- a rounded numeral capitulum on which the radial head pivots (rotates)
Gliding joints
- ex the facet joints of the vertebrae, the acromioclavicular, intercarpal & intertarsal joints generally have flat articulating surfaces
Mention the 6 Cranial Bones of the skull
- Occipital
- Parietal
- Frontal
- Temporal
- Ethmoid
- Sphenoid
Mention the 8 Facial Bones of the skull
- Nasal
- Vomer
- Lacrimal
- Zygomatic
- Palatine
- Maxilla
- Mandible
- Inferior Nasal Concha
What do two temporomandibular joints form?
Craniomandibular Joint
What forms the temporomandibular joint?
- Temporal bone
- Mandible
- Condylar process
Mention the 3 different types of joints
- Fibrous joints
- Cartilaginous joints
- Synovial joints
Movement of TMJ
Temporomandibular Joint
- Lateral
- Protrusion
- Retraction
- Elevation
- Depression
What does the appendicular skeleton consist of?
- upper limbs
- lower limbs
- shoulder girdle
- pelvis
Scapula
- medial border
- lateral border
- superior border
- inferior angle
The skeleton
Provides structure & protection as well as facilitates motion
