Anatomical Terminology & the Skeletal System Flashcards
What are the 5 primary functions of the skeletal system?
- Support: provides structural support for the entire body; individual bones or groups of bones provide a framework for the attachment of soft tissue and organs.
- Storage of minerals and lipids: Minerals are inorganic ions that contribute to the osmotic concentration of body fluids. E.g. the calcium salts of bone are a valuable mineral reserve that maintains normal concentrations of calcium and phosphate ions in the body fluids. Yellow bone marrow stores lipids for energy.
- Blood Cell Production: Blood cells are produced in red bone marrow, which fills the internal cavities of many bones..
- Protection: Skeletal structures surround many soft tissues and organs; E.g. ribs + heart & lungs, Skull + brain.
- Leverage: Many bones function as levers that can change the magnitude and direction of the forces generated by skeletal muscles.
What are the two skeletal systems? (1)
- Axial Skeleton : 80 Bones
Skull and associated bones (29)
- Skull - Cranium (8) + Face (14)
- Associated bones - Auditory ossicles (6) + Hybrid (1)
Thoracic Cage (25)
- Sternum - (1)
- Ribs - (24)
Vertebral Column (26)
- Vertebrae - (24)
- Sacrum - (1)
- Coccyx - (1)
What are the two skeletal systems? (2)
- Appendicular Skeleton: 126 Bones
Pectoral girdles (4)
- Clavicle (2)
- Scapula (2)
Upper Limbs (60)
- Humerus (2)
- Radius (2)
- Ulna (2)
- Carpel bones (16)
- Metacarpal bones (10)
- Phalanges (28)
Pelvic girdle (2) - Hip bone (2)
Lower limbs (60)
- Femur (2)
- Patella (2)
- Tibia (2)
- Fibula (2)
- Tarsal bones (14)
- Metatarsal bones (10)
- Phalanges (28)
What are the functions of the Axial and Appendicular skeleton?
Axial = (skull, ribcage, vertebral column) Support, protection of organs, muscle attachment
Appendicular = (upper and lower limbs) Movement and muscle attachment
What are the different classifications of bone shape? (1)
- Sutural bone (wormain bone)
Small, flat, irregularly shaped bones between the flat bones of the skills. There are individual variations in the number, shape, and position of the sutural bones.
What are the different classifications of bone shape? (2)
- Flat bones
Thin, parallel surfaces. Flat bones form the roof of the skull, the sternum, the ribs, and the scapulae. They provide protection for underlying soft tissues and offer an extensive surface area for the attachment of skeletal muscles.
What are the different classifications of bone shape? (3)
- Irregular bones
Have complex shapes with short, flat, notched or ridged surfaces.
E.g.
- vertebrae that form the spinal column
- bones of the pelvis
- several bones in the skull
What are the different classifications of bone shape? (4)
- Long bones
Relatively long and slender. Located in the arm, forearm, thigh and toes. The femur, the long bone of the thigh, is the largest and heaviest bone in the body.
What are the different classifications of bone shape? (5)
Short Bones:
boxlike in appearance, with approximately equal dimensions.
E.g. carpal bones (wrists) and tarsal bones (ankles)
What are the different classifications of bone shape? (6)
Sesamoid Bones:
Small, flat and shaped somewhat like a sesame seed (except for the patella = knee cap). They develop inside tendons and are most often encountered near joints at the knee, the hands, and the feet.
Few individuals have a sesamoid bone in every possible location but everyone has a sesamoid patellae/kneecap
Gross Anatomy: What’s Hyaline cartilage?
Cartilage covering the ends of the bones, stops them rubbing together and absorbs shock.
Gross Anatomy: What’s Epiphysis?
The ‘head’ of the bone.
Gross Anatomy: What’s cancellous bone?
Spongy bone that stores the red bone marrow; where blood cells are made
Gross Anatomy: What’s the Epiphyseal plate?
The area where bones grow in length
Gross Anatomy: What’s the Diaphysis
The bone shaft
Gross Anatomy: What’s Compact bone?
Hard, dense bone. It gives strength to the hollow part of the bone
Gross Anatomy: What’s the Periosteum?
It’s a protective layer where there is no hyaline cartilage. Ligaments and tendons attach to the periosteum
Gross Anatomy: What’s the Medullary cavity/marrow cavity?
It contains bone marrow
Synovial joint movements (angular): What is Flexion, Extension and hyperextension?
Flexion: Bending the limbs at a joint - a movement in the anterior-posterior plane that decreases the angle between articulating bones.
Extension: Straightening limbs at a joint. Occurs in the same plane, but it increases the angle between articulating bones.
Hyperextension: Extension past the anatomical position. When you hyperextend your neck, you can gaze at the ceiling. Ligaments, bony processes or soft tissues prevent hyperetension of many joints, including the elbow and knee
Synovial joint movements (angular): What is Abduction and Adduction?
Abduction: The movement away from the longitudinal axis of the body in the frontal plane. E.g. swinging the upper limb to the side. Moving back to the anatomical position is adduction.
Adduction: Moving a limb back to the anatomical position.
Abduction and adduction always refers to the appendicular skeleton, not the axial.
Synovial joint movements (angular): What is Circumduction?
Moving your arm in a loop is circumduction, as when you draw a large circle on a whiteboard.
Synovial joint movements (angular): What is Rotation?
based on a person in the anatomical position.
Rotation of the head may involve left or right rotation.
Limb rotation is described in reference to the longitudinal axis of the trunk.
Medial rotation (internal or inward rotation), the anterior surface of a limb turns toward the long axis of the trunk.
Synovial joint movements (angular): What is pronation?
Turning of the wrist and hand from facing front to palm facing back.
Directional References (anterior view): What is Superior and Inferior?
Superior: Above; at a higher level (in the human body, towards the head)
Inferior: Below; at a lower level; towards the feet
Directional References: What is Anterior and Posterior?
Anterior/ventral: The front surface. Ventral means the belly side.
Posterior/Dorsal: The back surface. Dorsal means the back.
Directional References (Anterior): What is Lateral and Medial?
Lateral: Away from the midline
Medial: Toward the midline
Directional References (Anterior): What is Proximal and Distal?
Proximal: Towards the point of attachment of a limb to the trunk. (The shoulder is proximal to the wrist).
Distal: Away from the point of attachment of a limb to the trunk. (The fingers are distal to the wrist).
Direction References: What is Superficial and Deep?
Superficial: At, near, or relatively close to the body surface. (the skin is superficial to underlying structures)
Deep: Toward the interior of the body; farther from the surface. (the bone of the thigh is deep to the surrounding skeletal muscle)
Sectional Planes: What is the Frontal/Coronal plane?
Plane is oriented parallel to the long axis. The section separates anterior and posterior portions of the body.
Sectional Planes: What is the sagittal plane?
Plane is oriented parallel to the long axis. It separates right and left portions.
Midsagittal section: the plane passes through the midline. It separates the body into two equal sides.
Parasagittal section: Misses the midline. It separates the body into unequal sides.
Sectional Planes: What is the Transverse plane?
Is oriented perpendicular to long axis.
A transverse or cross section separates the superior and inferior portions of the body.
What are the 3 groups of joints, based on their range of motion?
- Immovable joint/no movement = Synarthrosis
- Slightly movable/little movement = amphiarthrosis
- Freely movable/free movement = diarthrosis
What are the 3 key types of joints based on anatomy?
- Fibrous
- Cartilagenous
- Synovial
What are the Fibrous joints? (1)
Fibrous tissue unites the bones
- Suture: A synarthrosis joint located only between bones if the skull. The edges of the bones are interlocked and bound together at the suture by dense fibrous connective tissue. They can ossify with age.
What are the Fibrous joints? (2)
- Gomphosis: A synarthrosis that binds the teeth to bony sockets in the maxillae and mandible. Te fibrous connective tissue between a tooth and its socket is the periodontal ligament.
What are the Fibrous joints? (3)
Syndesmosis: at a syndesmosis, bones are connected by a ligament.
e.g. inferior tibiofibular joint
What are the Cartilagenous joints? (1)
Synchondrosis: A rigid, cartilagenous bridge between two articulating bones. Hyaline cartilage unites the bones, allows no movement.
Also called epiphyseal plates when seen during development.
E.g. the cartilagenous connection between the ends of the first pair of vertebrosternal ribs and manubrium of the sternum.
What are the Cartilagenous joints? (2)
Symphysis: Permanent joints, seen in both adults and children.
Each bone has a covering of hyaline cartilage with a disc of fibro-cartilage between them; shock-absorption and weight bearing joints
E.g. between the two pubic bones
What are synovial joints?
Freely movable joints containing synovial fluid and are classified as DIARTHROSES
What are the components of Synovial joints?
- Cartilage: reduces friction & acts as a shock absorber
- Synovial fluid: lubricates the joint
- Synovial membrane: Produces synovial fluid
- Tendon: joins muscle to bone enabling movement
- Ligament: joins bone to bone, stabilising the joint
Synovial plane joint (gliding, slight non-axial or multiaxial = movement on multiple axes)
Have flattened or slightly curved surfaces that slide across one another, but the amount of movement is very slight.
Present in areas that require a small degree of flexibility but also stability.
E.g. Intercarpal joint
Synovial saddle joint (Angular & Biaxial = movement on two axes)
Posses complex articular faces and fit together like a rider & saddle. Each face is concave along one axis and convex along the other.
Permit two angular movements at right angles to each other (to & from and side to side)
E.g. Carpometacarpal joint of the thumb
Synovial hinge joint (Angular & Monoaxial)
Hinge joints permit angular motion in a single plane, like the opening and closing of a door!
Flexion and extension of limbs
E.g. Elbow and interphalangeal joints of the fingers
Synovial modified hinge joint
Temperomandibular joint
Contains a cartilagenous disc that divides the joint into 2 compartments which permit limited side to side and anterior to posterior movements + classic hinge motion
Synovial pivot joint (rotation, monoaxial)
Only permit rotation. Rotation is defined as the movement of a bone around its own longitudinal axis
E.g. Head of the radius rotating in a ring formed by the annular ligament and the ulna
Synovial ellipsoid joint (angular and biaxial)
Also called Condylar joint
Have an oval articular face (convex) nestled within a depression on the opposing surface (concave).
Permit movement in more than one plane - flexion, extension, abduction, adduction and circumduction BUT NO ROTATION
E.g. The wrist and the meta-carpophalangeal joints of the digits
Synovial ball and socket joints (angular & circumduction, rotation; triaxial)
In a ball-and-socket joint, the round head of one bone rests with a cup-shaped depression in another.
Permits widest range of movements of all synovial joints
Allows flexion, extension, abduction, adduction, circumduction, and rotation
E.g. Shoulder joint
