Locomotion Intro Flashcards
Two types of movement
- Regional
- Whole Body Movement
Regional Movement can be
- Involuntary (smooth/cardiac muscle)
- Voluntary (skeletal muscle)
Whole Body Movement can be
- Vertical (standing up, lying down, kicking, etc)
- Horizontal (terrestrial animals)
Components of the Locomotion System include 5
-bones
-joints
-muscles (skeletal)
-nerves
-blood vessels
Joints are
anywhere where two bones come together
Muscles run
from one bone to another
Function of bones: (5)
-support
-protection
-movement and muscle attachment
-mineral homeostasis (ie. Calcium)
-haemopoiesis (ie. production of blood cells)
Types of Bones: (4)
-long (movement)
-short (reduce friction and shock absorption)
-flat (protection; muscle attachment)
-irregular
The largest Sesamoid Bone in the body is the
Patella (kneecap)
Long Bone example
Bones of the limb
Short Bone example
Sesamoid Bones
Flat Bone examples
-bones of the skull
-scapula
Irregular Bone examples
-vertebrae
-base of skull (sphenoid)
Sesamoid bones develop in response to
friction in utero
Stress is
an external force (ex. lifting weights)
Strain is
How the body responds to stress
Main cell for growing bone
Osteoblast
Two types of bone development
-membranous bones
-cartilaginous bones
Cartilaginous bones: (4)
-develop in utero
-most common
-develop from pre-existing cartilage
-ex. most bones of skeleton, irregular bones at base of skull
Membranous bones: (2)
-develop on layers of collagen fibres
-ex. flat bones of the skull
Tensile strength is
Pulling
Compressional strength is
Pushing
Many bones are
hollow
Where bone meets bone
articular cartilage
Parts of the Long Bone (3)
-Epiphysis (extremity)
-Diaphysis (shaft)
-Metaphysis
The Growth Plate is also called ___ and does ____
-Epiphyseal Cartilage
-separates epiphysis from rest of the bone
The Epiphysis is
the proximal and distal ends of the bone
Compact bone is
The dense, external layer
Spongy (Cancellous) bone is
The internal layer of the bone containing spicules (trabeculae)
Three layers of bone
-Periosteum
-Endosteum
-Medullary Cavity
External membrane of bone
Periosteum
Periosteum is: (4)
-the external membrane of bone
-contains nerves and blood vessels
-continuous with tendons
-thick and tough
Endosteum is:
the internal membrane of bone that lines the medullary cavity
The Medullary Cavity is: (3)
-hollow center within the Diaphysis
-Red marrow in young animals
-Yellow marrow (fat) in mature animals
Major blood vessel of bones is ___ and enters through ____
-Nutrient Artery
-Nutrient Foramen
The Nutrient Artery branches into
The proximal and distal medullary arteries
When two arteries come together, it is called
Anastomose
Two arteries that anastomose with the Medullary Artery are:
-Periosteal arterioles
-Metaphyseal artery
The periosteal arterioles supply
the outer cortex of the diaphysis in areas of strong fascial attachment
In young animals, this artery is present
Epiphyseal Artery
The epiphyseal artery is: (2)
-present only in young animals
-separates blood vessels
Joints are formed when
Two or more bones unite via fibrous (elastic) or cartilaginous tissue
Three types of joints
-Fibrous
-Cartilaginous
-Synovial
Fibrous joints are further divided into (3)
-Suture
-Syndesmosis
-Gomphosis
Cartilaginous joints are further divided into (2)
-Symphysis
-Synchrondosis
Joint with least movement are
Fibrous
Joint with most movement are
Synovial
Fibrous Joints are: (5)
-held together by fibrous connective tissue
-have little movement
-are short, direct, and often transitory (ie. become ossified during maturation)
-lack a joint cavity
-Suture, Syndesmosis, Gomphosis
Which joint(s) lack a joint capsule
-Fibrous
-Cartilaginous
Sutures are: (4)
-fibrous joints
-flat bones of skull
-little movement but allow for growth
-transitory
Once matured, suture joints
Ossify to form Synostosis
Bregma
meeting of two suture joints (sagittal and coronal)
Fontanelle
hole in head
Syndesmosis are (2) and 2 examples:
-fibrous joints with intervening tissue
-have more movement than sutures but still restricted
Examples:
-tibia to fibula
-splint bone in horse
Gomphosis are: (3)
-a type of fibrous joint
-peg in socket joint (ex. tooth in gum)
-slight movement but firm attachment
Cartilaginous Joints are: (4)
-formed from cartilage, fibro-cartilage, or both
-lack a joint capsule
-limited movement (mainly compression and stretching)
-Symphysis, Synchondrosis
Symphysis are ___ and include ____
-a fibrocartilaginous joint
Includes:
-Pelvic Symphysis
-Mandibular Symphysis
-Intervertebral Joints
-Intersternebral Joints
Intervertebral discs are
between the centrum and body of the vertebrae, used for compression/tension
Synchondrosis are: (3)
-made of hyaline cartilage (ie. no fibrous material)
-can be transitory (Epiphyseal Cartilage/Growth Plate)
-can be permanent (Costochondral Joint and Hyoid to skull)
Synovial Joints have (2)
-greatest movement
-high levels of injury and pathology
All Synovial Joints contain: (4)
-joint capsule (encloses the joint)
-joint cavity (contains synovial fluid)
-synovial fluid
-articular cartilage (usually hyaline, located at the ends of bones)
Joints can be classified by: (3)
-structure
-articulation
-shape
A simple joint is ___ and an example is ___
-two articular surfaces in joint
-shoulder (scapula to humerus)
A compound joint is ___ and an example is ___
-2+ articular surfaces in joint
-elbow (humerus to radius and ulna)
5 Joint Shapes and an example of each:
-Ball & Socket/Enarthrosis (hip, shoulder)
-Hinge/Ginglymus (elbow)
-Condylar (stifle)
-Pivot/Trochoid (atlanto-axial)
-Gliding/Arthrodial (carpometacarpal)
The Synovial Membrane is made of
the Stratum Fibrosum and Stratum Synoviale
Two layers of the joint capsule
-Stratum Fibrosum (thick, outer layer)
-Stratum Synoviale (thin, inner layer)
Stratum Synoviale (4)
-thin, inner layer of joint capsule
-made of loose connective tissue
-phagocytic
-secretes hyaluronan
What membrane encapsulates the joint
Synovial Membrane
Functions of Joint Capsule: (3)
-absorption
-lubricate
-protect
Functions of Articular Cartilage: (2)
-reduce friction
-shock absorption
Articular Cartilage is: (2)
-normally made of hyaline cartilage
-avascular (no nerves)
Functions of Synovial Fluid: (3)
-nutrition of articular cartilage
-lubrication
-shock absorption
Synovial Fluid contains
mucopolysaccharides (hyaluronan)
Ligaments: (5)
-are thickenings of Stratum Fibrosum (outer layer of synovial membrane)
-respond to tensional forces
-strengthen the joints
-restrain movement (overextension/overflexion)
-almost pure collagen
Menisci are ___ and found in ___
-special fibrocartilage articular structures containing a nerve supply
-Stifle and Temporo-mandibular joints ONLY
Flexion
Reduction in angle of joint
Extension
Increase in angle of joint
Abduction
Movement away from the midline
Adduction
Movement toward midline of body
Bursae and Tendon Sheaths
Reduce friction between the tendon and bone
Sesamoid Bones develop
as bones within the tendon
Three types of muscle
-Smooth (Visceral)
-Skeletal (Striated)
-Cardiac
Functions of muscle: (4)
-produce movement
-restrain movement
-support joints
-produce heat
Individual muscles are composed of
long muscle fibres
Fibres can be (2)
-Type I (slow twitch)
-Type II (fast twitch)
Slow twitch fibres/muscles are (4)
-aerobic
-small
-weak
-endurance
Fast twitch fibres/muscles are (6)
-anaerobic
-large
-strong
-used infrequently
-build up lactic acid and oxygen debt
-sporadic busts of energy
Muscles are separated by
Fascia (ie. connective tissue)
Skeletal Muscles are named according to: (5)
-function
-position
-direction of fibres
-shape
-form
Deep fascia (2)
-thick, heavy
-immediately around muscle, continues as tendon
Superficial fascia (2)
-loose
-connects skin to underlying muscle
Fascia is also called
Epimysium
Tendons (3)
-thinner than muscle
-stronger than bone
-some elasticity
Origin (2)
-least movement
-usually proximal
Insertion
-most movement
-usually distal
Muscles exert force by
Contraction of individual muscle fibres (ie. more fibres = greater strength)
Fusiform Muscle (3)
-fibres converge on tendon
-muscle is spindle-shaped
-ex. biceps
Pennate Muscle (3)
-most common
-long tendon attachment at an angle
-can be unipennate, bipennate, or multipennate
The Clavicular Tendon
divides Brachiocephalic muscle into three parts
Rectus Abdominis are
fibrous lines that run across the belly (ie. 6 pack)
New fibres are
NOT normally formed post-natal
Forelimb of domestic mammals has
No bony connection to the body (clavicle in some mammals ie. primates)
An alliance of muscles is called
Synsarcosis
Two types of limbs in Eutherian Mammals:
-Graviportal (weight bearing)
-Cursorial (running)
Graviportal Limbs: (4)
-bones are short and thick
-feet are short
-calcaneous is large and close to end of digits (limited range but powerful movement)
-adapted for weight bearing (ex. elephant)
Cursorial Limbs: (4)
-bones are long and thin
-feet are long
-calcaneous is short (weak movement but large range)
-adapted for running (ex. dog, horse)
Plantigrade
-whole foot is in contact with the ground (ex. bear)
Digitigrade
-only the distal ends of the metacarpals/tarsals and digits are in contact with the ground (ex. dog)
Unguligrade
-only the distal end of the digit is in contact with the ground (ex. horse)
Muscles above the spinal cord
Epaxial
The pectoral girdle in mammals (3)
-became simplified
-reduction in clavicle and coracoid
-scapula developed a spine for muscle attachment
Muscles below the spinal cord
Hypaxial
Pelvic girdle of mammals contains (3)
-ilium that projects cranially
-ischium from muscle attachment
-pubis joined ventrally creating the Pelvic Symphysis
Two major events during reptile to mammal transition:
-horizontal to vertical stance
-rotation of limbs
Dorsal Muscle Mass (forelimb, hindlimb, and nerve)
Forelimb:
-caudal above elbow
-cranial below elbow
Hindlimb:
-cranial
Nerve:
-radial
Ventral Muscle Mass (forelimb, hindlimb, and nerve)
Forelimb:
-cranial above elbow
-caudal below elbow
Hindlimb:
-caudal
Nerves:
-musculo-cutaneous, median, ulnar
