Lecture #1 - ANHS 341

Sagittal Plane

Divides body into left and right; flexion/extension; anterior/posterior tilting; plantarflexion/dorsiflexion

Frontal Plane

Divides body into front and back; abduction/adduction; side bending; elevation/depression; inversion/eversion; upward/downward rotation

Transverse Plane

Divides body into top and bottom; internal/external rotation; spine/pelvis rotation; horizontal ab/adduction; pronation/supination; protraction/retraction

Superior

Toward the head/above

Inferior

Toward the feet/below

Anterior

Toward the front

Posterior

Toward the back

Cranial

Toward the head/skull

Caudal

Toward the tailbone

Proximal

Closer to the point of attachment to the trunk

Distal

Farther from the point of attachment to the trunk

Medial

Toward the midline of the body

Lateral

Away from the midline of the body

Superficial

Toward the body surface

Deep

Away from the body surface

Number of Bones

~206

Functions of Skeletal System

Support, storage, movement, red blood cell formation

Ligament

Connects bone to bone

Diaphysis

Shaft of a long bone

Epiphysis

End of a long bone

Process

Projection or bump on a bone

Tuberosity

Large rounded projection

Tubercle

Small rounded projection

Spine (bone feature)

Sharp slender projection

Condyle

Rounded articular area

Epicondyle

Raised area on or above a condyle

Fossa

Shallow depression in bone

Foramen

Round or oval opening in bone

Tendon

Connects muscle to bone

Origin

Attachment on the more stationary bone

Insertion

Attachment on the more mobile bone

Reverse Muscle Action

Origin moves instead of insertion (closed chain)

Isotonic Contraction

Tension remains constant while muscle shortens or lengthens

Concentric Contraction

Muscle shortens while generating force

Eccentric Contraction

Muscle lengthens while controlling resistance (acts like a brake)

Isometric Contraction

Muscle develops tension but does not change length

Isokinetic Contraction

Muscle contracts at constant speed using a machine

Agonist (Prime Mover)

Directly responsible for producing movement

Assistant Mover

Helps the prime mover only when needed

Synergist

Assists movement by stabilizing or neutralizing unwanted actions

Antagonist

Opposes agonist; relaxes to permit movement and acts as a brake

Biarticular Muscle

Muscle that crosses and acts on two joints

Muscle Shortening Capacity

Muscle can shorten to ~66% of resting length

Longitudinal Muscle

Good range of motion but less strong

Pennate Muscle

Stronger but less range of motion

Physiological Cross Section (PCS)

Determines how much force a muscle can produce

Line of Pull

Movement determined by joint type and muscle fiber direction

Fascia

Fibrous connective tissue covering and supporting muscles

Aponeurosis

Flat sheet of fibrous tissue acting like a tendon

Septum

Wall dividing a cavity or structure into smaller ones

Interosseous Membrane

Sheet of fibrous tissue connecting long bones (radius/ulna, tibia/fibula)

Retinaculum

Band that holds tendons in place to stabilize them

Spine Movements

Flexion, extension, lateral flexion, rotation

Neck Movements

Flexion, extension, rotation, lateral flexion

Ribs and Thorax Movements

Elevation and depression

Scapula Movements

Elevation, depression, protraction, retraction, upward rotation, downward rotation

Shoulder Movements

Flexion, extension, abduction, adduction, horizontal abduction/adduction, internal/external rotation

Elbow Movements

Flexion and extension

Forearm Movements

Pronation and supination

Wrist Movements

Flexion, extension, radial deviation, ulnar deviation

Finger Movements

Flexion, extension, abduction, adduction

Thumb Movements

Flexion, extension, abduction, adduction, opposition, reposition

Mandible Movements

Elevation, depression, protraction, retraction, lateral deviation

Pelvis Movements

Anterior tilt, posterior tilt, lateral tilt, rotation

Hip Movements

Flexion, extension, abduction, adduction, internal/external rotation

Knee Movements

Flexion and extension

Ankle Movements

Dorsiflexion and plantarflexion

Foot Movements

Inversion and eversion

Toe Movements

Flexion, extension, abduction, adduction