Download MUSCLE MECHANICS AND CONTROL

MUSCLE MECHANICS AND CONTROL
STRUCTURE OF A SKELETAL MUSCLE
NEUROVASCULAR
BUNDLE - CONTAINS
THE BLOOD VESSELS
AND THE NERVES TO
A MUSCLE
SKELETAL MUSCLE - LONGITUDINAL
SECTION
MUSCLE ATTACHMENTS:
TENDONS
APONEUROSIS
FLESHY ATTACHMENTS
DERMAL ATTACHMENTS
TENDON - EXTENSIONS OF CONNECTIVE TISSUE
SHEATHS FORMING A CORD-LIKE ATTACHMENT TO
A BONE
APONEUROSIS - BROAD SHEET OF CONNECTIVE
TISSUE TO ATTACH MUSCLE
BICIPITAL
APONEUROSIS
FLESHY ATTACHMENT - MUSCLE FIBERS
CONTINUE ALMOST TO THE BONE, VERY LITTLE
CONNECTIVE TISSUE
DERMAL ATTACHMENT - MUSCLE FIBERS ATTACH
TO THE CONNECTIVE TISSUE OF THE DERMIS OF
THE SKIN (MUSCLES OF FACIAL EXPRESSION)
FASCICLE ARRANGEMENT - SHAPES OF MUSCLES
ATTACHMENT POINTS: ORIGINS AND INSERTIONS
ORIGIN PROXIMAL
ATTACHMENT,
USUALLY LESS
MOVEABLE
ATTACHMENT
INSERTION DISTAL
ATTACHMENT,
USUALLY THE
MORE FREELY
MOVEABLE
ATTACHMENT
MUSCLES MUST CROSS A JOINT TO CAUSE
AN ACTION
DEPENDING ON THE AXIS OF THE JOINT
CROSSED, THE MOVEMENT IS DETERMINED
THE AXIS IS ALWAYS PERPENDICULAR TO
THE PLANE OF MOVEMENT.
THE SHOULDER JOINT:
MOVEMENT ABOUT THE SAGITTAL
(ANTERIOR POSTERIOR , AP) OR
TRANSVERSE AXIS IS IN THE FRONTAL
PLANE
MOVEMENT ABOUT THE TRANSVERSE OR
FRONTAL AXIS IS IN THE SAGITTAL
PLANE
MOVEMENT ABOUT THE FRONTAL
(LONGITUDINAL) OR SAGITTAL AXIS IS IN
THE TRANSVERSE PLANE
LEVER SYSTEMS: BONE - MUSCLE
RELATIONSHIPS
COMPONENTS:
LEVER - ELONGATED RIGID OBJECT THAT ROTATES
AROUND A FIXED POINT
(BONE)
FULCRUM - FIXED POINT AROUND WHICH THE LEVERS
WILL ROTATE (AXIS)
(JOINT)
FORCE/EFFORT - EFFORT APPLIED AT ONE END OF THE
LEVER TO OVERCOME A WEIGHT OR LOAD
(MUSCLE)
LOAD - THE WEIGHT OR RESISTANCE AT SOME POINT
OF THE LEVER THAT WILL BE OVERCOME BY THE
FORCE
(WEIGHT OF BODY PART TO BE MOVED)
LEVER SYSTEM
• IN THE HUMAN BODY…
- LEVERS = RIGID BONES
- AXIS/FULCRUM OR PIVOT POINTS = JOINTS, MOST
COMMONLY DIARTHRODIAL
- FORCES/EFFORT = MUSCLES
- RESISTANCE/LOAD = GRAVITY, OR OTHER EXTERNALLY
APPLIED RESISTANCE (WEIGHTS)
(F) - Effort/ force
Lever
Fulcrum/Axis
(R) - Resistance/load
CLASSES OF LEVERS
1st = FULCRUM IN THE MIDDLE
2nd = LOAD IN THE MIDDLE
3rd = EFFORT/FORCE IN THE MIDDLE
(MOST COMMON)
MOST
COMMON IN
THE BODY
THIRD-CLASS LEVERS AND
HUMAN MOVEMENT
THIRD CLASS LEVERS ARE DESIGNED TO
INCREASE SPEED AND ROM OF THE DISTAL END
OF THE LEVER.
THE FORCE THAT MUST BE GENERATED IS MUCH
GREATER THAN THE LOAD BEING MOVED BUT IT
WILL MOVE IT OVER A GREATER DISTANCE, OR
GREATER RANGE OF MOTION.
- GOAL OF HUMAN MOTION IS TO MOVE
THROUGH SPACE
- 3rd CLASS LEVERS ACHIEVE OUR OBJECTIVE TO
MOVE THROUGH SPACE
INTERACTION OF SKELETAL MUSCLES TO
PRODUCE AN ACTION:
PRIME MOVER OR AGONIST - MOST EFFECTIVE IN
CAUSING THE MOVEMENT
ANTAGONIST - OPPOSITE OF THE AGONIST,
REVERSE MOVEMENT
SYNERGIST - HELPS PRIME MOVER AND
REDUCES UNDESIRABLE MOVEMENT THAT MAY
OCCUR
FIXATORS OR STABILIZERS - ANCHORS,
STEADIES OR SUPPORTS A BONE OR BODY PART
SO THAT AN ACTIVE MUSCLE HAS A FIRM BASE
ON WHICH TO PULL
RHOMBOIDS (MAJOR AND MINOR) ACTION ON
THE SCAPULA:
RHOMBOIDS RETRACT THE SCAPULA AS
AGONISTS OR PRIME MOVERS
RHOMBOIDS ARE ANTAGONISTS TO THE
SERRATUS ANTERIOR MUSCLE WHICH
PROTRACTS THE SCAPULA
RHOMBOIDS ARE STABALIZERS OF THE
SCAPULA TO ALLOW THE LEVATOR SCAPULAE
TO EXTEND THE NECK
RHOMBOIDS ARE SYNERGISTIC TO RETRACTION
OF THE SCAPULA WITH THE MIDDLE FIBERS OF
THE TRAPEZIUS
NEUROMUSCULAR CONTROL: THE CONTROL
OF THE SOMATIC MOTOR SYSTEM BY THE
NERVOUS SYSTEM - COGNATIVE CONTROL
BRAIN
upper motor neurons
PYRAMIDAL TRACT
DESCENDS
BRAIN STEM
FROM BRAIN
lower motor neurons
CRANIAL NERVE
FROM MOTOR
CELLS IN BRAIN
STEM
MUSCLES
OF HEAD AND NECK
SPINAL CORD
Lower motor neurons
SPINAL NERVES
FROM MOTOR CELLS
IN SPINAL CORD
MUSCLES OF BODY
PRIMARY MOTOR CORTEX IN FRONTAL LOBE OF
BRAIN DIRECTS ALL INTENTIONAL/VOLITIONAL
MOVEMENTS. THESE ARE UPPER MOTOR
NEURONS.
PYRAMIDAL
TRACT
LOWER MOTOR NEURONS - MOTOR NEURONS,
LOCATED IN BOTH THE SPINAL CORD AND
CRANIAL NERVE NUCLEI
UPPER MOTOR NEURON SIGNALS
(lower motor neurons/cells)
EFFERENT
INFORMATION
CRANIAL NERVES
SPINAL NERVES
A MOTOR UNIT IS A
LOWER MOTOR
NEURON AND ALL THE
MUSCLE FIBERS IT
INNERVATES
NEUROMUSCULAR CONTROL: THE CONTROL
OF THE SOMATIC MOTOR SYSTEM BY THE
NERVOUS SYSTEM
BRAIN
upper motor neurons
PYRAMIDAL TRACT
DESCENDS
BRAIN STEM
FROM BRAIN
lower motor neurons
CRANIAL NERVE
FROM MOTOR
CELLS IN BRAIN
STEM
MUSCLES
OF HEAD AND NECK
SPINAL CORD
lower motor neurons
SPINAL NERVES
FROM MOTOR CELLS
IN SPINAL CORD
MUSCLES OF BODY
NEUROMUSCULAR JUNCTION - NERVE ENDING
AND THE MUSCLE FIBER
NEUROMUSCULAR
JUNCTION
MUSCLE
CELL
MOTOR END
PLATE - FOLDED
PART OF THE
MUSCLE CELL
MEMBRANE
MOTOR NERVE
SENSORY FEEDBACK TO THE BRAIN FROM
THE MUSCLES: PROPRIOCEPTION (THE
SENSE OF KNOWING WHERE OUR BODY IS IN
SPACE)
VIA MUSCLE SPINDLES AND GOLGI TENDON
ORGANS
AFFERENT INFORMATION MESSAGES COMING IN/SENSORY
EFFERENT INFORMATION MESSAGES GOING OUT/MOTOR
SENSORY
TRACT BACK
TO BRAIN
PYRAMIDAL
TRACT (MOTOR )
THE MUSCULAR
SYSTEM:
MUSCLES OF THE
ANTERIOR AND
POSTERIOR THORAX
MUSCULAR SYSTEM:
MOVEMENT OCCURS WHEN THE MUSCLE
EXERTS A FORCE ON THE STRUCTURE INTO
WHICH IT IS INSERTED AND PULLS IT TOWARD
ITS POINT OF ORIGIN
NAMING: ACTION, SHAPE, LOCATION
WHAT TO KNOW: MUSCLE’S NAME
LOCATION: ATTACHEMNTS
(ORIGIN AND INSERTION)
ACTION
INNERVATION
MUSCLES OF THE ANTERIOR AND POSTERIOR
THORAX:
ATTACH UPPER LIMB TO THE AXIAL SKELETON
VIA THE PECTORAL GIRDLE
STABILIZE THE SHOULDER AND MOVE THE
SCAPULA
MUSCLES OF THE ANTERIOR THORAX:
PECTORALIS MAJOR*
COVERED LATER
PECTORALIS MINOR
SERRATUS ANTERIOR
SUBCLAVIUS
STERNOCLEIDOMASTOID
PECTORALIS MINOR TRIANGULAR SHAPED
MUSCLE, APEX
ATTACHED TO
CORACOID PROCESS,
DISTAL ATTACHMENT
TO RIBS 3-5
STABALIZES
SCAPULA, DEPRESS
THE SAPULA
SERRATUS ANTERIOR
SCALLOPED ORIGIN,
SERRATUS (SAWLIKE)
INSERTS ONTO MEDIAL
BORDER OF SCAPULA
HOLDS SCAPULA
AGAINST THE CHEST
IMPORTANT TO
PROTRACT THE
SCAPULA (MOVE IT
OUTWARD)
NEEDED TO ELEVATE
THE ARM ABOVE 90°
SERRATUS ANTERIOR
INNERVATED BY LONG THORACIC
NERVE LOCATED ON ITS SURFACE
SUBCLAVIUS LIES UNDER
CLAVICLE
HOLDS CLAVICLE IN
STERNOCLAVICULAR
JOINT
STABIZES THE
CLAVICLE
PROTECTS
UNDERLYING
SUBCLAVIAN
VESSELS
SUBCLAVIUS
PECTORALIS
MINOR
SERRATUS
ANTERIOR
PECTORALIS MAJOR
STERNOCLEIDOMASTOID - ANTERIOR NECK
MUSCLE, 2 HEADS: CLAVICULAR & STERNAL
ATTACHES
PECTORAL
GIRDLE TO
AXIAL
SKELETON
BILATERALLY
(?) FLEXES
HEAD
FORWARD
UNILATERALLY
FLEXES HEAD
TO SAME SIDE
AND TURNS
FACE TO
OPPOSITE SIDE
PLATYSMA
STERNOCLEIDOMASTOID
MUSCLES OF THE POSTERIOR THORAX
LATISSIMUS DORSI (COVERED LATER)
TRAPEZIUS
LEVATOR SCAPULAE
RHOMBOIDS MAJOR AND MINOR
TRAPEZIUS ATTACHES
PECTORAL GIRDLE
TO TRUNK
TRAPEZOID SHAPE
FIBERS DIVIDED
INTO THREE,
THREE DIFFERENT
ACTIONS:
1)ELEVATES
SCAPULA,
2)RETRACTS
SCAPULA,
3)DEPRESSES
SCAPULA
LIGAMENTUM NUCHAE - ATTACHMENT OF
TRAPEZIUS
STERNOCLEIDOMASTOID
TRAPEZIUS
LATISSIMUS DORSI
THORACO DORSAL FASCIA
(APONEUROSIS)
LEVATOR
SCAPULAE ELEVATES
SCAPULA
FIXED SCAPULA,
THEN EXTENDS
NECK
LOCATED
SUPERIOR TO THE
RHOMBOIDS AT
THE SUPERIOR
ANGLE OF THE
SCAPULA
RHOMBOID
MAJOR AND
MINOR - OFTEN
NOT CLEARLY
SEPARATED
MINOR
SUPERIOR TO
MAJOR AT THE
LEVEL OF THE
SCAPULAR
SPINE
MAJOR 3-4X
WIDER THAN
MINOR,
LOCATED
INFERIOR TO
MINOR
WHERE DOES THE SERRATUS ANTERIOR ATTACH TO THE
SCAPULA?
LEVATOR SCAPULAE
STERNOCLEIDOMASTOID
RHOMBOID
MINOR
LEVATOR SCAPULAE
RHOMBOID
MAJOR
LATISSIMUS
DORSI