MUSCLE MECHANICS AND CONTROL

Transcription

1 MUSCLE MECHANICS AND CONTROL

2 STRUCTURE OF A SKELETAL MUSCLE

3 NEUROVASCULAR BUNDLE - CONTAINS THE BLOOD VESSELS AND THE NERVES TO A MUSCLE

4 SKELETAL MUSCLE - LONGITUDINAL SECTION

5 MUSCLE ATTACHMENTS: TENDONS APONEUROSIS FLESHY ATTACHMENTS DERMAL ATTACHMENTS

6 TENDON - EXTENSIONS OF CONNECTIVE TISSUE SHEATHS FORMING A CORD-LIKE ATTACHMENT TO A BONE

7 APONEUROSIS - BROAD SHEET OF CONNECTIVE TISSUE TO ATTACH MUSCLE BICIPITAL APONEUROSIS

8 FLESHY ATTACHMENT - MUSCLE FIBERS CONTINUE ALMOST TO THE BONE, VERY LITTLE CONNECTIVE TISSUE

9 DERMAL ATTACHMENT - MUSCLE FIBERS ATTACH TO THE CONNECTIVE TISSUE OF THE DERMIS OF THE SKIN (MUSCLES OF FACIAL EXPRESSION)

10 FASCICLE ARRANGEMENT - SHAPES OF MUSCLES

11 ATTACHMENT POINTS: ORIGINS AND INSERTIONS

12 ORIGIN - PROXIMAL ATTACHMENT, USUALLY LESS MOVEABLE ATTACHMENT INSERTION - DISTAL ATTACHMENT, USUALLY THE MORE FREELY MOVEABLE ATTACHMENT

13 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.

14 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

15 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)

16 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

17 CLASSES OF LEVERS 1st = FULCRUM IN THE MIDDLE 2nd = LOAD IN THE MIDDLE 3rd = EFFORT/FORCE IN THE MIDDLE (MOST COMMON)

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20 MOST COMMON IN THE BODY

21 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

22 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

23 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

24 NEUROMUSCULAR CONTROL: THE CONTROL OF THE SOMATIC MOTOR SYSTEM BY THE NERVOUS SYSTEM - COGNATIVE CONTROL BRAIN upper motor neurons PYRAMIDAL TRACT DESCENDS FROM BRAIN BRAIN STEM lower motor neurons CRANIAL NERVE FROM MOTOR CELLS IN BRAIN STEM SPINAL CORD Lower motor neurons SPINAL NERVES FROM MOTOR CELLS IN SPINAL CORD MUSCLES OF HEAD AND NECK MUSCLES OF BODY

25 PRIMARY MOTOR CORTEX IN FRONTAL LOBE OF BRAIN DIRECTS ALL INTENTIONAL/VOLITIONAL MOVEMENTS. THESE ARE UPPER MOTOR NEURONS. PYRAMIDAL TRACT

26 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

27 CRANIAL NERVES SPINAL NERVES A MOTOR UNIT IS A LOWER MOTOR NEURON AND ALL THE MUSCLE FIBERS IT INNERVATES

28 NEUROMUSCULAR CONTROL: THE CONTROL OF THE SOMATIC MOTOR SYSTEM BY THE NERVOUS SYSTEM BRAIN upper motor neurons PYRAMIDAL TRACT DESCENDS FROM BRAIN BRAIN STEM lower motor neurons CRANIAL NERVE FROM MOTOR CELLS IN BRAIN STEM SPINAL CORD lower motor neurons SPINAL NERVES FROM MOTOR CELLS IN SPINAL CORD MUSCLES OF HEAD AND NECK MUSCLES OF BODY

29 NEUROMUSCULAR JUNCTION - NERVE ENDING AND THE MUSCLE FIBER

30 NEUROMUSCULAR JUNCTION MUSCLE CELL MOTOR END PLATE - FOLDED PART OF THE MUSCLE CELL MEMBRANE MOTOR NERVE

31 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

32 AFFERENT INFORMATION - MESSAGES COMING IN/SENSORY SENSORY TRACT BACK TO BRAIN EFFERENT INFORMATION - MESSAGES GOING OUT/MOTOR PYRAMIDAL TRACT (MOTOR )

33 THE MUSCULAR SYSTEM: MUSCLES OF THE ANTERIOR AND POSTERIOR THORAX

34 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

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37 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* PECTORALIS MINOR SERRATUS ANTERIOR SUBCLAVIUS STERNOCLEIDOMASTOID COVERED LATER

38 PECTORALIS MINOR - TRIANGULAR SHAPED MUSCLE, APEX ATTACHED TO CORACOID PROCESS, DISTAL ATTACHMENT TO RIBS 3-5 STABALIZES SCAPULA, DEPRESS THE SAPULA

39 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

40 SERRATUS ANTERIOR INNERVATED BY LONG THORACIC NERVE LOCATED ON ITS SURFACE

41 SUBCLAVIUS - LIES UNDER CLAVICLE HOLDS CLAVICLE IN STERNOCLAVICULAR JOINT STABIZES THE CLAVICLE PROTECTS UNDERLYING SUBCLAVIAN VESSELS

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43 SUBCLAVIUS PECTORALIS MINOR SERRATUS ANTERIOR PECTORALIS MAJOR

44 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

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46 PLATYSMA STERNOCLEIDOMASTOID

47 MUSCLES OF THE POSTERIOR THORAX LATISSIMUS DORSI (COVERED LATER) TRAPEZIUS LEVATOR SCAPULAE RHOMBOIDS MAJOR AND MINOR

48 TRAPEZIUS - ATTACHES PECTORAL GIRDLE TO TRUNK TRAPEZOID SHAPE FIBERS DIVIDED INTO THREE, THREE DIFFERENT ACTIONS: 1)ELEVATES SCAPULA, 2)RETRACTS SCAPULA, 3)DEPRESSES SCAPULA

49 LIGAMENTUM NUCHAE - ATTACHMENT OF TRAPEZIUS

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51 STERNOCLEIDOMASTOID TRAPEZIUS LATISSIMUS DORSI THORACO - DORSAL FASCIA (APONEUROSIS)

52 LEVATOR SCAPULAE - ELEVATES SCAPULA FIXED SCAPULA, THEN EXTENDS NECK LOCATED SUPERIOR TO THE RHOMBOIDS AT THE SUPERIOR ANGLE OF THE SCAPULA

53 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

54 WHERE DOES THE SERRATUS ANTERIOR ATTACH TO THE SCAPULA?

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56 LEVATOR SCAPULAE STERNOCLEIDOMASTOID RHOMBOID MINOR LEVATOR SCAPULAE RHOMBOID MAJOR LATISSIMUS DORSI