1. Muscles & Joints Ch. 8

2. Movements of the body Flexion: >in angle of a jt. By bending it. Extension: < in angle of jt. By straightening it. Hyperextension: extension beyond the anatomical position Abduction: moving away from midline Adduction: moving toward midline

3. movements Dorsi flexion: bending ankle so foot moves toward the shin. Plantar flexion: bending ankle so foot points downward Inversion: moving foot so sole move inward( medially) Eversion: moving sole of foot outward( laterally)

4. movements Circumduction: circular movement along the length of body part. Rotation: twisting around the axis of limb internal rotation: moves medially external rotation: moves laterally Elevation: raising body part Depression: lowering body part

5. movements Supination: turning hand palm up Pronation: turning hand palm down Protraction: moving part forward Retraction: moving part backward

6. joints 1. Form where bones meet –Joints are functional junctions between bones 2. Related terms articulation: junction of 2 or more bones arthro: joint arthology: study of joints arthritis: inflammation of the joint Arthroscopic: joint scope surgery

7. Joints 3. Functional vs. structural Functional classification is based on: Available movement Structural classification is based on: Materials that make up the joint

8. Joints 4. Functional classification Synarthroidal= immovable examples: sutures, coccyx-sacrum Amphiarthroidal= slightly moveable examples: pubic symphysis, ribs, vetebral disks, intervertebral jts. Diarthroidal= freely moveable examples: all synovial jts.

9. joints 5. Structural classification –Fibrous –Cartilagenous –synovial

10. Joints of the body 6.Fibrous Joints –Syndesmoses (amphiarthroidal) Bones held together by connective tissue(interoseous membrane) Tibia-fibula/Radius-Ulna –Suture (synarthroidal) Between flat bones –Gomphosis ( synarthroidal) Teeth to jaw

11. joints 7. Cartilagenous –Temporary: Synchondrosis (synarthroidal) (bone-cartilage-bone) Slightly movable: compression Example –Epiphyseal plates –1 st rib/manubrium –Permanent: Symphasis ( amphiarthroidal) Example –Pubis symphasis –Intervertebral jts

12. Joints 8.Synovial –Freely moveable –All are diarthroidal –Synovial membrane- secretes synovial fluid Lubricates joint –Joint capsule( fibrous tissue- ligament) –Articular ( Hyaline) cartilage ( meniscus/menisci) –Bursae: fluid filled sacs Reduce friction

13. Joints 8. Types of synovial joints ball & socket condyloid gliding hinge pivot saddle

14. joints 10. Ball & Socket allows for greatest Range of Motion( ROM) shoulder & hip triaxial movement flexion-extension-add/abduction- rotation

15. joints Condyloid ( ellipsoidal) –Egg in spoon –Flexion/extension- add/abduction –Wrist- MCP, MTP, IP, PIP, DIP Gliding joint (plane) –Articular ends nearly flat or slightly curved. –Inter (carpal/tarsal), vertebrae, SI joint

16. Joints –Hinge spool & cap Flexion/extension – elbow, Knee, ankle (talus-tib/fib) –Pivot –Cylinder within a ring –Rotation »Radio-humeral, atlas-axis RadiusUlna

17. Joints Saddle –Saddle on a horse Flexion/ext, abd/adduction Carpometacarpal of thumb

18. muscles 3 types –Skeletal (striated, voluntary) –Cardiac (striated, involuntary) –Smooth ( involuntary) Characteristics –Irritability: ability to respond to stimuli –Contractility: ability to change length –Extensibility: ability to be stretched –Elasticity: ability to return to original shape

19. Muscle facts Most common type of tissue in the body (over 600) Makes up 35-45% of body weight Muscles produce action only by pulling, they cannot push Tendons connect bones to muscle One muscle may attach to another through an aponeurosis (tendon) Each muscle is made up of many bundles of fibers Each fiber is an individual cell Cells are multinucleated They are thin, elongated cylinders Each cell may run the entire length of a muscle

20. Features of a muscle Epimysium; muscle facia; outer covering of muscle Perimysium: sheath that separates muscle cells into fascicles Fasicle: bundle of muscle fibers Endomysium: thin covering around each muscle fiber Sarcolemma: membrane of the muscle cell Sarcoplasm: cytoplasm of muscle cell Muscle fiber: muscle cell composed of many myofibrils Myofibril: threadlike structures within sarcoplasm essential for contraction, made of myofilaments. Myofilaments: protein strands actin (thin) and myosin (thick). Give striped appearance to muscle. Sarcomere: functional unit of muscle contraction between Z-lines of each myofibril. Myosin filament: Thick dark filament, make up A bands of sarcomere, contains cross-bridges that connect them to the thin filaments. Actin Filaments: Thin, light colored filaments, make up I bands connected together at Z lines, move with a muscle contraction.

21. Muscle fiber Actin & myosin filaments fasicle

22. Muscle cell diagram actin myosin Z-line Sarcomere Z line –Z line A-Band I-band H- band Cross bridge sarcomere

23. Sarcomere contractile unit of muscle Actin: thin myofilament, troponin & tropomyosin Myosin: thick myofilament, has crossbridges. Z-line: connects ends of actin together, move toward each other during contraction A band: full length of myosin fiber within a sarcomere, between I bands I band: end of myosin in one sarcomere to the myosin in the next sarcomere. H- band: in the middle of the sarcomere between ends of actin gets smaller with contractions. Crossbridge: functional unit of myosin that attach to troponin/tropomyosin heads on actin filament to cause contraction

24. Muscle contraction 8.3-8.4

25. Muscle contraction

26. Lets watch a sarcomere shortening http://highered.mcgraw- hill.com/sites/0072437316/student_view0/ chapter42/animations.html#http://highered.mcgraw- hill.com/sites/0072437316/student_view0/ chapter42/animations.html# Now let’s discover how this process occurs

27. Muscle contraction (sliding filament theory) 1.Nerve impulse travels down a motor neuron to muscle unit. 2.The motor neuron terminal releases neurotransmitter acetylcholine (ACh) 3.ACh binds to ACh receptors (nicotinic receptor) on muscle Motor end unit http://glencoe.mcgraw- hill.com/sites/0015081981/student_view0/chapter8/function_of_the_neuromuscular_j unction_.html

28. 4.The sarcolemma is stimulated and the muscle impulse travels over the surface of the muscle fiber into the transverse tubules. 5. The impulse reaches the sarcoplasmic reticulum and Ca+ channels open 6. Ca+ ions diffuse from the sarcoplamic reticulum into the sarcoplasm and bind to troponin molecules. Muscle contraction (sliding filament theory) 4.4. 5 6.6.

29. Ca+ and it’s role in muscle contraction http://www.youtube.com/watch?v=vv6WBe qw2Nchttp://www.youtube.com/watch?v=vv6WBe qw2Nc

30. Thin filaments slide past the thick filaments and the sarcomere shortens. Myosin molecule has a head and a tail –Tail is a hinge allowing head to attach to actin –Head has a power stroke to pull actin molecule. Muscle contraction (sliding filament theory)

31. Myosin uses ATP to contract ( head has binding site for actin & ATP) Actin molecule has 2 proteins: troponin & tropomyosin –Tropomyosin covers binding site so myosin cannot bind ( prevents contraction) –Troponin exposed binding sites ( w/Ca+)

32. 7. Ca+ ions released by action potential of nerve causes tropomyosin to move off of binding site. 8. Cross-bridge flexes and binds to actin molecule. 9. Head flexes (power stroke) and pulls the actin, thus shortening the sarcomere ( muscle contraction)

33. Sliding filament in action Myofilament Contraction

34. Sarcomere shortening http://glencoe.mcgraw- hill.com/sites/0015081981/student_view0/ chapter8/action_potentials_and_muscle_c ontraction.htmlhttp://glencoe.mcgraw- hill.com/sites/0015081981/student_view0/ chapter8/action_potentials_and_muscle_c ontraction.html

35. Muscle relaxation 1.Acetylcholinesterase(enzyme) decomposes ACh, and the muscle fiber membrane is no longer stimulated (no ATP) 2.CA+ ions are actively transported back into sarcoplasmic reticulum. 3.ATP breaks linkages between actin & myosin filaments 4.Tropomyosin slides back over myosin binding sites 5.Muscle is relaxed and ready for next contraction Break down of ATP http://glencoe.mcgraw-hill.com/sites/0015081981/student_view0/chapter8/breakdown_of_atp_and_cross- bridge_movement_during_muscle_contraction.html

36. -We use creatine phosphate to re charge the ATP molecule -Has High energy phosphate bonds -4-6x more abundant in muscle than ATP -Active muscle uses Creatine Phosphate rapidly.- uses cellular respiration after creatine is gone. -Krebs cycle in aerobic environments -lactic acid fermentation in anaerobic Energy source is ATP

37. Figure 08.10

38. Figure 08.11

39. Oxygen supply -Myoglobin (like hemoglobin) helps provide muscle with extra oxygen during respiration. -Oxygen Debt -During strenuous muscle use, anaerobic path ways are used to obtain energy (1-2 mins) - the amount of Oxygen the liver needs to covert lactic acid to glucose + the amount of oxygen required to restore ATP/creatine phosphate back to original concentrations) VERY SLOW process -Can train to increase aerobic capacity -Fatigue is usually caused from a build up of lactic acid. -Lowers pH so muscle cells no longer respond to stimuli

40. Muscle control All-or-nothing response –Threshold: weakest stimuli to elicit a response -muscle fibers have different thresholds. must have threshold for muscle to contract (twitch) -Frequency fibers are stimulated & how many are stimulated determine contractile force -Recruitment of fibers occurs with larger stimuli

41. Muscle parts 3 main parts –Origin= proximal; usually immovable 2 origins= biceps 3 origins= triceps 4 origins= quadriceps –Insertion= distal attachment, usually movable –Belly= “body” of muscle, between O & I belly

42. Muscle names Named for their –Action ( flexor, extensor) –Location (carpi, tibialis) –Shape and size ( deltoid, maximus, longus) –Number of attachments ( bi, tri..) –Point of attachment ( sternocleidomastoid) –Direction of their fibers ( transverse, oblique)

43. Muscle work in groups Prime mover (agonist) Muscle primarily responsible for movement –Ex. Deltoid-abducting arm/biceps-arm flexion Synergist assist prime mover –Make movements more smooth and efficient –Ex. Rotator cuff deltoid in arm Abduction Antagonist performs opposite of agonist –Ex. Triceps/biceps; quad/hamstrings biceps triceps Brachialis (under biceps)

44. Muscles of the face Muscles of facial expression(6) –Epicranius: –Orbicularis oris –Orbicularis oculi –Buccinator –Zygomaticus –Platysma Muscles of mastication(2) –Masseter –Temporalis

45. 1.epicranius: lifts eye brows “flirting: frontalis+ occiptalis 2. Orbicularis oculi: closes eye “winking” 3. Orbicularis oris: close mouth “kissing” 4. Buccinator: compress cheeks in “whistle” 5. 4. 5. zygomaticus: raises corner of mouth “smile”

46. 6. platysma: draws angle of mouth downward “pout” 7. Sternocleidomastoid: Turns head to side, pulls head to chest, raises sternum 6. 7.

47. 8. masseter: elevates mandible “chew” 9.Temporalis: elevates mandible “chew”

48. 10.Rotates head, bends head to one side, brings head to upright position 11. Extends head, bends to one side, rotates head

49. Muscles of pectoral girdle 1.Trapezius: A.upper: rotate/raise scapula B.Middle: adduct scapula C.Lower: depress scapula/shoulder 2.Deltoid A.anterior: flex shoulder B.Lateral: abduct shoulder C.Posterior: extend shoulder

50. 3. Rhomboid: major& minor a. raise & Adduct shoulder 4. Levator scapulae: “IDK” a. elevate & adduct shoulder b. flex head to side

51. Pectoralis minor Serratus anterior Muscle that move shoulder girdle 5. Serratus Anterior a.Abducts scapula & rotates 6. Pectoralis Minor a.Draws scapula forward & downward b.elevates ribs

52. Muscles that move Arm 7. Pectoralis Major a. flex, adduct & medially rotate arm 8. Latissimus Dorsi (Lats) a. extend arm b. adduct medially rotate arm c. pulls shoulder down & back

53. “Rotator Cuff” 9. Teres Major: extends, adducts & medially rotates arm 10. Teres Minor*: Rotates arm laterally w/ infraspinatus 11. Infra spinatus: rotates arm laterally 12. Supraspinatus: abducts arm 13. Subscapularis*: medially rotates arm

54. Muscles that move forearm 1. Biceps brachii: a.Flexes forearm b.Supinates hand 2.Brachialis a. flex forearm 3. Brachioradialis a. flex forearm

55. Muscles that move forearm 4.Triceps brachii –A. extend forearm 5. Supinator* a. supinates hand 6. Pronator teres* a. pronates hand 7. Pronator quadratus* a. pronates hand supinator

56. 1.Flexor carpi radialis* a. Flex abduct wrist 2.Flexor carpi ulnaris* a. Flex adduct wrist 3.Palmeris longus* a.Flex wrist 4.Flexor Digitorium 1.Flexes distal phalanges (digits) Superficial muscles that move hand/wrist

57. Superficial muscle that move wrist/hand 5. Extensor carpi radialis* longus & brevis a. extend wrist, abduct hand 6. Extensor carpi ulnaris* a. extend adduct wrist 7. Extensor digitorum* a. extends fingers

58. Muscles of Abdominal Wall Rectus abdominis –flex trunk, –compress abdomen External oblique –both side together compress abdomen –one side, aids back in rotation –one side aids in trunk flexion internal oblique –both side together compress abdomen –one side, aids back in rotation –one side aids in trunk flexion transverse abdominis –both side together compress abdomen –one side, aids back in rotation –one side aids in trunk flexion

59. Muscles of Abdominal Wall 5. intercostal muscles a. depress & elevate ribs for breathing 6. erector spinae extends back Intercostals

60. Muscles that move the Thigh 1.Tensor facia latae a.abducts, b. flexes c.medially rotates thigh 2.Gluteus maximus a.Extends thigh 3.gluteus medius a.abducts b.medially rotates thigh 4.adductor longus a.adducts, b. flexes, c. laterally rotates thigh 5.adductor magnus a.adducts b.anterior portion flexes c.posterior portion extends 6.gracilis a.adducts b.flexes c.medial rotation

61. Muscle that move the thigh 5. adductor magnus a.adducts b.anterior portion flexes c.posterior portion extends 6. gracilis a.adducts b.flexes c.medial rotation 7. iliopsoas a.Flexes( primary hip flexor) b.Medial rotation

62. IT band Muscles that move hip/leg 1.Sartorius (basket weaver) a.flex leg & thigh b.abducts & laterally rotates thigh c.rotates leg medially Quadriceps femoris group 1.Rectus femoris*: a.extends knee b.flex hip 2.Vastus lateralis: a. extend knee 3.Vastus medialis: a. extend knee 4.Vastus intermedius*: a. extend knee

63. Muscles that move the leg Hamstring group* 1.Biceps femoris*: a.flex knee b.extend thigh c.rotates knee laterally 2.Semitendonosis: a.flex knee b.extends thigh c.more superficial w/ long tendon 3. Semimenbranosis: a. flex knee b. extends thigh c. deep to semitendonosis d. broad tendon

64. Muscles that Move the Foot and Toes 1.Anterior a.Tibialis anterior a.Dorsi flex b.Inversion b.Extensor digitorum longus a.Dorsi flexion b.eversion 2.Posterior a.gastrocnemius* 2 joint muscle a.plantar flex foot b.flexion of knee b.soleus a.plantar flex foot c.flexor digitorum longus a.curl toes 2-5 b.plantar flexion c.inversion foot

65. Muscles that Move the Foot and Toes 1.Lateral a.peroneus longus a.plantar flexion b.eversion foot c.support arch b.peroneus brevis a.plantar flexion b.eversion foot c.peronius tertius a.dorsi flexion b.eversion foot