Today and Wednesday – muscles!

1. Today and Wednesday – muscles! • how muscles work – in general • muscles that move the mandible • abdominal wall muscles • anterior and posterior • inferior and superior • inguinal hernia’s • muscles that move the humerus and scapula • rotator cuff tears, impingement syndrome • muscles that move the femur • sprains, strains and “Charley horse” • muscles that move the foot • shin splints, anterior compartment syndrome • Achilles tendon injuries

2. skeletal cardiac smooth

3. Connective tissue wrappings of skeletal muscle Tendon Deep fascia 1 muscle fiber = 1 muscle cell Muscle cells are multinucleated Epimysium Epi = upon, above Perimysium Peri = around Endomysium Endo = within Working out Atrophy & aging Steroids Myo, mys = muscle

4. Muscle attachments Origins Origins Bellies Insertion Direct vs Indirect attachment Ligaments: bone to bone Tendons: muscle to bone Insertion

5. Muscle to muscle via tendon sheet Muscle to skin Aponeurosis

6. Neuromuscular junction Synaptic vesicles containing Ach (acetylcholine) • Neurotoxins • botulism • curare • tetanus toxin Motor end plate Calcium + ATP = muscle contraction Low blood Ca and muscle

7. Attachments: • Proximal • Distal • Direct • Indirect • Muscle actions: • agonist • antagonist • synergist • fixator Biceps brachii Brachialis Triceps brachii

8. Extending your knee • Extend your knee a few times • Where are the agonist muscles that extend your knee? • Which joint do they cross? • When you extend you knee, where are the antagonist muscles located?

9. Quadriceps = agonists Hamstrings = antagonists

10. Moving the mandible Mandibular fossa • Depress & elevate • Medial & lateral excursion • Protraction & retraction

11. Muscles that move the mandible Temporalis Masseter • attachments • actions

12. Lateral pterygoid Medial pterygoid • attachments • actions

13. Depress mandible • gravity • digastric muscle • geniohyoid & mylohyoid • when hyoid is fixed

14. Temporalis massater Medial pterygoid Lateral pterygoid Mylohyoid Digastric

15. Those flashy “core” muscles Overdeveloped Pectoralis major External oblique Rectus abdominus

16. Muscles that move (and protect) the abdomen/trunk Internal oblique Transversus abdominis Rectus abdominis • Attachments • Actions External oblique

17. Linea alba B A C Rectus sheath (aponeurosis) D

18. Abdominal wall • abdominal muscles • back muscles • quadratus lumborum • Psoas (iliopsoas) • diaphragm • pelvic diaphragm • “holes” in the wall • hernia (hiatal) • congenital or acquired

19. Parietal peritoneum Inguinal canal – men & women intestines scrotum Inguinal hernia Spermatic cord

20. 1. Name the 4 layers of connective tissue that wrap • around skeletal muscles. • 2. Which ones are continuous with a tendon? • 3. Botox (botulinum toxin) works by blocking the • release of ACh at the neuromuscular junction. • How does this help with: • crossed eyes • uncontrolled blinking • those pesky forehead wrinkles

21. Muscle that move the humerus and scapula • Location of shoulder muscles • Which joints do these muscles cross?

22. 3. What movements do these muscle perform?

23. Deltoid • attachments • actions (on humerus) • abduct (lateral fibers) • flex, medially rotate (anterior fibers) • extend, laterally rotate (posterior fibers)

24. attachments • actions • flexion (agonist) • adduction • medial rotation • elevate ribs

25. 4 Rotator cuff muscles • Supraspinatus • abduct • Infraspinatus • Extend • Laterally rotate • Teres minor • adduct • laterally rotate • Subscapularis • medially rotate

26. Scapula movers & stabilizers • Levator scapulae • elevate scapula • flex neck • Trapezius • elevate, rotate upward (S) • retract (M) • depress (I) • extend neck • flex laterally (one trap) • Rhomboids • retract • elevate • fix scapula • rotate downward

27. Trapezius Rhomboids Deltoid Teres major Triceps Latissimus dorsi Supraspinatus Infraspinatus Subscapularis Levator scapulae

28. Impingement syndrome Rotator cuff tears

30. Muscles that move the femur 1. Location of hip and thigh muscles 2. Which joints do these muscles cross?

31. 3. What kind of movements do these muscle perform?

32. Iliopsoas • flex hip • Lateral rotators • piriformis • obturator externus • Adductors • adduct femur • flex hip • flex knee • (lateral rotation) Groin pull

33. Tensor • Fasciae • Latae (TFL) • flex • abduct • med. rot • Rectus • Femoris • flex hip • extend knee • Vastus lateralis • vastus intermedius • Vastus medialis • extend knee Patellar tendon • Charley horse • patella tracking

34. Tensor Fasciae Latae • flex femur • abducts femur • medially rotates femur • stabilizes knee G. Maximus Iliotibial Band (IT band)

35. G. minimus G. Medius piriformis G. Maximus Gluts: extend, abduct, laterally rotates femur Piriformis: abduct, laterally rotates femur

36. Hamstring group: flex knee, extend hip Muscle strains from quick extensions

37. Muscle compartments of the thigh Anterior anterior medial posterior Posterior • Compartments: • each wrapped with deep fasciae • each has own nerve & blood supply • compartment syndrome

39. Iliopsoas TFL Sartorius Adductors quads Glut max & medius hamstrings Piriformis Sciatic nerve

40. Attachments of the gastrocnemius • Attachments of the soleus • Actions of the gastrocnemius • Flex the knee • Plantarflex the foot • Actions of the soleus • Plantarflex the foot gastrocnemius Achilles tendon Ruptured Achilles tendon Pulled calf muscle calcaneus

41. Tibialis Anterior • Attachments • Actions • Dorsiflex ankle • Invert foot • Support arch Tibialis anterior Shin splints Compartment syndrome

42. Agonist of elbow extension? • 2. A strained biceps brachii would result in pain when ____. • 3. When viscera protrude through a weak point in the diaphragm, • what is that condition called (be specific). • 4. In a male, what passes through the inguinal canal? • 5. Name one muscle that moves the mandible laterally.