MECHANICS OF MOVEMENT

Transcription

1 MECHANICS OF MOVEMENT Tissues and Structures Involved Muscle Nerve Bone Cartilage What are Tendons? Role of Joints Mechanics of Joints Making it all work

2 Nerve and Muscle--the Motor Unit Skeletal muscles controlled voluntarily by brain: Brain spinal cord motor neuron muscle Motor Unit = one motor neuron + the muscle cells it controls Fig. 14.6, M&M

3 Neuro-Muscular Junction Where the motor neuron connects with the muscle fibers Fig. 14.5, M&M

4 See also photo in Fig from M&M to see capillaries around muscle cells

5 HOW MOVEMENT HAPPENS: Muscles Pull on Tendons to Move Bones at Connections called Joints or Articulations

6 Tendon Regular connective tissue Musculo-skeletal connections Muscle to bone Purpose is to move bone Fig. 4.15f, M&M

7 Tendons Various shapes Typical is cord-like tendon of biceps Sheaths are common- aponeuroses Fig. 10.3, M&M

8 Aponeuroses Sheets of tendons that connect muscle to bone

9 Ligaments Ligaments connect bone-to-bone or reinforce joints E.g. knee ligaments Fig. 9.12, M&M

10 Joints or Articulations Connections between bones Usually, but not always allow for movement Formed from various connective tissues Fibrous Cartilaginous Synovial (most complex--typical limb joints)

11 Fibrous joints Suture Bones tightly bound by minimal fiber Only found in skull Soft spots = developing sutures in skull called fontanels Fig. 9.1 a, M&M

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13 Fibrous joints Syndemoses Bones connected by ligaments Some distance between bones E.g. tibiofibular ligament, interosseous membrane of radius/ulna Fig. 9.1 b, M&M Fig. 8.4, M&M

14 High Ankle Sprain

15 Fibrous joints Gomphoses Peg in socket joint Only found in teeth/alveoli Fig. 9.1 c, M&M

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17 Cartilaginous Joints Hyaline Cartilage Fig. 9.2, M&M Epiphyseal growth plates Costal cartilage-sternum Also called synchondroses

18 Cartilaginous Joints Fibrocartilage pelvic girdle, intervertebral disks Also called Smyphysis

19 Synovial Joints Most common joints in body Most mobile joints Have Articular surfaces on bone with hyaline cartilage Completely enclosed joint capsule formed from ligamentous connective tissue Synovial fluid within capsule lubricates joint Some have meniscus or articular disc(e.g. knee, jaw joint)

20 Also see Fig. 9.3, M&M

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24 Synovial Joint Shape Types Plane joints--intercarpal joints Hinge joints--elbow,ankle, inter-phalangeal Pivot joints--radio-ulnar joint Condyloid joints (egg into oval)--metacarpo-phalangeal Saddle joints--carpo-metacarpal joint of thumb Ball-and-socket--hip, shoulder The type of joint, in part, determines the range and direction of movement

25 Plane Joints Gliding joints Between flat surfaces to permit gliding motions

26 Hinge Joints Convex bone fits into a concave bone Hinge movement like a door opening

27 Pivot Joints One bone forms a cylinder, other bone forms a ring, allows a pivot motion

28 Condyloid Joint Oval shaped end of one bone fits into empty space of another bone Back and forth + circular movement

29 Saddle Joint Convex part of one bone fits into concave part of another Back and forth, side to side, some pivot

30 Ball in Socket Joint Ball shape fits into socket shape Full range of motion

31 Fig. 9.9, M&M

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37 Knee Replacement

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39 ACL Reconstruction

40 Tommy John Surgery

41 Skit Instructions Groups of Fill in the joint cheat sheet document 2. Write a skit on a topic of your choice (see example topics) 3. In your skit, display all of the types of movements at synovial joints i. For example, a character in your skit could throw a baseball, demonstrating a circumduction movement at a ball and socket joint 4. While you perform, your audience will be taking notes to make things easier for them, make sure that the actor demonstrating the movement is the one who is talking at that moment (make it obvious) 5. Your group will also prepare one paper identifying how you will demonstrate each movement type and the type of joint it is occurring at.