1. Chapter 8Joints

2. Joints Also called articulations; place where two or more bones meet Function- Hold skeleton together and give it mobility

3. Classifications of Joints Structural Functional

4. Functional: Classification of Joints Synarthroses- no movement; all fibrous joints in this category like sutures, gomphoses (teeth), tibiofibular ligament Amphiarthroses- slight movement; includes intervertebral joints and symphysis pubis Diarthroses- freely mobile; includes remainder of joints

5. Structural Classification 1. Fibrous  no joint cavity; bones joined by fibrous tissue; almost all are immoveable Sutures Syndesmoses Gomphosis (functionally Synarthroses)

7. Structural Con’t 2. Cartilaginous  no joint cavity; motion ranges from rigid to slightly mobile Synchondroses Symphyses (Functionally Amphiarthroses)

9. Structural Con’t 3. Synovial  has a joint cavity, freely mobile (Functionally Diarthroses) Almost all other joints of the body are in this category

10. Quiz Picture p. 220

11. Characteristics of Synovial Joint Articular Capsule Articular Cartilage Joint Cavity Synovial Fluid Reinforcing Ligaments

13. Bursae & Tendon Sheaths Bursae- flattened sacs lined with synovial membrane; filled with synovial fluid Tendon sheaths- an elongated bursae that wraps completely around a tendon Fat Pads- adipose tissue pads in joint; cushions joint Function- reduce friction between structures

14. Quiz Picture p.222

15. Stability of Synovial Joints Articular Surfaces- only a minor role Ligaments- only a minor role Muscle Tendons- most important stabilizing force at a joint

17. Types of Movement at Synovial Joints Nonaxial- slipping movements only Uniaxial- movement in only 1 plane Biaxial- movement in 2 planes Multiaxial- movement in 3 planes

18. Why Movement Occurs Each skeletal muscle is attached in at least 2 places to bone or connective tissue. Movement occurs with contraction of muscle across joints. Origin-attachment to immobile bone. Insertion-attachment to mobile bone

19. Types of Movement Gliding (nonaxial)- bones slip past each other; no angular movement occurs Movement between carpals, tarsals, and articular processes of vertebrae

20. Types of Movement Angular- several different types –Flexion- decrease the angle of a joint –Extension- increase the angle of a joint –Dorsiflexion (foot)- foot toward head –Plantarflexion (foot)- foot away from head –ABduction- limb away from midline –ADduction- limb toward midline

23. Types of Movement - Circumduction- limb traces a cone/circle in space - Rotation- turning a bone around its own long axis

24. Special Types Movement Suppination- palm up Pronation- palm down Inversion- foot turns in (sprained ankle) Eversion- foot turns out

25. Special Types Movement Protraction- bone forced forward Retraction- bone forced backward Elevation- lift superiorly Depression- drop inferiorly Opposition- thumb to tips of fingers on same hand

28. Types of Synovial Joints Plane Joints- flat articular surfaces; allow only gliding movements; only nonaxial joints; intercarpal, intertarsal, and intervertebral joints Hinge Joints- the rounded end of one bone fits into a space on another bone; uniaxial joint; elbow and interphalangeal joints

29. Types of Synovial Joints Condyloid Joints- the articulating surfaces are oval; biaxial joint movement; radiocarpal and metaphalangeal joints are examples Saddle Joints- articular surfaces have concave and convex areas; biaxial movement; carpometacarpal joints of thumbs

30. Types of Synovial Joints Pivot Joints- the rounded end of one bone protrudes into an opening of another or into a ligament Ball and Socket Joints- only two in the body; the shoulder and the hip; freely mobile; most versatile joints

33. Knee Joint Largest, most complex joint of body articular capsule sides and back of joint highly susceptible to injuries due to carrying body weight horizontal force injuries are the worst

36. Shoulder One of only 2 ball and socket joints in the body humeral head fits into glenoid cavity lots of flexibility with a loss of stability location of the rotator cuff

39. Hip ball and socket joints in the body femoral head fits into the deep acetabulum of the coxal bone lots of stability but not as much flexibility as the shoulder

41. Elbow hinge joints in the body uniaxial movement joint contains fat pad

43. Injuries Torn ligaments Bursitis Tendonitis

44. Arthritis Osteoarthritis – most common Rheumatoid - autoimmune Gouty – diet, uric acid

52. Rheumatoid Arthritis