1. Think about it:
John bent over to pick up a dime. What bones do you think is involved in this movement?
his hip/pelvic bones
at his patella (knee cap), and
between his index finger and thumb?

2. Think about it too:
You have a big itch in the middle of his back. Try to scratch your back without bending your elbow.
Try to run away from a charging leopard without bending you knees.
How does this feel? Are you able to successfully move your body?

3. Joints Notes
Page 34

4. Learning Objectives
To describe the different types of joints and skeletal movement they allow.

5. I. What are Joints?
Bones are hard and cannot bend, so how can our bodies twist, bend, and rotate?
Joints (or articulations) are where two or more bones meet or connect to allow movement of the rigid skeletal frame.

6. Tissues Involved at Joints:
Ligaments- tissue that connects bone to bone and helps add to our flexibility.
Cartilage- strong tissue that reduces friction and increases flexibility.
Cushions end of bones so bones don’t rub/grind against each other with skeletal movement.

8. II. Joint Classification:
Structure
Function
1. Fibrous Joints
Bones held together by dense collagen fibers
2.Cartilaginous Joints
Bones held together by cartilage
3. Synovial Joints
Bones held together by ligaments
1. Synarthrosis
Immovable (not movable) Joints
2. Amphiarthrosis
Slightly movable joints
3. Diarthrosis
Freely movable joints

9. 1. Fibrous Joints=Synarthrosis
Immovable Joint= No Movement
The articulating bones are held very close together by dense irregular connective tissue.
Located:
Sutures: bones of skull held together by connective tissue fibers
Between teeth & jaws

10. Three types of fibrous joints: A. Sutures B. Syndesmoses
Occur between bones of the skull.
B. Syndesmoses
Permits slight movement
Interosseous membrane
Between tibia and fibula of the leg
C. Gomphoses
Immovable joint
A cone-shaped peg fits into a socket
Teeth articulation with sockets of the maxilla and mandible

12. 2. Cartilaginous Joints= Amphiarthrosis
Allows little movement
Bones connected by cartilage
Location:
Epiphyseal plates= hyaline cartilage at end of long bones
Ribs & sternum
Pubic symphysis
Intervertebral discs

14. 3. Synovial Joints= Diarthrosis
Allows movement in many directions
Ligaments hold bones together
Bones separated by fluid-containing joint cavity:
A. Synovial fluid reduces friction between cartilages
Lubricates joint
Absorbs shock
B. Menisci (Meniscus): fibrocartilage that partially divides a joint cavity at knee, reduces friction
C. Bursa: flattened sacs containing synovial fluid, located between tendons, ligaments, and bones. Cushions the movement of the body parts.

15. Ligaments and Meniscus (Menisci)
Knee Joint

17. Torn medial meniscus

18. Bursa (fluid-filled sac that cushions between bones & tendons/muscles

19. Types of Synovial Joints

20. III. Types of Synovial Joints
Synovial joints are classified based on type of movement.
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal) – metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

21. Also called a gliding joint
Primarily allows back-and-forth and side-to-side movements
Joints between carpal and tarsal bones

22. III. Types of Synovial Joints
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal) – metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

23. Produces an opening and closing motion like that of a hinged door.
Permits only flexion and extension movement
Knee, elbow, phalanges (fingers)

24. III. Types of Synovial Joints
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal) – metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

25. Surface of one bone articulates with a ring formed partly around another bone
Allows bones to rotate

26. III. Types of Synovial Joints
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal) – Metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

27. The projection of one bone fits into the oval-shaped depression of another bone.
Permits movement in 2 planes= flexion, extension, adduction, abduction, circumduction

28. III. Types of Synovial Joints
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal) – metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

29. Surface of one bone is saddle-shaped and the other bone fits into the saddle.
Thumb
Allows bones to move back and forth and side to side, but have limited rotational ability.

30. III. Types of Synovial Joints
Plane/Gliding – wrist, ankle, vertebrae
Hinge – elbow, knee, fingers and toes
Pivot – neck
Condyloid (ellipsoidal)- metatarsals, metacarpals
Saddle – thumb
Ball-and-socket – shoulder, hip

31. Ball-like surface of one bone fits into a cuplike depression of another bone.
Shoulder and hip
Allows bones to move and rotate in nearly all directions.