1. Skeletal System Articulations

2. Articulation (joint): a point of contact between bones. Some allow movement, others are immovable (sutures). Most joints allow considerable movement as a result of muscle contractions.

3. Classification of Joints Categories –Structural (by connective tissue or fluid) Fibrous Cartilaginous Synovial –Functional Synarthrosas Amphiarthrosis diarthrosis Table 9-1 pg 256 classifies Each joint. Refer to it Often.

4. Fibrous Joints (Synarthroses) Fibrous joints fit close. Connective tissue permit limited movement; most joints are fixed (immovable.) 2 sub types –Syndesmoses –Sutures –Gomphoses

5. Syndesmoses Joints in which fibrous tissue connect two bones. Some movement possible because of ligament flexibility. –Example: Distal ends of radius and ulna

6. Sutures Found only in skull. Thin layer of fibrous tissue between bones. Immovable.

7. Gomphoses Unique joints between root of teeth and mandible or maxilla.

8. Cartilaginous Joints (Amphiarthrosis) Bones joined by hyaline or fibrocartilage. Hyaline joints- Synchondroses Fibrocartilage joints- symphyses Joints are slightly movable in certain circumstances.

9. Synchondroses Hyaline cartilage between articulating bones Examples: Articulation between first rib and sternum.

10. Symphyses Fibrocartilage pads bones Slight movement possible when pressure is applied. Example: Symphysis pubis opens pelvis during childbirth. Other examples of symphysis joints: vertebrae.

11. Synovial Joints (diarthroses) Freely movable. A majority of joints are synovial. Ex: knee, hip Subcatagories: –Uniaxial –Biaxial –Muliaxial

12. Flashcards: Will be used during first dissection Requirements: –Front of card Name of the joint type. –Back of card Definition of joint Example of the joint. Picture of the joint Required Cards: –Synarthroses: Syndesmoses –Synarthroses: Sutures –Synarthroses: Gomphoses –Amphiarthrosis: Synchondroses –Amphiarthrosis: symphyses –Diarthroses Diarthroses These joints are freely Movable. Examples: Hip & knee

13. Types of Synovial Joints (Diarthroses) 3 main groups: –Uniaxial Hinge Pivot –Biaxial Saddle Condyloid –Multiaxial Ball and socket Gliding

14. Uniaxial Joints Synovial joints that permit movement around one axis and in one plane. Hinge: Hinge shape; only back and force movement. –Example: Knee; ulna & humerus Pivot: Projection articulates with a ring or notch of another bone. –Example: 2 nd & 1 st cervical vertibrae.

16. Biaxial Joints Movement around 2 perpendicular axes in two perpendicular planes. Saddle: Joint resembles a saddle. –Example: Thumbs are the only 2 saddle joints in the body. Condyloid: Where a condyle (rounded projection) fits into a socket. –Example: Occipital condyles & cervical vertebrae; Distal end of radius into carpal bones.

17. Saddle Condyloid Condyle

18. Multiaxial Joint Joints that allow movement around multiple axes & around multiple planes. Ball & socket: Most moveable joint; ball shaped head fits into circular depression. –Example: Should; hip Gliding joints: Flat articulating surfaces that allow limited gliding along various axes; least moveable synovial joint. –Example: Vertebrae; carpals & tarsals.

19. Gliding Ball & Socket

20. Flashcards: Will be used during first dissection Requirements: –Front of card Name of the joint type. –Back of card Definition of joint Example of the joint. Picture of the joint Required Cards: –Uniaxial: Hinge –Uniaxial: Pivot –Biaxial: Saddle –Biaxial: Condyloid –Multiaxial: Ball & socket –Multiaxial: Gliding Uniaxial: Hinge Only back and force movement Examples: knee

21. Structure of synovial joints Joint capsule Synovial Membrane Articular cartilage Joint cavity Menisci (articular Disks) Ligaments Bursae

22. Joint Capsule Sleeve-like extension of periosteum (bone membrane) Forms a casing around ends of bones, binding them.

23. Synovial Membrane Membrane that lines joint capsule and attaches to margins of articular cartilage. Secretes synovial fluid.

24. Articular Cartilage Thin layer of hyaline cartilage. Cushions articular (connecting) ends of bone.

25. Joint cavity Space between articulating bones. More space  More movement.

26. Menisci (articulating disks) Pads of fibrocartilage between articulating ends of some diarthroses. Usually divide joint cavity into two separate spaces. Knee joint has 2 menisci.

27. Ligaments Strong cords of dense fibrous tissue. Keep bones together.

28. Bursae Closed pillow like structure. Filled with synovial fluid. Cushion joint and facilitate movement of tendons. Bursitis- Inflammation of bursae.

29. Disorders of the Joints Osteoarthritis: Degenerative joint disease; wear & tear of articular cartilage. Cartilage thins, bony spurs form at articulations, ligaments calcify. Symptoms: stiffness, pain, limited mobility.

30. Disorders of the Joints Traumatic Injuries: –Dislocations- damages nerve & blood vessels. –Damage to cartilage- tears produce edema, pain, instability, & limited motion. –Sprain- injury to ligaments surrounding a joint, disrupting synovial membrane. Bruising and swelling may result from ruptured blood vessels.

31. Disorders of the Joints Arthritis: inflammatory joint disease. Inflammation of synovial membrane, destruction of cartilage, erosion of bone. Can be crippling and cause deformities. –Juvenile arthritis: Onset during childhood. –Gouty arthritis: Arthritis caused by a metabolic disorder- excess uric acid deposit into synovial fluid.