Joints connect bones and allow movement. They are classified structurally as fibrous, cartilaginous, or synovial, and functionally as immovable, slight movement, or free movement. Synovial joints have articular cartilage, a joint cavity, a joint capsule, synovial fluid, and ligaments. They allow gliding and angular movements like flexion, extension, abduction, adduction, and circumduction. Common synovial joints are plane, hinge, pivot, condyloid, and ball-and-socket joints. Common joint injuries are sprains and subluxations, while common joint issues are bursitis, tendonitis, and the degenerative diseases osteoarthritis and rheumatoid

1. Joints Chapter 8

2. Joint Classification Joints (AKA articulations) are sites where 2 or more bones meet. Classified by structure and function.

3. Structural Classification Fibrous Cartilaginous Synovial

4. Functional Classification Based on amount of movement Synarthroses – immovable Amphiarthroses – slight movement Diarthroses – free movement

5. Synovial Joints Bones are separated by fluid-containing cavities Most joints of the body 5 Structural Features: Articular cartilage Joint (synovial) cavity Articular capsule Synovial fluid Reinforcing ligaments

7. Synovial joints (con’t) Bursae – flat, fibrous sacs lined with synovial membrane, containing synovial fluid Movements Gliding Angular

9. Angular Movements: Flexion – bending that decreases angle of joint

10. Extension: bending that increases the angle of the joint

11. Abduction: moving away from midline Adduction: moving toward the midline Circumduction: distal end of limbs move in circles

13. Types of Synovial Joints Plane Hinge Pivot Condyloid Saddle Ball-and-Socket

16. Joint Injuries Sprain Ligaments reinforcing joint are stretched or torn Painful Severe sprains may need surgery Sublaxation Partial dislocation of a joint

18. Inflammation of Joints Bursitis Inflammation of bursa Usually caused by a blow or friction Tendonitis Inflammation of tendons Usually caused by overuse

19. Degenerative Disease Arthritis Osteoarthritis (OA) – wear and tear of joints Rheumatoid – immune system attacks own tissues

20. Clinical Terms Chapters 6 – 8 Achondroplasia Osteosarcoma Traction Chiropractic Clubfoot Orthopedist Spina befida Arthrology Synovitis