1	BASIC HISTOLOGY OF SYNOVIAL JOINTS
2	JOINTS IN GENERAL For movement and positioning Wide range of motions Often limited Arrangement and alignment of parts have to be protected Exogenous materials Mechanical wear Physical injury
3	ANATOMIC BONES Hard “shell” of compact bone Internal Marrow Spaces Periosteum Articular Cartilage No perichondrium
4	BLOOD SUPPLY IN A BONE Cartilage is AVASCULAR Only limited repair capability Synovium highly vascularized Periosteum highly vascularized Joint space not isolated from immune system
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6	SYNOVIAL JOINTS SEALED SPACES Articulated ends of bones Cartilage Grades into synovium and periosteum Joint Capsule Dense CT Continuous with periosteum Synovium Special secretory lining of cavity
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8	JOINT CAPSULE
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10	SYNOVIUM Inner layer of the joint capsule Discontinuous CT Not a true epithelial sheet CT directly exposed to fluid Fibroblast-like cells Macrophages Highly vascular Fluid similar to interstitial fluid in general Blood transudate
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15	…THE JOINT SPACE IS ACCESSIBLE TO THE IMMUNE SYSTEM
16	THERE ARE NASTIES OUT THERE…
17	SO KEEP IT CLEAN!
18	CARDINAL SIGNS
19	RESPONSES TO INFLAMMATION:
20	INFLAMMATORY EXUDATE
21	TRAUMATIC INJURIES Due to mechanical stress Compressive and torsional forces Damaged cartilage an inflammatory stimulus
22	WHAT GOES UP…
23	…MUST COME DOWN
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