Joints Articulations Where 2 or more bones connect

Reason for Joints  Connect bones oProvide Support oMake them secure  Allow for movement in most cases  Hyoid only bone that doesn’t connect with another bone oAnchors tongue

3 Types of Joints Classified by how much movement they allow

Synarthroses  Connective fibers grow between the bones  Structurally Strong  Suture Line “show” joint oSkull oPelvis  Fibrous Joints oTib / Fib oRadius / Ulna  Teeth No Movement

Skull Suture Joint Development

Amphiarthroses  Cartilage Disc connects the bones  Carry a lot of weight  Symphysis pubis joint  Vertebral joints oAllows for varied movement oAbsorb force oDiscs filled with a gel  Ribs to Sternum Slight Movement

Diarthroses  Capable of many types of Movements oSome just one movement (two directions) Knee - 2Knee - 2 oSome joints capable of many directions Elbow - 4Elbow - 4 Ankle – 6Ankle – 6 Wrist – 7Wrist – 7  Synovial Joints Free Movement

Structure of Synovial Joints  Joint Capsule oFits over the ends of two bones like a sleeve  Ligaments oConnect two bones together  Articular Cartilage oCushion bone ends oreduce friction  Synovial membrane oLubricating fluid

Types of Diarthroses  Ball and Socket oShoulder & Hip  Hinge oElbow & Fingers  Pivot oAtlas/Axis (C1 & C2) oRadius/Ulna

Types of Diarthroses  Saddle oCarpometacarpal joint of the thumb  Gliding oSuperior & inferior articulating surfaces of vertebrae  Ellipsoid / Condyloid oWrist

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