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Joint. the movable or fixed place or part where two bones of a skeleton join. The Joints. Fibrous
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Joint • the movable or fixed place or part where two bones of a skeleton join.
The Joints • Fibrous • Fibrous joints connect bones without allowing any movement. The bones of your skull and pelvis are held together by fibrous joints. The union of the spinous processes and vertebrae are fibrous joints.
The Joints • Cartilaginous • Cartilaginous joints are joints in which the bones are attached by cartilage. These joints allow for only a little movment, such as in the spine or ribs.
The Joints • Synovial • Synovial joints allow for much more movement than cartilaginous joints. Cavities between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid.
III. Types of movement • Flexion • Extension • Rotation • Abduction • Adduction • Circumduction
Flexion • a bending movement around a joint in a limb (as the knee or elbow) that decreases the angle between the bones of the limb at the joint
Extension • an unbending movement around a joint in a limb (as the knee or elbow) that increases the angle between the bones of the limb at the joint
Rotation • turning around as on an axis
Abduction • To draw away from the midline of the body or from an adjacent part or limb
Adduction • moving of a body part toward the central axis of the body
Circumduction • movement of a limb or extremity so that the distal end describes a circle while the proximal end remains fixed
Movement Around Axes • Nonaxial • Uniaxial • Biaxial • Multiaxial
Nonaxial • Bone movement that is not around on an axis plane joint bones slide past each other. Midcarpal and midtarsal joints are gliding joints
Uniaxial • the movements (flexion/extension) are all in one plane and around one axis, the joints are uniaxial
Biaxial • Since bones can move in both planes: side to side and back and forth movements the joints are biaxial
Multiaxial • The movements are allowed in all axes and planes: flexion/extension, adduction/abduction, circumduction and rotation. These joints are multiaxial. http://www.shockfamily.net/skeleton/BALLSOCK.MOV
Muscles, Bones, and Movement Putting the “Operation” in cooperation
Muscles, Bones, and Movement Putting the “Operation” in cooperation
Seven Golden Rules of Muscle Activity • Muscles get smaller as they contract. • Muscles cross at least one joint. • The bulk of the muscle lies proximal to the joint crossed. • All muscles have an insertion and origin. • During contraction, the insertion moves toward the origin. • Muscles only pull; they never push. • Muscles work in pairs.
1.Muscles Get ….. Smaller as they Contract. Try it with your bicep!!!
2.Muscles Cross at Least One Joint • Think drawbridge!! • How can muscles effect movement if they don’t cross a joint? • Where does the bulk of the muscle lie?
All Muscles Have an Insertion and an Origin • Insertion = More moveable attachment • Origin = Less moveable attachment • Insertion is usually distal. • Origin is usually proximal. • Insertion moves toward origin during muscle contraction.
Muscles Only Pull So how do they effect flexion AND extension? Abduction AND Adduction? Because they work in PAIRS!!!! Prime Mover = the muscle with major responsibility for effecting a movement. Antagonist = the opposing muscle responsible for the opposite movement.
Muscles Work in Pairs • A muscle can be both a prime mover and an antagonist. • Name some prime mover-antagonist pairs.
Joint • the movable or fixed place or part where two bones of a skeleton join.
The Joints • Fibrous • Fibrous joints connect bones without allowing any movement. The bones of your skull and pelvis are held together by fibrous joints. The union of the spinous processes and vertebrae are fibrous joints.
The Joints • Cartilaginous • Cartilaginous joints are joints in which the bones are attached by cartilage. These joints allow for only a little movment, such as in the spine or ribs.
The Joints • Synovial • Synovial joints allow for much more movement than cartilaginous joints. Cavities between bones in synovial joints are filled with synovial fluid. This fluid helps lubricate and protect the bones. Bursa sacks contain* the synovial fluid.
Joints • Synovial membrane – Composed of soft areolar connective tissue. • Bursa – flattened fibrous sacs found where bones, tendons, and ligaments come together. Function? • Benefit of synovial fluid??
Benefits of Synovial Fluid • Reduces Friction • Protects the bone
Tendons and Ligaments • Tendons – Attach muscle to bone • Ligaments – Attach bone to bone. • Form follows function???