General Muscle, Bone, & Articulation Anatomy Coach Ryan

Skeletal System

Bones Protect organs Support/Framework Provide Movement (work with muscles) Store minerals Produce blood cells 2 skeletons Axial (spine, thorax, and skull Appendicular (bones of the extremities)

Anatomical Characteristics of Bone Dense connective tissue consisting of bone cells (osteocytes) that are filled in a matrix, which consists of an intercellular material. Compact (hard) tissue – outer surface, tunneled by a marrow cavity Cancellous (spongy) bone – inner aspect composed of a more porous tissue Contains a network of blood and lymphatic vessels Periosteum – tissue that covers a bone and contains the blood supply to the bone

Cont… Epiphysis – growth plate located at the ends of a long bone Bone types Long (femur) Short (metacarpal) Flat (scapula) Irregular (vertebra) Osteoblasts – bone-producing cells (new) Osteoclasts – cells that resorb bone (break up old bone)

Marrow Red Marrow – RBC’s, WBC’s and platelets Yellow Marrow – WBC’s

GROWTH PLATE

Cartilage Covers the ends of long bones and can be found between bones Functions: Join structures (ribs and sternum) Absorb shock Permit smooth bone movement 3 types Hyaline or articular (nasal septum, articular ends of bones of synovial joints) Fibrous (vertebral discs, menisci) Elastic (external ear)

Joints Three classifications of joints: Synovial, Fibrous, and Cartilaginous Ligaments – connective tissue joining bone to bone Synovial (Diarthrodial) – Have fantastic mobility and consist of a joint capsule Consists of Joint capsule lined with a synovial membrane Hyaline cartilage Ligaments

Types of Synovial Joints Ball and Socket – allow all possible movement Shoulder and hip joints Hinge – allow only flexion and extension Elbow and knee Pivot – permits rotation around an axis Cervical atlas and axis, proximal ends of radius and ulna Ellipsoidal – have an elliptical convex head and a concave socket wrist

Cont… Saddle – reciprocally concavo-convex Carpometacarpal joint of the thumb Gliding – allow a small amount of gliding back and forth and sideways Joints between the carpal and tarsal bones, joints between vertebrae

Fibrous (Synarthrodial) Joints Held by connective tissue Immovable E.g. Bones of the skull. Between tibia and fibula

Cartilaginous (Ampiarthrodial) Joints Cartilage attaching two bones together E.g. Where the ribs meet the sternum

Muscles (mm) Cardiac – heart Three types: Smooth – internal organs Cardiac – heart Skeletal – attached to skeleton responsible for movement TYPE I – “Slow Twitch” TYPE II – “Fast Twitch”

MUSCLE CONTRACTIONS AGONIST - Muscles that carry out a given action. ANTAGONISTS – mm that carry out the opposing action. ISOTONIC – mm contraction, tension remains unchanged and the muscle's length changes. CONCENTRIC – mm shortens. ECCENTRIC – mm lengthens. ISOMETRIC – mm stays the same length.

Structure of a Skeletal Muscle

Muscles Composed of contractile cells or fibers Myofibrils are surrounded by the endomysium Fiber bundles are surrounded by the perimysium The entire muscle is surrounded by the epimysium Tendon – attaches muscle to bone Aponeurosis - connective tissue that attaches to other muscles

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