KINS Unit 3 Lecture 3 Study Guide Joints Arthrology Study of joints Function produce movement Fulcrum or axes of body lever system point where bone segments rotate to Functional classes based on amount of movement Synarthrodial Amphiarthrodial Immovable Slightly movable Surfaces of skull Vertebrae Diarthrodial also classified by of axes of rotation Freely movable also have joint cavity Hip knee shoulder Structural classes parallels functional classification 1 Fibrous joints Fastened tightly by thin layer of fibrous CT a Bones in close contact no motion of very slight b 3 Types of fibrous joints 1 Sutures CT fibers completely fill in between bones Only flat bones in skull 2 Syndesmosis Bones bound by cord or sheet of fibrous CT 3 Gomphosis Articulation between tooth and bony socket Teeth fastened to bone by thin periodontal ligaments 2 Cartilaginous joints bones connected by hyaline or fibrocartilage a Two types Synchondrosis Bones united by hyaline cartilage E g Temporary epiphyseal disk first rib manubrium Symphysis Articular cartilage attached to fibrocartilage disk E g Symphysis pubis intervertebral joint Neither Fibrous nor Cartilaginous joints have joint cavities 3 Synovial joints bones separated by fluid filled joint cavity most joints a Freely movable Diarthrodial b Structure 1 Joint capsule of capsular ligament Loose flexible sleeve or envelope o Dense irregular CT that binds bones together but flexible enough to allow movement Articular cartilage o Hyaline cartilage covers articulating surfaces reduces friction prevents wear and tear on bone ends 2 Synovial membrane Loose CT Lines interior joint surface except articular cartilage Secretes synovial fluid o Thick slippery fluid that lubricates joints in order to decrease friction o Functions as hydraulic shock absorber 3 Articular discs fibrocartilage discs between bones 4 Glenoid or acetabulum labrum lip of fibrocartilage Shock absorbers More stable joint 5 Ligaments Bind the joint together more stable Inside outside joint capsule 6 Bursae and tendon sheaths Fluid filled sacs synovial fluid Minimize friction and act as cushion between ligaments tendons muscles skin bones Summary Structures materials that protect bones in the joint 1 Articular cartilage 2 Articular discs 3 Synovial fluid 4 Bursae Structures that influence joint stability 1 Tightness of joint capsule ligaments 2 Fit of the articulating surfaces articular discs Glenoid Acetabular labrums bone shapes Structures that influence movement capability flexibility of joints 1 Shape of the articulating surfaces 2 Tightness of joint capsule ligaments 3 Bulk of the adjacent tissue 4 Tendons muscles which cross 2 joints Cannot have maximum stability maximum ROM at the same time Muscular System part 1 Myology study of muscular system Nearly all physical functions involve muscle activity Functions 1 Movement a Movement of entire body from place to place b Manipulation of body parts c Moving materials into out of within body Respiration air Circulation blood digestion food along digestive track 2 Posture Partial contraction of muscles to oppose downward pull of gravity a Anti gravity muscles Neck flexors abdominals spine extensors illiopsoas gluteus maximus quads hamstrings gastrocnemius soleus 3 Joint stability muscles around shoulder and knee regions contribute to stability 4 Heat production by product of muscle contraction very active numerous Temperature homeostasis for the body Tissue types 1 Epithelial 2 Connective 3 Nervous 4 Muscle a 3 types of muscle cells or muscle fibers classified by Location appearance nervous control Location 1 Skeletal Appearance Striated Nervous Control Voluntary 2 Visceral smooth Non striated smooth Involuntary 3 Cardiac Striated Involuntary Properties or Functional characteristics 1 Irritability or excitability Respond to a stimulus Move whole body or body parts Walls of internal organs Heart muscle a 2nd most highly irritable tissue nervous tissue 1st b Initiate contraction very rapidly after signaled to do so 2 Contractility ability to produce tension between its ends exert pulling force a MOST DISTINGUISHING CHARACTERISTIC b Property allows muscle to cause movement 3 Extensibility Allows outside force to stretch muscle 4 Elasticity Ability to return to normal length after being stretched Extensibility elasticity offer protection by allowing muscle to be subjected to certain stresses and strains without damage Skeletal muscle Muscle prefixes o Myo muscle o Mys o Sarco flesh Muscle fiber muscle cell called fiber due to shape Long narrow Fibers do not run entire length of bone Fiber s force transmitted to CT sheaths which pull on bones Each fiber has many thread like structures called myofibrils Located in fiber s sarcoplasm muscle cell cytoplasm Sarcolemma Plasma membrane of muscle fiber Endomysium Thin layer of fine areolar CT surrounding each muscle fiber fascicle Whole muscle Anchored to sarcolemma Muscle fibers organized into bundles called fascicles as many as 150 per Held together by CT sheath called perimysium collagenic in nature Groups of fascicles bundled together Epimysium Dense fibrous CT sheath surrounding entire muscle becomes continuous with deep fascia Muscle tissue Belly Part which contains the fibers fascicles Attachments muscles attach directly or indirectly to bone or other tissue 1 Direct fleshy attachment Epimysium of muscle fused to periosteum or perichondrium of cartilage e g Tibialis Posterior 2 Indirect attachment towards end of muscle fibers disappear leaving CT sheaths Endo peri and epimysia become intertwined a Attaches to bone fascia or to a Raphe seam of fibrous tissue b CT takes one of two shapes 1 Tendon CT structure narrow and cord like 2 Aponeurosis CT broad and flat In bone o Tendons aponeuroses intertwine with Fibers of Sharpey for a stronger attachment o Intertwining CT sheaths Fibers of Shapey distributes pull of muscle over large area o Tendons transmit relatively large forces to very small areas of attachment