1. joint general anatomy.ppt

1  Joint (or articulation)- the junction between two or more bones. With the exception of the hyoid bone, every bone in the body is connected to a joint. There are 230 joints in the body 2 1. Hold the skeletal bones together 2. Allow the skeleton...

1  Joint (or articulation)- the junction between two or more bones. With the exception of the hyoid bone, every bone in the body is connected to a joint. There are 230 joints in the body 2 1. Hold the skeletal bones together 2. Allow the skeleton some flexibility so gross movement can occur 3. Make bone growth possible 3  A site where two or more bones come together 4 Classification by structure Classification by function Joints classified according to Joints classified according to the tissues that lie between the bones: mobility  1. Fibrous joints  1. Synarthroses - bones held together Immovable joints by fibrous connective tissue  2. Cartilagenous  2. Amphiarthrose joints Slightly movable joints - bones held together by cartilage  3. Diarthroses  3. Synovial joints - complex structure Freely movable joints with cartilage and cavities 5  Flexion decreases the angle of a joint  Extension straightens and returns to the anatomical position  Hyperextension = extension beyond 180 degrees 9-6 7 8 9-9  Abduction is movement of a part away from the midline  hyperabduction – raise arm over back or front of head  Adduction is movement towards the midline 9-10 11  Movement on vertical axis  rotation of trunk, thigh, head or arm  Medial rotation turns the bone inwards  Lateral rotation turns the bone outwards 12 Protraction = moving body part forward (anterior movement) in a transverse or horizontal direction Retraction = posterior movement 13 14  The articulating surfaces of the bones are joined by fibrous tissue Examples: The sutures of the skull 15  1. Suture  2. Gomphosis  3. Syndesmosis 16 Immobile joints in the skull -“serrate” wavy lines parieta/frontal bones -“lap”/ “squamous” overlapping temporal/parietal bones -“plane” nonoverlapping Paired maxillary and palatine bones 17 18  where teeth attach to bone 19   Two bones bound by ligament only  interosseus membrane Tibia – fibula at distal end 20 1-Synchondroses 2-Symphysis 21 1-Synchondroses: when bone is joined by hyaline cartilage  between the 1st rib and the manubrium sterni (ONLY the first rib) 22 2-Symphysis: where bones are joined by fibrous cartilage  Between vertebrae  Pubic bone (pelvis) 23  “synovial” joint because the joints are separated by a space (“synovial cavity”= “joint cavity”), where synovial fluid is retained  The cavity of the joint is lined by synovial membrane  Synovial fluid rich in albumin (blood protein) and hyaluronic acid which is produced by the synovial membrane 24  The articular surfaces of the bones are covered by a thin layer of hyaline cartilage called articular cartilage The synovial membrane is protected on the outside by a tough fibrous membrane referred to as the capsule of the joint 25 26  Synovial joints can be classified according to the arrangement of the articular surfaces and the types of movement that are possible.  Types of joints: classification by shape:  1- Ball-and-socket joints  2- Hinge joints  3- Pivot joints  4- Saddle joints  5- Condyloid joints  6- Plane joints  7- Ellipsoid joints 27  1-Ball & Socket joints (hip and shoulder) :  a ball- shaped head of one bone fits into a socketlike concavity of another  This arrangement permits free movements, including flexion, extension, abduction, adduction, medial rotation, lateral rotation, and circumduction. 28 29  2-Hinge joints  Resemble the hinge on a door  so that flexion and extension movements are possible  Examples of these joints are the elbow, knee, and ankle joints 30  3-Pivot joints  a central bony pivot is sur- rounded by a bony– ligamentous ring and  rotation is the only movement possible.  The atlantoaxial and superior radioulnar joints are good examples 31  4-Saddle joints  the articular surface concave and convex  resemble a saddle on a horse’s back.  These joints permit flexion, extension, abduction and adduction.  The best example of this type of joint is the carpometacarpal joint of the thumb 32  5-Condyloid joints  two distinct convex surfaces that articulate with two concave sur- faces.  The movements of flexion, extension, abduction, and adduction are possible together with a small amount of rotation.  The metacarpophalangeal joints are good examples 33  6-Plane joints Bone surface almost flat Bones slide along each other Ex: carpal bone, patella-femur 34 7-Ellipsoid joints an elliptical convex articular surface fits into an elliptical concave articular surface. The movements of flexion, extension, abduction, and adduction can take place, but rotation is impossible. The wrist joint is a good example 35 Other structures present in synovial joints:  1-Tendons: collagen-based connective tissue that hold muscle to bone  2-Ligaments: collagen-based connective tissue that hold bone to bone  3-Labrum: a fibrocartilage ring around the bony cup 36  4-Bursa: fibrous “sac” that holds synovial fluid  They are commonly found close to joints where the skin rubs against underlying bony structures  5-Meniscus: a crescent- shaped fibrocartilaginous structure 37  inflammatory illness of a joint  autoimunne (rheumatic, psoriatic)  septic  gout – storage of crystals of uric acid to the vicinity of a joint http://www.abbottdiagnostics.cz/nove-produkty/ rok-2009/imunoanalyza/architect-anti-ccp.html http://www.mojemedunka.cz/clanek.aspx/ medunka-informuje/clanek/proc-jsme-nemocni-- cast-xxxxi 38 - An autoimmune disease 39 - Bone degeneration due to old age 40  inflammation of the synovial membrane  production of effusion into the articular cavity 41 9-42