Joints General Notes PDF

Articulations (Joints) 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 or forms a joint. *There are total of496 joints total of 372 majority A moveable joints in human body. - is moveable * * * * * * * ibs...

Articulations (Joints) 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 or forms a joint. *There are total of496 joints total of 372 majority A moveable joints in human body. - is moveable * * * * * * * ibs and pine 93 Total , 7 oveable pper limbs 4 Total moveable ands wrists 4 Total moveable ower limbs 2 Total moveable oots an les Total moveable arynx 4 Total moveable ull 9 Total , oveable ⃰ Connect 2 bones. Hold the skeletal bones together ⃰ Allow the skeleton some flexibility so gross movement can occur ⃰ Make bone growth possible Classified by structure or function Movement 1. Immovable 2. Slightly Movable 3. Freely Movable Tissue (more common) 1. Fibrous 2. Cartilaginous 3. Synovial Joint classification Classification by structure Classification by function 1. Fibrous joints - bones held together by fibrous connective tissue 2. Cartilagenous joints - bones held together by cartilage range of 3. Synovial joints - complex structure with cartilage and cavities F 1. Synarthroses Immovable joints 2. Amphiarthrose Slightly movable joints 3. Diarthroses Freely movable joints a mobilities yn to ether with mphi two or both sided i twice, double General background 1 extra joint category! Bony joint (synostosis) Immobile (immovable) Fond when 2 bones ossify together (essentially merge or immobility resulting during weld together) joining when the tissue between the bones a re replaced by bone tissue - fuse in two pieces together together ossification Some cranial sutures (fissures in the cranium) become ossified resulting When the growth plate fuses/calcifies over (joining the epiphysis and diaphysis in long bones) in a solidsimmerable connection betweens the bones of the skull Fibrous joint (synarthrosis) 1. Suture dense connective skull tissue 2. Gomphosis 3. Syndesmosis *Bolt together *resembling tendon or ligament, a band 1. Sutures Suture: immobile joints in the skull (the fissures you see) through the thickness of the outer compact bone -“serrate” = wavy lines (like a serrated knife) - - - skull: parieta/frontal bones - “lap”/ “squamous” = diagonal line - - - Skull: temporal/parietal bones - “plane” / “butt” = straight line - - Paired maxillary and palatine bones - 2. Gomphosis found only in mouth where teeth attach to bone Tooth is “held in place” by fibrous periodontal ligament” made of collagen that originates from the jaw bone Fibrous “joint” permits slight movement when biting An important sensory mechanism that lets you know how hard or soft you are biting - - - - - 3. Syndesmosis Collagen fibers bind 2 bones More mobility than suture or gomphosis, but still very limited Tibia – fibula at distal end Radius – ulna at distal ends - - - Tibia/fibula Radius/ulna Note how far apart the radius/ulna are from one another compared to the tibia/fibula. This is one reason why your forearm is more “mobile” or flexible than your lower leg. Cartilaginous joints: (amphiarthrosis) ynchondroses when bone is bound joined by hyaline cartila e - The rowth plate in lon bones The first rib attaches to the sternum manubrium the first rib ymphyses where bones are joined by fibrous cartila e stock fibrocartilage ubic bone pelvis etween vertebrae absorbers *The sternocostal joints, also known as sternochondral joints or costosternal articulations, are synovial plane joints of the costal cartilages of the true ribs with the sternum. *The only exception is the first rib, which has a synchondrosis joint since the cartilage is directly united with the sternum. *The sternocostal joints are important for thoracic wall mobility. The long bone in a child is divided into four regions the diaphysis shaft or primary ossification centre , metaphysis where the bone flares , physis or growth plate and the epiphysis secondary ossification centre. n the adult, only the metaphysis and diaphysis are present. Synovial joints - ery complex - synovial joint because the joints are separated by a space synovial cavity , where synovial fluid is retained - ynovial fluid rich in albumin blood protein and hyaluronic acid a lubricant a Synal Synovial joints stability and mobility a re rise verso - Joint membrane: - Outer fibrous capsule (continuous with the periosteum) - Inner synovial membrane àsecretes the synovial fluid into the joint capsule - Each bone involved in the joint is covered by articular cartilage » 2 mm thick -The bones making up the joint are “held together” by ligaments Help to locate the bones in the correct “place” so that their articular cartilage “rides” correctly Types of joints: classification by shape Ball & Socket joints (hip and shoulder) Hinge joints (ulna and humerus… knee, fingers and toes) Pivot joints (radius and ulna…forearm/ elbow and the first 2 vertebrae of your spine) Saddle joints (thumb, sternum/clavicle) Condyloid joints (fingers) Types of joints: classification by shape shallower socket which gives Ball & Socket joints (hip and shoulder) has a a ter grea tion but - Wo instability. The ONLY multi-directional joints you have flexion extension abduction - - adduction rotation - - - circumduction range of gives away some Types of joints: classification by shape Hinge joints (ulna and humerus knee, fingers and toes) 1 range of movement (ie. flip-phone) dows flexion and extension Types of joints: classification by shape Pivot joints (radius and ulna… forearm/elbow and the first 2 vertebrae of your spine) radius promation cause - if since ulna can't twist because of hinge joint supination When 1 bone spins on another, when you say no, or turn a door knob) Types of joints: classification by shape Saddle joints (thumb, sternum/clavicle) both bones have a concave and c o nve r structure 2 ranges of motion (hold something tight = sagittal plane, spread hand = frontal plane) very slightly rotate Condyloid joints (fingers) wrist 2 ranges of motion: make a fist = sagittal plane, spread fingers = frontal plane flexion-extension abduction adduction circumduction - - - Types of joints: classification by shape Gliding joints twofatsurfaces cangideorrotee & Bone surface almost flat Bones slide along each other Ex: carpal bone, patella-femur foot Complex joints Many joints have characteristics of multiple joint types Elbow is both a hinge joint (where ulna and humerus meet), as well as a pivot joint (where radius and ulna meet) Knee is similar to the elbow joint, without as much flexibility (much stronger and limited) Temporo-mandibular joint has both lateral and dorsal/ventral movement Complex synovial joints In a few joints, there is an articular disc. (jaw = temporo-mandibular), (sternum/collarbone =sterno-clavicular), (ankle = distal tibia-fibula) In your knee, this is called a meniscus for guidance of the knee bones for shock absorption Accessories to synovial joints mobility and stability a re wise versa Other structures present in synovial joints: Tendons: collagen-based connective tissue that hold muscle to bone dinamic Ligaments: collagen-based connective tissue that hold bone to bone they are statio Bursa: fibrous “sac” that holds synovial fluid static Wraps around muscles à prevent rubbing “bursitis” = inflammation of the bursa pain limited movement “tendon sheath” fibrous suc filled with synovial fluid-rduce and a friction between muscles , tendons and bones. Bursa if rise damage ve rs a capsule damages and Movements of various joints Your shoulder (ball and socket) is a good example of a joint that is “multiarticulate” The ball and socket allows for: Abduction of the arm (flap your arms like a bird, jumping jacks) Flexion of the arm (extending to shake a hand or open a door) Rotation of the arm (sweeping your desk) Movements of various joints Abduction = raising arms above head (moving away from the anatomical position in the FRONTAL PLANE) Adduction = returning arms to side (returning to anatomical position in the FRONTAL PLANE) The terms abduction and adduction refer to the ACTION, NOT THE APPENDAGE that you are moving (you can also abduct and adduct your legs at the hip joint). Movements of various joints Elevation = lifting body part in the FRONTAL PLANE (moving away from the anatomical position) In this case, the model is raising their shoulders in the frontal or coronal plane Depression = returning to anatomical position from elevation These terms refer to movement FROM the anatomical position, as well as back TO the anatomical position. These movement terms also refer to the PLANE of movement. In this case, we are dealing with the FRONTAL or CORONAL plane. Movements of various joints Protraction = moving body part forward (anterior movement) in a transverse or horizontal direction Retraction = posterior movement (“pushing out” his chest…he’s really pulling back his shoulders”) With these terms, there is reference to direction and plane of movement, however, this DOES NOT refer to the movement FROM or TO the anatomical position. Movements of various joints Flexion = decreasing joint angle In this case, the models elbow is in flexion Extension = increasing joint angle to “zero position” (where it would “naturally rest) Hyperextension = moving beyond the zero position Note that this movement DOES NOT refer to the plane of a joint, is only refers to the ANGLE of the joint. Movements of various joints Hyperextension = moving beyond the zero position Movements of various joints Circumduction = 1 end of the joint remains stationary, the other end makes a CIRCLE. Rotation = turning a joint longitudinally on 1 bone of the joint Movements of various joints Supination =ONLY for FOREARM, when you turn your forearm so that the palms face forward or ventral (anatomical position) Pronation = ONLY for the forearm, when you turn your forearm so that the palm faces posterior or dorsal Movements of hand joints Radial flexion = tilting the hand towards the thumb (towards the radius) Ulnar flexion = tilting hand towards the pinky finger (towards the ulna) In terms of your fingers: Flexion = curling fingers (like a fist) Extension = pointing your fingers Abduction of the FINGERS is when you spread your fingers apart Movements of hand joints Your THUMB is turned 90° from the rest of your fingers, so the previous “terms” for finger movement are DIFFERENT for your thumb Abduction = bring your thumb to your index finger (the “OK” sign) In terms of your THUMB: Flexion = bending towards the palm of your hand Extension = pointing thumb up (hitch-hiking) Hyperextension = when you make a 90° angle between your thumb and index finger (straight up hitch hiker thumb) Opposition = touch pinky with thumb Reposition = return to “zero” from the opposition position Movements of foot/ankle joints In terms of ANKLE movements Dorsiflection = lift toes up (standing on your heels) Zero position = feet flat on the ground, standing up In terms of your FEET: Your ankle can “roll” just like your wrist can “wave” Inversion = turning the plantar surface towards the median (standing on the outside of your feet) Eversion = turning the plantar surface laterally (standing on the arches of your feet) Plantar flexion = pointing toes down (standing on your toes) Complex joint: humero-scapular joint (shoulder) The scapula is connected to the thorax only by the clavicle (collar bone) Connection at the acromion process (look for a sharp hook) The joint between the clavicle and acromion = acromial-clavicular joint Humero-scapular joint Posterior view Anterior view ote how the ligaments and tendons wrap around the joint to hold the head of the humerus into the glenoid cavity. lso note how shallow the socket on the scapula is an effort to increase mobility of this joint. Complex joint: Elbow joint Actually 2 joints in 1 area Humero-ulnar joint Humero-radial joint Both enclosed by 1 single synovial joint capsule 3rd joint in the elbow: radio-ulnar joint head of the radius - radial notch in the ulna important because it permits the forearm rotation (supine/prone) rotation Your tibia/fibula (shins) cannot rotate as well Features of the hand and wrist Also remember that your hand and wrist comprise a number of different joint types: saddle, gliding and condyloid. Together, these joints give your hands and fingers a great deal of and mobility Costovertebral joints makingconnection it is Hip joint: Coxal bone - femur Knee and hip replacements Rheumatoid arthritis - An autoimmune disease Osteoarthritis - Bone degeneration due to old age Osteoarthritis of the spinal cord Bursitis Accumulation of synovial fluid in the bursa – due to chronic or acute irritation An extreme case! Sprain and Strain Sprain: ligament tear Strain: Tendon or muscle tear