Chapter 9 Joints Flashcards
Joint (articulation)
Any point where two bones meet
Arthrology
Science of joint structure, function and dysfunction
Kinesiology
The study of musculoskeletal movement
Bony joint
An immobile joint formed when the gap between two bones ossifies, and the bones become a single bone
Bony joint examples
-left and right mandibular bones in infants
-cranial sutures in elderly
-attachment of first rib sternum with old age
Fibrous joint
Adjacent bones bound by collagen fibers that emerge from one bone and penetrate into the other
3 types of fibrous joints
-sutures
-gomphoses
-sydnesmoses
Sutures
Immobile or slightly mobile fibrous joints in which shirt collagen fibers bind the bones of the skull to each other
Serrate suture
Interlocking wavy lines
-coronal, sagittal, lambdoid sutures
Lap (squamous) sutures
Overlapping beveled edges
-temporal and parietal bones
Plane (butt) suture
Straight non-overlapping edges
-palatine processes of the maxillae
Gomphoses
Fibrous joint
Attachment of a tooth to its socket
-collagen fibers attached tooth to jaw bone
-allows tooth to move a little under the stress of chewing
Syndesmosis
Fibrous joint at which two bones are bound by long collagen fibers
-mobile ex) membrane joining radius to ulna
-non mobile ex) joint between tibia and fibula
Cartilaginous joint or amphiarthrosis
Two bones linked by cartilage
Two types of cartilaginous joints
Synchondroses
Symphyses
Synchondrosis
Bones joined together by hyaline cartilage
Ex) temporary joints in Epiphyseal plates in children, first fib attachment to sternum
Symphyses
Two bones joined by fibrocartilage
Ex) pubic symphysis joins right and left pubic bones with interpubic disk
Synovial joint or diarthrosis
Joint in which two bones are separated by a joint cavity
Articular cartilage
Layer of hyaline cartilage that covers the facing surfaces of two bones
-unusually 2-3mm thick
Joint cavity
Separates Articular surfaces
Synovial fluid
Slippery lubricant in joint cavity
-feels like raw egg whites
-nourishes Articular cartilage and removes waste
-makes movement of synovial joint almost friction free
Joint capsule
Connective tissue that encloses the cavity and retains fluid
Outer fibrous capsule
Continuous with periosteum of adjoining bones
Inner cellular synovial membrane
Composed mainly of fibroblast like cells that secrete synovial fluid and macrophages that remove debris from the joint cavity
What does a Articular disc form?
Forms a pad between articulating bones that crosses the entire joint capsule
Ex) temporomandibular joint
Meniscus
Moon shaped cartilage in knee
-in each knee menisci extend inwards from the left and right
What do synovial joints that contains fibrocartilage growing inwards from joint capsule do?
-absorb shock and pressure
-guide bones across each other and improve their fit together
-stabilize joints
Tendon
Strip of collagenous tissue attaching muscle to bone
Ligament
Strip of collagenous tissue attaching one bone to another
Bursa
Fibrous sac filled with synovial fluid
-located between muscles, where tendons pass over bone or between bone and skin
^cushions muscles, helps tendons slide more easily over joints
Tendon sheath
Elongated cylindrical bursa wrapped around a tendon
-in hand and foot
What does exercise do for joints?
-Exercise warms synovial fluid
-squeezes fluid and metabolic waste out of cartilage
-synovial fluid is more likely to be absorbed by cartilage taking in oxygen and nutrients
Range of motion (ROM)
The degrees through which a joint can move
Ball and socket joints
-smooth, hemispherical, head fits within cup like socket
-only multiracial joints
Ex) shoulder, hip
Condylar joints
-oval convex surface of one bone fits into a complementary shaped depression on the other
-biaxial joints
Ex) radiocarpal, metacarpophalangeal joints
Saddle joints
-both bones have an articular surface that is shaped like a saddle
-biaxial joints
Ex) sternoclavicular joint
Pivot joints
-a bone spins on its longitudinal axis
-monoaxial joints
Ex) atlantoaxial joint (C1+C2), radio ulnar joint at the elbow
Plane joints
-flat articular surfaces, bones slide over each other
-usually biaxial
Ex) between carpal bones of wrist, between tarsal bones of ankle
Hinge joints
-one bone with convex surface fits into a concave depression of another bone
-monoaxial joints
Ex) elbow, knee, toes, joints within fingers
Tibiofemoral
Knee joint
Patellofemoral
Gliding joint
How is the knee stabilized?
-quadriceps tendon in front
-tendon of semimembranous muscle on rear on thigh
-lateral meniscus and medial meniscus
How many bursae’s are in the knee joint
At least 13
Temporomandibular joint syndrome
-clicking in jaw
-pain from jaw to neck to shoulders and back
-can cause headaches, vertigo, ringing in ear
Caused by: misalignment of teeth
Treatment: aligning teeth, drugs, physical therapy
Sprain
Forcible twisting of joint, stretches or tears its ligaments
Strain
Stretched or partially torn muscle
Less serious then sprain
Dislocation
Displacement of bone from joint resulting tearing of ligaments, tendons, and articular capsules
Subluxation
Incomplete dislocation
Bursitis
Inflammation of bursa
Bunion
Bursitis+ ossification on toe
Adhesions
Fibrous bands between bone surfaces
Spurs
Excess bone tissue along joint edges
Arthritis
Pain and inflammation or joints
Osteoarthritis
Most common form of arthritis
-results from years of joint wear
- articular cartilage softens and degenerates
-cracking sounds (crepitus)
Rheumatoid arthritis
Autoimmune attack against joint tissues
-misguided anti bodies attack synovial membrane,
-joint ossifies
Ankylosis
Solidly fused immobilized joint
Arthroplasty
Replacement of diseased joint with artificial device prosthesis
Gout
-excessive build up of uric acid in the blood
-can be temperature dependent
