joints Flashcards
what are the 6 different types of joint (diarthrosis)
hinge, ball and socket, pivot, ellipsoidal, saddle, planar
whats an example of snap joint
horse elbow joint
what is a snap joint
some hinge joints that at a high energy state in an intermediate position
what is a synostosis
bone
synchondrosis
cartillage
symphysis
fibrocartillage
syndesmosis
fibrous
gomphosis
fibrous
amphialthrosis
outdated term used for intervertebral joints which include one symphysis and two diarthroses
what are diarthrosis
more mobile synovial joints with fluid and cartilage which can be subclassified by movement
hinge
hock of equine or canine elbow
pivot
cat radioulnar 1 axis
saddle
interphalangeal 2axes
ellipsoidal
antebrachiocarpal joint 2 axes
ball and socket joint
hip, 3 axes
planar
intercarpals/intertarsals
what are the structure of the diarthrosis
synovial membrane is weak and floppy vs fibrous capsule which is thick and tough
outline synovial membrane
glistening pink, many vessels and nerves, often incomplete, no basement membrane, synoviocytes type A (phagocytic) and type B (secretory) folded or tufted, often large pouches to allow movement
outline synovial fluid
secreted by membrane, plasma ultrafiltrate and hyaluronate (long chain glycosaminoglycan), lubricative and nutritive
what is the gross structure of articular cartilage
varies in fibrous content, 1mm in the dog, no vessels or nerves fed by diffusion
what has the most articular cartilage
1 fluid 2 capsule 3 bone
what are tangential fibres
arcade arrangement of collagen that are smooth and firmly anchored, perpendicular deeper
describe the matrix mesh of articular cartilage
type 2 collagen resists tension, there is a hyaluronate mesh made of glycosaminoglycan, and proteoglycans which have a protein core and GAG side chains
what is the function of the proteoglycans
retain water, resist compression, seep fluid into joint space
microstructure of proteoglycans
protein core made of aggrecan, chondroitin sulfate gag, keratin sulfate gag and a linker protein.
role of gags having a negative charge
1 repeal each other and attract water, 2 resist compression and weeps in/out of joint space, 3 lubricates joint and pumps nutrients/gases
articular cartilage conditions
degeneration of collagen/hyaluronate/peptidoglycan meshes reduce joint function.
how to treat articular cartilage conditions
supplement with chrondroitin and /or glucosamine (precursor of sugars in GAGs)
what does enrofloxacin cause
abnormal development of articular cartilage
what are capsule ligaments
fibrous capsule attaches to periosteum and is continuous with articular cartilage, supports joint and has much innervation
what are discs
fibrocartilage ingrowths from capsule, if split into two parts they cause a disc (complete) e.g. jaw joints
what are mensici
fibrocartilage ingrowths from capsule, incomplete e.g. in stifle, they allocate diff movements to diff compartments
what is a labrum
fibrocartilaginous extension to joint surface e.g. hipsocket
what is a fat pad
they lie between synovial membrane and capsule
what is a bursae
small synovial spaces between bones and something else e.g. tendon or occasional muscles/ligaments or skin
