week 1 Flashcards
Classify joints according to the 3 main classes of joint: fibrous, cartilaginous, synovial
fibrous joint- immobile - skull sutures
cartilaginous joint- slightly mobile- e.g intervertrebral disks
synovial (diarthrosis)- freely mobile.
Relate the structural elements of different joint to their functions (including intra- and extra-articular elements)
congruity
fibrous capsule (+ its thickenings/ ligaments)
intraarticular ligt (ACL,PCL)
Packing- inside joints e.g fat pads menisci
muscles
Explain how the components of cartilage contribute to its function
large ptoteoglycan- glycosamino glycan (GAG) lots of core protein side chains.- can form large polymetric structure.
-ve charged so draws water inside it.
chondrocite only cell inside cartilage.
have type 2 collagen fibrils woven though the aggrecans- creates framework holding sugar molecules together. similar orientation initially but as deeper into collagen- becomes more angled.
Describe the composition, process of formation and role of synovial fluid, and relate this to the pathophysiology of synovial effusion
synovial lining- allows nutrients through. + drainage into lymph.
superficial fenestration capillaries- close to synovial surface- needs to supply all cartilage and joint space.
usually only about 10-100 ml of fluid- but can increase
in inflammation- inflam mediators stay in the fluid, lower HA concentration.
Outline the developmental origin of the somites and their contribution to the musculoskeletal system.
proliferation presomitic mesoderm. (think like making sausages) form 44 somties, one every 5 hours during formation.
head
sclerotome- bone and cartilage.
myotome- muscles
dematome- dermis
Recognise the molecular signals that pattern the developing musculoskeletal system.
clock and waveform model
fgf - proximal/ distal
sonic hedgehog - A/P axis
wnt - dorsal ventrally axis
Relate the adult dermatome to its embryonic origin in the somites.
dermatome has two meanings- area of skin supplied by one spinal nerve and
subdivsions of the developing somite- gives rise to the dermis and connective tissue.
Oultine limb formation in the embryo with respect to muscle differentiation and innervation.
Recognise pathologies of musculoskeletal development.
spina bifida- incomplete arch fusion in vertebre
amelia- loss of a limb
mermomelia- partial loss of a limb.
dwarfism- inability to convert cartiladge to bone
Describe patterns of joint disease using appropriate terminology (e.g. monoarthritis, oligoarthritis, polyarthritis) and identify common causes for these patterns
mono- 1
oligo - 2 to 4
poly - more than 4
Identify important features of the rheumatological history and differentiate between an inflammatory and non-inflammatory arthritis in relation to the history and examination
Outline the pathogenesis of rheumatoid arthritis and relate to the clinical presentation of rheumatoid arthritis
HLA-DRB1 most prevalent susceptibility gene
dendritic gene activation- exposed to ‘self’ gene. present to T Cell- activate B cells e.t.c.
travel to synovium- cascade and produce enzymes which degrades cartilage.
Compare rheumatoid arthritis with other common inflammatory joint diseases such as gout and psoriatic arthritis
rheumatoid nodules- associated with +ve rheumatoid factor.
RF is an Igm attaching to an IgG
Discuss pathological changes in cartilage and the chondrocyte which lead to cartilage degradation
early fibrillation and chondrocyte loss
- deep fissures form with poor staining
main cleavage enzyme- aggricanse - over time MMP more.
aggricanase can be reversed
Outline the pathogenesis of osteoarthritis and relate this to the clinical presentation of osteoarthritis
Discuss the conservative, medical and surgical treatments of osteoarthritis
intra articular roids
painkillers
uni/tkr
