MSK Flashcards
clincial signs of fractures?
pain swelling crepitus deformity adjacent structural injury - vessels, nerves, ligaments, tendons
how to describe a fracture radiograph?
location - epi/dia/metaphysis fragments pattern - transverse, oblique, spiral displacement? angulated? valgus(distal away from midline)/varus?
general steps to fracture healing?
bleeding
inflammation - neutrophils/macrophages
new tissue - fibro/osteo/chondroblasts
remodelling - macrophages, osteoblasts and clasts
what happens in the inflammation step of fracture healing?
haematoma forms
cytokines released
granulation tissue and blood vessel formation
what happens in the repair step of fracture healing?
soft callous formation w type II collagen - cartilaginous
hard callous formation w type I collagen - bone
what happens in the remodelling step of fracture healing?
callus responds to activity, external forces, functional demands etc (Wolff’s law)
excess bone removed
two types of bone healing?
primary : intramembranous ossification - mesenchymal stem cells → osteoblasts (absolute stability)
secondary : endochondral ossification - MSC → chondral precursor → osteoblasts (relative stability) more callous
principles of fracture management?
reduce
hold
rehabilitate
reduction options?
closed - manipulation / traction
open - mini incision / full exposure
hold options?
closed - plaster / traction
fixation - intramedullary pins/nails | extra medullary plate/pins/screws | monoplanar/multiplanar
rehabilitation principles?
use - retrain & pain relief
move
strengthen
weight bear
general fracture complications?
fat embolus
DVT
infection
prolonged immobility - UTIs, sores
specific fracture complications?
neurovascular/tendon/ligament injury non/mal union local infection degenerative change reflexive sympathetic dystrophy (excess pain)
what can affect fracture healing?
movement blood supply infection immune function nutrition
causes of fracture NoF?
osteoporosis (old)
trauma (young)
bony landmark division of intra and extra capsular NoF fractures?
intratrochanteric line
in which NoF fracture is blood supply more likely to compromised?
intracapsular
management for an extracaspualr fracture?
fix with plate and dynamic hip screw
management for an intracaspualr fracture? replacement options?
undisplaced = less risk to blood supply → fix with screws displaced = risk of AVN → replace in older pts(≥55), fix in young
total hip replacement in independent pts
hemiarthroplasty if lower mobility/multiple comorbs
what nerve should be tested in shoulder dislocation?
axillary nerve
first line Ix for shoulder dislocation?
x ray prior to manipulation
shoulder dislocation management?
traction counter traction with gentle internal rotation
adequate pt relaxation - benzodiazepines
what is a hill-sachs defect?
deformity of humeral head secondary to shoulder dislocation when it collides with glenoid
management options for distal radius fracture?
minimal displacement - cast/splint
instability/child - MUA & K wire
displaced/intraatricular - open reduction internal fixation with plate and screws
management options for tibial plateau fracture?
non operative - true undisplaced w good joint line congruancy
operative - restore articular surface using plate and screws , ±bone graft/cement
management options for ankle fracture?
non-operative - below knee cast then physio (Weber A/stable B)
operative - ORIF ± syndemsosis repair (Weber unstable B/C)
how can ankle fractures be classified?
weber A - below syndesmosis, more stable
weber B - at level of syndesmosis
weber C - fibular fracture above syndesmosis
2 types of low back pain?
non-speciifc - no underlying cause found
mechanical - pain after abnormal stress/strain
causes of lower back pain?
mechanical - disc herniation/degenrartion, annular tear, oA tumours infection spondyloarthropy pars interarticularis injury visceral
what symptoms indicate sciatica?
unilateral leg pain ≥ back pain pain radiating to feet/toes paraesthesia straight leg raising test = more pain localised neurology
when is imaging indicated for back pain?
only if it’s likely to change the management (specialist care)
conservative treatment for back pain?
analgesia NSAIDs manipulation acupuncture massage
red flags for low back pain?
weight loss fever ≤19 yrs night pain = imaging
red flags for leg pain?
bowel/bladder dysfunction
saddle anasethisa
neurological deficit
=imaging
what back pain diseases require early diagnosis for effective treatment?
myeloma
metastases
inflammatory arthropathy
tuberculosis of spine
imaging for low back pain?
MRI - primary
radiographs, CT
different pain therapies?
waiitng physical therapy analgesia facet injections root blocks epidural injection - interlaminar, caudal, transforaminal neurostimulation
surgical options for back pain?
decomprreesison of nerve roots/spinal stenosis
disc replacement
fusion
what is the female athlete triad?
disordered etaing
amenhorrhea
osteoporosis
→ stress fractures
how does a stress fracture occur?
overuse → stress exerted on bone is greater than its capacity to remodel → bone weakens → stress fracture → ±complete fracture
causes of pathological fractures?
osteoporosis malognancy vit d deficiency → osteomalacia/rickets osteomyeltiis pages disease osteogensis imperfecta
causes of secondary osteoporosis?
hypogonadism
excess glucocorticoids
alcoholism
pathophysiology of OI?
decreased type 1 collagen (abnormal or decreased secretion) → insufficient osteoid production → brittle bones
stages of pages disease?
osteoclastic activity
mixed osteoclastic-blastic activity
osteoblastic activity
malignant denegernation
what malignancy is blastic?
prostate
what malignancies are lytic?
kidney
thyroid
lung
what malignancy is lytic and blastic?
breast
primary bone cancers?
osteosarcoma
chondrosarcoma
Ewing sarcoma
lymphoma
different types of tendinopathies?
tendinosis - abnormal thickening
tendinitis
rupture
how are ligament injuries classified?
grade I - slight incomplete tera
grade II - moderate/severe incompleet tear - some joint instability
garde III - complete tearing , obvious instability
treatment options for tendon/ligament tears?
immobilise - plaster/boot/brace
or
surgery - suture
disadvantages of immobilisation for injured ligaments?
less overall strength of repair
protein degradation ≥ synthesis → ↓ collagen
inferior tissue production by blast cells
resorption of bone at ligament insertion
↓ tissue tensile strength
benefits of mobilisation on injured ligaments?
scars are wider stronger and more elastic
better alignment and quality of collagen
outline intramembranous ossification?
eg cranial boens and clavicle
mesnchycmal cells condense → differentiate into osteoblasts → ossification centre forms → secreted osteoid traps osteoblasts → osteocytes → trabecular matrix and periosteum form → com[act bones develops → blood vessels condense into red bone marrow
different between primary and secondary ossification centres?
primary - site of pre-natal bone growth through endochondral ossifatcion at central part of bone
secondary - post natal bone growth at the physics
outline endochondral primary ossification?
mesenchymal differetiaiotn at primary centre → cartilage model of skeleton forms → capillaries penetrate , calcifatcion at primary centre (spongy bone), perichondrium into periosteum → cartilage and chondrocytes continue to grow at ends of bone → secondary centres form
outline endochindral secondary ossification?
long bone lengthening
happens at physis where theres cartilage
epiphyseal side → hyaline cartilage divides to form HC matrix
diaphysial side → cartilage calcifies and dies → replaced by bone
why are children bones more elastic than adults? what can this lead to?
↑ density of Haversian canals
plastic deformity - bends before breaking
buckle fractures - column like
greenstick fracture
4 differences between child and adult bones?
more elastic
physis present
↑ speed of heeling & remodelling
when does physis closure complete?
girls 15-16
boys 18-19
what is developmental dysplasia of the hip?
in neonates where head of femur is unstable or incongruous in relation to the acetabulum
dysplasia → sublaxation → dislocation
risk factors for developmental dysplasia of the hip?
female first born breech FH oligohydraminos swaddling of hip
how is developmental dysplasia of the hip usually picked up?
baby check
RoM check - limited hip abduction
investigations for developmental dysplasia of the hip?
US from birth to 4 months
post 4 months - xray
treatment options for developmental dysplasia of the hip/
reducible hip and <6months : Pavlik harness
failed harness or 6-18months : manipulation under anaesthesia + closed reduction and spica
clubfoot alt name?
congeniital talipes equinovarus
risk factors for clubfoot?
hawaiin
M2:1F
genetic PITX1 gene
what is the CAVE deformity in clubfoot?
due to muscle contraction Cavus - high arch, tight FHL, FDL Adductus of foot - tight tibialis post and ant Varus - tight tendoachilles and TP, TA Equinous - tight tendoachilles
treatment for clubfoot?
ponsetti method is gold standard series of casts to correct deformity operative treatment foot orthosis brace ± further Sx
what is achondroplasia?
autosomal dominant in FGFR3
inhibition of chondrocyte proliferation in proliferative zone of physis → defect in endochondral bone formation
what is thizomelic dwarfism?
humerus shorter than forearm
femur shorter than tibia
normal trunk
signs/symptoms of OI?
fragility fractures short stature scoliosis blue sclera soft brown teeth worming skull hypermetabolism
what is an avulsion fracture?
occurs where ligament/tendon attaches
how are phsyeal injuries classified?
Salter-Harris classification
1 - physical Separation
2 - fracture transverses physis and exits metaphysis (Above)
3 - fracture transverses physis and exits epiphysis (Lowe)
4 - fracture passes Through epiphysis, physis and metaphysic
5 - crush injury to physis
what can physis injuries lead to?
growth arrest
whole physis = limb length discrepancy
partial = angulation as unaffected side keeps growing
treatment for growth arrest?
limb length correction - shorten or lenghtne
angulation - stop growth of unaffected side or reform bone (osteotomy)
what’s most often used to restrict fractures in children?
splints and plaster
first thought for a limping child?
septic arthritis - emergency!
what can be used to score probability of septic arthritis?
Kocher's classification non-weight bearing ESR ≥ 40 WBC ≥ 12000 Temp ≤36 or ≥ 38
what is perthes disease?
idiopathic necrosis of the proximal femoral epiphysis
4-8 years old
M4 : 1F
4 cause of the limping child?
septic arthritis
transient synovitis
perthes disease
SUFE
what is transient synovitis?
inflamed joint in response to systemic illness
supportive treatment with abx
what is SUFE?
slipped upper femoral epiphysis - proximal epiphysis slips in relation to metaphysis
risk factors of SUFE?
obese adolescent males
12 -13 yrs with rapid growth
hypothyroidism/pituitarism
treatment for SUFE?
screw to prevent further slipping
outline the structure of a synocvila joint?
synovium - lining containing synoviocytes (A- phagocytic type , B - hyaluronic acid producing) and type I collagen
synovial fluid - hyaluronic acid rich
articular cartilage - type II collagen and preoteoglycan
what changes occur during inflammation?
↑ blood flow
leukocytes migrate into tissues and are activated/differentiate
cytokines produced - TNFa, IL6,1,17
pathogenesis of gout?
deposition of uric acid (monosodium urate) crystals in joints → inflammation
rf = hyperuricaemia (genetics, ↑ purine intake,, renal disease)
pathogenesis of pseudogout?
deposition of calcium pyrophosphate dihydrate → inflammation
rfs = background OA, elderly, intercurrent infections
symptoms of gout?
gouty arthiritis
tophi - subcutaneous crystals
podagra - MTP joint of big toe affected, ↑ pain, resolves spontaneously
how is gout seen on X-rays?
rate bite erosions on big toe MTPJ
investigations for gout?
joint aspiration for synovial fluid analysis
gout management?
acute - colchicine , nsaids, steroids
chronic - allopurinol
how do gout and pseudogout differ in synovial fluid analysis?
shape - needle vs brick
birefringence - negative vs positive
pathogenesis of RA?
abnormal synovial membrane
synovium → proliferated mass of tissue → pannus
due to neovascularisation , lymohangiogenesis , inflammatory cells
cytokine imbalance esp TNFa
role of TNFa in RA?
dominant pro-inflmamtory cytokine
causes pannus & synovitis
activates osetcolasts → bony erosions
destroys synoviovytes → jt inflammation → pain and swelling
activates chondrocytes → cartilage degradation → jt space narrowing
functions of TNFa?
releases proniflmmatory cytokines hepciidn induction PGE2 production chemokine release endocethelial cell activation → leukocyte accumulation angiogenesis chondrocyte activation → ↑ MMP, ↓ cartilage osteoclast activation
symptoms of RA?
polyarthrits - common in hands and wrists , MCP , PIP< MTP symmetricla early morning stiffness extensor tenosynovitis bursitis
extra articular manifestations of RA?
rheumatoid nodules, fever, weight loss
vasculititis
episcleritis
amyloidosis, lung daisies, felty’s syndrome
what can be detected in blood in RA patients?
rheumatoid factotr - IgM autoantibody against Fc portion of IgG
antibodies to citrullinated protein antigens
what is felty’s syndrome?
splenomegaly, leukopenia and RA
what are rheumatoid nodules?
central area of fibrinoid necrosis surrounded by histiocytes and connective tissue
what enzymes mediate citrullination of peptides?
peptidyl arginine deaminases
management of RA?
early recognition of symptoms and aggressive treatment
DMARDs
1st - methotrexate with hydroxychloroquine/sulfasalazine
2nd - biologics, janus kinase inhibitors
prednisolone but not long term
MDT approach
biologic options for RA?
anti-TNFa - infliximab, etanercept
anti-B cells - rituximab
abatacept
IL-6 inhibitors - tocilizumab
what is ankylosing spondylitis?
seronegative spondyloarthropy chronic sacroilitis spinal fusion young males HLA B27
symptoms of ankylosing spondylitis?
lower back pain/stifness in early morning, improves w exercise ↓ spinal movements peripheral; arthritis achilles tendonitis fatigue
what will blood tests show in ankylosing spondylitis?
normocytic anaemia
HLA B27
↑CRP,ESR
management for ankylosing spondylitis?
phhysio
nsaids
exercise
DMARDs
how does psoriatic arthritis present?
assymetrical , IPJs ±symmetrical involvement of small joints spinal and sacroiliac jt inflammation oligoarthritis of large jts arthritis mutilans - pencil in cup deformity
investigations for psoriatic arthritis?
xray
MRI - sacroilitis, enthesitis
bloods - seronegative
management of psoriatic arhtiritis?
DMARDs - methotrexate
what is reactive arthritis?
sterile inflammation of jts following infetcion , 1-4 weeks (esp urogenital and GI)
extra-articular manifestations of reactive arthritis?
enthesitis
skin inflammation
eye inflammation
what can reactive arthritis often be the first manifestation of?
HIV or Hep C
what autoantibodies are commonly involved with SLE?
antinuclear antibodies - high sensitivity but not specific (quite common in gen pop , needs to be in combo with clinical features)
anti-dsDNA antibodies - high specificity
anti-phospholipid antibodies
risk factors for SLE?
F9 : 1M
15-40yrs
african/asian ancestry
what are the seronegative spondyloarthopathies?
ankylosing spondilytis
reactive arthritis
psoriatic arthritis
entreropathic synovitis
what is commonly seen in connective tissue disorders?
arthralgia and arthritis
autoantibodies
Raynaud’s phenomenon
what is reynauds phenomenon?
intermittent vasopsams of digits on cold exposure → blanching → cyanosis → rectaove hyperaemia
whites → blue → red
clinical manifestations of SLE?
malar rash - spares nasolabial fold photosensitive rash mouth ulcers hair loss Raynaud's arthralgia ± arthritis serositis glomerulonephritis cerebral disease
what do anti-phospholipid antibodies increase the risk of?
arterial and venous thromboses
what will bloods show for SLE?
↑ ESR but normal CRP unless infection, arthritis or serositis haemolytic anameia, thrombocytopenia ANAs, anti-dsDNA, antiphospholipid low C3 & C4 ↓albumin ↑protein:creatine ratio
management of SLE?
hydroxychloroquine
±maintenance glucocorticoid
methotrexate/azathioprine
biologics
what is Sjorgen’s. syndrome?
autoimmune exocrinopathy
dry eyes, dry mouth and enlarged parotid gland
non-erosive arthritis and Raynaud’s phenomenon
rheumatology diagnostics?
bloods
synovial fluid analysis
x rays, US. CT , MRI
rheumatology blood tests?
FBC U&E LFT bone profile ESR CRP
what’s usually raised in FBC of septic arthritis?
WCC
what can be low in a FBC for inflammatory arthritis?
↓Hb
why are U&E done in rheumatology?
renal impairment eg in SLE, vasculitis, chronic inflammation and with NSAIDs
why are LFTs done in rheumatology?
DMARDs → liver damage
↓ albumin → ↓ synthesis in liver or leakage form kidneys
what will be raised in bone profile for Paget’s disease?
↑↑ALP
what is synocvial fluid analysis used to diagnose?
septic arthritis - gold standard , send for MC&S
crystal arthritis
3 differences between septic and reactive arthritis?
postive culture, give abx and joint lavage
4 X-ray features of OA?
loss of joint space
osteophytes
subchondral cysts
subchondral bony sclerosis
3 xray features of RA?
soft tissue swellling
peri-articular osteopenia
bony erosions
US changes in RA?
synovial hypertrphy
↑ blood flow
erosions
RA vs OA xray?
both jt space narrowing
OA : sclerosis and osetophytes
RA : osteopenia, bony erosions
