Ortho Flashcards
Teen, dull ache on lower femur, XR shows “sunburst” pattern of subperiosteal bone?
Osteosarcoma
Compartment syndrome?
- if not complaining of pain, what should raise suspicion?
- why does presence of pulse not rule it out?
- does XR show any pathology?
- how long until muscle death?
- why might aggressive IV fluids be needed?
- what medications NOT to give as it makes it worse?
- excessive use of breakthrough painkillers (plus pallor, paraesthesia, loss of pulse, paralysis)
- pulse may still be felt as microvasculature compromise leads to muscle necrosis which can be compressed allowing pulse through
- no
- 4-6 hours
- In case of myoglobinaemia causing acute tubular necrosis
- DO NOT give anticoagulation, it makes it worse
Scaphoid fracture:
- signs? (5)
- Ix?
- initial management?
- orthopaedic management?
- what is the vascular compromise?
- Maximal tenderness over anatomical snuffbox
- Wrist joint effusion (not if <4 hrs or >4 days old)
- Pain in telescoping of thumb
- Tenderness of scaphoid tubercle (volar wrist)
- Pain on ulnar deviation of wrist
- XR: AP, lateral, oblique and Zilter view (ulnar deviation of wrist)
- MRI should be 1st line imaging but usually 2nd line after XR
- CT more sensitive than XR and may be used also if MRI not available
- Futuro splint or elbow backslab
- Referral to ortho for review and new imaging in 7-10 days
Undisplaced # of waist: cast for 6-8 weeks
All others: surgical fixation
(esp proximal pole, high risk of AVN)
Dorsal carpal arch of radial artery
Causes of gout?
XR features?
DARRT:
Diuretics Alcohol Renal disease Red meat Trauma
XR:
- ‘punched out’ lesions with sclerotic margins
- preservation of joint space (until late disease)
- Soft tissue tophi may be seen
- joint effusion
RF for AVF?
Imaging?
Long term steroids
Chemo
Alcohol abuse
Trauma
XR:
Early - may be normal or show osteopenia or micro fractures
Later - head collapse may show crescent sign
IX of choice - MRI
How to tell if hip pain in an adult is referred from lumbar spine?
Positive femoral nerve stretch test
Lie pt prone, extend hip with straight leg, then bend knee - elicits pain if referred from lumbar spine
Management of suspected osteoporosis in a patient with a suspected fragility fracture?
Age 75+ - start on oral bisphosphonate
<75 - perform a dexa scan, then enter the result into a FRAX calculator to determine risk
Imaging for spinal trauma?
XR first line if no neuro symptoms
CT if abnormal XR or if neuro signs present
Immediate management of open fracture?
IV Co-amoxiclav
Lavage and debridement within 6 hours in theatre
External fixation preferred due to infection risk - wait for soft tissue swelling to reduce before definitive management
Enchondroma?
Intramedullary metaphyseal cartilaginous tumour caused by failure of normal enchondral ossification at growth plate
Lucent with patchy sclerosis, risk pathological frac, asymptomatic
Osteoid osteoma
nidus of immature bone with sclerotic halo, intense pain esp at night, greatly relieved by NSAIDs
Simple vs aneurysmal bone cyst?
Simple:
Growth defect, asymptomatic, incidental finding, risk pathological frac
Aneurysmal:
AVM, locally aggressive, cortical expension and destruction (painful)
Curettage and bone graft
Osteosarcoma
Kids, usually around knee, peirosteal elevation and sunburst sign, assoc with retinoblastoma
Teenager with warm, boney swelling, fever and raised CRP - what tumour?
Ewing’s sarcoma
2nd most common, worse prognosis
Brodie’s abscess?
subacute osteomyelitis
Thin rim of sclerotic bone surrounding abscess
Brown’s tumour?
AKA osteitis fibrosis cystica/osteoclastoma
Due to untreated hyperparathyroidism
Histologically exactly same as Giant Cell tumour
Giant cell tumour
Multinucleated giant cells within a fibrous stroma
20-40 y/o, epiphysis of long bones
soap bubble/souble bubble appearance
Paget’s disease?
Uncontrolled osteoclast activity - increased bone turnover
Bone pain (skull, spine, pelvis, femur) Isolated raised ALP
Deafness, fractures, skull thickening, high output cardiac failure
XR/isotope bone scan
Rx: bisphosphonates
Osteomyelitis pathophysiology?
Causative organisms?
Leucocyte enzymes -> local osteolysis/pus -> impaired blood flow -> difficult eradication -> sequestrum (dead bone) -> involucrum (new bone around)
Staph aureus most common
Salmonella in sickle cell
Ix: MRI
6 weeks fluclox/clinda
May need surgery and washout if not treating/if chronic (in chronic abx suppresses bacteria but not eradicate)
When each of the following cause septic arthritis:
- staph aureus?
- strep?
- h influenzae?
- neis gon?
- e coli?
Staph - most common
Strep - second commonest
H influenzae - was commonest in kids before vaccine
Gon - consider in young adults
E coli - elderly, IVDU, seriously ill
Ix septic arthritis?
Rx?
Joint aspirate BEFORE Rx
Fluclox/clinda 6 weeks +/- arthoroscopic lavage
Osteoporosis:
- what is it?
- common causes?
- what fractures are common?
quantitative defect of bone - low mineral density
Alcohol, steroids, smoking, menopause/low oestrogen, malabsorption, CKD, certain drugs, hyperthyroidism
NOF, vertebral crush, colles
Who should have osteoporosis risk assessed?
What scores are used?
When to reassess?
All women 65+ and men 75+
AND those younger but with risks e.g. steroid use, previous fragility fracture, low BMI
FRAX or QFracture - assess 10 year risk of fragility fracture
FRAX without DEXA gives low, med and high risk scores
With gives no rx, consider rx and recommend rx
Do not reassess again before 2 years unless significant change to circumstances
What to do if someone has a suspected fragility fracture?
If <75 - organise DEXA and put score into FRAX tool
If 75+ - treat regardless
Osteoporosis prevention in long-term steroids?
Just 7.5mg Pred for 3 months massively increases risk
If 65+ OR have previously had fragility fracture - treat
If <65 - DEXA
(if DEXA between 0 and -1.5, repeat scan in 1-3 years)
Ix of suspected spinal fragility fracture?
XR - may show wedge
2nd line - CT (shows bones) or MRI (shows if pathological frac e.g. from cancer)
If fracture organise DEXA
Management osteoporosis?
Calcium and Vit D
Alendronate 1st line Zolendronic acid once yearly IV Strontium (increased osteoblasts) Raloxifene (SERM) Denusomab (monoclonal AB against RANK ligand reducing osteoclast activity)
SE bisphosphonates?
Oesophagitis/ulcers
Osteonecrosis of jaw
Atypical stress fractures (esp prox femoral shaft)
Acute phase response may follow administration (fever, myalgia)
Hypocalcaemia (reduced efflux from bone, usually subclinical)
Osteomalacia?
Causes?
Qualitative defect - abnormal softening. Defective mineralisation of osteoid (immature bone) due to inadequate calcium/vitD
(Rickets in kids)
VitD deficiency
CKD
Drugs e.g. anticonvulsants
Liver disease
Bone pain, bone/muscle tenderness, fractures (esp NOF), proximal myopathy (waddling gait)
Bloods:
- low vitD, Ca, Phos
- Raised ALP, PTH
XR: translucent bands (Looser’s zones, or pseudofractures)
Rx: VitD supplementation, Ca supplementation, possibly phosphate supplementation
What is renal dystrophy?
Bone changes due to CKD. Reduced phosphate excretion and VitD activation -> secondary hyperparathyroidism, sclerosis of bone, calcification of soft tissues
Mechanical back pain?
Recurrent, relapsing, reciting pain with NO neurological symptoms, worse with movement, relieved by rest
Obesity, inactivity, poor lifting technique, facet joint OA, spondylosis (water loss from disks causing secondary OA)
NSAIDs, continue normal activity, physio
DO NOT offer spinal XR for low back pain without trauma
MRI for back pain?
Only id it is likely to change management and where malignancy, infection, fracture, caudal equine or ank spond is suspected
57 y/o man sudden onset severe lumbar back pain when lifting lawn mower out of shed, worse on coughing?
Acute disc tear
Tear in annulus fibrosis which is richly innervated, MRI if suspect herniation, resolves in 2-3 months with analgesia/physio
