MSK (LL) Vascular, Infections, Trauma, Toxins Flashcards
State the common vascular conditions of the lower limb
- avascular necrosis of head of femur
- arterial thromboembolism
- claudication of leg
- DVT
- varicose veins
State the vessels involved in blood supply to the head of femur
adults - trochanteric anastomosis (medial and lateral circumflex A, inferior gluteal A, superior gluteal A)
children - obturator A (found in ligamentum teres)
State the common cause of avascular necrosis of head of femur.
State the pathogenesis behind it.
fracture of neck of femur
fracture –> torn reticular A of medial circumflex A –> branch of obturator A not enough to supply head of femur –> avascular necrosis of head of femur
Avascular necrosis is prevalent in what demographic?
- elderly
- postmenopausal (atrophy of female reproductive organs –> decreased oestrogen –> higher risk of osteoporosis)
- osteoporic patients
State the main difference between trochanteric fracture of femur and fracutre of neck of femur
- trochanteric fracture of femur does not need replacement while fracture of neck of femur requires surgical replacement of head of femur
- trochanteric fracture of femur does not result in avascular necrosis of femur while fracture of head of femur does
Name the condition associated with this x-ray.
State a feature of the x-ray.
Avascular necrosis of head of femur
- Head of femur is flatter and disintegrated due to destruction of bone
State everything associated with asvascular necrosis of head of femur
AVASCULAR NECROSIS OF HEAD OF FEMUR
- common in eldelrly, post-menopausal women, osteoporotic patients
- commonly due to fracture of neck of femur from trauma
- retinacular A torn –> obturator A insufficient to supply head of femur
- requires hip replacement
Recall virchow’s triad
- hypercoaguability
- endothelial damage
- stasis of flow
State the pathogenesis of arterial thromboembolism
ARTERIAL THROMBOEMBOLISM
- thromboemboli from AF deposits in arteries in LL
State the common clinical presentation, complications and treatment for ARTERIAL THROMBOEMBOLISM
ARTERIAL THROMBOEMBOLISM
(1) Clinical presentation
- severe pain and coldness of affected limb
- certain pulses not palpable (dorsalis pedis, posterior tibial)
(2) Complication
- ischaemia and infarction of LL
(3) Treatment
- thrombolytics (tPA) and antiplatelert (clopidogrel)
State the cause and pathogenesis of claudication of leg
CLAUDICATION OF LEG
Cause = atheroscelerosis –> hyperlipidemia prediposes vascular wall to formation of lipid plaques
Pathogenesis
- narrowing of arteries cause supply-demand mistmatch in the muscles of the leg
- build up of lactic acid from anaerobic respiration causes pain in affected muscles
State the clinical presentations and treatment for claudication of leg
**CLAUDICATION OF LEG **
Presentation
- bilateral or unilateral presentation
- diminished pulses
- pain begins with use of leg (causes demand ischaemia and lactic acid build up) and gets bettter with rest
Treatment
- pentoxyfylline
- antiplatelets (clopidogrel)
- antihypertensives (ace-i = captopril, arb = candesartan)
- antilipids (hmg-coa reducatase-i = atorvastatin)
State everything you know about claudication of leg
(cause, pathogensis, presentation, treatment)
CLAUDICATION OF LEG
Cause = atherosclerosis (hyperlipidemia predisposes vascular walls to formation of lipid plaques)
Pathogenesis
- narrowing of arteries cause supply-demand mismatch in the muscles of the leg (demand ischaemia)
- build up of lactic acid from anaeruobic respiration causes pain in affected muscles
Presentation
- bilateral or unilateral
- diminished pulses
- pain on activity, better with rest
Treatment
- antihypertensives (captopril and candesartan)
- antilipids (atorvastatin)
- antiplatelets (clopidogrel)
- pentoxyfylline
State the cause of deep vein thrombosis
VENOUS stasis when sitting for long periods of time
State the clinical presentation, complications and treatment of deep vein thrombosis
DEEP VEIN THROMBOSIS
Presentation
- pain, warmth, red discolouration of elg
- swelling of leg (compresses nerves –> weakness and numbness)
Complication
- thrombus travels to lung –> pulmonary embolism –> death
Treatment
- rivaroxaban, apixaban monotherapy
- LMWH + warfarin OR LMWH + dabigatran/rivaroxaban/edoxaban
State everything you know about deep vein thrombosis
(cause, clinical presentation, complication, treatment)
DEEP VEIN THROMBOSIS
Cause = venous stasis when sitting for long periods of time
Presentation
- pain, warmth, redness
- swelling of leg (can compress on nerves and cause numbness and weakness)
Complication
- thrombus can travel to lungs –> pulmonary embolism –> death
Treatment
- rivaroxaban/apixaban monotherapy
- LMWH + warfarin OR LMWH + rivaroxaban/dabigatran/edoxaban
State the cause and treatment of varicose veins
VARICOSE VEINS
Cause = valvular incompetency resulting in blood flowing from deep veins to the superficial veins through perforating veins
Treatment = polidocanol or mucopolysaccharide polysulfate
Common in posteromedial part of leg
State everything you know about poliomyelitis
(cause, presentation, treatment)
POLIOMYELITIS
Cause = polio virus attacks ventral horn of spinal cord
Presentation
- asymmetric flaccid paralysis without sensory loss
- reduces or absent deep tendon flexes
- systemic symptoms (fever)
TREATMENT
- 3x oral vaccination for children
State the pathogenesis and causes of trochanteric bursitis
TROCHANTERIC BURSITIS
Pathogenesis
- inflammation of the bursa which lies over the greater trochanter between the gluteus medius and gluteus minimus muscles
- thickening of the synovial membrane and increased fluid production
Causes
- friction from repetitive movement
- trauma
- RA
- septic bursitis
State the presentation of trochanteric bursitis
TROCHANTERIC BURSITIS
Presentation
- exacerbated by activity
- no reduction in ROM
- sleep disturbances
- pain on resisted adduction of hip
State everything you know about trochanteric bursitis
(pathogenesis, causes, presentation)
TROCHANTERIC BURSITIS
Pathogenesis
- inflammation of the bursa which overlies the greater trochanter of femur
- thickening of synovial membrane and fluid production
Causes
- friction from repetitive movements
- trauma
- RA
- septic bursitis
Presentation
- exacerbated by actiivty
- no reduction in ROM
- sleep disturbances
- pain on resisted adduction of hip
Recall the tendons that make up the pes anserine
- semitendinosus
- sartorius
- gracilis
State the difference between medial joint line OA and pes anserine bursitis
MEDIAL JOINT LINE OA (articular)
- medial joint line palpated above pes anserine
- passive and active movements are equally painful
- tender along joint line
- pain in all planes of joint movement
PES ANSERINE BURSITIS (peri-articular)
- palpate pes anserine on medial side of knee
- passive movements less painful than active movements
- tender in structure of involvement only
- pain in certain planes of movement
State the pathogenesis and presentation of baker’s cyst
BAKER’S CYST
Pathogenesis
- accumulation of synovial fluid in bursa between tendons of gastrocnemius and semitendinosus
- associated with RA, OA and meniscal tears
Presentation
- mild pain on knee flexion
- non-pulsatile swelling of popliteal fossa
State the causes, presentation, complication and investigations of diabetic foot ulcer
DIABETIC FOOT ULCER
Causes
- abnormal pressure or mechanical stress chronically applied to the foot
- peripheral neuropathy and arterial diseases
- altered metabolism
Presentation
- foul smelling ulceration
- not much pain sensation (due to DM having peripheral neuropathy)
Complication
- erosion of bone and OM –> amputation
Investigation
- swab after wound debridement –> bacterial culture
State the pathogenesis, clinical presentation and complication of dermatomyositis
DERMATOMYOSITIS
Pathogenesis
- inflamamtory myopathy characterised by inflammation and skin rash
- possible viral or autoimmune
Presentation
- arises in very young or old
- difficulty swallowing
- muscle weakness, stiffness, soreness
- violet-coloured upper eyelids
- violacceous skin rash
- SOB
- mechanic’s hands
Complication
- interstitial lung disease
State the investigations and treatments used for dermatomyositis
DERMATOMYOSITIS
Investigation - blood test positive for anti-jo1 antibodies
Treatment - corticosteroids
State everything you know about dermatomyositis
(pathogenesis, presentation, investigation, treatment)
DERMATOMYOSITIS
Pathogenesis
- inflammatory myopathy characterised by inflammation and skin rash
- possible viral or autoimmune
Presentation
- arises in very young or old
- difficulty swallowing
- muscle weakness, stiffness, soreness
- violet-coloured upper eyelids
- violacceous skin rash
- SOB
- mechanic’s hands
Complication - interstitial lung disease
Investigation - blood test positive for anti-jo1 ab
Treatment - corticosteroids
State what PVL stands for. State what PVL is.
PVL = panton valentine leukocidin
PVL is the virulence factor pdocued by some strains of MRSA that cause leukocyte lysis and necrosis
State the clinical presentation and complication of staph aureus infections for LL
STAPH AUREUS INFECTIONS
Clinical presentation
- systemic (fever, tachycardia, htn, low oxygen saturation)
- widespread macular rash
Complication
- septic shock –> multi-organ failure
- necrotising pneumonitis
- tissue necrosis
State the investigations for staph aureus infection of LL
STAPH AUREUS INFECTION
Investigation
- elevated lft (ast/alt)
- fbc (thrombocytopenia, leukopenia)
- elevated crp (c-reactive protein)
State the factors that maintain stability of hip joint
- depth of articular surface (acetabulum labrum deepens articular surface)
- surrounding muscles
- ligaments - ischiofemoral, iliofemoral, pubofemoral
State the common causes of posterior dislocation of hip
POSTERIOR DISLOCATION OF HIP
- dashboard injury - hip dislocated posteriorly
- medial rotation of foot and foot pointed medially
State the common presentations of posterior displacement of hip
POSTERIOR DISPLACEMENT OF HIP
- femoral head fracture
- compression of arteries resulting in avascular necrosis of head of femur
- post traumatic OA
- sciatica (L4-S3) –> weak knee flexion (hamstrings paralysed), muscles below knee paralysed, loss of sensation of almost whole leg, foot drop, foot inverstion (evertors paralysed), equinovarus
State everything you know about posterior dislocation of head of femur
(causes, presentation, investigation)
POSTERIOR DISLOCATION OF FEMORAL HEAD
Causes
- dashboard injury –> posterior dislocation
- medial rotation of foot and foot medially pointed
Presentations
- fracture of femoral head
- compression of arteries –> AVN of femoral head
- post-traumatic OA
- sciatica (L4-S3) –> weak flexion (hamstrings paralysed), all muscles below knee paralysed, loss of sensation of almost entire leg, foot drop, foot inversion (evertors paralysed), equinovarus
Investigation - X-ray of hip, CT scan
State the most commonly sprained ligament in the ankle.
State the less common ligaments that are also prone to sprain.
Most prone = anterior talofibular ligament (part of lateral collateral ligament when there is excess inversion)
Less prone
- posterior talofibular ligament
- calcaneofibular ligament
State the factors that contribute to ankle joint stability
- medial and lateral collaterla ligaments
- inferior transverse tibiofibular ligament (syndesmosis)
- tendons anteiror and posterior to ankle
- tiba + 2 malleoli tightly grip the talus to allow for stronger articulation
State the presentation and treatment of sprained ligament in ankle
SPRAINED LIGAMENT IN ANKLE
Presentation
- cardinal signs of inflammation (pain, loss of funtion, redness, swelling, fever)
- bruising due to hematoma in tissue surrounding joint
- patient initially able to walk but pain worsens a few hours after injury
Treatment - RICE (rest, ice, compression, elevation)
State the pathology behind meralgia parasthetica
MERALGIA PARASTHETICA = compression of lateral cutaneous nerve of thigh
State the clinical presentation of meralgia parasthetica
MERALGIA PARASTHETICA
Presentation
- numbness and burning sensation on lateral region of thigh
- no motor deficits since lateral cutaneous nerve is purely sensory
State the causes and presentation of common peroneal nerve palsy
COMMON PERONEAL NERVE PALSY
Cause
- compression of the head of fibula due to fracture
Presentation
- paralysis of dorsiflexors and extensors
- foot drop
- paralysis of evertors
- loss of sensation on lateral leg and dorsum of foot
State the difference between L5 radiculopathy and common peroneal nerve palsy
L5 RADICULOPATHY
- cannot abduct hip (L5 root involved in superiro gluteal nerve)
- cannot laterally rotate hip
COMMON PERONEAL NERVE PALSY
- press on fibular neck –> numbness and pain
- foot drop and inversion
- normal hip abduction and lateral rotation
State the difference betweeen L3 radiculopathy and femoral nerve palsy
L3 RADICULOPATHY
- obturator N affected –> adduction weak
- demratome distribution numbness smaller
FEMORAL NERVE PALSY
- adduction strong
- dermatome distribution larger
State the 7 non-traumatic causes of knee pain
- OA
- RA
- psoriatic arthritis
- osteomyelitis
- septic arthritis
- gout
- pseudogout
State the pathogenesis of pufferfish poisoning
PUFFERFISH POISONING
Pathogenesis
- pufferfish carry pseudoalteromonas tetradonis bacteria which produces lethal amounts of tetradotoxin in internal organs such as liver, ovaries and skin
- TTX block voltage-gated sodium channels found in axons of CNS and PNS –> stops nerve conduction
- TTX cannot cross BBB hence only affects PNS
State the clinical presentations and complication of pufferfish poisoning
PUFFERFISH POISONING
Presentation
- normal HR
- conscious
- numbness and wekaness in hands and legs
- shallow rapid breathing with low O2 saturation
- n/v + diarrhoea
- no reflexes
- hypotonia
- wasting and fasciculations
Complication - respiratory collapse
State the pathogenesis of compartment syndrome
COMPARTMENT SYNDROME
Pathogenesis
- swelling of muscles –> compression of blood vessels and nerves
- causesd by = direct trauma, burns, prolonged immobilisation post surgery, dehydration, DM, rhabdomyolysis
State presentation and treatment of compartment syndrome
COMPARTMENT SYNDROME
Presentation
- pain, swelling, redness, warmth
- ischaemia
- nerve damage
Treatment - fascietomy to relieve pressure and prevent further vessel and nerve damage
State the difference between soleus injury and gastrocnemius injury
SOLEUS INJURY
- same pain elicited on dorsiflexing foot when knee is extended and flexed
GASTOCNEMIUS INJURY
- easier to dorsiflex foot when knee flexed
