MSK Flashcards
What is DISH /
Diffuse idiopathic skeletal hyperostosis - anterior osteophtes spanning at least 4 vertebral levels with normal disc space and sacroiliac joints.
Associated with calcification of the posterior longitudinal ligament
What is kümmel disease ?
Gas within the vertebral body secondary to osteonecoriss from a compression fracture
What does the seagull sign refer to ?
erosive OA of the DIPJ - due to marginal osteophytes and medial erosion
In the hip joint, if there is AXIAL loss of space what does that usually mean ?
Associated with RA, however OA is still more common than RA in the hip
What is Protrusio deformity ?
More than 3mm or 6mm medial migration of the femoral head at the ilioishchial line
What joint is most commonly affected in the foot with RA ?
Metatarsalphalangeal joints
Which way do the joints subluxation in RA at the MCP ?
Ulna deviation
Why is only the inferior aspect of the sacroiliac joint affected in spodyloarthropathies ?
Because only the inferior portion is synovial.
What causes symmetrical sacroilitis ?
IBD associated arthropathy and ankylosing spondylitis
What causes asymmetrical sacroilitis ?
Psoriatic arthritis and reactive athropathy
What does the shiny corner sign signify?
Evolution of a prior Romans lesion
What is a Romanus lesion?
Erosion of the anterior/posterior edge of a vertebral body, early sign of a spondyloarthropathy
What is the dagger sign ?
Fusion of the spinous process - associated with ankylosing spondylosis
What other medical conditions is Ankylosing spondylitis assoicated with ?
pulmonary fibrosis
Aortitis
Cardiac conduction defects
What is the earliest signs of AS ?
Symmetrical erosions, widening and sclerosis of the sacroiliac joints
What is an Andersson lesions ?
Inflammatory involvement of the invertebrate disc by a spondyloarthropathy
Where does psoriatic arthritis commonly affect ?
The hands
What hands signs are classicaclly seen in psoaratic arthritis ?
Sausage digit
Pencil in cup
What conditions can lead to arthritis mutilans ? what is the classic hand finding ?
Psoriatic arthritis and rheumatoid
Telescoping of the fingers
What foot sign is seen in psoriatic arthritis ?
Ivory phalanx
What does reactive arthritis commonly affect ?
Knee, feet,
What is the key radiographic finding of SLE ?
Reducible subluxations of the MCP and PIP with abscence or erosive change
What is the characteristic sign of scleroderma ?
Acro-osteolysis - reabsorption of the distal portion of the distal phalanges + calcification
What type of crystals are deposited in calcium pyrophosphate ?
Rhomboid crystals are positively birefringent
What conditions are associated with calcium pyrophosphate ?
Haemochromatosis, hyperparathyroidism and hypophosphatasia
What causes osteomalacia ?
Most common is vitamin D deficiency
Which spinal cord lesions cause a dumbbell shaped tumour ?
Meningioma
Schwannomas
Neurofibromas
Ganglioneuroma
Neuroblastoma
What is the cockade sign ?
Calacaenal interosseous lipoma - well defined lytic lesion with central calcification
What is the arcuate sign ?
Avulsion fracture of the fibulae styloid - where the arcuate ligament attaches
This ligament is Y shaped and helps with knee stability
What radiological sign is seen in osteopetrosis ?
Bone within a bone - densely sclerotic bone
Which conditions can cause calcium pyrophosphate deposition?
Hemochromatosis, hyperparathyroidism, hypophosphatasia
What is the hallmark of gout ?
Marginated erosions with overhanging margins
What is the ultrasound sign for gout ?
Double contour sign - irregular hyperechoic line of urate crystals deposited on the hyperechoic cartilage
Where does gouty tophi like to develop ?
Olecranon bursa of the elbow
What is Calcific Tendinopathy ?
Deposition of calcium hydroxyapatite in tendons which are degenerating or hypoxia
What is the most common site of Calcific Tendinopathy ?
Shoulder
In the wrist which tendon is mostly affected by calcium hydroxyapatite deposits ?
Flexor carpi ulnaris tendon
What is Milwaukee shoulder ?
Intraarticular deposition of calcium hydroxyapatite, resulting in rapid destruction of the shoulder joint - including the rotator cuff and glenohumeral joint.
what percentage of patients with haemachromatotis develop arthropahty ?
50%
which organs are in the reticuloendothelial system ?
Spleen , liver suffer cells and bone marrow
what radiological sing in the hand might be present in haemochromatosis ?
hook like osteophytes at the MCP - can involve all of them
what happens to the joint space in early acromegaly?
widened joint space
what hand features suggest acromegaly ?
spade like tuffs
beak like osteophytes of the metacarpal heads
who is at risk of amyloid arthroapthy ?
patients on chronic hemodialysis - with chronic renal failure
what is the shoulder pad sign and what arthropathy is it associated with ?
predominance of the anterior deltoid - seen in amyloid athropathy
a patient with intervertebral disc calcification at ever level with mild disc loss height has what ?
ochronosis / alkaptonuria
if there is bilateral ankle arthorsis and erythema nodosum - what should you be worried about ?
sarcoidosis
what hand features might be seen in sarcoid?
lace like lytic lesions in the middle or distal phalanx
MSK - what does haemophilia tend to affect.
knees, elbows , ankles
what is the characteristic features of haemophilia in the elbow?
enlarged radial head and widened trochlear notch
in juvenile idiopathic arthritis, where might ankylosis occur ?
in the cervical spine or the wrist
what is the differential for ankylosis of the cervical spine ?
juvenile idiopathic arthritis and klippel-feil syndrome
what is klippel feil syndrome ?
failure of cervical segmentation
what is the most common cause of shoulder neuropathic athropathy ?
syringomyelia
What are the three most common cause of Charcot joint ?
- Diabetes
- Syringomeylia
- Leprosy
Which arthritis cause demineralisation ?
HORSE
Haemophilia
Osteomalacia
Rheumatoid and Reuters
Slceroderma
SLE
Which arthritis doesn’t cause demineralisation ?
PONGS
Psoriatic
Osteomyelitis
Neurogenic
Gout
Sarcoidosis
What joint is most commonly affected in SAPHO ?
Sternoclavicular joint
What does SAPHO stand for ?
Synovitis
Acne
Palmoplantar pustulitis
Hyperostosis
Osteoiditis
What is Gardner syndrome ?
Osteomas
Intestinal polyps
Soft tissue desmoid tumours
Where doe osteomas arise from ?
The bony cortex
Where do bone islands arise from ?
The medullary canal
What is the classic appearance seen in melorheostosis
Candle wax appearance - irregular sclerosis of the bony cortex- usually affected by a single sclerotome
What sign on nuclear medicine is seen with an osteoid osteoma ?
Double density sign
Where does osteosarcoma tend to metastasise to ?
The lungs
What are the 4 main subtypes of osteosarcoma ?
- Periosteal - inner periosteum
- Paraosteal - outer periosteum
- Telangectatic osteosarcoma
- Conventional
What is the most common subtype of osteosarcoma ?
Conventional 75%
What is the classic feature of paraosteal osteosarcoma?
A type of osteosarcoma that arises from the outer layer of the periosteum.
Cauliflower outgrowths
What is olliers syndrome ?
Multiple enchondromas
What is maffucis syndrome ?
Multiple enchondromas and vascular malformations results in phleboliths
In the pelvic bones, what does fibrous dysplasia look like ?
Cystic lesions
what usually happens to non ossifying fibromas ?
Usually spontaneously scerlosis once they reach adulthood
what is McCune-Albright Syndrome ?
polystotic fibrous dysplasie
cafe au lait spots
precocious puberty
what is Mazabraud syndrome
fibrous dysplasia
Intramuscular myxomas which tend to occur in the same part of the body
which conditions are associated with giant cell tumour ?
hyperparathyroidism
pagets disease
what causes eosinophilic granuloma ?
proliferation of histiocytes
what might Langerhan cell histocytosis look like on skull x-ray if it affected the mandible or maxilla ?
floating teeth
what does Ewings sarcoma originate from ?
small round cell tumours
how might patients with Ewings sarcoma present ?
pain, fever, raised ESR
what is the most common primary malignant bone tumour in patients over 40 ?
Multiple myeloma
Why do you get H shaped vertebrae in sickle cell anaemia ?
central end plate infarction, non-involement of the periphery
what are the main causes of H shaped vertebrae ?
Sickel cell diseae
Gaucher diseae
What is a clinical feature of osteogenesis imperfects ?
Deafness.
Blue sclera
Normal life expectanacny
Usually present 2-6 yrs old
Which arthropathy is most associated with HLA-B27 ?
1.Ankylosing spondylosis
2. Enterocolic spondylosis
which metastases are mainly lytic ?
Lung
breast
thyroid
kindy
stomach
which mets are mainly blastic
breast
prostate
TCC
Mucinous tumours
carcinoid
what is myositis osifficans ?
bone forming in the soft tissue, usually after trauma, may look like an osteosarcoma
which patients get brown tumours ?
hyperparathyroidism
what do myxoid liposarcomas look like ?
large homogenous hyperintesnse mass on T2 , may not show any fat
what features would make you more concerned about a liposarcoma vs a lipoma ?
nodular enhancement
thickened septa
increased size
what is the most common site for fibrolipomatous harmatoma ?
median nerve
what is the pathognomic feature of fibrolipomatous hamartoma of nerve ?
cable like appearance
Fibrolipomatous harmatoma of a nerve is fatty infiltration and enlargement of the nerve fibres, this causes it to look like a cable full of wires. often affects the median nerve
what is ledderhose disease
fibrzomatosis of the foot
where do elastofibroma dorsi typically occur ?
sub scapular region
what syndrome is associated with Desmond fibrzomatosis ?
Gardner syndrome
what is Mazabraud syndrome
fibrous dysplasia with intramuscular myxomas
What percentage of fracture can be identified by MRI ?
90%
What is a Segond fracture ?
An avulsion fracture of the tibial plateau - on the lateral aspect, and usually involves the the ACL
If suspecting a tibial plateau fracture - what is the best imaging modality ?
CT
What imaging mri sequences should you do for Knee trauma ?
T2*, PD , Fat sat or STIR, T1.
T1 will show fracture lines
STIR - for oedema
Where does the lateral collateral ligament and biceps femora’s attach ?
Fibular head
What attaches onto the lateral aspect of the tibia ?
The iliotibial band , capsule, and anterior oblique band of the lateral collateral ligament
What is a Segond fracture ?
An avulsion fracture of the lateral aspect of the tibial plateau - associated with an ACL rupture
What mri sequence should you be looking at the ACL ?
T2
As PD wont be accurate
In a patella dislocation, where might you find a micro fracture ?
Patella always dislocates laterally, The patella impacts on the way back causing whacking
Bone bruise lateral femoral condole and medial patella
What injury is assoicated with a patella dislocation ?
Medial patella retinaculum injury
Osteochondral fracture patella
What causes locking of the knee >
Bucket handle tear of the meniscus
Medial collateral ligament
What are the 3 shapes of meniscal teas ?
Longitudinal, radial, horizontal
What are the 3 types of displaced meniscle tears >
Parrot beak,
Bucket handle
Flap tear
What is frozen shoulder
GHJ capsulitis - loss of external and internal rotation
What does supra and infra spinatous attach to ?
The greater tubercle of the humerus
What does the empty notch sign indicate
FLuid between the lateral aspect of the intercondylar notch - this is where the ACL should be, and it indicated an injury to the acl
What is an effective treatment for frozen shoulder
Steroid injection and hydro-dilatation
What is barbotage used for ?
Calcific tendinitis - washing a calcified tendon
What is the criteria for hip replacement ?
Night pain
What is the most common sequence for prostate cancer bone mets ?
Pelvis, spine then ribs
What is Barstraps disease ?
kissing spines) is a cause of low back pain characterised by interspinous bursitis and other degenerative changes of the bones and soft tissues where adjacent spinous processes in the lumbar spine rub against each other.
What causes
Osteitis condensans ilii
What will a normal thrombus look like on a. PET CT?
Photopenia in the blood pool
What does a haemangioma look like ?
High T1, Hight T2, drop out on STIR
If a lesion has signal drop out of >20% what would you think it is ?
Fat containing - likely haemangioma
Causes of bone marrow replacement
Bone marrow hyperplasia
Bone marrow infiltration
haematological diseae
metabolic disease
renal osteodrystrophy
What would a bone island look like on MR ?
Jet black on all sequences
What does pure bone marrow oedema look like on T1 ?
Patchy low signal
What should you be concerned of with a lesser trochanter avulsion ?
Metastasis
What should you do with a lesions with rings and arcs ?
Chondroid lesions - should all be MR
What is the size criteria for enchondromas ?
< 4cm
what condition is the bulls head see on nuclear medicine scan
SAPHO
S: synovitis
A: acne
P: pustulosis
H: hyperostosis
O: osteitis
what sesamoid bone lies within the lateral head of gastrocnemius ?
flabella
what are the components of the rotator cuff ?
supraspinatous
infraspinatous
subscapularis
teres minor
what connects to the lateral menisucus ?
nothing
when damage to the medial collateal ligament what other injury is likely ?
likely injury to the medial meniscus - as the meniscus and collateral ligament are attached
what is a rolando fracture
Comminuted, intra-articular fracture at the base of the thumb
what is osteomalacia?
low bone mineralisation
in osteomalacia where do loser zones typically appear ?
Losser zones are insufficiency fractures - usually occur where blood vessel transverse the bones. Often they are found in :
neck of femur
pubic rami
lower ribs
scapula
in rickets- which part of the bone is prone to most changes ?
the metaphasis as it has the most growth
what features of rickets might you see ?
frayed metaphyseal margin - at the wrists
Widened growth plate
Cupping/splaying metaphysis due to weightbearing - at the femur
Enlargement of anterior ribs. Rickety rosary
Osteopenia
what are looser fractures?
stress fractures caused by normal stress applied to abnormal bone.
what are brown tumours ?
large areas of cortical , subcortical and meduallary bone reabsorption
what are the features of renal osteodrystrophy ?
rickets - looser zones
secondary HPT - soft tissue calcification, chondrocalcinosis and nephrocalcinosis
Osteosclerosis
Osteoporosis
why do you get osteosclerosis in renal osteodystrophy?
due to aluminum toxicity in haemodialysis
what conditions result in fusion of the spine?
ankylosing spondylitis
poliomyelitis
juvenile chronic arthritis
what radiological features might you see in alkaptonuria ?
Bamboo spine without osteophytes
calcification of the intervertebral ligaments
in children, is cervical disc calcification a problem>
no, usually self resolves
what do bony lesions in gout usually look like ?
intra or extra articular, well defined erosions with sclerotic margins and an overhanging edge.
the joint space is usually well persevered.
in CPPD which ligament is commonly calcified ?
triangular fibrocartilage complex
which arthropathy stains with Congo red ?
amyloid arthropathy
what is the intravertebral vacuum clef sign pathognomic for ?
calve kummel verneuil disease
osteonecrosis and collapse of a vertebral body
what is Kohler disease ?
avascular necrosis of the tarsal scaphoid
what is kienbocks disease ?
AVN of the luate
which is Freiberg disease ?
AVN of the metatarsal heads
what is clave perthes disease?
AVN of the femoral head
what is scaphocephaly and what is it associated with ?
premature closure of the sagittal sinus which stops lateral growth. There is ongoing A->P growth which causes the head to become long and thin. This is assoicated with marfans syndrome
what is pathagomoic of nail-patella syndrome (Fong disease)
bilateral, symmetrical posterior iliac horns
what are the classic features of pagets disease?
Osseous expansion, coarsened trabeculation and thickening of the cortex
which areas are commonly affected with pagets disease ?
skull, long bones, ribs, pelvis, and spine
what is pigmented villonodular synovitis ?
benign proliferative condition affecting the synovium. this causes proliferation and haemosiderin deposits
what is caplans syndrome
RA plus lung fibrosis - nodular pattern
what is feltys syndrome ?
RA plus splenomegaly and neutropenia
what are the causes of a positive bone scan with a normal radiograph ?
lymphoma
pagets disease
osteomyelitis
primary hyperparathyroidism
what are the causes of an abnormal radiograph but a normal bone scan
acute fracture <48 hours
multiple myeloma
metabolically inactive benign conditions (bone island, exostoses, bone cysts)
osteoporosis
mets - with no osteoblastic activity
what are the features of a giant cell tumour ?
eccentrically located lesion, usually at the end of long bones. The bones have closed growth plates. They extend into the epiphysis and subchondral bone.
Locally aggressive but rarely malignant
what is the most likely mechanism of a triquetral fracture
falling onto an outstretched hand in ulnar deviation
which ligament is injured in the ‘game keepers’ or ‘skiers’ thumb ?
ulnar collateral ligament
what are chondroblastomas ?
benign tumours that arise from the epiphysis of young children - not fused.
what are patients with pages disease at risk of developing ?
osteosarcoma
what patients develop brown tumours ?
people with underlying hyperparathyroidism
which part of the spine is most likely to be affected in Ewings ?
sacrum
what is the condition con multiple hereditary osteochondromas ?
diaphysial atlasis
where are spinal ependymomas most likely to occur ?
in the cervical spine
what is a chondroblastoma ?
a bening cartilage forming tumours arising in skeletally immature patients. often occurs in the humerus. arises from the epiphysis ( this can include the patella)
what bone lesions are patients with hyperparathyroidism at risk of?
brown tumours
what condition is associated with absent clavicles. wormian bones, facial abnormalities
cleidocranial dysostosis
what is an adrenal myolipoma
an adrenal mass, fat containing (so low HU) often bleed if >4cm - so increased risk of retroperitoneal hamerrahae
why do you get abnormal scalloping of vertebrae
either a mass causing pressure effects on normal bone
or normal CSF movement casuing pressure effects on abnormally soft bone
what causes anterior scalloping of the vertebrael body
Enlarged retroperitoneal lympho nodes - lymphoma TB
or AAA
what causes posterior scalloping of the vertebral body
dural ectasia (NF1)
spinal mets
Achondropalsia
acromegaly
mucopollysaccahrides
what is Klippel-Feil syndrome
vertebral segmentation anomaly, causing fusion or one or more vertebral bodies
what other conditions is AS associated with ?
aortitis
pulmonary fibrosis
cardiac conduction defects
