MSK Flashcards
Name some causes of posterior vertebral scalloping?
Intra dural spinal masses - ependymoma, NF1
Dural ectasia - Marfan’s disease, ehlers danlos
Congenital - achondroplasia
Name some causes of anterior vertebral scalloping?
AAA
Lymphoma
Downs syndrome
What is Kienbock disease?
AVN of the lunate.
Can be associated with negative ulnar variance.
What is Kümmel disease?
AVN of the vertebral body.
Usually with collapse and vacuum cleft
Causes of Chondrocalcinosis?
C,C,Cs
Crystals - gout, pseuodogout (COPD)
Cation - calcium, copper, iron
Cartilage degeneration - OA
What is the most common craniosynostosis?
Scaphocephaly
Premature closure of sagittal suture.
Elongated skull
What are the features of nail patella syndrome?
Hypoplastic nails
Hypoplastic patella - recurrent dislocations
Posterior iliac horns - Fongs prongs
Radiographic features of tenosynovial giant cell tumour?
Also called PVNS
Plain radio graph can have joint effusion
CT shows hypertrophic synovium, possible hyperdense due to blood.
MRI - Low T1 and low T2
What is Caplan syndrome?
Rheumatoid arthritis and pneumoconiosis.
Bilateral peripheral and upper lobe nodules that can cavitate
Osteoid osteomas are considered osteoblastomas when over what size?
> 2cm
Segond fracture is associated with rupture of what ligament?
Anterior cruciate ligament
What is a Clayshoveler’s fracture?
Fracture of the spinous process from hyperextension
What is a chance fracture?
Forceful flexion of the spine, causing anterior wedge compression fracture and fracture of the posterior elements.
Highly unstable.
What is a Jefferson fracture?
C1 blowout fracture due to axial loading i.e. jumping head first into a shallow pool
What is a hangman’s fracture?
Fracture of the bilateral pars of C2
What is Subacute Combined Degeneration of the spinal cord and it’s imaging appearance?
Vitamin B12 deficiency.
High signal in the posterior cord in an inverted V shape
What bacteria is associated with Guillain Barre syndrome?
Campylobacter
What is the most common spinal cord tumours in kids Vs adults?
Kids - Astrocytoma
Adults - Ependymoma
Which part of the scaphoid is most at risk of AVN?
Proximal pole
What is DISI?
Instability of the wrist where the lunate tilts dorsally.
Increased scapho-lunate angle >60⁰
(Scaphoid tilts volar normally, so as lunate tilts dorsally, the angle between them increases)
What is VISI?
Instability of the wrist where the lunate tilts volar.
Reduced scapho-lunate angle <30⁰
(Scaphoid tilts volar normally, so as lunate tilts volarly, the angle between them decreases)
What is a perilunate dislocation and what is it associated with?
Where the lunate stays put and the capitate dislocates.
Associated with scaphoid fractures
What are the associated injuries for positive and negative ulnar variance?
Positive - Lunate degeneration (Ulnar impaction syndrome)
Negative - Lunate AVN (Kienbock disease)
What is ulnar impaction syndrome?
Ulnar impacts the lunate, breaking the TFCC, and causing degeneration of the lunate
What is a Barton fracture Vs reverse Barton
Intra articular fracture of the distal radius extending to the dorsal surface. With dorsal radial carpal dislocation.
Reverse Barton is to the volar surface.
What is contained within the carpal tunnel?
FDP
FDS
FPL
Median nerve
What is a classic finding in TB tenosynovitis?
Diffuse tenosynovitis that spares the muscle.
Filling defects within the fluid called “rice bodies”
Where does De Quervain tenosynovitis typically affect?
First extensor compartment of the wrist.
Extensor pollicis brevis and Abductor pollicis longus
What is the difference between a Bennet’s fracture and a Rolando fracture?
Both are fractures of the base of 1st metacarpal (thumb).
Rolando fracture is comminuted.
What is Gamekeepers thumb?
Chronic avulsion fracture of the ulnar collateral ligament of the 1st MCP joint
Acute avulsion fracture is skiiers thumb.
Creates a Stener lesion if the adductor polisis muscle gets caught in the torn UCL.
Fracture of the proximal ulnar, with anterior dislocation of the radial head is what?
Monteggia fracture.
GRUesome MURder
G: Galeazzi R: radius fracture U: ulna dislocation
M: Monteggia U: ulna fracture R: radial head dislocation
Fracture of the distal radius, with dislocation of the ulnar carpal joint is what?
Galeazzi fracture.
GRUesome MURder
G: Galeazzi R: radius fracture U: ulna dislocation
M: Monteggia U: ulna fracture R: radial head dislocation
What is Little Leaguer’s Elbow?
Chronic injury to the medial epicondyle i.e. stress fracture, avulsion, delayed closure of the apophysis…
Where do complete biceps tear typically occur?
Avulsion off the labrum
What is associated with triceps rupture?
Salter Harris II fracture of the olecranon
What is the most common rotator cuff to tear?
Supraspinatus
What types of rotator cuff tears do you get and which is most common?
Articular (underside) - most common
Bursal (top side)
How bad does a rotor cuff tear need to be to require surgical intervention?
> 50% thickness
What is the classical imaging feature of adhesive capsulitis?
Thickened join capsule.
Decreased glenohumeral joint volume.
Loss of fat in the rotator cuff interval.
What are the types of Bankart lesions?
They are all injury to the labrum.
Perthes - detachment of the labrum, but intact periosteum
ALPSA - detachment of the labrum, intact periosteum, but medial displacement
Bankart lesion - detachment of the labrum, with broken periosteum
GLAD - Glenolabral Articular Disruption, labrum and ARTICULATAR CARTILAGE injury
What are the signs for quadrilateral space syndrome?
Compression of the axillary nerve in the quadrilateral space.
Atrophy of the teres minor muscle.
Name the attachments:
Illiac crest
ASIS
AIIS
Greater trochanter
Lesser trochanter
Ischial tuberosity
Pubic symphysis
Illiac crest - abdominal muscles
ASIS - Sartorius
AIIS - Rectus femoris
Greater trochanter - Gluteal muscles
Lesser trochanter - Illiopsoas
Ischial tuberosity - Hamstrings
Pubic symphysis - ADDuctors
What are the classic imaging features of Illiopsoas bursa?
Fluid collection anterior to the femur
What is a segond fracture and what is its association?
Avulsion fracture of the lateral tibial plateau
Associated with ACL tear.
What is the arcuate sign and association?
Avulsion fracture of the proximal fibula.
Associated with PCL tear.
What type of meniscal tear can form a bucket handle tear?
Vertical longitudinal tear.
What does the double PCL sign indicate?
Bucket handle meniscal tear
What is a Masonneuve fracture?
Widened medial malleolus/medical malleolus fracture + proximal fibular fracture.
What other injury is associated with bilateral calcaneal fractures?
Bilateral”Lover’s fractures” should prompt looking at the spine for burst fractures
What tendon does Os Peroneus lie within?
Peroneus Longus
What are:
Sequestrum
Involucrum
Cloaca
Sinus tract
Sequestrum - piece of necrotic bone surround by granulation tissue
Involucrum - thickened bone overlying chronic bone infection
Cloaca - defect in the periosteum caused by infection
Sinus tract - channel from bone to skin lined by granulation tissue
How do you differentiate Pott disease from bacterial discitis?
Pott disease is TB osteomyelitis.
Spares the disc space
Multi level involvement
Large paraspinal abscess
Develop “Gibbous deformity” (focal kyphosis caused by infection)
What are the different bone lesions that can have multiple fluid-fluid levels?
Telangiectatic osteosarcoma
Aneurysmal bone cyst
Giant cell tumour
How to differentiate Osteosarcoma from Ewing’s Sarcoma?
Ewing’s:
- Diaphysis femur
- Rarely calcifies
- Onion skin periosteal reaction
- Mets to bones and lung
Osteosarcoma:
- Metaphysis distal femur
- Amorphous calcification
- Sun burst periosteal reaction
- Mets to bones and lung with pneumothorax
How to differentiate enchondroma from chondrosarcoma?
Chondrosarcoma:
Cause pain,
Cortical destruction/scalloping,
Typically >5cm in size.
What are the epiphyseal lesions?
Chondroblastoma
Clear cell chondrosarcoma
Geode
GCT
Infection
What are the lucent bone lesions?
F - Fibrous dysplasia
E - Enchondroma, eosinophilic granuloma
G - GCT
N - NOF
O - Osteoblastoma
M - Myeloma, metastases
A - ABC
S - Solitary bone cyst
H - Hyperparathyroidism
I - Infection
C - Chondroblastoma
What are the two syndromes associated with polyostotic fibrous dysplasia?
MC Cune Albright - also gets Cafe au lait spots and precocious puberty
Mazabraud - also gets soft tissue myxomas
What is the difference between a NOF and a Fibrous Cortical Defect?
NOF are larger than 3cm
What is the difference between Olliers and Maffucci syndrome?
Both are multiple Enchondromas
Maffucci also have haemangiomas and increased risk of chondrosarcoma
What is the classical imaging appearances of a solitary bone cyst?
Fallen fragment sign.
Pathognomic signs of Pagets disease in:
Skull
Spine
Pelvis
Skull
- Tam O Shanter sign,
- Osteoporosis circumscripta
Spine
- Picture frame vertebra
Pelvis
- Pelvic brim sign
Classical imaging feature of Undifferentiated Pleomorphic Sarcoma?
Large soft tissue tumour.
Old people
Proximal limbs
T2 heterogenous/dark due to necrosis, haemorrhage, calc
Malignant transformation of benign tumours - Pagets disease, fibrous dysplasia, GCT, enchondroma
Classic imaging findings of Synovial sarcoma?
Young people
Periphal limb (Knee/foot)
T2 “triple sign” - necrosis, soft tissue, calc
Bowl of grapes - blood, fluid fluid levels
What are the differences between RA and Psoriatic arthritis?
RA - symmetric, proximal (MCP), osteoporosis instead of bone proliferation.
PA - Asymettric, distal (IPJs), boneproliferation instead of osteoporosis (periostitis), enthesitis.
What is Reiters triad?
Cant see, cant pee, cant climb a tree.
Urethritis
Conjuctivitis
Arthritis
What is Milwaukee shoulder?
Destructive shoulder arthropathy due to deposition of hydroyapatite crystals.
Classic imaging features of skeletal sarcoidosis?
Lace like honeycomb destruction of phalanges. Preservation of joint space
Lytic lesions in the skull and spine. Preservation of disc spaces
Most common skeletal abnormality in NF1?
Kyphoscoliosis
Classic imaging appearances of an intervertebral haemangioma?
Corduroy or jailbar appearance
(Axial CT will look like polka dots)
Classic location for a chondromyxoid fibroma?
Proximal tibial metaphysis
What is the treatment for osteoid osteomas?
Radiofrequency ablation
Which part of the spine does Ewing’s sarcoma affect most commonly?
1st Sacrum
2nd Lumbar
3rd Thoracic
4th Cervical
Classic imaging features of Rickets?
Fraying and cupping of the metaphyses.
Bowed legs with looser zones - pseudofracture of the compression side.
Classic spinal signs for achondroplasia?
Decreased interpeduncular distance
Anterior inferior bullet shaped vertebrae
Posterior vertebral scalloping
Gibbus deformity
First extensor compartment wrist
APL
EPB
De Quervain’s Tenosynovitis
Second extensor compartment wrist
ECR L
ECR B
Intersection syndrome
Third extensor compartment wrist
EPL
Drummer’s wrist
Traumatic rupture (distal radius #)
Fourth extensor compartment wrist
Extensor digitorum
Extensor Tenosynovitis
Fifth extensor compartment wrist
EDM
Vaughn Jackson syndrome
Sixth extensor compartment wrist
ECU
Snapping ECU
Most common type of tibial plateau fracture?
Schatzer II - splitting AND depression of the lateral tibial plateau
Classic knee xray findings of haemophilia?
Widened intercondylar notch
Squared inferior margin of the patella
Classic imaging findings of osteopetrosis?
Bone within bone appearance
Sandwich vertebrae
Erlenmeyer flask deformity
Where does the lisfranc ligament attach?
Medial cuneiform to 2nd metatarsal base
What is housemaids knee?
Pre-patella bursitis.
Most common site for mandibular fractures?
Mandibular condyle
Long bone appearance of skeletal lymphoma?
Lytic lesion with permeative bone destruction
Classic site for chondromyoid fibroma?
Proximal tibial metaphysis.
Classic imaging appearance of chondromyoid fibroma?
Proximal tibial metaphysis.
Eccentric.
Lytic.
Narrow zone of transition.
Geographic bone destruction.
General imaging features of fibrous dysplasia?
“Ground glass” matrix
Meta diaphyseal
Medullary
Expansile
Narrow zone of transition
Mixed cystic and sclerotic
Causes of ivory vertebra
LIMPHOMA
Lymphoma
Infection - TB
Metastases - Prostate/breast mets
Paget’s disease
Haemangioma
Osteosarcoma
MA - Mastocytosis
Classic imaging appearance of a brown tumour?
Cortically based
Lytic
Narrow zone of transition
No sclerotic border
What is SAPHO syndrome?
S: synovitis
A: acne
P: pustulosis
H: hyperostosis
O: osteitis
What is Madelung deformity of wrist?
Bowing of distal radius.
Positive ulnar variance.
V shaped carpal rows.
What are common hand xray findings in Turners?
Madelung deformity
3rd and 4th metacarpal shortening
Osteopenia
What is a Pilon fracture?
A pilon fracture is a type of distal tibial fracture involving the tibial plafond.
Typically high energy injuries and occur as a result of an axial loading which drives the talus into the tibial plafond.
Most common patella tumour?
Giant Cell Tumour
Chondroblastoma
How does LCH manifest in the skeleton?
Eosinophilic granuloma.
Skull - punched out lytic lesion, double contour sign.
Spine - vertebra planar
Long bones - Metadiaphysis, permeative. Can have soft tissue mass.
Typical imaging features of a chondroblastoma?
Epiphyseal
Lucent
Narrow zone of transition
Cloud like with rings and arcs
T2 LOW - The only epiphyseal lesion that is NOT high T2 signal
Features of acromegally?
Skull and spine:
- Calvareal thickening
- Vertebral body fractures without loss of mineral density
Hand and feet:
- Spade like phalanx
- Heel pad thickness >25mm
Imaging features of spontaneous osteonecrosis of the knee?
Acute onset of severe pain without significant trauma:
- Flattening of the medial femoral condyle
- Subchondral radiolucency
Most common cause of septic arthritis?
Streptococcus
Classic MSK presentation of haemochromotosis?
Hook like osteophytes, 2nd 3rd metacarpal
Chondrocalcinosis
Marked ulnar deviation at the MCP joints occurring post-rheumatic fever?
Jaccoud arthropathy
Ulnar subluxation and deviation at the metacarpophalangeal joints is correctable or reducible with physical manipulation
Iron deficiency anaemia MSK manifestations?
Hair on end appearance of skull
Osteoporosis of long bones
Secondary complications of Pagets disease?
Conductive hearing loss - otosclerosis
Hydrocephalus - basilar invagination
Osteosarcoma - 1% of patients
Features of Rheumatoid Arthritis?
Hands, elbows, shoulder
Hands:
- marginal erosion MCP joints
- juxta-articular osteoporosis
Elbows/knees:
- Joint effusion
Shoulder:
- Erosion of distal clavicle
What is a Stener lesion?
Caused by gamekeepers/skiers thumb (tear of the 1st MCP ulnar collateral ligament), when APL tendon gets caught in the torn ligament.
Will not heal by itself and needs surgical repair.
How do you differentiate between Morquio and Hurler syndrome?
Both are mucopolysaccharidoses (lysosomal storage disorder).
Both have platyspondyly.
Morquio has anterior CENTRAL vertebral body beaking.
Hurler has anterior INFERIOR vertebral body beaking.
Remember H comes before I (Hurler Inferior).
What is cherubism?
Variant of fibrous dysplastia
Bilateral expansile multiloculated cystic masses with symmetric involvement of the mandible and maxilla.
Types of tenosynovial giant cell tumour and most common joints affected.
Diffuse - knee joint most affected
Localised - fingers most affected
What is Caffey’s disease?
Infantile cortical hyperostosis
Self limiting disorder
Primarily affects the mandible
Periosteal reaction+ new bone formation
HOT on bone scan
Causes of vertebra plana
LL MMM
LCH
Lymphoma
Metastases
Myeloma
Medication - steroids
Causes of basilar invagination?
PARF (of least resistance)
Paget’s disease
Achondroplasia
Rheumatoid
Fibrous dysplasia
Describe the modic endplate changes
Modic 1 - oedema
T1 low
T2 high
Gd enhancement
Modic 2 - conversion to fatty marrow
T1 high
T2 high
Modic 3 - subchondral bony sclerosis
T1 low
T2 low
MRI findings of carpal tunnel syndrome?
Palmar bowing of the flexor retinaculum
Caliber change of the median nerve
Oedema or loss of fat in carpal tunnel
Most common cause of vertebra plana in children?
LCH
Imaging findings of dermatomyositis?
“Sheet like” calcification in the soft tissues
Associated conditions with dermatomyositis
Interstitial lung disease
Generalised increased risk of malignancy
Different subtypes of femoro acetabular impingement syndrome?
Cam type - anterior superior bump on femoral neck causing impingement
Pincer type - over coverage of the femoral head by the acetabulum causing impingement. (Coxa profunda, or protrusion acetabulum are potential causes)
How can you differentiate coxa profunda and protrusio acetabuli?
Protrusio acetabuli - the femoral head projects beyond the ilioischial line (i.e. into the pelvis)
What is Lofgren syndrome?
Systemic sarcoidosis
(LEAFgren syndrome)
Lymphadenopathy (hilar)
Erythema nodosum
Arthritis
Fever
What does erythema nodosum look like?
Painful red patches over the shins
Caused by panniculitis - inflammation of the subcutaneous fat
Causes of erythema nodosum?
Infection - TB
Inflammatory bowel disease
Sarcoid - Lofgren syndrome
3 stages of an intraosseous lipoma?
Majority found in lower limb metaphysis.
Stage 1 - Homogeneously fat signal
Stage 2 - Predominantly fatty with central calc or necrosis
Stage 3 - Heterogeneous, fat containing lesions, with extensive calc or necrosis
What is popliteal entrapment syndrome?
Intermittent claudication caused by compression or occlusion of the popliteal artery.
Usually by the medial head of gastrocnemius or popliteus muscle.
Long bone signs of Achondroplasia?
Long bones:
Symmetrical shortening of all long bones
Metaphyseal flaring
Trident hand (Spock hand)
Classic imaging features of scurvy (vitamin c deficiency)
Osteopenia
Periosteal reaction
Hemarthrosis
What is Sprengle deformity and it’s association?
Congenital elevation and rotation of the scapular.
Associated with Klippel Feil syndrome.
Imaging appearance of mastocytosis?
Bone bowel liver lymph
Bone lesions - lytic or sclerotic
Diffuse small bowel thickening
Hepato-splenomegaly
Lymphadenopathy
Kind of like a cross between myeloma and lymphoma
Skeletal manifestations of sickle cell disease?
Bone infarcts
Vertebral infarctions causing H shaped vertebrae
Hand foot syndrome - swelling of hands and feet caused by vaso-occlusive crisis
What are the Salter Harris fractures?
SALTR
I - Slipped epiphysis
II - Above (metaphyseal)
III - Lower (epiphyseal)
IV - Through (metaphyseal and epiphyseal)
V - Rammed (crush type)
Lucent bone lesions without a sclerotic rim?
BAG
Brown tumour
Aneurysmal bone cyst
Giant cell tumour
Which disease causes picture frame vertebrate Vs sandwich vertebrae?
Picture frame - Paget’s disease
Sandwich vertebrae - Osteopetrosis
C spine findings for JIA?
Atlantoaxial subluxation
Odontoid erosions
Facet joint fusion
What is Still’s disease?
Systemic onset Juvenile Idiopathic Arthritis
(Can occur in adults)
Still’s disease triad?
Salmon coloured rash
Arthralgia
Fevers
Skull signs for Achondroplasia?
Tiny cisterna magna (basilar invagination)
Large ventricles and supracella cistern
Increased tentorial angle (steep cerebellum)
What makes up the pes anserinus?
Anterior to posterior
(Say Grace Before Tea, Mum)
- Sartorius
- Gracilis
- Semitendinosus
(Semi membranosus is next)
