MCQ Flashcards
1
Q
TB v pyogenic discitis
A
TB: multiple levels (5-10), skip lesions, no reactive sclerosis, disc spared until late, gibbus deformity as preference for anterior endplates, can cause ivory vertebra, vertebra plana, erosions generally present by presentation. Tends to be thoracic
Pyo: Staph in 60%, strep viridans in IVDU, gram negatives. Tends to be lumbar
IVDU can have funny organisms
2
Q
Sympathetic dystrophy
A
Osteopaenia
Subperiosteal bone resorption
Soft tissue swelling, eventually atrophy
Preserved joint space
Three phase increased uptake on NM
Patchy subcortical bone marrow oedema on MR, and soft tissue oedema / enhancement
3
Q
NF1 MSK manifestations
A
Increased risk of rhabdomyosarc, leiomyosarc Ribbon ribs Vertebral scalloping Tibial or ulnar pseudoarthrosis Limb bowing Rib notching
4
Q
Fluid-fluid level bone lesions
A
ABC, which may be primary or secondary to: GCT, fibroxanthoma, chondroblastoma, osteoblastoma,
UBC, esp after fracture
Telangiectatic osteosarc
Uncommon causes: mets (esp RCC, lung), synovial sarc, synovial haemangioma, myositis ossificans, adamantinoma, neurogenic tumour
Mnemonic: GOATS CSF
GCT, osteoblastoma, ABC, telangiectatic osteosarc, sarcomas, chondroblastoma, solitary bone cyst, fibroxanthoma
5
Q
SLAC wrist
A
Most commonly from scapholunate ligament injury but also
Typically found in CPPD
Progressive wrist OA pattern - starts at radioscaphoid, then involves capitolunate and DRUJ and others.
6
Q
Osteoid osteoma
A
Usually cortical but can occur anywhere in bone (medullary, within joint capsule)
Central lucent nidus may have some central mineralisation
Surrounding sclerosis - medullary lesions may not have sclerosis.
Can occur in posterior elements, fingers, but big long bones most common (50% lower limb - blastoma more frequently spine, does not induce marked bony reaction)
Double denstiy sign on NM (not donut, which is activity around lucent centre, e.g. ABC, UBC, GCT)
Surgical resection was traditional management. Now RF ablation.
Male prediliction
Nidus is bone at various stages of development in a highly vascularise connective tissue stroma
Sclerosis less in medullary and intracapsular lesions
Can cause leg length discrepancy
7
Q
Major bone bruising patterns
A
Lateral patellar dislocation - self explanatory
Pivot-shift - Posterolateral tibial plateau and mid lateral femoral condyle - ACL tear associated (may also have postero medial tibial plateau)
Clip
Hyperextension
Dashboard
Median time to resolution of 42 weeks. Influenced by presence of OA.
8
Q
ACL injury
A
Segond fracture (probably lateral capsular liagment but may be ITB or other - LCL)
Arcuate sign - avulsion of tip of fibula from arcuate ligament
Bone bruising pattern
Anterior drawer sign (7mm)
ACL should be steeper than intercondylar roof
Anterior ligamentous border may appear concave
Associated with MCL injury
PCL angle may be reduced on MR
May have meniscal tear or meniscocapsular separation (posterior horn medial meniscus)
Associated with meniscal tears lateral > medial in 65%
Associated with posteromedial corner injury, and posterolateral
9
Q
Scapholunate angle
A
30-60 degrees
Increased in scapholunate dissociation and DISI
Decreased in VISI
10
Q
Capitolunate angle
A
<30
Increased in both VISI and DISI
11
Q
Scapholunate dissociation
A
Scapholunate interval >4mm (or 3mm)
Exacerbated by clenched fist views and PA with ulnar deviation
Also increased scapholunate angle
Risk of SLAC wrist
12
Q
Perilunate dislocation
A
60% associated with scaphoid fracture and termed trans-scaphoid perilunate dislocation
Carpus tends to dislocate dorsal relative to lunate - normal radiolunate articulation
Reduce scapholunate angle, increased capitolunate angle
13
Q
Carpal instability (perilunate instability)
A
1 - scapholunate dissociation
2 - perilunate dislocation
3 - midcarpal dislocation - 2 + lunotriquetral ligament injury or triquetral fracture
4 - lunate dislocation
14
Q
VISI and DISI
A
Scapholunate angle is increased in DISI and decreased in VISI
Capitolunate angle increased in both
Lunate tilts dorsally in DISI, volarly in VISI
15
Q
Bohler angle
A
20-40
Less than 20 in calcaneal fracture
16
Q
Morton neuroma
A
Perineural fibrosis around an intermetatarsal nerve
Low MR signal with intense enhancement
Well defined and hypoechoic on USS
10% bilateral
Intermetatarsal nerve lies plantar to the deep intermetatarsal ligament
17
Q
Muscle denervation
A
Early increased T2, best seen on STIR
Chronic increased T1
18
Q
Sinus tarsi syndrome
A
Lateral hindfoot pain between ankle and heel
Sinus tarsi separtes anterior and posterior subtalar joints, and is positioned laterally
Inflammation, fibrosis, or ligamentous disruption - T1 hyperintense fat is replace by fluid or fibrosis
19
Q
Rotator cuff
A
Supra - abduction
Infra and teres - ext rot
Subscap - int rot
Supra tears occus in critical zone, 1cm from insertion, relatively hypovascular, and start anterior and propogate posterior
Bursal fluid is sensitive but not always present
Full thickness tears in 30% of >80 with minimal functional impairment
Joint effusion not present in majority
Subdeltoid fat plane an unreliable indicator
<7mm acromiohumeral distance in tear
20
Q
Shoulder ultrasound
A
Supra - shoulder internally rotated and extended (arm behind back) (note calc better seen in external rotation on xray)
Infra - hold opposite shoulder - internal rotation and flexed (arm on opposite shoulder)
Teres - doesn’t seem to be part of normal protocol
Subscap - externally rotated, elbow at 90 degrees
Biceps - supinated, elbow flexed 90 degrees
21
Q
Posterior element lesions
A
GCT Osteoblastoma TB ABC Pagets Eosinophilic granuloma (Goat PE - not goats csf which is fluid fluid level)
22
Q
Carpal ossification
A
Start at capitate and go anticlockwise (right) but skip pisiform which is last Capitate Hamate (both 1st year) Triquetrum Lunate (both 2-4 years) Scaphoid Trapezium Trapezoid (three are 4-6 years) Pisiform (8-12 years)
23
Q
Myositis ossificans (circumscripta)
A
Peripheral calc at 4-6 weeks
cf osteosarc (parosteal) where calc starts centrally
Can have fluid levels
Post traumatic
Myositis ossificans progressiva is a rare hereditable conditions, separate, with progressive ossification of muscles, fatal at 45, with microdactyly and progressive fusion of cervical spine (facet joints), monophalangic 1st toe
24
Q
Reiters
A
Bony proliferation (like psoriatic) - enthesopathy or periostitis (and parasyndesmophytes) Can cause acro-osteolysis
Salmonella, yersinia, shigella, campylobacter, E. coli, chlamydia
Predominantly feet, with appearance similar to psoriatic
Calcaneus in particular
25
Chondromyxoid fibroma
Lucent, eccentric, metaphyseal
Benign
Differential of ABC, GCT, NOF (younger), chondroblastoma
26
DISH
Flowing osteophytes (and calc, at least 4 contiguous vertebrae)
Commonly thoracic spine, and also cervical
No disc-space narrowing
Lack of facet joint arthropathy
Fusion of non-synovial superior SI, and sympysis pubis
Lateral acetabular osteophyte
Enthesopathic bony proliferation
Retinoid therapy can give similar appearance (favours cervical)
Fluorosis also in differential
Ossification of iliolumbar, sacroiliac and sacrotuberous ligaments
27
Tarlov cyst
Most common at S2-3
May cause erosion
Symptomatic in 20%
28
Disc disease
Bulge if >90 degrees, circumferential or asymmetric
29
CPPD
1/8 have pressure erosions from the crystals
30
Osteoporosis / paenia
T score - compared to 30yo
Z score is age adjusted
Each SD change in T doubles fracture risk
T <2.5 is porosis, 1-2.5 is paenia
31
Osteoblastoma
```
Rare to involve sacrum (although radiopaedia says 17%)
May be blastic or lytic
Doesn't respond well to salicilates
50% have speckled calcification
Pronounced NM uptake >80%
```
40% spine
Otherwise diaphysis and metaphysis of long bones
Typically larger than 2cm
32
Marrow conversion
Begins peripherally
Epiphysis then diaphysis then metaphysis - distal then proximal
Red marrow confined to axial skeleton by 25
Islands of red marrow, particularly subcortical or subchondral in proximal humeri and femora
33
Osteosarcoma
4% extra-skeletal, 80% intramedullary (conventional, low grade, telangiectatic), 15% surface
50-55% of conventional are around the knee
Tend to be metaphyseal (90-95% conventional) (or metadiaphyseal)
15% of all primary bone tumours (2nd after myeloma)
Parosteal often posterior distal femur 60% - 30-40% have lucent line separating from bone - lowest grade with excellent prognosis. Early adulthood and middle aged.
Telangiectatic fluid levels in 90%
Periosteal often diaphyseal, esp. anteromedial diaphysis of proximal tibia, medial distal femur (most common). (parosteal is still metaphyseal, like others)
Slightly older than conventional, but not as much as parosteal or gnathic.
Parosteal more common than periosteal
Parosteal - outer fibrous layer of periosteum
Periosteal - inner germinous layer of periosteum
Gnathic are older patients - 30-40, slightly male
34
Snapping hip
Thickened glut max aponeurosis over greater troch
35
Periarticular osteopaenia
RA, reactive arthritis, septic arthritis, scleroderma, SLE
36
Radiation induced bone tumours
Osteochondroma most common benign
Osteosarc most common malignant (90%)
Also fibrosarc, malignant fibrous histiocytoma
Lag time of 11-14 years
Arise in areas of pre-existing radiation change
37
Radiation osteitis
Potentially reversible changes e.g. temporary cessation of growth, periostitis, sclerosis, fragility
38
Meniscal cyst
Associated with complex tear, radial split tear, radial + horizontal (mostly those with a horizontal component)
Medial:lateral 2:1 (Some literature says equal, Radiopaedia says possibly lateral more common)
Medial mostly posterior (same with tears), lateral mostly anterior - LAMP
39
O'Donoghue's triad
ACL tear
Medial meniscal tear
MCL tear
40
Patella dislocation
Patella alta predisposes - long tendon
41
Tarsal coalition
Bilateral in 50%
90% talocalcaneal or calcaneonavicular
Talocalcaneal best seen on coronal CT, lateral radiograph - middle facet
Calcaneonavicular best on T2 sag MR, oblique radiograph
Cartilaginous, bony, or fibrous, oedema adjacent to fibrous
42
Norgaard view
AKA ballcatcher view
43
SLE
May cause avascular necrosis secondary to steroids and vasculitis
44
Avascular necrosis
```
STARS
Steroids
Trauma
Alcohol
Radiation (RA)
Sickle cell
```
Also Gauchers, pancreatitis, SLE, Caissons,
```
ASEPTIC
Anaemia - sickle cell
Steroids (sickle cell, SLE)
Ethanol
Pancreatitis, pregnancy
Trauma
Idiopathic, infection
Caisons, connective tissue disease (includes SLE, RA)
```
45
Spondyloepiphyseal dysplasia
Dysplasia, spine and proximal epiphyseal centres
Abnormal collagen synthesis
Congenital and tarda forms
Short proximal limbs, normal size hands and feet
Coxa vara, flattened femoral head
Atlantoaxial instability
Craniovertebral junction stenosis
Scoliosis
Platyspodyly
Short neck and short trunk with protruding abdomen
Normal IQ and life span
Associations: myopia, retinal haemorrhage, hearing loss, nephrotic syndrome
46
Cortical desmoid
Misnomer
High T2, enhances
Normal or increased bone scan uptake (eventually becomes cold)
Adductor magnus or medial gastroc insertion
Adolescents, slightly more in males
Usually asymptomatic but may cause pain
Saucer shaped radiolucent cortical irregularity posteromedial femur
May have periosteal new bone
47
Melorrheostosis
Associated with by vascular and lymphatic tumours
And by overlying skin and muscular changes - scleroderma, hyperpigmentation, muscle atrophy, contractures
Dripping candle wax sclerosis
Periosteal cortical thickening, may be endosteal also. Thick, undulating ridges of bone.
Tends to be monomelic, may be mono or polyostotic. (confined to sclerotome)
May have osteosarc of MFH, possibly (according to radiopaedia, although only vascular malformations mentioned in Dahnert)
Axial skeleton rare
May require tendon release, osteotomy, amputation
27% ossified soft tissue masses
May cross a joint, with fusion
May coexist with osteopathia striata (celery stalk metaphyses - also see these with rubella) and osteopoikilosis
48
Acromion types
1 flat
2 concave down
3 hooked down
4 convex down
3 has highest rate of rotator cuff tears (associated with impingement)
4 has not been assoicated with impingement
Os acromiale increase risk of impingement - bilateral in 60% (although no difference in tear rates)
49
Magic angle
55 degrees to magnetic field
Bright on Short TE (PD and T1), disappears on T2
Due to orientation of collagen bundles
Common locations: proximal PCL, patellar tendon tibial insertion, peroneal tendons around lateral malleolus, supraspinatus, TFCC
50
Multiple myeloma staging
1-3
1: < or = 1 plain film lesion, normal calcium, small amount of monoclonal antibody in blood/urine, small number of myeloma cells, slightly decreased RBC
3 - > or = 3 lesions, hypercalcaemia, large monoclonal antibody, severe anaemia, large number of myeloma cells
51
Chordoma
Mets can be intradural (drop) or intraosseous (lung and bone mets are rare)
Physaliferous cells - bubble like vacuolated - cords and clusters
Lobulated tumour with pseudocapsule
Bone lesions with large soft tissue mass
Most common primary malignant tumour of spine exc lymphoproliferative
Rare <30
Main differential is chondrosarcoma
Calcify
Heterogeneous MR signal
52
Craniocervical junction assessment
BDI < 12mm xray, 8.5mm CT
BAI (to posterior dens) < 12mm
Anterior atlantodens <2mm (<5mm in children)
Lateral 2-3mm difference
Occipital avulsion fractures are associated with atlanto-occipital instability
53
Cervical spine radiograph children
Atlantoaxial subluxation 5x more common in children
Anterior wedging of C3 normal variant
Up to 6mm C1 overhanging C2 laterally in a 4 year old
SCIWORA 5-65% of injuries - can have delayed onset, up to 48 hours
(SCIWORA associated with hyperextension)
Cervical facet joints are more horizontal in young children
54
Lucent transverse metaphyseal bands
```
LINING
Leukaemia
Illness - scurvy, rickets
Normal variant
Infection - congenital syphilis, TORCH
Neuroblastoma mets
Growth lines
```
55
Dense metaphyseal bands
```
LINES
Lead poisoning
Infection (TORCH)
Neoplastic- lymphoma, leukaemia
Endocrine (congenital hypothyroidism)
Scurvy, sickle cell, syphilis
```
56
Femoral head AVN
Anterior weight bearing portion affected first
Cartilage intact until late
MR more sensitive than bone scan
57
Toddler fracture
Tibial, calcaneal, cuboid, fibula
58
Achilles
Tear 2-6cm proximal to calcaneal insertion, or at myotendinous junction
Anterior margin usually flat or concave - if convex tendon is thickened (posterior margin is convex)
1mL fluid in retrocalcaneal bursa normal
No tendon sheath, so can't have tenosynovitis
Should be low signal on all sequences.
May have magic angle (T1 and PD - not T2)
Chronic tendinopathy has thickening without necessarily increased signal - increased signal in tear
59
Scaphoid fracture
Proximal third - 20%, 90% fail to unite
Middle third - 60%, 30% fail to unite
Distal third - 20%, unite
Overall the requisites suggest only 10% fail to unite.
AVN risk if non-union, of proximal pole.
Displaced and unstable fractures require fixation
60
UBC
Young patients - long bones, esp humerus, then femur
Older, flat bones (and e.g. posterior elements)
Intramedullary, metaphyseal, abut growth plate
Migrate to diaphysis with time
Fallen fragment sign 20%
61
Path fracture paeds
```
UBC (40%)
Non ossifying fibroma (19%)
Fibrous dysplasia (16%)
Osteosarcoma (15)
ABC (10%)
```
62
Down syndrome
```
Flared iliac wings with small acetabular angles
Increased iliac angle
DDH
SUFE
Atlantoaxial subluxation in 25%
11 ribs
Persistent metopic suture
Wormian bones
Hypersegmented manubrium
Clinodactyly
Hypoplasia of middle phalanx of 5th
```
63
Fibrous cortical defect
```
2-10 years
T1 hypo, T2 variable
Multiloculated
Cortical
Can be expansile
Thin rim of sclerosis
No periosteal reaction
Most commonly distal femur
Metadiaphysis / diaphysis
Involute over 2-4 years
Asymptomatic
```
NOF > 3cm
NOF vit D resistant hypophosphataemic rickets
Male prediliction
associated with fibrous dysplasia, NF1, and Jaffe camanaci
64
Shepherd fracture
Fracture of lateral tubercle of posterior proces of calcaneus
Inversion in extreme equinus
65
Cervical flexion teardrop
Unstable
Associated with ventral cord injury (posterior displacement of bone fragments)
Vert body may look shortened AP
Compressed disc space, interspinous widening
Sagittal fracture through body as well as the
Anteroinferior corner
C5/6
Note, extension C2, widened disc space, still anteroinferior corner, stable in flexion, unstable in extension (ALL disrupted)
66
Atlanto-occipital interval (condyles)
<4mm (xray) 2mm (CT)
67
Wackenheim line
Down clivus, usually intersects Dens
68
Powers ratio
Basion to posterior arch / opthision to anterior arch
| Abnormal is >1
69
GCT
2nd most common primary sacral tumour after chordoma
Heterogeneous due to haemorrhage, necrosis, fibrosis
Locally aggressive
Most around knee - distal femur, then other long bones, but also posterior elements
Can cross SI joints
Donut sign NM
Female prediliction, but malignant transformation more common in men
Closed growth plate - 20s,30x
```
Abut growth plate
Well defined non-sclerotic margin
Eccentric
Thinned cortex
10-30% periosteal reaction
May have soft tissue mass
Cortex may be expanded, thinned, or deficienc
```
Well circumscribed expansile
70
Sacral lesion
```
SPACE MONGREL
Sarcoma (osteo, chondro)/SC teratoma
Plasmacytoma
ABC
Chordoma
Ependymoma
Mets
Osteomyelitis
Neuroblastoma
GCT
Rectal
Ewings
Lymhoma / leukaemia
```
71
Superscan
```
Mets - prostate, breast, TCC, lymphoma
HPT
Myelofibrosis
Mastocytosis
Wide spread Pagets
```
72
Eosinophilic granuloma
Intra-osseous High T2, low T1, may enhance
Calvaria in 50%, long bones next (note ribs most common place in adults)
Monostotic in 50-75%
Long bones: diaphysis 58%, metaphysis 28%
Often have spontaneous resolution, 6-18 months
30% bone scan negative
Male 2:1 female
Skeletal system the most commonly involved in LCH
Tends to be older children, asymptomatic, incidental
Floating teeth
Bevelled edge skull lesion
Respects growth plates
Periosteal reaction and endosteal scalloping
73
Sclerosing osteomyelitis of Garre
Chronic osteomyelitis, typically of mandible following caries.
Low grade non-necrotic non-purulent infection
74
Bone age
Utilises sex, size and shape of epiphysis, width of physis
75
Blount disease
Localised growth disturbance, proximal medial tibial epiphysis
AVN
Results in tibia vara
Can be unilateral or asymmetric but can be bilateral
Infantil type 80% bilateral. Later forms less common.
RF: obesity, early walking, black.
76
Bone echinococcus
Expansile, lytic lesions
(hydatid)
Uni or multilocular. Thinned cortex. Coarse trabeculae.
Vertebrae, paravertebral, pelvis, femur and lower limb soft tissues, tibia
Can affect both sides of a joint
77
Neonatal rubella
Celery stalk metaphyses
Metaphyseal, longitudinally aligned linear bands of sclerosis
Also seen in syphilis, CMV, osteopathia strata
78
Erlenmeyer flask deformity
```
CHONG
Craniometaphyseal dysplasia
Haemoglobinopathy - thalassaemia, sickle cell
Osteopetrosis
Neiman Pick (lysosome storage)
Gaucher (lysosome storage)
```
Also Achondroplasia, hypophosphatasia
Undertubulation
79
Clinodactyly
Downs
Turners
Klinefelters
Trisomy 18
80
Skull lesion
```
EG
Epidermoid
Myeloma
Mets
Infection
```
81
Peligrini Steida lesion.
Calcification adjacent to MCL at the femur. Post-traumatic.
82
Osteochondroma
>1.5cm cartilage cap suspect chondrosrcoma
| Also pain or growth after skeletal maturity
83
Rib notching
Regresses following succesful repair of coartcation in children
Can be seen as a normal variant in older people
84
Hill Sachs
Posterolateral fracture
| Best seen on AP internal rotation
85
Dashboard injury
PCL tear
Anterior force to tibia in flexed knee
Anterior tibia +/- posterior patellar bruising
86
Pivot shift injury
ACL tear
Posterolateral tibia, and mid lateral femoral condyle
Valgus stress to flexed externally rotated knee
87
Clip injury
Valgus stress to flexed knee
MCL
Bone bruising of lateral femoral condyle and lateral tibial plateau, and may have medial femoral bruising from avulsion
88
Hyperextension injury
Kissing condyles
| ACL, PCL, meniscal
89
Ligaments of wrisberg and humphry
Anterior (humphrey) and posterior (wrisberg) meniscofemoral ligaments
20-30% have both
90
PVNS
Usually monoarticular, knee - 70%. Painful
Can look histologically like aggresive neoplasm - rhabdomyosarc, synovial sarc
Extra articular disease (GCT of tendon sheath) has female predominance
Doesn't calcify
Mass like synovial proliferation with lobulated margin
Predominantly low signal, haemosiderin
May have areas of high T2 from oedema, effusion
15% recurrence after synovectomy
Diffuse form most common intra-articular
Localised more common extra
GRE helpful
2nd to 5th decade, no gender prediliction
91
Osteomyelitis plain radiograph
Sequestrum - detached necrotic cortical bone, develops after 30 days
Involucrum - periosteum forming around the infection, develops after 20 days
In infants, osteomyelitis may extend into epiphysis (typically)
92
Pagets
Paramyxovirus postulated
| Starts subchondral and extends into diaphysis. Rarely diaphysis only.
93
Synovial sarcoma
Knee most common
Lower limb 60-70%
Slight male predominance
40-70% mets - lung 80%, bones 15%, lymph nodes 10%
94
Liposarcoma
2nd most common soft tissue sarcoma after MFH
Adults 40-60
Rare in children
Extremities 75%, most commonly lower limb 45%. Less commonly groin, retroperitoneum.
```
Well differentiated most common
Myxoid type 2nd most common - low T1 with some high T1 foci
Round cell / de-differentiated
Pleomorphic
Mixed
```
95
Posterolateral corner injury
Biceps tendon, popliteus tendon and extras, LCL.
| Extras: arcuate, fibulopopliteal, fibulofabellar
96
Meniscal tear
2 slices
Extends to articular surface
Abnormal meniscal morphology if no prior surgery
Medial 45%
Lateral 22%
Both in 33%
(think medial more common in children too)
97
Brodies abscess
Intraosseous abscess in subacute pyogenic osteomyelitis
Penumbra sign of High T1 rim around the abscess, useful descriminator.
Tortuous channel extending to the growth plate is pathognomonic
Oval orientated in long axis of bone
Dense rim of sclerosis fades impercetibly into the surrounding bone
Usually metaphyseal. Rarely crosses growth plate into metaphysis
98
Osteochondritis dissecans
Knee, talus, capitellum (and glenoid)
Male 2:1 female
Knee classically medial femoral condyle, lateral surface, (lateral condyle only 10-15%) bilateral in 25%
Medial talus classical
(Both talus and femur are classicaly medial)
99
ABC
Mostly children and adolescents - 80% <20
1/3 secondary
GCRT in jaw is a variant
Metaphysis, by an unfused growth plate (much like UBC)
Eccentric (unlike UBC which is central)
Expansile with thin sclerotic margin, well defined
50-60% long bones, 20-30% spine and sacrum, esp posterior elements
Contiguous vertebrae in 25%
Spontaneous regression may occur but is not the normal history
Poorly vascular on angiography
No gender prediliction
Younger than GCTs
Doughnut sign of peripherally increased uptake on NM (also seen in UBC, GCT)
100
Fibrous dysplasia
Ribs most common monoostotic
Polyostotic commonly unimelic (McCune Albright is unilateral)
Intramedullary, expansile, endosteal scalloping)
May cause limb length discrepency, looser zones, sheperds crook and bow leg deformities
Can have ray pattern
Often metadiaphyseal
Sarcomatous degeneration not very common (less than pagets for example)
Well defined border, but not sclerotic rind
Usually children and young adults
Increased bone scan uptake
Usually do not progress beyond puberty
In skull, hemicranial, and inner table spared
Polyostotic 20-30%, with spin involvement in about 15% of these
Reactivation with pregnancy
Extracranial lesions rare in Leontiasis (/craniofacial - note cranium = everything but mandible)
101
Pseudoarthosis
OI
NF1
Ehlers Danlos
Fibrous dysplasia
(not Marfans)
102
Non-ossifying fibroma
```
>3cm (if less then fibrous cortical defect)
8-20
High incidence - 40%
M 2:1 F
Most asymptomatic
```
Associations: NF1, fibrous dysplasia, Jaffe Campanacci syndrome
Do not touch lesion
Most spontaneously resolve
Can bone graft
Long bone shafts - eccentrically in metaphysis, migrate away with age
Can cause hypophosphataemic vitamin D resistant rickets
103
Chondroblastoma
```
Matrix mineralisation in 60%
Eccentrically in epiphysis - humerus most common (according to radiopaedia, whereas danert says 2/3 about knee, and lumps greater trochanter and proximal femur together - path notes say 3x more likely to be greater trochanter than head of femur), with 70% in humerus, femur, tibia. 10% in hands and feet.
May be found in apophyses
Male prediliction
Lots of oedema, chicken wire calc.
```
Periosteal reaction away from the joint lesion in 30-50%
104
Enchondroma
```
Solitary in 75%
Expanded
Endosteal scalloping
Proximal phalanges then metacarpals
Osteochondromas more common (enchondroma are 2nd most common cartilage tumour)
```
Centrally within medullary cavity
Usually metaphyseal, although frequently also in diaphysis. Epiphysis rare - consider chondrosarcoma
105
Hypervitaminosis A
Causes diffuse periostitis
Also hepatosplenomegaly
Tendinous and ligamentous calcification
One cause is iatrogenic, cancer treatment e.g. neuroblastoma
Caffeys disease a differential (infantile cortical hyperostosis)
106
Mandibular periostitis
```
LCH
Tumour
Radiation necrosis
Osteomyelitis
Sclerosing osteomyelitis of Garre
Actinomycosis, syphilis, TB, pyogenic
Reactive to other nearby infection
Caffeys
Hypervitaminosis A
```
107
Ewing sarcoma
```
Male prediliction 1.5:1
Femur most common
Moth eaten permeative
Metaphyseal or diaphyseal - mid dia 33%, metadia 45%
Onion skin periostitis
Children and adolescents, 10-20
```
No osteoid matrix
Flat bones and may appear sclerotic in 30%
108
Symmetrical periosteal reaction
```
Venous insufficiency
HPOA
Fluorosis
Thyroid acropachy
Pachydermoperiostosis (primary hypertrophic osteoarthropathy)
```
Children:
Congenital syphilis
JIA
Caffeys disease (most common cause before 6 months - infantile cortical hyperostosis)
109
Generalised periosteal reaction
```
Vascular
Syphilis congenital
Fluorosis
Gauchers
HPOA
Pachydermoperiostosis
Hypervitaminosis A
Caffeys
Thyroid acropachy
Tuberous sclerosis
```
110
Platybasia
143 degrees... Sams numbers to remember still to finish
111
Arthritis, periosteal reaction
JRA, psoriatic, reiters, septic (may see in hands in ank spond, and in IBD can have ank spond or HPOA)
112
Kummel disease
Vertebral body osteonecrosis (note navicular is kohlers, lunate is keinboch)
Intervertebral vacuum cleft may be seen
Delayed collapse usually due to ischaemia / non-union of anterior wedge
Thoracolumbar junction most common
113
Medial clear space
Increased if deltoid ligament injured
| >4mm is increased
114
Maissoneuve mechanism
External rotation with foot in pronation
115
Spondylolysis
L5 most common, with anterolisthesis of L5 on S1
116
Ulnar impaction syndrome
Ulnar head impacts on ulnar sided carpus, with injury to TFCC
Associated with positive ulnar variance (i.e. long ulna) and dorsal radial tilt, which may be due to a previous fracture
(note Keinbochs is associated with negative ulnar variance)
117
Haemophilia
```
Large epiphyses (associated gracile diaphyses) secondary to hyperaeamia
Periarticular osteopaenia
Synovial density from iron deposition
Can cause chondrocalcinosis
Widened intercondylar notch (overgrowth of femoral condyles / large epiphyses)
Large degenerative cysts
Square patella
Knee then elbow then ankle
```
Haemosiderin on MR
And enhancing synovium - synovitis
Cartilage loss and erosions
118
Psoriatic arthritis
Diffuse soft tissue swelling of a digit (sausage digit - characteristic)
Assymetric
Bone proliferation
Periostitis
Acro-osteolysis
Assymetric SI joint involvement,
“Floating syndesmophytes” / parasyndesmophytes
Bony anklysis of interphalangeal joints
Ulnar deviation at MCP joints may be seen
Ivory phalanx
Can cause atlanto-axial subluxation
119
Syndesmophyte
Ank spond
Ochronosis
Fluorosis
120
Parasyndesmophyte
AKA floating syndesmophyte
| Dystrophic calcs in psoriatic and Reiters
121
Arthritis mutilans
```
Marked bony erosion with collapse of soft tissues
Psoriatic
RA
Reiters
JCA
Gouty arthritis
```
122
Chondrocalcinosis
```
HPT
Gout
Wilsons
Haemachromatosis
Ochronosis
Pseudogout / CPPD
Acromegaly
OA
Hypothyroid
Hypomagnesaemia
Hypophosphataemia
Haemophilia
Other arthritis
Diabetes
```
123
HPOA
Lung - cancer (in particular squamous), mesothelioma, abscess, bronchiectasis, AVMs
Heart - cyanotic heart disease
GI - IBD, coeliacs, PBC, whipples, gastric cancer, GI lymphoma, other cirrhosis, bile duct cancer, hepatic abscess
Also nasopharyngeal cancer, pancreatic cancer, CML
124
Stills disease
Systemic onset JRA
125
JIA
Current name in vogue
Stills is systemic onset
Most common chronic arthritis of childhood
F 2:1 M
Subtypes: oligoarticular (or less joints), polyarticular, systemic onset
Oligo tends to be larger joints than poly
Epiphyseal overgrowth, premature maturation and fusion
Wide intercondylar notch in knee
Periarticular osteopaenia, and periosteal reaction
Pericardial and pleural effusion if systemic onset
Metaphyseal lucencies
Acetabula protrusio
Ankylosis
Appearance can be similar to haemophilia
Sometimes RF positive
126
Lytic bone lesions on both sides of a joint
Synovial sarcoma / synovioma
Angioma
Chondroid lesion
(maybe hydatids also)
127
Sacroiliitis
IBD associated arthritis can also be seen in Whipple disease
Bilateral symmetric: IBD and Ankspond most common, but also RA, crystals, ochronosis, acromegaly, osteitis condensans ilii (sclerosis only to ilium)
Bilateral asymmetric: psoriatic, reiters, also JRA
Unilateral: Infection, OA, atypical bilateral process
Relapsing polychondritis and Behcets can affect
TB and brucellosis can cause unilateral.
SAPHO can affect.
128
Reflex sympathetic dystrophy
```
Painful swelling
Soft tissue atrophy
Subcortical erosions (juxta-articular and subchondal bone)
Metaphyseal lucent bands
Focal osteopaenia
Preservation of joint space
Subperiosteal bone resorption
```
129
1st CMC joint
Severe resorbtion seen in scleroderma
130
Ivory phalanx
Pathognomonic for psoriatic arthritis
131
Tuberculous dactylitis
```
Typically children more than adults
In children, consecutive bones may be involved
Proximal phalanx index, middle fingers, and metacarpals of middle, ring fingers typical
Diaphyseal expansile lesion
Periosteal reaction uncommon
Healing by sclerosis
Soft tissue swelling
Small sequestrum
Additional lesions appearing over time
```
Spina ventosa
132
Hip axial migration
Seen in inflammatory arthritides more than OA
133
Chronic liver disease
Risk factor for osteoporosis
134
Primary hyperparathyroidism
Female predominant 3x
Bone changes in 10-20%
May have psychosis
Occasionally secondary to parthyroid carcinoma (only 1-5%)
135
Acromegaly
Heel pad >25mm
136
Reverse segond
MCL avulsion tibia
| Associated with PCL tears and medial meniscal injury i.e. reverse of ACL segond
137
Shin splints / stress fracture
Shin splint - linear NM uptake
| Stress fracture - fusiform
138
PCL tear
Enlarged and thickened >7mm AP
| Or replaced by high T1 and T2
139
Periarticular calcification
```
Crystal arthropathy
Calcific tendonitis
Hyper and hypoPT
Scleroderma
Tuberculous arthritis
Hyper vitD
Sarcoid
Dermatomyositis and polymyositis
Ochronosis
Ehlers Danlos
Synovial sarc
```
Apparently shistosomiasis also
140
Atlantoaxial subluxation
Congenital, arthritis, and acquired
NF1, Marfans, OI, Downs (20%), Morquious (and Hurlers), spondyloepiphyseal dysplasia
SLE, RA (6%), Reiters, Psoriatic, ank spond
JRA (66%)
Trauma, infection e.g. Grisel from retropharyngeal absces
141
Floating teeth
Lamina dura destruction
Periodontal disease, LCH, HPT
Pagets
Infection and neoplasia
142
Pagets v FD skull
FD tends to be hemicranial, and spares inner table
Both can thicken cortex and have diploic widening
Cotton wool skull Pagets
143
Craniometaphyseal dysplasia
Dense skull base, facial bones, mandible
Obliterated sinuses
Undertubulated long bones (/Erlenmeyer Flasks)
AR
144
Cranial nerve palsies
Question about MSK causes
Pagets, FD, osteopetrosis and chordoma all recognised causes
Not MPS or cleidocranial dysostosis
145
Cretinism
Short stature, enlarged head, mental retardation
Stippled epiphyses (along with maternal warfarin, syndrome chondrodysplasia punctata)
Wide sutures with delayed closure - delayed maturation
Calvarial thickening
Wormian bones
Dense vertebral margins
Delayed dentition
Hypoplastic 5th
Hypertelorism
(no skeletal changes with adult onset hypothyroid)
(hypothyroid is on the list of causes of basal ganglia calcification)
146
Homocysteinuria
Eyes - ectopia lentis dislocated lens
CNS - siezures, dystonia, developmental delay
Skeletal - scoliosis, pectus excavatum, long limbs, osteoporosis, ligamentous laxity
Vascular - thromboembolism, premature cardiovascular disease causes most mortality
AR
147
Hyperphosphatasia
```
AKA juvenile pagets
AR
Cortical thickening, trabecular thickening, osteopaenia
Bowing
May have epiphyseal sparing
High serum ALP (rapid turnover of bone)
Virtually every bone affected
```
148
Hypophosphatasia
```
Condition resembling rickets
Decreased ALP production by osteoblasts
Variable clinical expression - perinatal benign, perinatal lethal, infantile, childhood, adult
Osteoporosis
Irregular metaphyses
Bowing
Craniosynostosis
```
149
Multiple lucencies around a joint replacement
Infection
| Particle disease / aggressive granulomatosis
150
Acro-osteolysis, extra causes
```
Psoriatic, reiters, juvenile chronic arthritis
Vasculitis e.g. Buergers (male non-smokers)
Asymbolia = insensitivity to pain
Ergot poisoning
Phenytoin (infants of epileptic mothers)
Epidermolysis bullosa
Pitaryasis rubra
Porphyria
Dermatomyositis
```
151
Ochronosis
=alkaptonuria
AR
Blue-black discolouration of ear cartilage and ocular tissue
Osteoporotic bones and disc calcifications - involves nucleus pulposis
Early OA, chondrocalcinosis
Syndesmophytes
Sacroillitis
152
Intervertebral disc calcification
```
Degerative
Traumatic
Ochronosis - nuc pulp as well as syndesmophytes
Ank spond
Transient in children
Pseudogout, haemochromatosis
JRA
Hypervitaminosis D
HPT
Amyloidosis
Acromegaly
Polio
```
153
MPS
Hurlers type 1, Morquio type 4
Morquiou 1:40000, Hurlers 1:100000
Hurlers - J-shaped Sella, shortening and widening of long bones, widening of ribs, heart disease, vertebral body beaking, prominent perivascular spaces, madelung deformity
Morquoiu may see multiple epiphyseal centres, flared iliac wings with increased angles, various others
154
Conditions resembling rickets
Hypophosphatasia
Biliary atresia
Metaphyseal chondrodysplasia (Type Shmidt)
Metabolic bone disease of prematurity
155
Vertebral body beaking
MPS (Morquiou middle third, all other causes including Hurlers lower third)
Achondroplasia
Cretinism
Down
156
TB arthritis
Typically mono-articular
Spine most common
Then hip, knee, SI joints, other large joints
157
Metacarpal index
Ratio of length to width, with normal around 9
| First introduced for diagnosis of Marfans (not used for bone age)
158
Hemihypertrophy
NF1
McCune Albright
Beckwith Weidemann
Klippel Trenaunay
Proteus
159
Wide intercodylar notch, knee
JRA, haemophilia, TB (unilateral)
160
Tibiotalar slant
Superolateral angulation of the plafond (i.e. medial plafond slopes downwards). Results in ankle valgus.
```
Haemophilia
JRA
Multiple epiphyseal dysplasia
Trauma, infection
Sickle cell
NF
Fibrous dysplasia
Multiple hereditary exostoses
```
161
Multiple epiphyseal dysplasia
Non rhizomelic dwarfism
Flattened, fragmented epiphyses
AD
162
Madelung deformity
```
Achondroplasia
Turners
Hurlers
Hereditary exostoses
Olliers
Nail patella
Leri Weill
```
163
Hepatic osteodystrophy
Bone disease in chronic liver disease
| Osteoporosis.
164
Pinna calc
```
Hyper and hypoPTH
Ochronosis
Gout and pseudogout
Adrenal insufficiency
Trauma
Relapsing polychondritis
Sarcoid
Diabetes
```
165
Cleidocranial dysostosis
.
166
Holt oram
.
167
Fanconi anaemia
.
168
Radial ray anomaly
.
169
Clavicle hypoplasia
.
170
Parsonage turner
Idiopathic acute brachial plexus neuritis
Bilateral in 1/3
Male predominant
Viral or immunological suspected
Neurogenic oedema in affected muscles, with more chronic changes having increased T1
Suprascapular nerve in 97%, only nerve involved in 50%
(supraspinatus and infraspinatus)
Subscap (teres major and subscap) and axillary nerves (deltoid and teres minor) sometimes affected
Self limiting, 90% recover in 3 years
Differential: quadrilateral space syndrome (teres minor and deltoid)
171
Quadrilateral space syndrome
Compression of axillary nerve and posterior circumflex humeral artery
Teres minor and deltoid denervation changes
Caused by muscle hypertrophy or fibrous bands
Medial: long head biceps
Lateral: humerus
Superior: teres minor inferior border
Inferior: teres major superior border
172
Brachial plexus
Emerges between anterior and middle scalenes
RTDCB roots trunks divisions cords branches
Rugby teams drink cold beer
173
Nail patella
.
174
Bone lymphoma
```
If metadiaphyseal lesions >30, solitary, with layered periosteal reaction, high suspicion for lymphoma
Peak 60-70
Femoral metadiaphysis most common, 25%
Soft tissue mass
Periosteal reaction 60%
Lytic destructive 70%
Sequestrum may be seen
May have mixed lysis and sclerosis with the rarer Hodgkin lymphoma
```
175
Sequestrum
```
EFILM
Eosinophilic granuloma
Fibrosarc
Infection
Lymphoma
Mets and MFH
```
176
Nail patella
```
Absent / hypoplastic nails
Absent / hypoplastic patellae
Posterior iliac horns (Fongs prongs)
Protruberant anterior iliac spines
Hypoplastic capitellum and radial head
Autosomal Dominant
```
177
Wide intercondylar notch
JRA
Haemophilia
TB (usually unilateral)
178
Most common in humerus
UBC and chondroblastoma (note chondroblasto more likely in greater trochanter than head of femure
179
Femoral lesions most common
```
Osteosarc
Ewings sarc
Fibrous cortical defect
GCT
Osteoid osteoma ("lower limb")
```
180
Excess callus formation
A feature of Cushings syndrome
181
J-shaped sella
```
MPS
Achondroplasia
NF
Optic chiasm glioma
Rarely a pituitary mass
```
182
Occipital condyle fracture
1 compression
2 basal skull extending to condyle
3 alar ligament avulsion - unstable
10% have associated C1/2 fracture
183
165-169, 173, 184
.
184
Small paranasal sinuses
Downs
Craniometaphyseal dysplasia
Osteopetrosis
185
Osteopetrosis
Infantile AR and Adult AD
Defective osteoclasts
Thick bones
Weak - fracture
Extramedullary haematopoiesis
Infantile few live past middle age, 70% dead by 6
Treat with bone marrow transplant
Causes radiolucent metaphyseal bands and sandwich vertebrae
Cranial nerve abnormalities - deafness, blindness
Hydrocephalus
Poor dentition may lead to osteomyelitis
Paranasal sinus obliteration
Obliterated diploic space
End-plates of sandwich vertebrae are usually denser than those of rugger jersey spine, and do not extend to the anterior vertebral bodies
186
Intra-osseous lipoma
Long bones of lowed limb most commonly -50%
Calcaneus is the most common tarsal -15%
Central nidus of calcification pathognomonic
187
Septic arthritis
```
Staph most common
Gonnococcus
IV drug users may have unusual oranisms
Discitis in spine, IVDU, strep viridans
Other IVDU bugs - pseudomonas. klebsiella, serratia
```
188
HADD / calcific tendonitis (location)
Supra most common, then infra. (or supra and biceps depending on source)
189
Knee cruciates
AL, PM
| ACL has AMB and PLB
