MSK Flashcards
(201 cards)
1
Q
Thalassaemia features
A
> bone infarcts, marrow hyperplasia, infection. marrow expansion is much more prominent
* widening + squaring of phalanges and metacarpals.
* skull - hair-on-end striations more common than sickle cell
* obliterate paranasal sinuses
RODENT FACIES
* long bones - Erlenmeyer flask deformity
2
Q
Pseduosubluxation features
A
Anterior spinous process of C2 within 2mm of C1-C3
3
Q
SLAC / SNAC wrist
A
SLAC Wrist - injury (or degeneration via CPPD) S-L ligament.
> Radioscaphoid joint is first to develop degenerative changes
>Becomes a DISI
SNAC Wrist = SMACK = scaphoid fracture. Scaphoid tilts into flexion, capitate migrates proximally
Scaphoid fracture assoc= perilunate dislocation
4
Q
DISI / VISI
A
VISI- ulnar sided injury, triquetrolunate ligament damage, volar lunate angulation, scapholunate angle <60, increased capitolunate tear (>30)
DISI- scapholunate tear
raDial sided injury, capitate migrates PROXIMALLY, increased capitolunate (>30) + scapholunate angles (>60) , lunate tiled dorsally
*D = DEUX- x2 angles increased
> SLAC wrist becomes DISI
5
Q
Normal wrist angles
A
scapholunate 30-60
capitolunate <20
scapholunate dissocation >60 degrees, >3mm gap
6
Q
Bone lesions
A
- Osteoid osteoma: diaphysis long bones + posterior elements spine <2cm
RX= RFA. GARDNER SYNDROME - Osteoblastoma: >2cm, lytic lesion with mineralisation, *2ry ABC
- Osteosarcoma: metaphysis of distal femur/ proximal tibia, occurs post Pagets/ radiation
- Osteochondromatosis: similar sized loose bodies, knee, can occur both sides of joint, RING +ARC CHONDROID CALC
- Enchondroma: chondroid matrix, high T2, lucent lesions hands *progressive decarease in minerlisation= worrying
-Osteochondroma: points away from metaphysis, cartilage cap >2cm- think chondrosarc
- Chondroblastoma- eccentric, epiphysis, LOW T2 SIGNAL, lmee/ proximal humerus, kids, also seen in epiphyseal equivalent
- Chondromyxoid fibroma: eccentric, metaphysis of knee, HIGH T2
- Chondrosarc >osteochondromas, pagets, enchondromas, expansile medullary lesion, endosteal scalloping
- FCD- metaphysis, scleortic border, regress
-Bone cyst- cemtrally placed, diaphysis
-GCT: NON SCLEROTIC BORDER, abuts articular surface, KIDS, can have pulmonary mets
-ABC: assoc with GCT, <30yo
7
Q
Osteosarcoma subtypes
A
- Conventional = commonest
- Parosteal= posterior distal femur, lucent line separates it from cortex, outer periosteum, “caulifower like”
- Periosteal: inner periosteum, cortical thickening + aggressive periosteal reaction. DIAPHYSEAL. usually no marrow extensionclassic location = medial distal femur
- telangectactic: looks like ABC. High T1 (from MtHb). Differentiated from ABC GCT by tumor nodularity / enhancement.
Mets= lung, bone, nodes
ADEOLSCENTS + ELDERLY >70 (Pagets)
8
Q
Lucent bone mets
A
- Lung (most common purely lytic).
- Breast (lytic or blastic).
- Thyroid.
- Kidney.
- Stomach, colon (lytic or blastic).
9
Q
Sclerotic bone mets
A
- Breast (lytic or blastic).
- Prostate, seminoma.
- Transitional cell carcinoma. * Mucinous tumors.
- Carcinoid.
10
Q
Jaffe-Campanacci Syndrome:
A
multiple NOFs, cafe-au-lait spots, mental retardation, hypogonadism, and cardiac malformations.
11
Q
Clear cell chondrosarcoma
A
epiphysis
12
Q
ACL rupture
A
*pivot injury
- ANTERIOR translocation of TIBIA
- buckling of PCL
- Segond fracture (LATERAL tib plateau)> associated with IT band
- O’Donoghues triad: ACL + MCL + medial meniscus tear
- LATERAL FEM CONDYLE BANGS INTO POSTEROLATERAL TIBIA
- deep intracondylar notch sign- lateral femoral condyle
> mucoid degeneration can mimic this- straited/ celery stalk appearance
Repair- Cyclops lesions, Hoffas, low signal >16 weeks
Graft tear= FLAT ANGLE, grossly high T2, fiber discontinuity, uncovering of posterior horn of lateral meniscus, anterior tibial translation
13
Q
Magic Angle
A
Short TE sequences (Tl, PD, GRE). It goes away on T2
REDUCED AT HIGHER FIELD STRENGTH
PCL and Patellar tendon may have foci of intermediate signal intensity SAG IMAGES
CAN MIMIC A SUPRASPINATUS TEAR
14
Q
Posterior lateral corner
A
LCL, the IT band biceps femoris + popliteus tendon. *edema in fibular head +/- arcuate ligament (may be absent)
VARUS FORCE
15
Q
PCL injury
A
*hyperextension injury
- increased laxity
- thi nk popliteal artery occlusion
- REVERSE SEGOND: medial tibial plateau and medial meniscus injury
16
Q
Discoid meniscus
A
LATERAL meniscus, prone to tear
>3 bow ties
17
Q
Bucket handle tear
A
LONGITUDINAL tear of MEDIAL MENISCUS, flips medially to lie anterior to PCL. DOUBLE PCL
double deLta sign> displaced fragment flips anteriorly
= likely Lateral meniscal tear (or medial meniscus tear + torn ACL).
Double PCL sign = medial meniscus tear (with intact ACL).
18
Q
Meniscal flounce
A
- ruffled appearance, can mimic a tear
19
Q
CAM/ PINCER
A
- CAM: osseous bump of femur, young athletic males, elevated alhpa abgle, hip alpa angle >55
assoc: SUFE RX: FEMOROPLASTY - PINCER: acetabular overgrowth, cross over sign, middle aged females, acetabulum is malformed - causing the posterior lip to “Cross over” the anterior lip, *coxa profuna + protrusio, Assoc: os acetabuli RX: SURGICAL TRIMMING
20
Q
LABRAL TEAR HIP
A
Anterior superior labral tear
21
Q
Arcuate sign
A
- avulsion of proximal fibula
- assoc: cruciate ligament tears
22
Q
Perilunate vs lunate
A
- PERILIUNATE: bones around the lunate moves eg. capitate. assoc: scaphoid fractures
-LUNATE : lunate moves, others stay, Dorsal radiolunate ligament injury, Assoc: triquetrolunate interosseous ligament disruptio, Triquetral Fracture
- MID CARPAL DISLOCATION: both capitate and lunate lose alignment,
23
Q
Galeazzi vs Monteggia
A
GaLeazzi: distal third radius fracture + UNLAR DISLOCATION DISTALLY
MontEggia: ulnar fracture +radial dislocation at the Elbow.
24
Q
DISH
A
- Ossification of the ALL > 4 VBS, left lateral aspect spared- thoracic aorta
CF Ank spond = syndesmophytes= calc of the ligaments - thoracic spine
- normal IV discs
- no SI’s
- Diffuse Paravertebral Ossifications
Assoc: ossification of PLL
*heel + elbow spurs + pelvic enthesophytes, patellar ligament ossification
*stylohyoid ossification
25
Psoriatic arthritis
- PARASYNDESMOPHYTES- paravertebral dystrophic soft tissue calc, bone marrow oedema affecting entire VB
mineralization is preserved. Sacroiliitis=usually asymmetric.
26
Boutonniere's vs swan neck
B: DIP flexion + PIP extension
S: DIP extension + PIP flexion
Mallet: flexion deformity of DIP- hyperextension injury
27
Maissoneuve
fracture of proximal fibula + distal tibiofibular syndesmosis disruption
28
Scleroderma
- acroosteolysis
- periarticular and soft tissue calc
- joint contractures
-sclerodactyly
Resorption of the terminal phalanges (acro-osteolysis) > pencilling or sharpening of terminal phalynx.
●● Subcutaneous/joint calcifications in 25%.
●● Severe resorption of the first CMCJ with radial subluxation of the
first metacarpal bone = pathognomonic.
29
Sinus tarsi syndrome
- between lateral talus and calcaneus
- loss of fat signal + synovial thickening
+/- tears of talocalcaneal ligaments, inferior extensor retinaculum
30
Hemochromatosis
- osteoporosis
- joint space narrowing
- hook like osteophytes affecting ALL MC heads
- chondrocalcinosis
2nd and 3rd MCP joint involvement (‘squared’ metacarpal heads) ▸ joint space narrowing ▸ ‘hook-like’ osteophytes radial aspects of MC heads- MORE COMMONLY AFFECTS 2-5TH THAN JUST2/3rd ▸ numerous subchondral cysts
31
CPPD
*chondrocalcinosis
- affects TFCC> SLAC wrist
- patelliofemoral joint first affected in knee
- hook like osteophytes 2/3rd M/Cs
32
Acromegaly
- Beak like ostephytes MC heads
- Terminal tufts - spade like
- Initially widened joint spaces then narrowed
Enlarged sella
thickened skull
Enlarged frontal sinuses
33
Ulnar nerve compression
Hook of hamate fracture- Guyons canal
OA of pisotriquetral joint
34
Transient patellar dislocation
-contusions lateral femoral condyle + medial patella +/- OCDs +/- disruption of medial retinaculum
-effusion/ lateralisation of patella
35
Blounts disease
-osteochondrosis of the MEDIAL TIBIAL CONDYLE > tibia varus (bowing) and internal rotation
36
Myositis ossificans
- also has string sign CF osteosarcoma
37
Ewings
2nd Most Common Primary Bone Tumor in Kids
DIAPHYSIS of Femur and FLAT BONES (OSTEOSARCOMA DISTAL TIBIA METAPHYSIS/ AROUND THE KNEE)
+ also affects axial skeleton
Soft Tissue Components =Common
Calc rare
Mets to lungs + other bone (spine)
POSITIVE ON ALL 3 PHASES BONE SCAN
38
Mazabrauds
FD + soft tissue myxoma
39
McCune Albright
Polyostotis FD+ autonomous endocrine hyperfunction + café-au-lait macules.
40
Malgaigne
UNSTABLE FRACTURE
disruption of ipsilateral superior and inferior pubic rami + SIJ
Vertical shearing force
Can cause urethral disruption + diastasis
41
Bladder rupture
EXTRAPERITONEAL
- More common
- Assoc: pelvic fractures
-Molar tooth sign =inverted U appearance of contrast in extraperitoneal space of Retzius
*POSTERIOR URETHRAL INJURY ASSOCIATED WITH PELVIC FRAC
*blood at meaturs- need retrograde urethrogram first
INTRAPERITONEAL
-direct blunt force
- intraperitoneal contrast interdigitating between bowel loops + paracolic gutters
- surgical management
URETHRAL TRAUMA
Type III= most common, disruption of urogenital diaphragm + rupture of the bulbomembranous urethra >contrast into pelvis and out into perineum
42
URETHRAL INJURY
Anterior- PENILE + BULBAR
straddle injury> most commonly affects BULBAR portion
- need retrograde urethrogram
Posterior- MEMBRANOUS + PROSTATIC, pelvic fracture- needs voiding urethrogram
*gonoccocal stricture= distal bulbous
43
Erosive arthropathy
PIP and DIP joint involvement ▸ joint ankylosis ▸ ‘gull-wing’ deformities (central erosions and marginal osteophytes)
44
RA
Symmetrical arthritis ▸ MCP and PIP joint involvement ▸ periarticular (early) and diffuse (late) osteopenia ▸ marginal
erosions ▸ subluxation (swan neck and boutonnière deformities) ▸ periostitis is uncommon
Joint space narrowing ▸ marginal erosions ▸ synovial cysts ▸ protrusio acetabulae
Atlantoaxial subluxation
45
JIA
Joint ankylosis ▸ florid periosteal reaction ▸ osteopenia
Abnormalities of growth and maturation ▸ epiphyseal overgrowth / premature closure of the physis ▸ widened intercondylar notch
Apophyseal joint fusion ▸ atlantoaxial subluxation
KNEE= COMMONEST SITE MONO INVOLVEMENT, WIDENED INTERCONDYLAR NOTCH
SERO -VE
46
Psoriatic arthropathy
‘Sausage’ digit ▸ DIP joint involvement ▸ terminal tuft erosion ▸ pencil-in-cup deformity ▸ joint ankylosis ▸ arthritis mutilans ▸ fluffy periosteal reaction ▸ no osteopenia
Feet: affects MTP + IP great toe, calcaneal spur with peristeal reaction
Asymmetric sacroiliitis
Spine -Coarse syndesmophytes
*mineralization is preserved.*
IVORY PHALANX
47
Reiters
Looks similar to psoriatic arthritis but LOWER LIMB
Seronegative, young men
assymetrical SIJs
Hallux involvement ▸ periosteal reaction ▸ calcaneal erosions ▸ foot) osteopenia not prominent
Coarse syndesmophytes
Asymmetric or unilateral sacroiliitis
48
Dematomyositis
Soft tissue calcification
DIP joint erosions
49
Haemophilia
Epiphyseal overgrowth ▸ juxta-articular osteopenia ▸ erosion and cartilage destruction ▸ widened intercondylar and trochlear notches ▸ squared patella
50
Ank Spondylitis
Bilateral symmetrical sacroiliitis ▸ ankylosis
Anterior vertebral body squaring / sclerosis▸ syndesmophytes ▸ paravertebral ossification ▸ bamboo spine
‘Whiskering’ iliac crests and ischial tuberosities
Can have ALL ossification
51
Thalassaemia
-Hand- widening and squaring of phalanges and metacarpals.
Skull, hair-on-end striations
Face- obliterate the paranasal sinuses - rodent-like facies *SICKLE CELL WILL NOT OBLITERATE SINUSES*
* Erlenmeyer flask deformity.
52
Adhesive capsulitis
- thickened corachohumeral ligament + capsule
- smaller axillary recess
- fat obliterated between coracoid + coracohumeral ligament
lymphatic filling of contrast
- enhancement of inferior GLENOHUMERAL LIGAMENT
53
Ulnar impaction syndrome
Positive ulnar variance
lunate involved- cystic changes, TFCC tears
inferior glenohumeral ligament >4 mm)
54
Complete rotator cuff tear arthrogram
Fluid injected into glenohumeral joint that extends into subacromial/ subdeltoid bursa
55
Rugger jersey spine
- renal osteodystrophy
- osteopetrosis
56
Shoulder labrum variants
Sublabral foramen-anterosuperior segment not attached to glenoid
* A Buford complex - middle glenohumeral ligament is seen in combination with an absent anterosuperior labrum.
* Sublabral recess or foramen = unattached portion of anterosuperior labrum at the 12 to 3 o’clock position.
57
Shoulder disloction lesions
- Hill Sachs: posterolateral humeral head
- Bankart: anteroinferior glenoid *Assoc: GLOM, scapular perisoteum stripped
- Reverse Hill Sachs (posterior dislocation): anteromedial humeral head
- Inferior dislocation: greater tuberosity fracture, roatotor cuff tear, risk of damage to axillary nerve
58
C spine measurements
Atlantoaxial distance
■ Adults: <3 mm
■ Children: <5 mm
Soft tissues
■ Adults: <5 mm (C3 -C4)
▸ <22 mm C5-7 Retrotracheal space
■ Children: < 2/ 3 of width of C2 body
(at the level of C3 and C4 )▸
<14 mm (at the level of C6)
59
Fracture patterns
>Flexion =anterior wedged fracture.
>Extension = small triangular fragment separated from anterior inferior margin
>Distraction = horizontal fractures in posterior element, no wedging of the vertebral body.
>Flexion-distraction =horizontal fracture of posterior elements + anterior wedging
> Axial compression = anterior wedging + retropulsion of the posterior superior margin of vertebral body
>Shearing = fracture–dislocations > anterior displacement of the vertebra above the level of dislocation carrying + triangular avulsed fragment from the anterior superior margin of vertebral below. Fractures of the laminae and superior facets are commonly encountered.
>Rotational forces are combined with shearing to produce an anterior lateral dislocation of the spine.
BILATERAL FACET JOINT DISLOCATION
- unstable, VB moves anteriorly
**unstable = acute segmental kyphosis greater than 11 degrees, acute anterolisthesis greater than 3-4 mm
60
Unstable fractures
Vertebral Overriding > 3mm
Angulation > 11 Degrees
Flexion Tear Drop
Bilateral Facet Dislocation
Odontoid Fracture Type 2 and 3
x2 Thoracolumbar Columns
Three Thoracolumbar Columns (Chance Fracture, Etc...)
Jefferson Fracture
Hangman Fracture
Atlanto-Occipital and Atlanto-Axial Dislocations
61
Pelvic fracture
STABLE
– Straddle injury: fractures of ischial and pubic rami (often bilateral) with superior displacement of medial fragments
UNSTABLE
■ AP compression injury- head on collision
Type 1 symphyseal diastasis (<2.5 cm)
and vertical pubic rami fractures
Type 2 injury (‘open-book’ fracture): progressive widening of symphysis (>2.5 cm), or disruption of the sacroiliac, sacrotuberous and anterior sacroiliac ligaments ▸ intact posterior sacroiliac ligaments
Type 3: + posterior SI disruption
Lateral compression fracture. COMMONEST
SIJ + ipsilateral superior + inferior puic rami
Vertical shear injury
– Unilateral impact (fall from a height) ▸ vertical pubic rami fractures with superior displacement
– Malgaigne’s complex: a fracture of the medial ilium or sacrum + fractures of the superior and inferior rami on the ipsilateral side ▸ superior displacement of the affected hemipelvis
62
SL ligament tear
>3mm
- dorsal band gives most stability
63
Triplanar fracture
>Salter-Harris 4,
vertical fracture through epiphysis, horizontal component the physis, + oblique through metaphysis.
64
Tillaux fracture
- Salter-Harris 3
> ANTEROLATERAL aspect of distal tibial epiphysis.
**does not have oblique fracture through metaphysis
65
Distal radial fractures
Barton- intra-articular with dorsal angulation
Smiths- distal radius, VOLAR angulation
Reverse Barton- VOLAR ANGULATION
Hutchinson- intra articular radial styloid, scapholunate dissociation and perilunate dislocation.
66
Thumb fractures
- Bennett: intra articular base of thuumb, attach= abductor pollicis longus
- Rolando- comminuted Bennets
- Gamekeepers- base of proximal phalanx- UCL attaches *Stener lesion. MRI- yo yo
67
Looser zones
medial aspect of femoral neck ▸ pubic rami ▸ lateral border of scapula and ribs
Bone scans more sensitive than xr
68
Ulnar impingement
SHORTENED ULNA- compression of distal radioulna joint > early OA
69
Hyperparathyroidism
PLAIN FILM
● Osteopenia
● Chrondrocalcinosis.
● Soft tissue calcification
● Vertebral osteosclerosis - ‘rugger jersey’ spine — characteristic of secondary hyperparathyroidism/ renal osteodystrophy
● Bone softening: basilar invagination, vertebral collapse.
● Brown tumours - primary hyperparathyroidism
● Subperiosteal erosion -radial aspect of phalanges middle + index fingers
●Acroostelysis distal end of clavicles
*also acrolysis terminal phalanges
70
Shoulder Impingement
Primary external causes *abnormal coracoacromial arch
1. Hooked acromion
2. Subacromial osteophyte formation / thickening of coracoacromial ligament- impinge on SUPRAS
3. Subcoracoid impingement: Impinges SUBS
Internal *normal arch
* “Multidirectional Glenohumeral Instability” - micro-subluxation of humeral head in glenoid= repeated micro-trauma typically seen in generalized joint laxity
* Posterior Superior: posterior superior rotator cuff (junction of supra and infra tendons) comes into contact with the posterior superior glenoid, damages INFRAS. -athletes
* Anterior Superior: arm is in horizontal adduction and internal rotation. In this position, the undersurface of biceps + subscapularis tendon impinge against anterior superior glenoid rim.
71
Labral tears
- SLAP: superior area, runs anterior to posterior, assoc: biceps tendon injury, over head swimmers, if biceps involved then may need tendon surgery
- Sublabral recess= SLAP mimic. incomplete attachement of labrum at 12oclockFollows Contour of Glenoid SMOOTH Margin Located at Biceps Anchor < 3mm
- Sublabral formen- unattached labrum
- Burford- absent anterosuperior lbarum + thickened MIDDLE GLENOHUMERAL LIGAMENT
72
SLE
ANA +ve
- ulnar deviation at MCPS AND PIPS
- symmetrical involvement of ips- swan neck, boutonnieres
- hallux valgus
NO EROSION
73
AVNS
Kienbock: lunate, assoc: -ve ulnar varaince
Kohlers: navicular
Panners: capitellum
Severs: calcaneal apophysis
Freibergs: head of 2nd MT
74
Osteomalacia features
Ill-defined/ fuzzy trabeculae.
Ill-defined corticomedullary
junction, bowing, and “Looser Zones.”
Protrusio
75
Gout
needle shaped NEGATIVELY bifiringent
□ Earliest Sign = Joint Effusion
□ Spares the Joint Space (until late in the disease); Juxta- articular Erosions - away from the joint.
□ “Punched out lytic lesions”
□ “Overhanging Edges”
□ Soft tissue tophi
76
Osteomyelitis
- cold on tch99m SULFUR COLLOID scan
- indium labelled WCC- more specific +ve on Tc99 MDP scan on all 3 phases
gallium-67 scan can also increase specificity
77
SPINOGLENOID NOTCH
suprascapular notch >ATROPHY OF supraspinatus + infraspinatus.
spinoglenoid notch> ISOLATED atrophy of infraspinatus.
78
Quadrilateral space
axillary nerve and posterior humeral circumflex artery
> atrophy of teres minor
79
Charcot joint
Normal bone density, joint destruction, dislocation, debris
1. hypertrophic- destruction/ dislocation/ subluxation. no demineralisation
2. atrophic- shoulder- humeral head resorption, absence of sclerosis/ osteophytes, *think syringomyelia- MRI C spine
80
Amyloid shoulder
-soft bulky tissue nodules in shoulder, atrophic muscle, erosions- can look like RA
81
OCD
III- detached, non displaced fragment
IV- displaced fragment
82
flat foot
disruption of posterior tibialis tendon- swelling in MEDIAL malleolus
Posterior Tibial tendon rupture assoc: dysfunction of Spring ligament + thickened interosseous ligament
83
Accessory soleus
pre achilles fat pad mass
84
Plantaris rupture
“Achilles tendon ruptured but can still plantar flex.” it’s absent in 10% of the population. MRI = focal fluid collection between the soleus and medial head gastrocnemius Assoc: ACL tears.
> sharp pain, forced ankle dorsiflexion
85
Osteitis condensans illi
iliac side of SIJ=sclerosis which is typically bilateral, symmetrical, and triangular in shape
86
SONK
Medial femoral condyle +/- meniscal tear
stage I: normal
stage II: radiolucency in subchondral weight-bearing area
stage III: expanded lucent area surrounded by sclerosis, subchondral bone collapse
stage IV: osteophytes and osteosclerosis on affected condyle
87
Jaccouds arthropathy
- reducible hand subluxations
- hook like projections MC heads
Assoc: Rh fever
88
facial trauma
direct blow to face, flattened cheekbone
zygomatic arch fracture
89
Adamantinoma
well circumscribed, expansile, multiloculated, ANTERIOR TIBIAL DIAPHYSIS, thin sclerotic lesion, CORTICALLY BASED
90
Chondromyxoid fibroma
20-30yo
long bones, metaphysis> may extend to epiphysis, UPPER 1/3 TIBIA
PSEUDOTRABECULATION, well defined sclerotic lesion, PARALLEL TO BONE AXIS
91
Pilon fracture
comminuted fracture of distal tibia- axial loading, INTRAARTICULAR
92
Waggetaffe le fort
avulsion anterior distal fibula , insertion of ATFL
93
Haemangiopericytoma
- yin yang sign
strong enhancement + flow voids
94
Osteochondritis dissecans
LATERAL aspect medial condyle, adolscent boys
95
Maffucci syndrome
enchondromas + phleboliths
96
Lytic vs sclerotic bone mets
Lytic: Low T1, high T2
Sclerotic: LOW T1 +T2
97
Synovial haemangioma
soft tissue mass, linear areas of flow void, marked enhancement of mass
98
Hip AVN
Double line sign- linear of band of high + low T2 signal
T1: geographic subchondral lesion outlined by serpentine low signal rim
> initially decreased then increased radiotracer uptake
> ANTERIOR SUPERIOR REGION
*Gaucher= splenomegaly
*Sickle cell = small calcified spleen
CF STRESS FRACTURE= MEDIAL FEMORAL NECK
99
Basilar invagination
PF ROACH
Pagets, FD, RA/ Rickets, OI/ Osteomalacia, Achondroplasia, Chiari I+II, Cleidocranial dysostosis, Hyperparathyroidism
100
Dermatomyositis
- rash + inflammation of muscle/ skin + soft tissue calc
> musle: high stir, LOW SIGNAL IF CALC, cn undergo fatty atrophy
> lungs: NSIP or COP (perioheral subpleural consolidation/ nodulairty)
101
Sacroilitis
Symmetrical
Anklyosing spondylitis, IBD, RA
Asymmetrical
OA, Psoriasis/reactive arthritis ,Septic arthritis
102
Syndesmophytes (ANK SPOND) vs osteophytes
1. Syndesmophytes = vertical orientation
2. Osteophytes arise a few mm from the discovertebral junction
3. Osteophytes = triangular in shape
4. New bone formation in DISH arises from ALL and is prolific
103
OI
●● Multiple fractures
●● Exuberant callus.
●● Fractures - long bones, spine and apophyses.
●● Pseudarthroses - broken bone fails to fuse
●● Poor bone density.
●● Bone deformity—bending and thinning of the long bone diaphysis; e.g. ‘shepherd’s crook’ deformity
●● Deformity of the skull (e.g. platybasia, prominent occiput)
●● Wormian bones (>10)
●● Basilar invagination
●● Enlarged sinuses, abnormal teeth
●● Compression fractures multiple levels
●● Spondylolysis
●● Lumbar hyperlordosis
104
Morquio
●● Anterior central beak =specific.
●● Atlantoaxial subluxation due to odontoid hypoplasia.
●● Platyspondyly
●● Ovoid vertebral bodies.
●● Posterior VB scalloping and central beaking.
●● Widened intervertebral disc space.
●● Exaggeration of lumbar lordosis.
●● Fragmentation and flattening of the femoral heads
●● Flared iliac wings
●● Lateral sloping of the tibial plateaux
●● Genu valgus deformity
●● Bullet-shaped metacarpals
●● Short, wide tubular bones with metaphyseal irregularity
105
CAUSES OF ANTERIOR VERTEBRAL BODY BEAKING
Central = Morquio syndrome
Inferior = Hurler syndrome Achondroplasia Down syndrome
106
Mastocytosis
BARIUM FOLLOW-THROUGH
● Distorted, thickened nodular folds.
● Tiny nodular mucosal deposits- jej
● Dense sclerotic vertebrae
CT
● Hepatosplenomegaly
● Irregular small bowel fold thickening/ Ileal wall thickening
● Lymph node enlargement
107
Turners
-Shortened 3rd + 4th MC
- Madelung
- Carpal coalition
- narrowing of scapholunate angle
- Thinning of lateral calvicles
- Thinned ribs + notching
108
Idiopathic transient osteoporosis
- Osteopenia + subchondral bone loss
- extensive oedema + enhancement
●● Osteopenia femoral head seen 4–8 weeks after symptoms
●● Loss of subchondral cortex of the femoral head
●● No joint space narrowing / subchondral bone collapse.
●● Joint effusion.
Pregnant women + middle aged men
109
Pleomorphic undifferentiated sarcoma / MFH
LOW T1/T2
Elderly
Proximal/ central muscles- thigh
Hemorrhage/ foci of calc
peripheral nodular enhancement
110
Myxofibrosarcoma
HIGH T2
111
Nodular fascitis
SARCOMA MIMIC but benign
may be subcutaneous or deep
High 22, ENHANCE
112
Elastofibroma dorsi
subscapular region, deep to lat dorsi, more commonly right, middle-aged females
Crescenteric shape, alternating fatty/ fibrous bands
113
Desmoid fibromatosis
Anterior abdo wall
Aggressive but benign
low signal intensity
114
Synovial sarcoma
Lower extremity- knee, ankle, foot
Occurs not joint
>Triple sign- high, medium, and low signal in same mass
>*HIGH T2* - bowl of grapes > fluid -fluid levels in a mass
> Soft tissue component + calc
Bakers cyst mimic
115
Mazabraud syndrome
polyostitis FD + multiple MYXOMA
116
Marfan
●● Progressive scoliosis
●● Posterior VB scalloping
●● Spondylolisthesis
●● Arachnodactyly.
●● Pes planus.
●● Hallux valgus.
●● Acetabular protrusion
117
Brodie abscess
PARALLEL TO AXIS OF BONE
lucent line to epiphysis
metadiaphyseal
MRI
●● Double line effect-high signal granulation tissue surrounded by low signal intensity (sclerosis)
●● ‘Penumbra sign’—hyperintense rim on unenhanced axial T1
118
Giant cell tumour tendon sheath
● Solid hypoechoic mass + vascularity adjacent to FLEXOR TENDONS HANDS
MRI - low T1/2 due to haemosiderin
● Homogeneous enhancement
119
Red marrow reconversion
Red marrow- humeral heads and femoral heads =normal variant
Reconversion occurs in opposite order to conversion as follows:
Axial > appendicular skeleton,
METAPHYSIS> DIAPHYSIS > EPIPHYSIS
120
Posterior VB scalloping
●● Ehlers–Danlos syndrome
●● Neurofibromatosis
●● Marfan syndrome
●● Morquio syndrome
●● Acromegaly
●● Achondroplasia
●● Ankylosing spondylitis
●● Tumours in the canal (e.g. ependymoma, dermoid or lipoma)
121
Causes of anterior VB beaking
Central
Morquio syndrome
Inferior
Hurler syndrome
Achondroplasia Down syndrome
122
Patella baja
Ratio <0.8
Assoc: quadriceps dysfunction, polio, trauma, post ACL repair
123
Scheurmann
kyphosis > 35 degrees
affects 3-5 VB, THORACIC
124
Wormian bones
Pyknodysostosis
Osteogenesis Imperfecta
Rickets
Kinky Hair Syndrome
(Menke s /Fucked Copper Metabolism)
Cleidocranial Dysostosis
Hypothyroidism / Hypophosphatasia
One too many 21st chromosomes (Downs)
Primary Acro-osteolysis (Hajdu-Cheney)
125
Gauchers
Anaemia + splenomegaly
Modelling abnormalities (e.g. Erlenmeyer flask deformity), typically of the distal femur or proximal tibia
● Osteopenia.
● Osteonecrosis (AVN/bone infarct)—the combination of osteonecrosis + Erlenmeyer flask deformity is pathognomic.
126
Sickle cell disease
● Osteopenia and coarse trabeculae
● ‘Bone in bone’
● AVN
● Rib thinning with notching.
● AVN humeral heads
H SHAPED VERTEBRAE
● Skull—widening of the diploe with ‘hair on end’ striations
● Decreased uptake on bone scan
127
BROWN TUMOUR
Multiloculated
●● Expansile lytic lesion
●● Narrow zone of transition
Anywhere but commonly mandible
128
Epiphyseal lesions
ABC, Infection, Giant Cell, and Chondroblastoma.
Epiphyseal equivalants: Carpals, Patella, Greater Trochanter, Calcaneus
Malignant lesion= CLEAR CELL CHONDROSARCOMA
129
Simple bone cyst
Long axis parallel to long axis of bone
INTRAMEDULLARY
Likes proximal femir/ humeri
Metaphysis
NOF= metaphyseal, ECCENTRIC
130
Jefferson fracture
C1 STABLE
- AXIAL LOADING, lateral masses c1
131
Hangmans fracture
C2 UNSTABLE
- hyperextension + traction,
fractures through PARS OR PEDICLES, separates posterior elements from VBs
C2 displaces anteriorly to C3-
>3 m= likely unstable
Disrupted spinolaminar line
132
Odontoid Peg fracture
- unstable if through base or into VB
133
C2 Extension fracture
Hyperextension
Can be unstable
Teardrop from anteroinferior VB
Disruption of ALL
134
Flexion teardrop fracture
- Hyperflexion + axial compression
- Anterorinferior teardrop fracture + posterior displacement of that VB *ANTERIOR CORD SYNDROME- loss of pain + temperature- affects pyramidal + anterior spinothalamic tracts
* UNSTABLE
135
Chance fracture
Seatbelt injury. all 3 columns. UNSTABLE
Horizontal fracture through the VB + spinous processes
136
Burst fracture
- Thoracolumbar junction (also lower C spine)
- Disruption of posterior cortex
- Fragment from superoposterior VB may be displaced into canal
137
Facet joint dislocation
BILATERAL FACET JOINT DISLOCATION
- hyperflexion injury
- complete disruption of all spinal ligaments
- unstable, VB moves anteriorly
UNILATERAL
stable
138
Pathologic hip fracture
Lesser trochanter
Subtrochanteric NOF
139
Haemophilia joint findings
●Enlarged epiphysis + early joint fusion
● Soft tissue swelling
● Juxta-articular osteoporosis
● Erosion of articular surface with subchondral cysts
● Preservation of joint space
● Squared patella with widening of the intercondylar notch
Enlarged radial head + widened intercondylar notch
● Medial slanting of the tibiotalar joint and flattening of the condylar surface
● Low signal hypertrophied synovium (blood)
● Joint effusion.
140
Osteochondral defect grading
1: Stable - Covered by intact cartilage, Continuous with host bone D
2: Stable on Probing, Partial discontinuity with host bone
3: Unstable on Probing, Complete discontinuity of lesion.
4: Dislocated fragment
141
Diaphyseal aclasia association
Multiple osteochondromas
142
SAPHO
Synovitis Acne Pustulosis Hyperostosis Osteitis
Assoc: CRMO
143
Milwaukee
advanced rotator cuff tear + calcium crystals
LOOSE BODIES + subchondral sclerosis + superior subluxation of humerus
*NO OSTEOPHYTES*
144
PCL rupture
Increased laxity PCL
Reverse Segond - medial tibial plateau +/- medial meniscal injury
Arcuate sign= proximal fibular avulsion
145
Limbus vertebrae
Well defined VB ossicle
146
ACL graft
Angle too step = impingement
Angle too flat= lax, instability
147
Psoriatic arthritis
●● Interphalangeal joints typically involved
●● Marginal erosions> ‘pencil in cup’
●● Soft tissue swelling, ‘sausage digit’
●● Resorption of the terminal phalangeal tufts (acro-osteolysis)
●● Ivory phalynx
●● Periosteal reaction
●● Squaring of the vertebrae
●● Atlantoaxial subluxation
●● Joint space loss and ankylosis
●● Preservation of bone density and new bone formation
●● Enthesopathy (e.g. parasyndesmophytes—asymmetrical/unilateral paravertebral
ossification with sparing of the annulus fibrosus)
148
Salter Harris
I - through epiphysis
II- through physis + metaphysis
III- through physis + ephiphysis
IV- through physis, metaphysis + epiphysis
V- crush injury
149
Posterolateral corner
LCL + popliteus + popliteofibular ligament
Assoc: PCL RUPTURE, joint instability, cruciate graft failure
Suspicious findings: Segond frac, arcuate sign, IT band avulsion, anteromedial tibial plate frac
150
Carpel Tunnel findings
palmar bowing of the flexor retinaculum
nerve thickening at the carpal tunnel inlet (level of the pisiform)
nerve flattening at the carpal tunnel outlet (level of the hook of hamate)
increased size *MOST SENSITIVE*
>15 mm2 MRI, >11mm US
oedema or loss of fat within the carpal tunnel
neural oedema +/- contrast enhancement
151
Reactive arthritis
CAN LOOK SIMILAR TO PSORIATIC
*predominantly affects FEET*
Calcenus- erosions, fluffy periosteal reaction
Diffuse soft-tissue swelling, joint space loss, aggressive marginal erosions, and juxta-articular osteopenia.Normal mineralisation
can also affect hands and spine
Urethritis Conjunctivitis Arthritis
152
MCL rupture
VALGUS STRESS
153
GCT management
Extended curettage
154
Chondrosarcoma
COMMONEST PRIMARY BONE TUMOUR ADULTS
●● Pelvis and femur (40%), spine and ribs (25%), shoulder and proximal humerus (15%).
●● Central location, begins metaphysis > diaphysis.
●● Well-defined lytic lesion, endosteal scalloping and thinning/destruction of the cortex.
● RINGS + ARCS CALC
●● Large lesion (>5 cm).
●● Periositis (fluffy or lamellated).
●● Soft tissue mass.
*Hyperglycaemia paraneoplastic syndrome
155
Commonest location mandibular fracture
Parasymphyseal > body > angle ? condylar neck
156
Haemangioma features
Increase T1/T2, enhances
157
Holt Oram
distal radial hypoplasia + thumb defects + ASD
158
False negative bone scan
Prostate, MM, RCC, thyroid, aggressive anaplastic tumors, neuroblastoma, lymohoma
> use FDG PET/CT
*OSTEOCLASTIC*
159
Superscan
Non visualisation of kidneys
> metastatic prostate / breast cancer/ lymphoma
Metabolic: hyperparathyroidism and renal osteodystrophy
Metabolic= entire long bones increased uptake.
Mets= axial skeleton and proximal humeri and femora are primarily affected.
160
Stress fracture
+ve on all 3 phases of bone scan
161
Shin splints
Linearly increased uptake in the tibia on DELAYED phase
POSTEROMEDIAL
162
+ve on 3 phases of bone scan
Osteomyelitis
Ewings
Septic arthritis
Cellulitis = blood pool + soft tissue
163
Complex pain regional syndrome bone scan
Diffusely increased juxta-articular activity in multiple small joints on DELAYED (skeletal) images.
Blood pool and soft tissue phase = variable, most commonly both phases are increased.
164
Still disease
Variant of JIA < 5YO
acute febrile illness, rash, adenopathy, pericarditis, and mild arthralgias
165
Osteoporotic collapse MRI
low t1, HIGH T2, variable enhancement
malignancy: T1 signal diffusely low, more restricted diffusion, intense enhancement
166
Osteochondritis dissecans
Young boys
Lateral surface of medial condyle
167
Humeral head dislocation
Axillary nerve at risk
168
Commonest location osteoid osteoma
fEMORAL NECK
169
Toddlers fracture
Non displaced oblique fracture through tibial metadiaphysis
BONE SCAN GOOD AT DETECTING
170
Patella dislocation bony injury pattern
Inferomedial patella + lateral femoral condyle
Predisposing factors: trochlea dysplasia, patella alta, excessive lateralisation tibial tuberosity
171
Dense metaphyseal bands causes
●● Scurvy
●● Chronic disease
●● Chemotherapy
●● Radiation
●● Rickets
●● Osteopetrosis
●● Leukaemia
●● Lead poisoning
172
Scurvy feactures
● Ground-glass osteoporosis
● Sclerosis margins of the epiphysis (Wimberger sign)
●● Metaphyseal spurs (Pelcan spurs).
●● Dense metaphyseal lines (white lines of Frankel)
●● Trummerfield zone is a radiolucent zone on the diaphyseal side of the Frankel line.
●● ‘Pencil point’ cortical thinning.
●● Corner fractures
●● Exuberant periosteal reaction
●● Haemarthorosis.
●● ‘Hair on end’ skull vault.
173
TB Spondylitis
- Lower thoracic/ upper lumbar
- VB spared, IV disc destroyed
- Skip lesions
- Calcified psoas abscess
- Gibbus deformity
174
Sacral tumours
Commonest = chordoma
ABC + GCT
175
MPS
General features:
>Oval vertebral bodies with anterior beaking
> thickened clavicles and ribs
> undertubulated bones.
> Madelung deformity
> Thickened calvarium
> J-shaped sella.
> tall and flared iliac wings (opposite of achondroplasia).
>Wide tapering metacarpal bones.
HURLERS= ANTEROINFERIOR BEAKING
176
Absence/ erosion lateral calvicle
RA
MM
Mets
Cleidocranial dysplasia
PYKNODYSOSTOSIS
Hyperparathyroidism
177
Pyknodysostosis
DWARFISM + HYPOPLASTIC NAILS
●● Generalised increased density to the long bones (but medullary cavity is spare, unlike in osteopetrosis).
●● Thickened bone cortex.
●● Multiple healing fractures of varying ages.
●● Short distal phalanges.
●● Hypoplastic facial bones and sinuses
●● Wormian bones
●● Brachycephaly
●● Widened sutures
●● Resorption lateral clavicles
178
Ivory vertebrae
Lymphoma
Breast/ Prostate mets
Osteosarcoma
Carcinoid
Pagets
179
Tennis elbow
LaTeral epicondyle
Common exTensors
180
Causes of Erlenmeyer flask deformity
Lead poisoning
Gaucher disease
Niemann–Pick disease
Osteopetrosis
Metaphyseal dysplasia (Pyle disease)
‘Eematological’ (i.e. haematological causes—thalassaemia major [first 2 years of life])
181
Morton neuroma
3rd MT head
Low T1/T2
Compression of plantar digital nerve
182
Scapholunate dissociation
>3mm gap
>60 degree SL angle
normal Capitolunate angle
dorsal band = most important
183
Skull fracture
Longitudinal: Incudostapedial dislocation, conductive hearing loss
Tranverse: CNVII, sensorineural hearing loss, vascular injury
184
Location of epidermoid inclusion cyst
Distal pahalnx
185
De Quervain tenosynovitis
Ultrasound: Increased fluid within the first extensor tendon compartment
MRI: increased T2 signal in the tendon sheath
*extensor pollicis brevis + abductor pollicis longus*
186
Post prosthesis uptake
Normal for up to 12 months
infection <4 years
loosening > 4 years
for OM, do Tch99m labelled WCC + sulf colloid scan
187
Tarsal tunnel syndrome
compression of PTT
pain in first 3 toes
188
Nail Patella
Flared posterior iliac horns
189
Full thickness rotator cuff tear
contrast in glenohumeral bursa + subacromial/ subdeltoid bursa
190
-ve ulnar variance associations
Kienbock
ulnar impingement syndrome
191
Hutchinson fracture
intra-articular styloid fracture
assoc: scaphlunate + perilunate dissociation
192
Medial epicondylitis
flexor tendons, Golfers elbow
193
Pellegrini strieda
Post MCL injury
mineralisation near medial femoral condyle
194
Pitts Pitt
FIBROCYSTIC CHNAGE ANTEROSUPERIOR FEMORAL NECK
Low T1/ High T2
195
Liposclerosing myxofibroma
Intertrochanteric femur
Lytic + sclerotic margin
196
Tumoral calcinosis
Young black kids
Hereditary
Hip> elbow > shoulder
amorphous/ cloud like calc near joints
197
Pagets
Typically polyostotic and asymmetrical pattern.
●● Flame/grass-shaped metadiaphyseal lucencies in active phase— ‘osteoporosis circumscripta’.
●● Key features of inactive disease are bone expansion, thickening of the cortex and coarsening of the trabecular pattern.
● Cotton wool sclerosis in the skull.
● Picture frame appearance - thickening the whole way around the cortex CF renal osteodystrophy
● Ivory vertebra
● Coarsened trabeculations
BONE SCAN - markedly increased uptake all phases in active disease
●● Decreased uptake of technetium-99m sulphur colloid by bone marrow.
1. Malignant transformation a. Sarcoma, Multicentric giant cell tumour, Lymphoma
2. Insufficiency fractures
a. Convex side of a long bone, ‘banana fracture’
3. Nerve entrapment
a. Basilar impression compressing brainstem comression
b. Spinal stenosis
198
RA
● Bilateral, symmetrical polyarthritis
●Para-articular osteoporosis
● Soft tissue swelling + effusion =
●Loss of joint space
● Periarticular erosions + loss of cartilage
● Subcortical cysts
●Ankylosis, subluxation, deformity
●(MCP) joints
● Boutonnière deformity (fixed flexion joint + hyperextension DIP)
● Atlantoaxial subluxation
● Protrusion of odontoid peg.
● Scalloped erosion underneath clavicle
● Tapered distal clavicle
199
PVNS
PLAIN FILM
●● Early—soft tissue swelling and effusion.
●● Soft tissues appear dense = haemosiderin deposits.
●● Multiple sites of cystic radiolucencies/articular erosions due to bone invasion.
●● Scalloping of pre-femoral fat pad.
●● Soft tissue mass around the joint
●● Bone density is preserved.
●● Preservation of joint space.
NO CALCIFICATION
MRI
●● Large lobular intra-articular mass, low signal on both T1 and T2 (due to haemosiderin).
●● Haemorrhage is relatively common and causes blooming artefact on gradient echo.
●● Low signal effusion on all sequences is characteristic.
●● Other joint lesions low on T1 and T2: haemophilia, synovial haemangioma and
neuropathic osteoarthritis.
200
Cubital tunnel syndrome
- Repetitive valgus stress
- Ulnar nerve thickening
- Oedema flexor carpi ulnaris/ flexor digitorium profundus
Assoc: accessory anconeus epitrochlearis muscle
201
