MSK Flashcards
1
Q
DDx for acro-osteolysis (PINCH FO)
A
- Psoriasis, Pyknodysostosis, PVC exposure
- Injuries: frostbite, thermal injury, post traumatic
- Neuropathic: DM, Lesch-Nyhan syndrome
- CVD: scleroderma
- Hyperparathyroidism
- Familial (e.g. Hejdu-Cheney)
- Other (e.g. PVC exposure, progeria)
2
Q
DDx posterior element bone tumor (Lytic lesion)
A
- Osteoblastoma
- Osteoid osteoma
- ABC
- GCT
3
Q
DDx of chondrocalcinosis (“HOGWASH”)
A
- Hemochromatosis
- Ochronosis
- Gout
- Wilson’s disease
- Acromegaly
- PSEUDOGOUT (CPPD deposition) MCC
- Hyperparathyroidism
4
Q
What is an Essex-Lopresti fracture?
A
Comminuted and displaced fracture of the radial head AND subluxation or dislocation of the DRUJ
Due to longitudinal compression force
5
Q
What is a Monteggia fracture?
A
Fracture of the ulna and dislocation of the radial head
6
Q
What is a Galeazzi fracture?
A
Fracture of the radius at the junction of the middle and distal thirds
Assoc’d subluxation of the distal ulna
7
Q
What 3 injuries are associated with a Segond fracture?
A
(avulsion fracture at the insertion of the lateral capsular ligament)
ACL tear
MCL tear/strain
Medial meniscal tear
8
Q
What is cotton wool skull associated with?
A
Paget’s disease
9
Q
What is salt and pepper skull associated with?
A
Hyperparathyroidism
10
Q
What are findings in hyperparathyroidism / renal osteodystrophy?
A
- subperiosteal bone resorption (esp radial aspects of the proximal and middle phalanges of the 2nd and 3rd fingers)
- subligamentous resorption
- subchondral resorption
- rugger-jersey spine
- Brown tumors
- Salt and pepper skull
- chondroclacinosis
- terminal tuft erosion
- osteopenia
11
Q
In osteochondroma, what thickness of the cartilage cap is suspicious for malignant degeneration?
A
1.5 cm
12
Q
What is the chance of malignant transformation for a solitary osteochondroma? MHE?
A
1%
3-5%
13
Q
What conditions are associated with H-shaped vertebrae (Lincoln Log appearance)?
A
- Sickle cell anemia
- Gaucher disease
- Thalassemia
- Spherocytosis
14
Q
What is associated with picture frame vertebrae?
A
Paget disease
15
Q
What is associated with rugger jersey spine?
A
Hyperparathyroidism
16
Q
DDX ivory vertebra
A
- sclerotic metastasis
- lymphoma
- Paget disease
- chordoma
- mastocytosis
17
Q
DDx lucent lesion in calcaneous
A
- intraosseous lipoma
- UBC
- GCT
- pseudolesion
18
Q
DDx lucent lesion in the proximal femur
A
- intraosseous lipoma
- fibrous dysplasia
- liposclerosing myxofibrous tumor (LSMFT)
- UBC
19
Q
What is Mazabraud syndrome?
A
- polyostotic fibrous dysplasia
- multiple soft tissue myxomas (usually in large muscle groups)
20
Q
What is McCune Albright Syndrome?
A
- Fibrous dysplasia
- Cafe au lait spots
- Precocious puberty
21
Q
DDx fluid fluid levels in tumors
A
- ABC
- GCT
- Telangiectatic osteosarcoma
- Chondroblastoma
- Fibrous dysplasia
22
Q
What is Ollier syndrome?
A
Multiple enchondromas
Does not have increased malignant degeneration
23
Q
What is Maffucci syndrome?
A
Multiple enchondromas associated with soft tissue hemangiomas
Increased risk of malignant degeneration
24
Q
What are 4 discriminators for GCT?
A
1) Epiphyses must be closed
2) Must abut the articular surface
3) Must be well-defined with a non-sclerotic margin
4) Must be eccentric
Some rules do not apply to flat bones
25
What findings characterize Scheuermann disease?
3 contiguous disc level having:
1) Mild anterior wedging (>5 degrees)
2) endplate irregularity
3) Schmorl nodes
4) kyphosis
26
DDx for sacral mass
- chordoma
- metastasis
- plasmacytoma
- lymphoma
- sarcoma
- Teratoma
27
DDx for lesions of the phalangeal tufts
- epidermoid inclusion cyst
- glomus tumor
- foreign body granuloma
- periosteal chondroma
- septic arthritis / osteomyelitis
- brown tumor
28
DDx for metaphyseal fraying
- healing rickets
- hypophosphatemia
- renal disease
- metaphyseal chondrodysplasia
29
What are the boundaries of the quadrilateral space?
- teres minor (superiorly)
- teres major (inferiorly)
- humerus (laterally)
- long head of the triceps (medially)
30
What muscles are involved in quadrilateral space syndrome?
teres minor
+/- deltoid muscle
(axillary nerve affected)
31
What is Parsonage-Turner syndrome?
aka "acute brachial neuritis": Refers to an idiopathic denervation of the shoulder.
- Can involve any of the shoulder muscles.
- 97% cases involve the suprascapular nerve.
32
DDx madelung deformity
"HITDOC"
- Hurler syndrome
- Infection
- Trauma (Salter 5)
- Dyschondroestosis
- Osteochondroma (MHE)
- Congenital (Turner's syndrome)
33
DDx distal clavicular erosion
| "SHIRT Pocket"
RA
Hyperparathyroidism
Post traumatic osteolysis
```
"SHIRT Pocket"
Scleroderma
HPT
Infection (osteomyelitis)
RA
Trauma
Progeria
```
34
What are the types of psoriatic arthritis?
- Symmetric
- Asymmetric
- Distal interphalangeal predominant (DIP) psoriatic arthritis
- Spondylitis
- Arthritis mutilans
35
DDx for Erlenmeyer flask deformity
CHONG
Craniometaphyseal dysplasias (e.g. Pyle disease)
Hemoglobinopathies (sickle cell, thalassemia)
Ostopetrosis
Niemann-Pick disease
Gaucher disease
36
DDx for osteonecrosis
- Sickle cell disease
- Corticosteroids
- Idiopathic
- Gaucher disease
- Trauma
- Alcoholism
- Collagen vascular diseases
- Renal transplantation
- Pancreatitis
37
What age groups are affected by transient osteoporosis?
```
pregnant women (3rd trimester)
middle aged men (40-55 yo)
```
38
What muscles does the suprascapular nerve supply?
supraspinatus
| infraspinatus
39
DDx of extensive soft tissue calcification "TIC MTV"
```
Tumoral- neoplasm, tumoral calcinosis
Inflammation- CVD, infection (parasites)
Congenital- Myositis ossificans progressiva, Ehlers Danlos
Metabolic- HPT, CPPD, DM
Trauma- dystrophic, burn, MO
Vascular
```
```
Dermatomyositis
Polymyositis
Mixed connective tissue disease (calcinosis universalis)
Scleroderma
Burns
Calcific myonecrosis
Tumoral calcinosis
Hemangiomatosis
Parasitic infection
```
40
What are the radiographic features of chronic tophaceous gout (7)?
1. Tophi
2. Normal mineralization
3. Joint space preservation
4. Punched out juxta-articular erosions with sclerotic borders
5. Overhanging edges
6. Asymmetric polyarticular distribution
7. Distribution in feet, ankles, knees, hands, and elbows (decreasing frequency)
41
DDx intra-articular mass of the knee
PVNS (Localized)
Synovial hemangioma
Synovial chondromatosis
Synovial sarcoma
42
DDx for synovial hypertrophy and bone erosions
```
PVNS
Synovial osteochondromatosis
Amyloid arthropathy
TB
Synovial hemangiomatosis
```
43
What is Preiser's disease?
Idiopathic AVN of the scaphoid
44
What is the normal thickness of the plantar fascia?
Shouldn't exceed 4 mm
45
DDx concentric hip narrowing
- RA (seropositive), JIA
- Ankylosing spondylitis (seronegative)
- (CPPD, gout)
- Paget's
46
DDx for multiple lucent bone lesions (FEEMHI)
- Fibrous dysplasia (McCune Albright vs. Mazabraud)
- Enchondroma (Ollier vs. Maffuci)
- Eosinophilic granuloma
- Mets/Myeloma
- Hyperparathyroidism (HPT with Brown tumors)
- Infection
47
DDx epiphyseal lesions
- Chondroblastoma
- Infection
- GCT
- Geode (subchondral cyst)
48
DDx sacroiliits
```
Psoriatic arthritis
Ankylosing spondylitis
IBD associated arthritis
Reactive arthritis
Septic joint (unilateral)
```
49
What is de Quervain's tenosynovitis?
Tendinitis and tenosynovitis of the APL and EPB (first extensor compartment).
Occurs at or just proximal to the radial styloid process.
50
What is Chopart's joint?
Mid-tarsal joints (e.g. calcaneocuboid joint and talonavicular joint)
51
What are causes for AVN (e.g. of the hip)?
- Trauma
- Corticosteroids
- Sickle cell disease
- Lupus
- Idiopathic
- Caisson disease
- Radiotherapy
- Pancreatitis
52
What is Kohler disease?
AVN of the navicular, typically in children.
| In adults, osteonecrosis of the navicular is called Mueller Weiss syndrome.
53
What is Panner disease?
Osteochondrosis of the capitellum (age 5-10)
54
What is Kummell disease?
vertebral body AVN
55
DDx apophyseal (epiphyseal) lesions
```
"George eats a chinese bok choy"
GCT
EG
ABC
Chondroblastoma
Brodie's abscess
Clear cell chondrosarcoma
```
56
What is Sever disease?
calcaneal apophysitis (occurs in children and young adolescents). Usually see edema at the calcaneal apophysis inferiorly. Self-limited; conservative treatment typically.
57
What is Baxter neuropathy/syndrome?
Nerve entrapment syndrome resulting from the compression of the inferior calcaneal nerve (Baxter nerve). Abnormal signal or atrophy of the abductor digiti minimi.
58
What is a Chopart fracture?
Fracture/dislocation of the mid-tarsal joint of the foot (talonavicular and calcaneocuboid joints). May be a/w fractures of the calcaneus, cuboid and navicular.
59
What is a normal Boehler's angle?
20 to 40 degrees
60
What is the typical appearance of bipartite patella?
Sclerotic zigzag line with fragment at the superolateral corner of the patella.
61
What are 2 MRI signs of AVN?
- double line sign
| - rim sign
62
What do pyrophosphate (CPPD) crystals look like at microscopy?
Polarized light microscopy demonstrates rhomboid crystals with weak positive birefringence.
63
What do urate crystals look like at microscopy?
Monosodium urate crystals are needle shaped and demonstrate strong negative birefringence.
64
What is the clinical triad associated with hypertrophic osteoarthropathy?
- digital clubbing
- extremity enlargement secondary to periosteal new bone formation
- painful, swollen joints
65
What is florid reactive periostitis?
aka parosteal or nodular fasciitis. It is an unusual bone-producing lesion that may be confused with an infectious or neoplastic process. It typically involves the small bones of the hands and feet. Radiographically characterized by periosteal reaction that may progress to an ossified mass. Tx = local excision
66
What are XR findings of sarcoidosis?
- Cystic bone lesions with well-defined margins
- lytic bone lesions with periosteal reaction
- remodeling of the cortex of phalanges (concave shaft into a tubular)
- sclerotic bone lesions
- lace-like pattern
- osteopenia/osteoporosis
- tenosynovitis/dactylitis
67
Which joints can exhibit erosions with osteoarthritis?
- acromioclavicular joint
- SI joint
- TMJ
68
What are the diagnostic criteria for rheumatoid arthritis?
(Need 4 of 7)
1) Morning stiffness > 1 HR
2) Synovitis 3 or more joints
3) Hand involvement
4) Symmetric distribution
5) Subcutaneous nodules
6) + rheumatoid factor
7) Radiographic changes
69
What are the classic HLA-B27 arthropathies?
- Psoriasis
- Ankylosing spondylitis
- IBD-associated arthropathy
- Reactive arthritis
70
For lucent bone lesions, what diagnoses should be included in EVERY ddx? (40 years)
Less than 30 years of age: Infection, EG
| Greater than 40 years of age: Infection; mets/myeloma
71
DDx localized gigantism
- Macrodystrophia lipomatosa
- NF 1
- Klippel-Trenaunay-Weber syndrome
- Lymphangiomatosis
- Proteus syndrome (aka Wiedemann syndrome)
Also consider exostoses:
- BPOP- bizarre parosteal osteochondromatous proliferation (aka Nora lesion)
- Osteochondroma
72
What is Jaccoud athropathy?
- Jaccoud arthropathy is a deforming non-erosive arthropathy characterised by ulnar deviation of the second to 5th fingers with MCP subluxation.
- It was traditionally described as occurring post rheumatic fever. It is also seen in association with SLE and several other rheumatic and nonrheumatic conditions. Thought to be related to ligamentous laxity.
73
What is tennis leg?
Although tennis leg is fairly common, whether it represents a single entity or not is still debated. It involves injury to the muscles of the calf (superficial posterior compartment of the leg) with two mechanisms identified:
1) tear of the myotendinous junction of the medial head of gastrocnemius
2) rupture of the plantaris tendon (now thought to be a less or uncommon cause
Both findings have been found in isolation or together.
74
What is a Romanus lesion?
- MRI equivalent of "shiny corner sign"
- The Romanus lesion represents an early finding in inflammatory spondyloarthropathies, such as ankylosing spondylitis and enteropathic arthritis, and appears as irregularity and erosion involving the anterior and posterior edges of the vertebral endplates. Healing response to these inflammatory erosions appears radiographically as reactive sclerosis, which is known as the shiny corner sign.
75
What is an Andersson lesion?
- Andersson lesions refer to inflammatory involvement of the intervertebral discs by spondyloarthritis.
- On MR imaging, these lesions are depicted as disc-related signal-intensity abnormalities of one or both vertebral halves of a discovertebral unit; they appear hyperintense on STIR images and hypointense on T1-weighted images, where they are often hemispherically shaped.
76
DDx for MCP predominant arthritis
More common: RA, pyrophosphate arthropathy
Less common: Hemochromatosis, robust RA, JIA, SLE
Least common: Jaccoud arthropathy
77
What is Trevor disease?
- aka Dysplasia epiphysealis hemimelica
- extremely rare (1:1,000,000), non-hereditary disease that is characterized by osteochondromas arising from the epiphyses
78
What are the MRI findings of the 4 stages of stress fracture or stress reaction?
Grade 1: periosteal edema
Grade 2: periosteal and medullary edema
Grade 3: grade 2 plus marrow abnormalities on T1
Grade 4: definite line on T1 with edema
79
What is a Tillaux fracture?
A Tillaux fracture is a Salter type 3 avulsion of the anterolateral aspect of the distal tibial epiphysis.
80
What is a triplane fracture?
A triplane fracture is a coronally oriented fracture of the distal metaphysis of the tibia, a horizontally oriented fracture of the lateral aspect of the physis, and a sagitally oriented fracture of the distal epiphysis. The injury results in part due to the partially fused tibial physis, closure progressing medial to lateral.
81
What is a pilon fracture?
A pilon fracture is a comminuted fracture of the distal tibia and tibial plafond due to impaction of the talus into the tibia.
82
What can give rise to an aneurysmal bone cyst secondarily?
- NOF
- GCT
- fibrous dysplasia
- UBC
83
DDx sclerotic bone lesions
- Metastasis (prostate, breast)
- lymphoma
- osteoma, osteoid osteoma, osteoblastoma
- healed benign or malignant bone lesion
- primary bone sarcoma
84
DDx expansile lytic bone lesion
- GCT
- ABC
- mets
- fibrous dysplasia
- intraosseous ganglion cyst
- Brown tumor
- infeciton
85
DDx lytic skull lesions
- Multiple myeloma
- Lytic metastases (irregular, ill-defined; breast, lung, renal, thyroid)
- Leukemia, Lymphoma
- EG (bevelled edges)
- HPT (salt and pepper skull, fine granular)
- Paget's- osteoporosis circumscripta
- Solitary lesion: plasmacytoma, osteomyelitis, burr hole
86
DDx pelvic lytic lesion
- Sarcoma: fibrous histiocytoma, synovial sarcoma, rhabdomyosarcoma/liposarcoma, telangiectatic osteosarcoma
- Large solitary met
- Plasmacytoma
87
DDx exophytic bony lesions
- Osteochondroma
- Surface osteosarcoma
- BPOP (bizarre parosteal osteochondromatous proliferation, aka Nora lesion); typically seen in the hands and feet
- Florid periostitis
88
DDx expansile rib lesion
- Fibrous dysplasia
- Plasmacytoma, MM
- Metastatic disease
- Chondrosarcoma
89
DDx diffuse periosteal thickening
- Stress fractures and trauma
- Paget's disease
- HPT
- Venous and arterial insufficiency
- Hypertrophic osteoarthropathy
90
At which interspace is Morton neuroma most common?
3rd interspace (between the 3rd and 4th toes). The 2nd intermetatarsal space is second most common.
91
DDx gracile bones
"NIMROD"
- NF
- immobilization/paralysis
- muscular dystrophy
- RA (JIA)
- osteogenesis imperfecta
- dysplasia (e.g. Marfan, homocysteinuria)
92
DDx brachymetatarsia
```
Turner syndrome
Down syndrome (trisomy 21)
Pseudohypoparathyroidism
Pseudo pseudohypoparathyroidism
```
93
DDx focal cortical thickening
- Periosteal reaction (e.g. Hypertrophic pulmonary osteoarthropathy)
- BPOP
- florid reactive periostitis
- Periosteal chondrosarcoma
- parosteal osteosarcoma
- benign etiologies: healed NOF, osteoid osteoma, healed fracture
94
DDx short fourth and fifth metacarpals
- Turner syndrome
- Down syndrome
- Pseudohypoparathyroidism
- pseudopseudohypoparathyroidism
- idiopathic
- post traumatic
- sickle cell
- post infective (e.g. Osteomyelitis)
- basal cell nevus syndrome
- hereditary multiple exostosis
- homocystinuria
95
What is a normal acromiohumeral interval?
->12 mm: shoulder dislocation; inferior subluxation (e.g. from joint effusion)
-9-10 mm (range 8-12mm): normal
-6-7 mm: thinning of supraspinatus tendon
-
96
What ulnar deviation is associated with Kienbock's?
75% associated with ulnar negative variance
97
DDx calvarial thickening
- idiopathic
- chronic ventricular shunting
- Paget disease
- anaemias (e.g. Sickle cell)
- osteopetrosis
- hyperparathyroidism
- antiepileptics (e.g. phenytoin)
- cerebral arteriovenous malformations
- rare certain sclerosing bone dysplasia (e.g. hyperostosis cortical generalisata (van Buchem disease))
98
Dorsal Intercalated Segmental Instability (DISI) occurs with injury to what ligament?
DISI occurs with scapholunate ligament (SLL) injury and unstable scaphoid fractures.
Scapholunate angle is typically >60 degrees (on the lateral XR).
99
Volar Intercalated Segmental Instability (VISI) occurs with injury to what ligament?
VISI occurs with lunotriquetral ligament injury
| Scapholunate angle is typically
100
Where does a bisphosphonate-related fracture occur?
```
-Subtrochanteric fracture
X-ray findings include?
-Focal lateral cortical thickening
-Transverse fracture orientation
-Medial spike
-Lack of comminution
```
101
What is ulnar abutment or impaction syndrome?
Ulnar impaction syndrome, also known as ulnar abutment, is a degenerative wrist condition caused by the ulnar head impacting upon the ulnar-sided carpus with injury to the triangular fibrocartilage complex (TFCC).
-See bone changes at the radial aspect of the triquetrum, ulnar side of the lunate or the distal ulna.
102
What is ulnar impingement syndrome?
Ulnar impingement syndrome is a wrist condition caused by a shortened distal ulna (negative ulnar variance) impinging on the distal radius proximal to the sigmoid notch. The syndrome is distinct from ulnar impaction syndrome, which typically occurs due to a long ulna (positive ulnar variance) impacting upon the triangular fibrocartilage (TFC) and lunate.
103
DDx short 4th and 5th metacarpals
- Post-trauma
- Post-infectious (e.g. osteomyelitis, TB dactylics)
- Turner syndrome
- pseudohypoparathryoidism
- pseudopseudohypoparathyroidism
- Basal cell nevus syndrome (Gorlin syndrome)
- Sickle cell disease with secondary infarction
- homocystinuria
104
DDx blastic metastases
5 B's Lick Pollen
- Brain (medulloblastoma)
- Breast
- Bronchus
- Bowel (esp. carcinoid)
- Bladder
- Lymphoma
- Prostate
105
What are features of pyknodysostosis?
- Osteosclerosis
- Short stature
- Hypoplasia of the mandible
- Dysplasia of skull bones and delayed closure of sutures
- Partial aplasia of terminal phalanges and hypoplasia of nails
106
DDx for arthritis mutilans
- RA
- JIA if paediatrics
- neuropathic joint (Charcot)
- septic arthritis
- hemophilia
- psoriatic arthritis
107
Findings in Fong's disease?
-posterior iliac horns
-patellar hypoplasia/aplasia
Other associations include aplasia/hypoplasia of the thumb and index fingernails, and radial head/capitellum hypoplasia
108
What makes up the arcuate ligament complex?
- arcuate ligament
- popliteo-fibular ligament
- fabello-fibular ligament
109
What are findings of adhesive capsulitis?
-MRI may be normal
-T1WI:
*Low signal fibrosis in rotator interval
*Thick coracohumeral ligament
*Thick capsule in rotator interval and axillary recess
*"Subcoracoid triangle" sign: loss of fat in triangle between coracohumeral ligament, coracoid process, and joint capsule
T2WI:
*incr signal in rotator interval and joint capsule; pericapsular edema
-MR arthrography:
*=4 mm
*Thick rotator interval joint capsule >=7 mm
*Decreased vol of axillary recess
110
DDx periostitis
- primary hypertrophic osteoarthropathy (pachydermoperiostosis)
- secondary HPOA (lung cancer, CF, bronchiectasis)
- thyroid acropachy
- trauma
- venous stasis
111
DDx multiple calcified intraarticular bodies
- primary synovial osteochondromatosis
- rice bodies in RA or TB
- multiple loose bodies related to OA
112
Describe the course and anatomy of the ACL
- ACL originates at posterolateral intercondlar notch, extends anteromedially, inserts at interspinous tibia and medial tibial spine.
- ACL consists of 2 bundles: anteromedial and posterolateral
113
Describe the course of the PCL
-PCL originates at medial aspect of intercondylar notch, extends posterolaterally, inserts extra-articularly on posterior cortex of proximal tibia.
114
What is the measurement for a thickened heel pad in acromegaly?
Heel pad thickness >25 mm
115
DDx for thickened heel pad
"MAD COP"
- Myxedema
- Acromegaly
- Drugs (Phenytoin therapy)
- Callus formation
- Obesity
- Peripheral edema
116
What is the CRAB criteria for multiple myeloma?
hyperCalcemia
Renal insufficiency
Anemia
Bone lesions
117
Most common primary malignant rib lesion in an adult
chondrosarcoma
118
What bone tumors cause excessive bone marrow edema?
Osteoid osteoma
Osteoblastoma
Chondroblastoma
119
What is considered a "massive" rotator cuff tear?
2 or more tendons involved (usually at least supraspinatus and infraspinatus) and > 5 cm
120
What are considered epiphyseal equivalents?
Trochanter, tuberosity, calcaneus, vertebral body
121
DDx skin tumor
- DFSP (dermato fibrosarcoma protuberans. Invades subcutaneous tissues)
- neurofibromas
- melanoma
- metastases
122
DDx chronic monoarticular and polyarticular disease
- Gout
- RA
- CPPD
- hemophilia
- PVNS
- synovial chondromatosis
- amyloidosis
123
DDx intervertebral disc calcification
- CPPD
- hemochromatosis
- hyperparathyroidism
- acromegaly
- amyloidosis
- ochronosis
124
DDx diffuse sclerotic bones
3MS PROOF
- Myelofibrosis
- Mastocytosis
- Malignancy (metastases, lymphoma/leukemia)
- Sickle cell disease
- Paget's, Pyknodysotosis
- Renal osteodystrophy
- Osteopetrosis
- Other (Osteopoikilosis, osteopathia striata, melorheostosis, hyperthyroidism, hypoparathyroidism, athletes)
- Fluorosis
125
Causes for neuropathic joint
"DS6"
- Diabetes
- Spinal cord injury
- Syringomyelia
- Spina bifida
- Syphilis
- Steroids
- Scleroderma
126
DDx acetabular protrusio
"PROT": Includes the most common causes
- P: Paget disease
- R: rheumatoid arthritis (and other arthritides such as osteoarthritis, ankylosing spondylitis, juvenile idiopathic arthritis, crystalline arthropathy)
- O: osteomalacia, osteogenesis imperfecta
- T: trauma
127
DDx cortical proliferation
- stress fracture
- osteochondroma
- osteoid osteoma
- periosteal osteosarcoma
- venous stasis
- chronic OM
- melerrheostosis
- osteopathia striatum
128
DDx bullet-shaped vertebral bodies
- Morquio's
- achondroplasia
- hypothyroidism
129
Findings of Achondroplasia
- progressive decrease in interpedicular distance in lumbar spine
- metaphyseal flaring
- bullet-shaped vertebral bodies
- posterior vertebral body scalloping
- Short metacarpals and wide phalanges ("trident hand")
- Short femur/humerus bones (rhizomelic shortening)
- Tombstone iliac wings
- Trident acetabulum
* *most common skeletal dysplasia
130
DDx metaphyseal dense lines
"DENSE LINES"
- D: vitamin D intoxication
- E: elemental arsenic and other heavy metals (e.g. LEAD)
- N: normal variant
- S: systemic illness
- E: estrogen to mother during pregnancy
- L: leukemia
- I: infection (TORCH)
- N: never forget healed rickets
- E: early hypothyroidism
- S: scurvy, congenital Syphilis, sickle cell disease
131
What are associations related to abdominal wall desmoid?
- Gardner's syndrome
- FAP
- Prior surgery at the site
