MSK

Question 1

osteogenesis imperfecta types

Answer 1

collagen disorder. decreased synth (type 1, 3&4. AD) or abnormal collagen (type 2. AR).

1. acquired mutation, not present at birth (2-6yo). normal lifespan with increased # during infancy. most common. otosclerosis (deaf), blue sclera, teeth abno.
2. incompatible with life. multiple intrauterine #s. death 2nd Pulm hypoplasia.
3. same as type 1 but present birth with growth retardation.
4. same as type 1 but present birth with short stature. less otosclerosis, sclera normal, only mild osteoporosis and #.

Question 2

osteoporosis
osteomalacia
Vitamin d def

Answer 2

osteoporosis. n bone mineralization and matrix, decreased volume
osteomalacia. n bone matrix but doesn’t mineralized. get cartilage overgrowth (flaring metaph and Ricketts rosary ribs).
vit c def. scurvy. decreased matrix with n mineralization. fragile vessels. collagen x link disorder.

Question 3

osteoporosis types

Answer 3

1. Juvenile
   Post menopausal. f>m 6.1. decreased oestrogen with increased osteoclast and turnover bone. cancellous > cortical
   Senile. older >65. f>m 2.1. increased osteoblast with decreased turnover. cancellous = cortical

2ndry. crf, congenital (osteogenesis imperfecta, sickle cell), etoh, malabsorption or nutrition, steroids, malignancy, endo (hyper or hypoparathyroid), immune (RA, SLE)

Question 4

rickets

Answer 4

osteomalacia
decreased vit d
decreased intake/ sunlight, decreased synthesis kidney (1.25 dihydroxycholcalciferol crf), resistance to vit d.
n matrix with decreased mineralization so cartilage overgrowth with weak bendy bones (looser zones and#, bowed, rickets rosary ribs, metaph flaring and fraying)

Question 5

scurvy/vit c

Answer 5

collagen x link disorder
normal mineralization bone but decreased matrix
lucent bands, subperiosyeal haem, joint haem, pencil thin cortex and metaph cupping/spur

Question 6

pagets

Answer 6

increased bone turnover with disordered remodeling
?cause, ? chronic paramyxoid infection
3 phases:
1. lytic. increased osteoclast, increased vascularity, increased breakdown. cortex and trabecular thin
2. mixed. osteoclast and vascularity decrease with osteoblast increase. irregular disorganized remodeling with thick trabecular and cortex. mosaic
3. burnout. uniform Sclerotic. decreased cellular activity

axial skeleton and long bones.
malig degeneration to fibrosarc, chondrosarcoma, osteosarcoma.

Question 7

AVN causes

Answer 7

epiphyseal. cartilage preserved but wedge shaped epiphyseal infect with subchondral collapse
metadiaphyseal. indolent. cortex preserved
causes: ASEPTIC
Anaemia (sickle cell), Steroids, Etoh, Pancreatitis, trauma, Idiopathic, CVD

Question 8

osteomyelitis bugs

Answer 8

neonates. GBStaph . epiphyseal and metaph
kids. h. influenza. don’t cross growth plate. metaph only
adults. fused growth plate so cross. staph aureus
IVDU. spine, SIJ, sternoclavicular.
bodies abscess. chronic walled off abscess
involcrum (abscess with Sclerotic wall), sequestrum (central bone), cloaca (tract to cortex/joint).

Question 9

TB osteomyelitis

Answer 9

spares IV discs. 
travels under ALL and multilevel
psoas spread
\+/- ca+
also knees, hips, other big joints. looks like gout on steroids.

Question 10

RA

Answer 10

T CD4 cell autoimmune chronic systemic inflamm
joints. synovitis 》erosion. proximal hands and feet then larger joints (spares hips and Lumbar spine).
pannus. inflammatory ST
Lungs. nodules (can be large and cavitating), sensitive to silicosis = caplan. UIP, effusion
heart. peri or myocarditis
skin. nodules on pressure areas
spleenomegaly (felty) with neutropaenia

Question 11

seronegative spondyloarthropathy

Answer 11

HLA B27, Rh -ve
PAIR. Psoriasis, Ank spon, Inflammatory (IBD), Reactive/Reiter
SIJ, inflamm arthropathy symmetric, enthesopathy and bone proliferation, syndesmophytes

Question 12

Ank spon

Answer 12

bamboo spine
dagger spine
shiny corners
Sq.  VB
enthesophytes
SIJ
anterolateral hatchet prox humerus

Question 13

Reactive arthritis

Answer 13

feet>hands
triad. can’t see (conjunctivitis), can’t wee (uveitis ), can’t climb a tree
2-3 weeks post infection. salmonella

Question 14

psoriatic arthritis

Answer 14

hands > feet
pencil in cup
new bone proliferation
sausage digit
ivory phalanx

Question 15

SLE

Answer 15

multisystemic autoimmune vasculitis

non erosive joints, ligament laxity and subluxation,AVN
anti dsDNA and smith antibodies
Pulm haem, bone infarct, pericardial or pleural effusion , enteritis, discoid or malar rash, oral ulcers

Question 16

gout

Answer 16

accumulation of monosodium irate crystals in joints and kidneys
crystals not water soluble. yellow, sharp, bifringent -ve
kidneys. medulla. CRF and calculator
joint. recurrent inflamm with synovial thickening, periarticular eroisions and pannus
cause.1. 95%primary. genetic predisposition
2ndry. increased prod (mm, tumour, infection), decreased excretion (crf)

Question 17

CPPD

Answer 17

Calcium Pyrophosphate depo in joints..chalky white
unknown aetiology
chondrocalcinosis, hook osteophytes 2/3rd MCP

Question 18

PVNS cf synovial chondromatosis

Answer 18

pigmented villonodular synovitis
PVNS. 10-30yo.don’t ca+. diffuse (big joints, knee) or focal (hands, wrists tendon sheath) haemosiderin depo, villonodular finger like projections synovial membrane.
synovial.chondromatosis. older 30-50yo. ca+ intra articular foreign bodies.

Question 19

multiple enchondromas

Answer 19

olliers.
diaphyseal medullary expansion. 
short tubular bones of fingers and feet
bilateral and asymmetric
associated.  panc and granulosa cell ovarian tumor

Question 20

acromegally

Answer 20

2nd pit adenoma. growth overstimulation
thick skull with big sinuses
big jaw
hypertrophy spinal ligs
VB #s
distal phalanx spade
heal pad thick

Question 21

hyperparathyroid

Answer 21

1. adenoma or hyperplasia of parathyroid
2. Renal cause (renal osteodystrophy)
3. parathyroid adenoma due to chronic hyperparathyroid. doesn’t return to n once stimulus fixed

subperiosteal bone resorption. radial side 2&3 digit, med tibia, humerus and femur
subchondral resorption. distal clavicles, pub symph and SIJ erosion
subligamentous resorption. Inferior calcaneous, is children tuberosity
acroosteolysis, ST ca+, superscan, superior and inferior rib notch
** 2ndry (renal osteodystrophy) also get rugger jersey spine

Question 22

DISH cf Ank spon

Answer 22

DISH.>4 flowing osteophytes VB R>L.
OPLL ca+
enthesopathy
NO SIJ (Ank spon does)

Question 23

insufficiency fracture

Answer 23

vertebral crush or wedge
sacral H
NOF
proximal 1/3 femur bisphosphinate
public rami
calcaneous under
sternum 
*xray often n. do bonescan for  increased activity

Question 24

chondrocalcinosis

Answer 24

CPPD most common
crystals, cation, cartilage destruction
crystals. CPPD, gout, HADD
cations. wilsons, hyperparathyroid, iron (haemachromatosis)
Cartilage destruction. OA, acromegaly, trauma

Question 25

sacral mass

Answer 25

chordoma chondrosarcoma GCT plasmacytoma

Question 26

modic changes

Answer 26

1. oedema. dark bright 2. fat. bright bright 3. sclerosis. dark dark

Question 27

tarlov cyst

Answer 27

s2 and s3 causes erosion 25% symptomatic, rest not.

Question 28

femeroacetabular impingement

Answer 28

cam. overgrowth acetabulum | pincer. NOF bulge

Question 29

Morton neuroma

Answer 29

3rd and 4th metatarsal head (3rd interspace) 2nd metatarsal interspace less common (2nd and 3rd MT heads) chronic entrapment plantar digital nn by intermetatarsal lig. fibrous, low T1 and T2 ,hypoechoic but enhances

Question 30

hypothyroid

Answer 30

delayed skeletal maturation. assessment age with Greulich and Pyle cortical thickening stipple epiphysis (lots of ossifucation centres) small or absent epiphyseal growth centre

Question 31

Achilles tendon tear

Answer 31

2-6cm from insertion | can't get tenosinovitis as no synovial sheath, but get fluid around

Question 32

Fibrous dysplasia. | 4 patterns

Answer 32

monostotic polyostotic craniofacial cherubism - mandible and maxillary only

Question 33

McCune albright

Answer 33

polyostotic fibrous dysplasia (unilateral usually) cafe au lait spots precocious puberty, hypercortisol/cushing

Question 34

meniscus cyst

Answer 34

adj to anterior horn lateral meniscus. associated with complex tear adjacent to posterior horn medial meniscus. associated with horizontal tear

Question 35

posterolateral corner

Answer 35

4 main structures: Lat colat, pop mm, popliteofib lig, biceps femoris. ACL > PCL

Question 36

O'Donoghue unhappy triad

Answer 36

ACL mcl med meniscal tear pivot shift injury. basketball.

Question 37

Blount disease

Answer 37

osteoneceosis of medial tibial condyle <> big (obese), black, boys.

Question 38

erlenmeyer flask

Answer 38

TOP DOG Thalassemia,osteopetrosis, Pyle disease ( metaphyseal bone dysplasia), Diaphyseal eclasia (multiple hereditary exostoses), olliers, gauchers lead poisoning, fibrous dysplasia, rickets, Achondroplasia

Question 39

rotator cuff us

Answer 39

supra spin do in int. rotation. xray do extra rotation. ant tear 》posterior. 1cm medial to insertion. associated. type 3 acrimion

Question 40

rib notching

Answer 40

superior: CTDs, Maran, NF, OI, hyperparathyroid inferior: enlarged collateral vessels (aortic coarct or thrombus, Blalock taussig, Pulm aa stenosis, svc obst, avm ) neurogenic tumor (NF, neuroma) osseous (hyperparathyroid, Thalassemia)

Question 41

Kummel disease

Answer 41

AVN of VB post wedge # non union 2 weeks post major trauma lower t and upper l spine IV vacume cleft and fluid level

Question 42

Ewing cw osteosarcoma

Answer 42

Ewing is younger age group and diaphyseal. ST>bone OS is older and metaphyseal. do an MRI to assess for local extent, skip lesions, which mm compartment in CT chest for mets. dense and Ca+ in osteosarcoma

Question 43

osteosarcoma subtypes

Answer 43

conventional telangectatic. worst prog. lytic, fluid/necrotic filled peristaltic. around bone. diaphyseal paraosteal. best prog. outer periosteum with cleft between. older 20- 50yo primary associated with retinoblastoma and le fraumeni 2ndry from fiborous dysplasia, pagets, rxt, OM

Question 44

adimantinoma

Answer 44

anterior tibia cystic multilocular lesion in teen boy | locally aggressive

Question 45

elastofibroma

Answer 45

Fibrous mass between scapula and chest wall 2ndry to friction. old lady benign

Question 46

ST mass

Answer 46

rhabdomyosarcoma - most common in kids (most common bladder, but can occur anywhere) synovial cell sarcoma - near joint but not within. +/- ca+. liposarcoma - 40-60yo. extremities and retroperitoneal. well cx looks like lipoma Malignant fiborous histiocytoma - most common ST sarcoma in adult. Extremities and retroperitoneal. 2nd to pagets or rxt. aggressive. Fibromatoses - nodular. Palmar (dupuytren) plantar penis (peyronie ) mm shoulder, chest wall, back, thigh, h&n messenteric

Question 47

spondylolisthesis grades

Answer 47

1. 0-25% 2. 25-50% 3. 50-75% 4. 75-100%

Question 48

mm lesion with high T2 and rim c+ ddx

Answer 48

abscess haematoma sarcoma *no hx trauma or infection... sarcoma needs to be excluded.

Question 49

Jones fracture

Answer 49

at least 2cm distal to joint 5th MC base | don't involve the joint

Question 50

Sacroiliitis

Answer 50

PAIR psoriasis, Ank spon (starts inferior), IBD, Reactive gout - Sclerotic erosions - good differentiator brucellosis, JCA, whipples

Question 51

sudecks atrophy | complex regional pain sx

Answer 51

type 1. no nn lesion type 2. nn lesion trauma, cns disorder, immobilization, MI patchy periarticular osteopaenia, ST swelling 》atrophy, joint space preserved, subcortical erosions/resorption

Question 52

hypertrophic OA

Answer 52

periosteal reaction of distal long bones with no lesion smooth periosteal thickening that becomes multilayered and extends from diaph 》metaph 》epiph. lung. plural (mesothelioma, pleural fibroma), Congenital cyanotic heart disease, lung abscess or mets, bronchogenic ca, IBD, lymphoma (GI and pulm), whipples, PBC.

Question 53

skeletal Tb | Tb dactylitis

Answer 53

expansive diaphyseal lesion (balloon like with int. septa) Associated ST swelling. no periosteal reaction bones distal to wrist and Tarsus involved cold abscess in adj ST with chronic sinus kids

Question 54

premature suture closure

Answer 54

``` rickets over shunting hypophosphataemia sickle cell and thalassemia dysplasias hyperthyroid Mucopolysaccharidosis (h and m) ```

Question 55

rickets mimics

Answer 55

biliary atresia hypophosphataemia chondrodysplasia metabolic bone disease

Question 56

cortical desmoid

Answer 56

posterior medial femoral epicondyle don't touch lesion pain hot on bone scan until involute

Question 57

Coraco-aceomial | acromio-clavicular

Answer 57

cc- <13mm | AC - <6mm or <4m asymmetry

Question 58

Tarsal coalition

Answer 58

talocalcaneal most common - C sign calcaneonavicular - ant eater. best seen oblique xray or MRI FS T2 can be cartilage, see bony oedema on MRI

Question 59

Gorlin disease

Answer 59

multiple odontogenic keratocysts, BCCs, bifide ribs and ST ca+

Question 60

pagets cw FD skull

Answer 60

``` both: sclerotic/lytic mixed diploic widening thick cortex - pagets involves both inner and outer but FD spares inner FD usually unilateral, pagets whole ```

Question 61

pagets CN palsy

Answer 61

8, 7, 2, 3 or peripheral nns also chordoma and FD cavernous sinus thrombus CN palsy in 3, 4, 6

Question 62

rib notching in coarctation

Answer 62

3 to 8 | costcervical trunk is 1 and 2

Question 63

floating teeth

Answer 63

hyperparathyroid cushing scleroderma

Question 64

tumoral calcinosis

Answer 64

hereditary periarticular ca+ hip, shoulder, elbow, foot, wrist amorphous, cloud like no erosion or ST mass associated

Question 65

Achondroplasia

Answer 65

skeletal dysplasia. rhizomelic short femur splayed 2,3 and 4 digit. trident frontal bossing skull big cranial vault with small foramen magnum posterior VB scallop in and progressive narrowing interped distance short pedicles and widened IV discs anteriorly flared ribs horizontal acetabulum with tombstone stumpy iliac wings and champaign glass small pelvis metaph flaring long bones rhizomelic metacarpals and metatarsals short and all same length

Question 66

Parsonage turner | quadrilateral space syndrome

Answer 66

brachial plexus neuritis increased T2 and dennervation rotator cuff mms ddx. disuse, suprascap notch mass (ganglion) axillary nn entrapment. teres minor or deltoid mm atrophy/fat infiltration/T2 high space-triceps long head, teres minor, major and humerus.

Question 67

thick skull

Answer 67

``` phenytoin shunted hydrocephalus acromegaly. enl frontal sinus and big jaw extramedullary haematopoiesis Pagets. inner and outer table Fiborous dysplasia. inner table spared ``` focal. osteoma, meningioma, mets

Question 68

Hair on end

Answer 68

Hemolytic Anaemia. Thalassemia (inner and put table gone), Sickle cell (assoc infection 2nd no spleen), hereditary spherocytosis Neoplasia. Haemangioma, meningioma, mets haemangiopericytoma Other. Cyanotic heart disease, severe iron deficiency kids pagets. cotton wool hyperparathyroid. salt and pepper kids. LCH (EG), Neoplasia, infection.