imaging final exam

osteochondritis dessicans (elbow)

- most common in capitulum
- separation of cartilage segment and subchondral bone from articular surface
- common in adolescent athletes
- USE MRI

epicondylitis

- medial = flexors
- lateral = extensors
- diagnose with US

monteggia fx of elbow

proximal 1/3 of ulna w dislocation of radial head

nightstick fracture of elbow

fracture of ulnar shaft

galeazzi fx of elbow

fx of distal 1/3 radial shaft and distal radioulnar joint dislocation

proximal ulnar fx

3 types
- type 1: proximal 1/3 olecranon
- type 2: middle 1/3 olecranon (most common)
- type 3: distal 1/3 olecranon (closer to ulnar shaft)

radial head fracture

4 types
- type 1: undisplaced
- type 2: marginal fx w displacement
- type 3: comminuted fx
- type 4: radial head fx and dislocation

distal humerus fracture

- supracondylar fx (above condyles)
- transcondylar fx (transverse line through condyles)
- intercondylar fx (fx IN BETWEEN condyles, vertical line)
- condylar fracture (condyles broken off)
- articular fx (fx of articular surfaces)
- epicondylar fx (avulsion fx)

what can u see in coronal plane MRI/CT of elbow

- medial and lateral collateral ligaments
- common flexor and extensor tendons

what can you see in saggital plane MRI/CT elbow

- radial head
- humerradial joint
- humeroulnar jt

what can you see in axial plane MRI/CT elbow

- biceps tendon
- triceps tendon
- brachial artery
- radial/ulnar N

AP elbow radiograph elbow

anatomical position

lateral elbow radiograph elbow

articulations with humerus

oblique IR radiograph elbow

medial epicondyle

oblique ER radiograph elbow

radial head articulation with humerus

AP forearm radiograph

more focus on radius and ulna

lateral forearm radiograph

ulnar head at wrist
radial head at elbow

labrum tears

image with MRA
- associated with dislocations, 3 types
- avulsion off glenoid rim (bankart fx)
- terar in substance of labrum
- SLAP lesion /biceps tendon

rotator cuff tears

use MRI to image
- can be complete or partial
- treatment depends on degree of tear
- surgery when >3 cm

AC joint laxity/sprain

image with AC radiograph with/without weights to image
- grade 1: mild sprain AC
- grade 2: AC torn and CC stretched
- grade 3: AC and CC torn

shoulder trauma neer classification

1 part: non displaced
2 part: displaced (2 pieces)
3 part: displaced (3 pieces)
4 part: displaced (4 pieces)

GH dislocation

mostly anterior (aB and ER)
- can cause hill sachs lesion (compression fx posteriolateral humeral head)
- bankart elsion (avulsion fx ant/inf labrum)

scapular fx

very rare
- caused by direct blow

clavicle fx

- classified by location (middle 1/3 most fragile)
- can be birth related
- seatbelt in car accident
- treated by immobilizing
- complications: malunion, nerve/vascular concern

proximal humerus fx

- humeral head (anatomical neck)
- greater tuberosity (supra, infra, teres minor)
- lesser tuberosity (subscap)
- shaft at surgical neck

what imaging should you use for proximal humerus fx

AP scapular and y-view
- treatment depends on stability and displacement

shoulder AP ER radiograph

see greater tuberosity

shoulder AP IR radiographs

see lesser tuberosity

shoulder axillary view radiograph

see acromion, glenoid, and coracoid

shoulder anterior oblique (y-view) radiograph

still see humerus and lateral scap

AP with and without stress (AC stress) radiograph

separates AC joint slightly

AP scapular view radiograph

clearest view of scapula

lateral scapular view radiograph

space between scapula and ribs

when should u take an MRI of the shoulder

- muscle/tendon injury
- long head of biceps disorders
- labral injuries
- ligament injuries

axial plane MRI/CT of shoulder

see biceps tendon and labrum

saggital plane MRI/CT of shoulder

- supra/infraspinatus
- acromion
- coracoacromial site

coronal plane MRI/CT of shoulder

see GH joint and AC joint

types of foot fractures

- talar fx (poor blood supply, concern for necrosis)
- calcaneal fx (long rehab process)
- midfoot fx (lisfranc or navicular)
- forefoot fx (metatarsals or phalanges)

ankle fx

- unimalleolar
- bimalleolar
- trimalleolar (malleoli and posterior rim tibia)

foot deformities

- hallux valgus (1st met deviates medially >10 degrees)
- pes cavus (high arch)
- pes planus (flat foot)
- talipes equinovarus (clubfoot)

talometatarsal angle

intersection of midshaft 1st met and talus (use WB radiograph to view)
- normal angle = 0 deg

tendon pathologies of the foot

use MRI to image
- achilles tendon
- tendons of fibularis longus/brecis after inversion stress injury

ankle sprain

inversion most common
- usually dont need imaging, can be used for avulsions due to pull of ligament

ottowa foot rules

tenderness at navicular or base of 5th met
- inability to WB

ottowa ankle rules

tenderness of medial or lateral malleoli
- inability to WB

AP foot radiograph

lateral foot radiograph

oblique foot radiograph

AP ankle radiograph

AP oblique/mortise ankle radiograph

lateral ankle radiograph

stress view ankle radiograph

for alignment/positioning
- use eversion/inversion

patellofemoral dislocations

acute or chronic
- medial/lateral dislocation = tangential view
- superior/inferior dislocation = lateral view

patella fx

- transverse (displaced or nondisplaced, use lateral x-ray to see)
- vertical (displaced or non displaced)
- comminuted (displaced or nondisplaced)
- avulsion

proximal tibial fx

6 types
1: wedge/split of lateral aspect of plateau
2: lateral wedge or split fx
3: pure compression fx lateral plateau
4: involves medial plateau
5: split fx of both condyles
6: complete bicondylar fx

distal femur fx

- supracondylar (nondisplaced, impacted, displaced, comminuted)
- condylar (fx at condyle)
- intercondylar (between condyles)

meniscal tears

use MRI fofr imaging
- soft tissues

knee cartilage injuries

- osteochondral fx (young atheltes)
- osteochondritis dessicans
- spontanous osteonecrosis (older adults)

rules for knee radiograph

- joint effusion after direct blow/fall
- mobility to walk without limping
- palpable tenderness over patella or fibular head
- inability to flex knee to 90 deg
- age >55

knee fxs

- distal femur fracture
- patellar fracture
- patellar dislocations
- proximal tibial fx

DJD/OA of the knee

- reduction in joint space
- sclerosis of subchondral bone
- osteophytes at joint margin
- subchondral cysts
- could have varus or valgus deformities

osgood schlatter disease

- enlarged tibial tubercle
- repetitive trauma at distal tendon attachment
- common in adolescent boys
- USE LATERAL RADIOGRAPH

imaging for ligament injuries in the knee

- cruciate ligament tears: MRI
- collateral ligament tears: stress x-ray
- avulsion fx: x-ray

knee MRI/CT axial view

looks like tangential x-ray
- see tibial plateau

knee MRI/CT saggital view

looks like lateral radiograph

knee MRI/CT coronal view

looks like AP radiograph

when should you use an MRI for knee

- meniscus lesions
- ligament injuries
- soft tissue injuries
- osteochondral abnormalities

tangential knee radiograph

see patella and distal femur
- use if alignment slightly off
- use for vertical fx of patella

PA knee radiograph

see intercondylar eminence

lateral knee radiograph

can see patella tracking superiorly/inferiorly
- alta = high
- baja = low
- use for transverse fx patella

AP knee radiograph

- distal femur
- proximal tibia and fibula
- no patella or tibial plateau

FAI

femoroacetabular impingement
- cam: outgrowth on femoral head
- pincer: outgrowth on acetabulum

slipped capital femoral epiphysis

- femoral epiphysis slips posteriorly
- blurring of physis on AP pelvis view
- use lateral frog view

Legg-Calve-Perthes Disease

epiphyseal ischemic necrosis at femoral head
- 3-12
- femoral head looks squished

trochanteric fx

fx of greater or lesser trochanters
- typically avulsion
- AP hip (greater) or frog leg (lesser)

subtrochanteric fx

- proximal femur fx
- elderly or young pt
- image using AP hip
- treat w cephalomedullary nail fixation

intertrochanteric fx

extracapsular
- seen w AP hip view
- compare w AP pelvis
- treat w ORIF

femoral neck fx

intracapsular
- increased risk for AVN
- AP radiograph
- treat w ORIF or arthroplasty

acetabular fx

due to femoral head driving into acetabulum
- REQUIRES CT SCAN bc of bony overlap

hip fx

high rates of morbidity and mortality
- femoral neck
- intertrochanteric
- trochanteric

frog leg radiograph

FABER
- LE in ER
- better view of trochanters

DJD/OA hip

- joint space narrowing
- sclerotic subchondral bone
- osteophyte at joint margins

RA hip

- symmetrical joint space narrowing
- loss of bone density
- joint effusion

AVN hip

- femoral neck fractures increase risk
- preserved joint space
- MRI detects changes in bone marrow, bone tumors, stress fx and AVN
- CRESCENT SIGN

arthography hip

evaluates carticalge, labrum, and presence of FAI

hip MRI/CT coronal view

- bilateral comparison hip joints
- acetabulum
- femoral head neck and shaft
- SI joints, sacrum, greater and lesser trochanter

hip MRI/CT saggital view

- acetabular rood
- iliopsoas muscle
- SI joints
- pubic symphysis

hip MRI/CT axial view

- femoral head in acetabular fossa
- sacrum
- greater and lesser trochanter