Test 3

What is the numerical breakdown of the components of the foot (singular)

1. 14 phalanges

2. 5 metatarsals

3. 7 tarsals

Total = 26 bones in the foot (27 for hand, one less bone in feet)

Where is a common site of sesamoid bones in the feet?

under the plantar surface of the head of the 1st metatarsal (common fracture site)

the calcaneus is the ______ and ______ bone in the foot

strongest and largest

what kind of joint is the ankle?

sellar/saddle

what angle is the tibial plateau in reference to the rest of the leg?

20 degrees posterior (angles downward)

What is the largest sesamoid bone in the body?

the patella

What angle is utilized for AP toes

10-15 degrees towards the calcaneus

How much of the metatarsals must be included on toes?

½

Where should you center for AP and Obl toes?

MTP joint on toe of interest

Which toes do you rotate medially, which toes do you rotate laterally for obl toes?

1. Medially - 1-3

2. Laterally - 4-5

What is the minimum inclusion of additional digits if you have an order for a single toe x-ray?

1 on each side at least (provides context)

Where do you center for lateral toes?

ip or proximal ip joint of interest

Tangential sesamoid (toes) projection

dorsiflex foot 15-20 degrees from vertical

can be prone or supine (preferred prone)

CR perpendicular to IR, direct to posterior aspect of 1st MTP joint

include 1-3 distal metatarsals

Angle AP foot

10 degrees POSTERIORLY (base of 3rd metatarsal)

Rotation Obl foot

30-40 degrees

Where do you direct the CR for lateral foot?

1. medial cuneiform OR

2. 3rd metatarsal base

How much of the ankle must be included on a foot?

1”

AP weight-bearing feet

15 degree posterior angle

between both feet at level of base of metatarsals

(best demonstrates lis franc injury)

Lateral weight-bearing foot

make sure pt stands on wood block

Plantodorsal calcaneus

direct to base of 3rd metatarsal

40 degree cephalad angle

demonstrates: open talocalcaneal joint, sustentaculum tali in profile

Lateral Calcaneus

dorsiflex foot

CR 1” inferior to medial malleolus

Ankle AP

supine with pillow

do not dorsiflex foot allow to rest naturally (per bontrager)

center mid malleoli

How much rotation is a mortise ankle

15-20 degrees

45 degree ankle obl

dorsiflex at least 80-85 degrees from IR

tib/fib joint open

lateral ankle

dorsiflex foot

include distal 1/3 of tib/fib

inversion = _______, Eversion = ________

1. varus

2. valgus

stress ankle (inversion/eversion)

1. physician must be present for stress test

2. use lead gloves if hand will be in beam

3. dorsiflex as near to right angle as much as possible

if using gravity instead of mechanical stress, pts ankle will be placed on a sponge where the ankle and foot overhangs in the desired rotation

must be fast and efficient as this is often painful for pts

AP/Lateral Tib/FIb

44-48” SID

use diagonal dimension of IR if necessary

ensure 1-2” of the ankle and knee joint is within the detector to ensure that both joint are actually caught on image

How much rotation is necessary for true AP knee

3-5 degrees internal rotation

centering for AP/Obl knee

½ “ distal to the patellar apex

How much flexion is required on a lateral knee? how much angle and what direction is the CR? Centering?

20-30 degree flexion, 5-7 degree cephalad angle, center 1” distal to the medial epicondyle

What is the method name of the PA Axial weightbearing bilateral knee projection (for intercondylar fossa, standing)

Rosenberg method

Rosenberg

40” SID
10 degree caudad angle

knees flexed 45 degrees

enter ½ ” below apex of patella

Camp Coventry is AP or PA?

PA

Camp Coventry

prone with 40-50 degree flexion of the knees

use sponge to support the legs in flexed position

match flexion with knee with CR (45 degree caudad angle, not specific in book)

Is the Homblad method AP or PA

PA

Homblad method

pt is kneeling with a 60-70 degree flexion of knees

can also be partially standing using a chair or the x-ray table to assist

CR perpendicular to IR

leaning pt forward 20-30 degrees results in desired amount of flexion in knees

Is the Béclere method AP or PA

AP

Béclere method

supine with detector under bent knees

knees flexed 40-45 degrees, CR directed 45 degrees cephalad

not preferred method due to OID produced in AP projections and distortion

PA patella

5 degree internal rotation for true AP

direct to “mid patellar region”

Lateral patella

flex knee 5-10 degrees , CR perpendicular to IR

direct to mid-patellofemoral joint

What is the technical term for a merchant/sunrise knee?

tangential axial knee

sunrise/skyline view

Merchant view knees

bilateral

40 degree flexion

CR 30 degrees caudal angle (from the horizontal plane)

IR should be placed approximately 1 foot below the knees

48-72” SID

Inferosuperior patella sunrise view

40-48 SID

40-45 degree knee flexion

pt is supine, NOT holding the detector (suspend via sandbags and tape)

CR 10-15 degrees from lower legs

Hughston method

pt is prone with knee flexed 50-60 degrees, use sheet to maintain position (not collimator box)

CR directed 45 degrees cephalad

Settegast method

40” SID

done PA (preferred) or AP sitting upright

PA - 90 degree flexion of knee minimum, CR 10-15 degrees from lower leg, pt prone

AP - pt upright, 90 degree flexion of knee and pt holding detector

Hobbs modification

48-50” SID

Superoinferior projection

48-50” SID

pt seated on chair

knees in acute flexion, x-ray shot downwards

What are the relevant angles of the proximal femur?

1. angle of neck to shaft - 125 degrees ±15 degrees

2. longitude of femur from vertical - 10 degrees

3. neck to body angle (side view) - 15-20 degrees

Because the neck to body angle is 15-20 degrees, what is the necessary positioning step to create a true AP image for proximal femur/pelvic imaging?

internal rotation of the legs by 15-20 degrees

What are significant features of the ischium?

1. tuberosity

2. spine

3. lesser/greater sciatic notch

what are significant features of the pubis?

superior/inferior ramus

is the true pelvis or false pelvis the birth canal?

true pelvis

what is the true pelvis also called?

the inlet/superior aperture

What is the outlet ?

area where the baby exits the pelvis

What is the space between the true pelvis (superior aperture/inlet) and the outlet of the pelvis (inferior aperture) called?

pelvic cavity

AP femur (mid-distal)

internally rotate by 5 degrees for true AP

lower margin of the IR is approx. 2” below the knee joint to make sure to include it

Lateral femur (mid-distal)

do not attempt when severe trauma has occurred

flex knee 45 degrees, roll pt towards affected leg to get femur parallel to IR

IR 2” below knee joint

do x table for severe trauma

Lateral femur (mid-prox.)

45 degree knee flexion

have pt roll back 15 degrees so superimposition does not occur

palpate ASIS and include at the level of the ASIS

AP Pelvis (bilat)

internally rotate feet 15-20 degrees

CR perpendicular midway btw ASIS and symphysis

suspend respiration

AP Frog (bilat)

abduct femora 40-45 from vertical

center at level of femoral heads (3” below ASIS)

suspend respiration

AP Axial outlet (Taylor method)

CR 20-35 degrees cephalad (males) 30-45 degrees cephalad (females)

1-2” distal to the superior border of the symphysis/greater trochanters

suspend respiration

AP Axial Inlet

CR 40 degrees caudad directed at level of ASIS

suspend respiration

Posterior Oblique Acetabulum (Judet method pelvis)

45 degree oblique

• Acetabulum

  • affected side down center 2” distal and medial to downside ASIS

  • affected side up center 2” directly distal to upside ASIS

• Pelvic ring

  • center 2” inferior from ASIS and 2” medial to upside ASIS

suspend respiration

PA Axial Oblique Acetabulum (Teufel method)

35-40 degrees anterior oblique

anatomy of interest on downside

CR centered 1” superior to level of the greater trochanter, 2” lateral from mid-sagittal plane

12 degree cephalad angle

suspend respiration

AP unilateral hip/prox. femur

rotate leg 15-20 degrees internally

center perpendicular to femoral neck (1-2” medial, 2-4” distal to ASIS)

suspend respiration

Axiolateral inferosuperior hip/prox. femur (Danielus-Miller method)

flex/elevate unaffected leg

place IR in crease above crest, parallel to femoral neck —> CR directed perpendicular to IR and femoral neck

elevate pelvis 1-2” if possible

suspend respiration

Mod. Axiolateral hip/prox. femur (Clements-Nakyama method)

bottom of IR 2” below table top

tilt IR 15 degrees from vertical

CR angled mediolaterally towards femoral neck, posteriorly 15-20 degrees from horizontal

AP Axial SI Joints

CR angled 30-35 degrees cephalad (steeper for women, less for men), centering 2” below level of ASIS

alternative PA = 30-35 degrees caudad at level of crest or L4ish

suspend respiration

Posterior Oblique SI joints (LPO/RPO)

pt body rotated 25-30 degrees with SIDE OF INTEREST elevated, flex elevated knee for support and use wedge sponge

center CR perpendicular 1” medial to upside ASIS

suspend respiration