Foot & HW 1

Failure to rotate the patient's entire leg and foot when obtaining an AP oblique ankle might result in: Repeat radiograph Poorly positioned leg Poorly demonstrated anatomical structures Well defined ankle mortise

1, 2, and 3

When radiographing the lower leg, what structures should be clearly demonstrated? Ankle joint Knee joint Tarso metatarsal joint Bony trabeculae

1, 2, and 4

When taking an AP oblique of the toes how should the foot be rotated?

1-2 toes medially, 4-5 toes laterally, third ormiddle toe doesn't matter

CR for AP axial

10 degrees towards heel entering base at 3rd metatarsal

Film size for AP, AP axial, medial oblique foot

10x12 or 11x14 LW

How many phalanges are in the foot?

14

Direction of CR for AP toes when joint spaces need to be seen

15 degrees posteriorly through 3rd MCP or elevate the foot on a 15 degree foam wedge with no angulation on CR

The joint between the proximal and distal phalanges

1st interphalangeal joint

Proximally the metatarsals articulate with

1st, 2nd, 3rd cuneiform and cuboid

How many bones are in the foot and ankle?

26

In the AP oblique projection with medial rotation of the foot, the plantar surface surface of the foot should form an angle of____________ with the cassette.

30 degrees

In order to BEST demonstrate the distal ends of the tibia and fibula, how much should the leg and foot be rotated when performing the AP oblique ankle with medial rotation?

45 degrees

When radiographing a foot the central ray is directed 10 degrees posterior (towards the os calcis) and enters the base of the 3rd metatarsal. What image is obtained?

AP Axial of the foot

On the calcaneus superiorly there are 3 _______, called anterior, middle, and posterior that join with the talus.

Articular facets

Alternative term for talus

Astragalus

Where the Achilles' tendon attaches

Calcaneal posterior tuberosity

The largest of the tarsals

Calcaneous

Heel bone

Calcaneus

Which of the following bones articulate with the talus inferiorly?

Calcaneus

When is the lateromedial projection of the ankle recommended? Erect for weight-bearing ankle Cross-table for trauma For patient comfort It is not recommended

Cross-table for trauma

Midfoot

Cuneiforms, navicular, and cuboid

In order to best demonstrate the joint spaces when radiographing toes in the AP projection, how should the CR be directed and where should it enter?

Direct the CR 15 degrees posteriorly entering the 3rd MTP with the toes resting directly on the cassette Direct the CR perpendicular entering the 3rd MTP if the toes are placed on a 15 degree angle sponge.

(T/F)When demonstrating the 1st and 2nd toes in the oblique position, the foot should be obliqued laterally.

False

Purpose of AP foot

Foreign body

Cuneiforms

Identified medial to lateral; anterior to navicular and posterior to 1st, 2nd, 3rd metatarsals

Foot AP oblique with medial rotation position structures demo'd

Interspaces (between cuboid & calcaneus/between cuboid & 4th and 5th metatarsals/ between talus & navicular/ between cuboid & lateral cuneiform) Tuberosity of the 5th metatarsal Cuboid shown in profile Sinus tarsi well shown

The Method used to demonstrate congenital club foot is known as:

Kite

When performing the mediolateral projection of the foot, which side of the foot will the technologist instruct the patient to place on the IR?

Lateral side

Navilicular

Lies on medial aspect/ between talus posteriorly/ between cuneiforms anteriorly

Which projections is most commonly used in clinics to obtain a lateral image of the foot?

Mediolateral

Structures demonstrated for AP and AP axial

Metatarsals, phalanges, and tarsals anteriorly to talus

eval criteria for AP oblique with medial rotation

No superimposition of bases 3-5th metatarsals Bases of the 1st and 2nd metatarsals superimposed Bases of 4th and 5th clearly demonstrated Sinus tarsi & tuberosity of 5th metatarsal

Alternative term for calcaneus

Os calcis

Foot AP eval criteria

Overlap of 2-5 metatarsal bases, no rotation

Foot AP axial eval criteria

Overlap of 2-5 metatarsal bases, no rotation, open joint spaces

Are the IP joint spaces better seen on AP or PA toes and why?

PA, less beam divergence

CR for all foot positions EXCEPT LATERAL:

Perpendicular to IR entering base of 3rd metatarsal

When radiographing the foot in the AP projection for possible localization of a foreign body, the CR should be directed:

Perpendicular, entering the base of the 3rd metatarsal

How should the CR be directed and where should it enter for the AP oblique projection with medial rotation of a foot?

Perpendicular, to the base of the 3rd metatarsal

Forefoot

Phalanges and metatarsals

Which of the following would NOT be demonstrated in the axial plantodorsal projection of the calcaneus? Answers: Subtalar joint Cuboid calcaneal joint space Sustaculum tali Sinus tarsi

Sustaculum tali

Shelf like process on the medial body of the calcaneus

Sustentaculum tali

The shelf-like overhang structure on the medial aspect of the calcaneus is the ___________.

Sustentaculum tali

Congenital clubfoot is also known as ________ .

Talipes equinovarus

2nd largest and most superior tarsal bone

Talus

Articulates with the tibia, fibula, calcaneous, and navicular

Talus

The ankle mortise is formed by:

Talus Fibula Tibia

Hindfoot

Talus and calcaneus

When performing an AP oblique ankle, the technologist rotates the patients entire leg and foot together 15-20 degrees. What will be the result of this image?

The Ankle Mortise joint will be best demonstrated

The CR is directed 40 degrees cephalic and enters at the base of the 3rd metatarsal, what image is produced?

The axial plantodorsal projection of the calcaneus

f you were requested to do an AP oblique projection of a foot in lateral rotation, which of the following structures would be demonstrated?

The interspaces between the medial and intermediate cuneiforms AND the interspaces between the 1st and 2nd metatarsals

While performing the AP oblique foot with medial rotation the technologist rotates the foot so the plantar surface forms a 45 degree angle to the plane of the IR. How will this visually effect the image?

The lateral cuneiform will be superimposed over the other cuneiforms.

What type of joint is distal between the proximal row of phalanges and metatarsals

The metatarsophalangeal joints

What type of joint is proximal between the metatarsals and tarsals

The tarsometatarsal joints (TMT)

The medial malleolus is located on the:

Tibia

Which bones form the ankle

Tibia and talus forming the talotibial joint

What is the purpose of dorsiflexing the foot when performing the lateral ankle?

To prevent lateral rotation of the ankle

(T/F) The routine projections for a lower leg consist of AP and Lateral

True

(T/F) When demonstrating the 4th and 5th toes in the oblique position ,the foot should be obliqued medially.

True

the lateromedial demonstates

a true lateral of the foot

eval criteria AP oblique foot with lateral rotation

all necessary anatomy may include portions of talus & calcaneus proper rotation (1st and 2nd bases free from superimposition, minimal superimposition between medial and intermediate cuneiforms, navicular seen with less foreshortening than medial rotation)

CR for calcaneus axial plantodorsal

angled 40 degrees cephalad or to the long axis of the foot; entering at base of 3rd metatarsal

structures demo'd lateral calcaneus

ankle joint and calcaneus in profile

structures demo'd in mediolateral kite method

anterior talar subluxation and degree of plantar flexion

structures demonstrated in axial plantodorsal

axial projection of calcaneus (os calcis); including calcaneal tuberosity and sustentaculum tali

where is the sinus tarsi located?

between the calcaneous and talus

eval criteria for lateral calcaneus

calcaneal tuberosity, sustenaculum tali, sinus tarsi, ankle joint

eval criteria for axial plantodorsal

calcaneus and subtalar joint, calcaneal tuberosity, trochlear process, lateral process, sustentaculum tali, talocalcaneal joint, cuboid calcaneal joint

structures demo'd for lateral mediolateral foot

entire foot in profile, distal ends of tibia & fibula, ankle joint

purpose of axial plantodorsal?

for demonstration of fxs and spurs

foot AP oblique with lateral rotation structures demo'd

interspaces between 1st and 2nd metatarsals, 1st and 2nd cuneiforms Navicular clearly demonstrated

why is the lateromedial not done routinely

it's uncomfortable for the patient

part position of lateral calcaneus

lie on affected size, place calcaneus on IR and doriflex foot

which side of the patient is placed on the IR for lateromedial

medial side

what type of projection is the kite method?

mediolateral

eval criteria for lateral mediolateral foot

metatarsals nearly superimposed, sustentaculum tali, sinus tarsi, fibula overlapping posterior part of tibia, distal tibia & fibula, talotibial joint

position of part and patient for mediolateral kite method

patient: lateral on side, flex uppermost limb bend knee and draw it forward part: place foam under knee (on leg of foot being imaged) to prevent angling of foot and ensure lateral position

CR lateral calcaneus

perpendicular to mid calcaneus (os calcis)

CR for kite method

perpendicular to midtarsal area

part position for mediolateral foot

place injured foot on lateral side, dorsiflex foot (foot should be 90 degrees to the leg), plantar surface parallel to long axis of IR

what is the function of the longitudinal arch of the foot?

shock absorber, distributes weight, and permits smooth walking

which joint space is not always open in the toe oblique?

the 1st MCP joint

which foot position shows the cuboid in profile?

the AP oblique projection with medial rotation

hallux valgus

the angulation of the 1st toe towards the other toes