Positioning Exam Chapter 6 - Foot, Ankle, and Calcaneus

What CR angulation is required for the AP oblique projection of the foot?

CR is perpendicular, no angulation

Extending the ankle joint or pointing the foot and toes downward is called?

Plantar flexion

To properly visualize the joint spaces with the AP projection of the foot, the CR must be:

Perpendicular to the metatarsals

What is the purpose for the AP stress views of the ankle?

Demonstrate possible joint separations

How much rotation from an AP of the ankle will produce a mortise view

15-20 degrees

Where is the CR placed for a mediolateral projection of the calcaneus?

1 in. inferior to the medial malleolus

How much CR angulation to the long axis of the foot is required for the platodorsal axial projection of the calcaneus

40 degrees

If a patient is unable to assume the positions recommended for demonstration of the sesamoid bones of the foot, what projection may be used instead?

Lateral of the 1st digit in dorsiflexion

Which metatarsals are free of superimposition on a correctly obliqued foot>

Third, fourth, fifth

The CR is directed to the base of the _____________ metatarsal for AP and oblique feet projections.

Third

Which metatarsal is most commonly fractured?

Fifth

For an axial projection of the calcaneus, the plantar surface of the foot should be ______________ in relationship to the film.

Perpendicular

Which position of the foot will be best demonstrate the lateral cuneiform?

AP oblique with medial rotation

Which joint surfaces of the ankle joint are open with a true AP projection of the ankle? (Spaces between the tibia, fibula, and talus)

Medial and superior

A radiograph of a mortise view of the ankle reveals that the lateral malleolus is slightly superimposed over the talus and the lateral joint space is not open. What is the most likely error?

Insufficient medial rotation of foot

What tube angle is recommended for an AP projection of the feet?

10 degrees toward the calcaneus

Which medical professional is responsible for moving the ankle for stress projections?

Physician

The sesamoid bones of the foot lie posterior to the __________ metatarsal.

First

The recommended kVP ranges for radiography of the toes, foot, or ankle are:

55-65

True or False? Standing radiographs of the foot are done to evaluate the arches of the foot.

True

True or False? The medial malleolus lies more inferior to the lateral malleolus.

False

True or False? The technologist should always try to separate the uninjured toes away from the injured toe when taking a lateral projection.

True

True or False? The foot should be obliqued laterally when the fourth digit is the digit of interest.

True

True or False? The correctly positioned AP mortise ankle will frequently also demonstrate a fracture of the base of the 5th metatarsal if present.

True

Bonus: Explain the difference between an AP oblique and an AP mortise view of the ankle. Make sure to include the differences in obliquity (if there is any) and what structure would be more visible on each.

Pathology involving mortise and 5th tuberosity for mortise shot. Pathology involving distal tibia and fibula joint, distal fibula and lateral malleolus and base of 5th