Foot 2 dorsi plantar oblique Flashcards
What equipment is required for the dorsi-plantar oblique projection?
24 x 30 cm image receptor (split into two parts),
lead rubber sheet,
sandbag,
lead protective waist apron.
How should the patient be positioned for the dorsi-plantar oblique projection?
- Seat the patient with the knee of the affected side flexed enough to have the plantar surface of the foot rest on the X-ray couch.
- Rotate the leg medially until the plantar surface forms a 30° angle with the image receptor.
- Place the affected foot on the unexposed half of the image receptor parallel with its long axis
- Center the image receptor to the midline of the foot at the level of the base of the third metatarsal.
Why is the rotated 30 degrees instead of 45 when doing an x-ray examination of the foot Ap oblique.
When the leg is rotated 30 degrees, the lateral cuneiforms don’t superimpose other cuneiforms .
What is the centering point for the dorsi-plantar oblique projection?
Over the cuboid-navicular joint.
What is the direction of the central ray for the dorsi-plantar oblique projection?
Vertical beam 90° to image receptor.
Evaluation criteria for Dorsiplantar oblique of foot
- Evidence of proper collimation
- Entire foot, from toes to heel
- Proper rotation of foot
- Navicular, lateral cuneiform, and cuboid with less
superimposition than in the AP projection - Tuberosity of the fifth metatarsal
- Lateral tasometatarsal and intertarsal joints
- Sinus tarsi
- Soft tissue and bony trabecular detail
What equipment is required for the axial (plantodorsal) projection?
8 x 24 cm image receptor (split into half), sheet of lead rubber, length of bandage or strong tape, sandbag, lead protective waist apron.
What are the clinical indications for an axial (plantodorsal) projection of the calcaneus
Pathologies or fractures with medial or lateral displacement.
How should the patient be positioned for the axial (plantodorsal) projection?
Seat the patient on the X-ray couch with legs extended and unaffected leg abducted. Dorsiflex the ankle and place the heel on the image receptor. Ask the patient to hold the ankle in dorsiflexion with the bandage or tape and immobilize the lower leg.
What is the centering point for the axial (plantodorsal) projection?
Base of the third metatarsal.
What is the direction of the central ray for the axial (plantodorsal) projection?
Angle the central ray 40° cephalad from the long axis of the foot.
What are the evaluation criteria for an axial (plantodorsal) image of the calcaneus?
Proper collimation, calcaneus and subtalar joint clearly shown, no rotation of the calcaneus, similar brightness in anterior and posterior portions, and clear soft tissue and bony trabecular detail.
What equipment is required for the lateral projection of the calcaneus?
18 x 24 cm image receptor (split into half), sheet of lead rubber, length of bandage or strong tape, sandbag, lead protective waist apron.
How should the patient be positioned for the lateral projection of the calcaneus?
Lie the patient on the affected side with hip and knee flexed.
Rest the unaffected leg in front of or behind the affected leg.
Raise the knee of the affected leg on a pad and place the heel under examination on the image receptor in true lateral position.
What is the centering point for the lateral projection of the calcaneus?
2.5 cm inferior to the medial malleolus.
