W6- Ankle/Foot Reviewing Radiologic Images Flashcards
What are some common views utilized to view the ankle? (4)
- AP
- AP Oblique (Mortise)
- Lateral
- Stress Views (Anterior Drawer Stress Test, Inversion/Eversion Stress Test)
What are some common views utilized to view the foot? (3)
- AP
- Lateral
- Oblique
What are some things we can see with an AP view of the ankle? (5)
- overlap of fibula and tibia
- medial talar dome (can’t see mortise joint well)
- lateral/medial malleolus
- indiscernible tarsal bones
- medial talar dome articulation with medial malleolus to create space for mortise joint
AP Ankle:
- Can we see the mortise joint well in the AP view?
- Does the lateral or medial malleolus extend more distal?
- Are we able to distinguish tarsals in this view?
- What may excessive space between the tibia and fibula be indicative of?
- What may talar dome malposition be indicative of?
- No
- lateral malleolus
- No
- Consistent with syndesmotic ankle sprain
- Fx or dislocation of foot/ankle
What view is utilized to see the mortise joint?
AP Oblique (Mortise)
What are some things we can see with an AP Oblique view of the ankle? (4)
- mortise joint (talar dome, medial malleolus)
- distance between tibia and fibula
- talonavicular joint line
- metatarsals
What are some things we can see with a lateral view of the ankle?
- superimposition of tibia and fibula
- subtalar joint (talus/calcaneus)
- talonavicular joint (smooth joint lines)
- navicular and medial cuneiform
- superimposed metatarsals
What should we be concerned of when there is a fracture of the calcaneus due to high impact forces?
HIGH ASSOCIATION of THORACOLUMBAR COMPRESSION FRACTURES
What is the purpose of performing inversion/eversion stress views of the ankle? What could it indicate?
- To determine if there is excessive motion.
- Could indicate fracture, instability, ligamentous integrity
What is the purpose of performing anterior drawer stress view of the ankle? What could it indicate?
- Lateral view used to assess excessive anterior translation when anterior force placed on ankle.
- Could indicate ATFL tear/rupture.
What are some things we can see with an AP view of the foot? (4)
- talonavicular joint
- transverse tarsal joint
- navicular/cuboid/cuneiforms/metatarsal
- proximal/intermediate/distal phalanges
- What is the 1st intermetatarsal angle?
- What could it be indicative of?
- Line bisecting 1st and 2nd metatarsal.
- Fx, dislocation, malposition
What are some things we can see with a lateral view of the ankle? (4)
- talonavicular joint
- navicular/medial cuneiform joint
- calcaneal inclination
- tarsal sinus
What is calcaneal inclination?
= line from calcaneus inferior surface to bottom of metatarsal joints (if excessive (~50 degrees) pes cavus, normal = 20-30)
What are some things we can see with an oblique view of the foot?
- metatarsals
- sesamoid bones
- navicular/cuboid
- lateral cuneiform
Where are foot sesamoid bones located?
flexor hallicus tendons
-What are typically the first studies done for suspected bony and soft tissue abnormalities of the foot/ankle?
- When would we use USI?
- When would we use MRI?
- When would we use CT?
- When would we use bone scan?
-X-rays
- Superficial soft tissue abnormalities.
- Commonly for defining soft tissue injury, stress fractures, osteomyelitis.
- Commonly for defining complex fractures, osteochondral lesions, tarsal coalition.
- Screening the skeleton for metastases, local CRPS, potential occult fractures.
What is the difference when it comes to advanced imaging studies of the foot vs ankle?
Ankle = Done in regular planes. -Foot = Planes oriented at oblique angles to see foot structures easily with slices.
CT General Indications. (7)
- FRACTURE/DISLOCATION/ALIGNMENT/DISPLACEMENT
- TARSAL COALITION
- Severe trauma
- Loose bodies within joint
- Osteochondral lesions
- Pre-op planning
- Health conditions typically viewed with MRI, if MRI is contraindicated
MRI General Indications. (14)
- OSTEOCHONDRAL LESIONS
- Staging Disease (FRACTURES, STRESS FRACTURES)
- Tendon disorders: Achilles, posterior tibial, fibulari
- Ligament abnormalities: Medial & lateral ankle, syndesmotic
- Impingement syndromes
- Articular cartilage abnormalities
- Neurologic conditions
- Loose bodies
- Plantar fasciopathy
- Synovial disorders
- Marrow abnormalities
- Neoplasm
- Infections
- Congenital/ developmental conditions
