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Flashcards in LE Deck (57)
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Knee AP View

Pt supine with knee fully extended and leg in neutral
Beam directed vertically 5-7 degrees slightly cephalic
Limitation: superimposed patella


Knee Lateral View

Pt lays on involved side with 25-30 degrees of knee flexion
Beam directed at medial knee joint 5-7 degrees cephalad
Best for patella femoral relationship


Relationship of patellar ligament length (PL) to patella length (L)

PL=L +/- 20%


Tunnel (Notch) View (Knee)

Pt prone with knee flexed to 40 degrees
Beam projected caudally at 40 degrees from vertical
Demonstrates posterior aspect of femoral condyles, intercondylar notch, intercondylar eminence, medial and lateral tibial spine


Potential increased risk of ACL tear

Females have more of an 'A' intercondylar notch while males have more of an 'H' notch


Sunrise View (Knee)

Pt. prone with knee flexed 115 degrees
Beam directed at patella 15 degrees cephalad
Demonstrates femoropatellar joint compartment well


What is the purpose of deep knee flexion with sunrise view?

to depress the patella deeply within the intercondylar fossa


Disadvantages of Sunrise View

Articular surfaces of femoropatellar joint not well viewed
Subtle subluxations may not be detected
Position tolerance


Axial (Merchant) View (Knee)

Pt supine with knee flexed 45 degrees
Beam directed caudally through patella at 60 degrees from vertical
Demonstrates Articular facets of the patella and femur, sulcus and congruence angle


Congruence angle

Normal: -6 degrees
Greater than 16 degrees associated with patellofemoral disorders
Bisect sulcus angle, draw 2nd line from lowest point of articular ridge of patella to deepest point of sulcus


Sulcus Angle

Normal: 138 degrees
Formed by lines extending from deepest point of intercondylar sulcus to the top of the femoral condyles


AP Demonstration (Knee)

Medial and lateral joint compartments
Varus and valgus deformities
Fx of femoral condyles, tibial plateus, tibial spines, proximal fibula,
Osteochondral fx
Osteochondral dissecans (late stage)
Spntaneous osteonecrosis
Pellegrinini-Stieda lesion


FBI Sign

Fat Blood Interface aka Lipohemarthrosis: Blood and bone marrow fat enter the joint creating layering on radiograph
Indicates: Intraarticular Fx


Sinding-Larsen-Johansson Disease

Fragmentation of lower pole of the patella and significant soft tissue swelling associated with calcification and ossifications of the patellar ligament


Osgood-Schlatter Disease

Avulsed tibial tuberosity
Soft tissue swelling
Tx: activity modification lower impact and counterforce braces, will heal itself with maturation and time


Osteochondral Fx

Shearing/ rotary forces applied to the articular surface of the femur result in detachment fragment of articular cartilage


Types of meniscus tears

Peripheral detachment
Peripheral Tear
Cleavage Tear
Simple Vertical Tear
Bucket-Handle Tear
Oblique Tear


Ankle AP View

Pt supine with foot in neutral
Beam directed vertically at midpoint between malleoli
Identifies distal tibia and fibula
Fibular Malleolus Longer than Tibial Malleolus


Ankle AP View Limitations

Overlap of distal fibula and lateral tibia obstructs view of tibiofibular syndesmosis


Mortise View (Ankle)

10 degrees of IR of the ankle eliminates overlap of medial distal fibula for better view of syndesmotic space


Ankle Lateral View

Pt lays on involved side
Beam directed vertically to the medial malleolus
Demonstrates anterior aspect of the distal tibia and posterior lip (3rd malleolus) and Fx oriented in the coronal plane


What imaging modality will demonstrate meniscal injury



Ottawa Knee Rules

Age 55+
Tenderness at head of fibula or isolated tenderness of patella
Inability to flex knee to 90 degrees
Inability to weight bear 4 steps
ARE valid under the age of 18
Sensitivity: 98-100%
Specificity: Low


Segond Fx and what is typically injured with it



Internal Oblique View (Ankle)

Pt in supine with leg and foot in 35 degrees of IR. Neutral PF/DF (90 degrees to leg).
Beam Directed at lateral malleolus
Demonstrates: Medial and lateral malleoli
Tibial Plafond
*Dome of the Talus
Tibiotalar joint
Tibiofibular syndesmosis


Inversion Stress View (Ankle)

Pt in supine with foot fixed in device. Pressure plate is positoned 2 cm above ankle joint and applies varus stress adducting the heel
Degree of talar tilt is measures by tibial plafond and dome of the talus. (bilateral comparison)
Normal is 20 degrees


Anterior-Draw Stress (Ankle)

Pt on involved side with foot in device. Pressure plate positioned anteriorly 2 cm above ankle and applies posterior stress to shin with heel fixed.
Measure separation btwn Talus and Distal Tibia
0-5 mm Normal
5-10 mm Normal/Abnormal
>10 Abnormal


Foot AP View (Dorsoplantar)

Pt in supine with knee flexed and foot flat on film.
Beam directed vertically to the base of the *first metatarsal bone
Demonstrates metatarsal bones and phalanges
1st metatarsal angle


1st Metatarsal Angle

Quantifies the amount of metatarsus primus varus associated with hallux valgus
Normal angle 5-10 degrees


Foot Lateral View

Pt on involved side
Beam directed vertically to midtarsus
Demonstrates: Bursal projection
Posterior, Medial, Anterior Tuberosities
Anterosuperior spine of calcaneous
Posterior facet of subtalar joint
Sustenaculum tali
Boehler Angle
Calcaneal pitch