Questions and Answers
What are the basic projections of the knee (intercondylar fossa)?
What are the special projections of the knee (intercondylar fossa)?
Intercondylar fossa, femoral condyles, tibial plateaus, and intercondylar eminence should be demonstrated and are part of the?
clinical indications
Evidence of bony or cartilaginous pathology, osteochondral defects or narrowing of the joint space should be seen and are part of the?
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What are the loose bodies in the knee joint called?
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What is the minimum SID (source to image distance)?
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What is the IR size used?
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What is the KV range for the knee imaging?
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The IR should be oriented lengthwise for knee imaging.
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What tissues should be shielded during knee imaging?
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Recommended collimation should cover?
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How is the patient positioned for the Camp Coventry method?
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How is the knee positioned for the Camp Coventry?
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Center the IR to the _____
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CR is _____
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CR is perpendicular to the _____ (popliteal depression)
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Tube is angled _____, when the knee is flexed 40 degrees.
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Tube is angled _____, when the knee is flexed 50 degrees.
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The PA axial is also known as?
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The PA axial was first described _____
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The patient assumes a kneeling position on the radiographic table, which describes the?
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In _____, the Holmblad method was modified so that if the patient's condition is allowed, a standing position could be used.
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For the Holmblad method, the CR is?
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Where is the CR directed for the Holmblad method?
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What anatomy should be demonstrated with both the Camp Coventry and the Holmblad method?
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The intercondylar fossa should be _____ without _____
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Symmetric appearance of distal posterior femoral condyles are evidence of?
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Superimposition of half of fibular head by tibia is evidence of?
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Articular facets and intercondylar eminence well visualized without superimposition is evidence of?
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How is the part positioned?
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Where is the IR centered?
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From full extension, the knee is flexed _____ (Holmblad method)
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If the patient cannot flex the knee 60 to 70 degrees, what should they do (Holmblad method)?
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How is the patient positioned for the Holmblad method?
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How many positions can the patient be placed in for the Holmblad method?
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Optimal density is seen by?
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No motion is seen by?
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Why is the AP axial (Beclere method) not a preferred projection?
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Shielding for Beclere method?
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How is the patient positioned for the Beclere method?
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The knee is flexed _____ for the Beclere method.
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For the Beclere method, the IR is adjusted and centered to?
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What is placed under the IR as needed to ensure it is firmly against posterior thigh?
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The CR for the Beclere method is?
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The CR is perpendicular to the lower leg _____ degrees for the Beclere method.
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The CR is directed to a point _____
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Collimation for the Beclere method?
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Symmetric appearance of distal posterior femoral condyles is evidence of?
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Superimposition of half of fibular head by tibia is evidence of?
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Articular facets and intercondylar eminence well visualized without superimposition are evidence of?
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Study Notes
Knee - Intercondylar Fossa Projections
- Basic projections: PA axial (Camp Coventry method) and Holmblad method.
- Special projection: AP axial (Beclere method).
Clinical Indications
- Visualize intercondylar fossa, femoral condyles, tibial plateaus, and intercondylar eminence.
- Detect bony or cartilaginous pathology, osteochondrial defects, or joint space narrowing.
Terminology
- Loose bodies in knee joint referred to as "joint mice."
- Minimum SID (Source-to-Image Distance) is 40 inches.
- Image receptor (IR) size is 8 x 10 inches.
Exposure Parameters
- Kilovolt (KV) range for knee imaging is 70 to 85.
- IR should be positioned lengthwise.
- Shielding should cover radiosensitive tissues.
- Recommended collimation includes all four sides of the knee joint.
Positioning for Camp Coventry Method
- Patient lies prone with no rotation.
- Knee flexed 40 to 50 degrees, foot resting on a suitable device.
- Center the IR to the knee joint, considering the central ray (CR) angle.
- CR is perpendicular to the lower leg's long axis and centered to the knee joint.
- Tube angle adjustments: 40 degrees when knee is 40 degrees flexed, 50 degrees when flexed at 50 degrees.
History and Method Variations
- PA axial projection also known as the tunnel view.
- Holmblad method first described by Holmblad in 1937; modified in 1983 to allow a standing position if patient's condition permits.
CR and Visualization
- For Holmblad, CR is perpendicular to both IR and lower leg, directed at the midpopliteal crease.
- Aim to demonstrate intercondylar fossa, tibial plateaus, and knee joint space without superimposition by the patella.
Evidence of Proper Technique
- Symmetric distal posterior femoral condyles indicate no rotation.
- Superimposition of fibular head by tibia also confirms no rotation.
- Clear visualization of articular facets and intercondylar eminence signifies accurate positioning.
Optimal Imaging Conditions
- IR placed against the anterior surface of the knee and centered at the apex of the patella.
- For Holmblad method, knee flexed 60 to 70 degrees; if unable, patient should lean forward 20 to 30 degrees.
- For both methods, a maximum of three patient positions are possible.
Density and Clarity in Imaging
- Optimal density demonstrates soft tissue and patella outline clearly.
- No motion is indicated when trabecular markings are sharp and clear.
Beclere Method Specifics
- Not preferred due to increased object-to-image distance (OID) and potential exposure to gonads.
- Shielding technique involves covering pelvic area to mid-femur.
- Patient positioned supine with leg support during partial knee flexion of 40 to 45 degrees.
- For Beclere method, CR is perpendicular at a 40 to 45-degree angle cephalad, directed 1 inch distal to the apex of the patella.
Collimation and Visualization Evidence
- Collimation for Beclere method should encompass all four sides of the knee joint.
- Evidence of no rotation is again confirmed by symmetric appearance of distal femoral condyles, half of fibular head superimposition, and clear visibility of articular facets and intercondylar eminence.
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Description
Test your knowledge on the various projections of the knee, specifically focusing on the intercondylar fossa. This quiz covers both basic and special projection methods, including the Camp Coventry and Holmblad methods, as well as the Beclere method. Perfect for students learning radiographic techniques.