PA Axial Intercondylar Fossa Camp-Coventry

Lower Extremity positioning

PA Axial Intercondylar Fossa Camp-Coventry is a radiography positioning projection of the Lower Extremity. Prone, knee flexed 40-50 degrees, CR 40-50 degrees caudad. SID 40". The centering point is located intercondylar notch with patient prone and knee flexed 40-50 degrees.. The central ray is 40-50 degrees caudad perpendicular to lower leg.. Image-quality criteria include intercondylar eminence clearly visualized in axial view., intercondylar notch open with minimal foreshortening.. Standard exposure ranges from 65 to 75 kVp, 5 to 10 mAs, at an SID of 40 inches (102 cm).

Anatomy demonstrated

  • Intercondylar eminence in axial projection.
  • Intercondylar fossa and notch.
  • Femoral condyles in direct profile.
  • Tibial plateau in axial relationship.
  • Anterior and posterior tibial spines.
  • Attachment sites for cruciate ligaments.

Patient preparation

  • Verify patient identity using two identifiers.
  • Remove shoes and any radiopaque items from the leg.
  • Position patient prone on table with leg extended initially.
  • Flex affected knee 40 to 50 degrees, place foot on table.
  • Ensure pelvis is level and not rotated.

Position & centering point

Intercondylar notch with patient prone and knee flexed 40-50 degrees.

Central ray

40-50 degrees caudad perpendicular to lower leg.

Exposure / technique

kVp
65–75
mAs
5–10
SID
40" (102 cm)
Notes
CR angle matches knee flexion (40-50°) so beam is perpendicular to the lower leg.

Image-quality criteria

  • Intercondylar eminence clearly visualized in axial view.
  • Intercondylar notch open with minimal foreshortening.
  • Femoral condyles in profile showing both anterior and posterior.
  • Tibial plateau included in axial projection.
  • Anterior and posterior tibial spines differentiated.
  • Collimation 1.5 inches on all sides around knee area.

Common errors / ARRT traps

  1. 1 Knee flexion angle less than 40 degrees results in foreshortening.
  2. 2 Flexion greater than 50 degrees closes intercondylar notch.
  3. 3 CR not perpendicular to lower leg distorts intercondylar anatomy.
  4. 4 Pelvis rotation tilts knee alignment.

Clinical indications

  • Intercondylar eminence and tibial spine fracture assessment.
  • Evaluation of anterior cruciate ligament origin.
  • Posterior cruciate ligament attachment visualization.
  • Intercondylar fossa loose body detection.

Aligned to the 2025 ARRT Content Specifications.

Practice this projection live.

The interactive positioning viewer in the app lets you rotate the patient, see the centering point in 3D, and study the central ray angle. Start free.

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