patella x ray
8 x 10 in. (18 * 24 cm), lengthwise
Place patient prone (lace down ) on table with pillow under head
Place lead shield over patient to protect gonads
Extend leg of affected or dislocated patella x ray knee, placing support under ankle to prevent pressure on toes,
NOTE: placing the knee on the able causes fractured patella pain x ray, place thin supports under the femur and tibia to relieve pressure Align long axis of leg to mid line of table
Adjust leg to place surface of patella parallel to plane of table.
Center cassette (in Bucky tray ) to mid portion of patella.
Direct central ray perpendicular to enter posterior surface of the knee joint and Exit at mid portion of patella.
Collimate closely for maximum detail, but not So close as to exclude knee Joint space.
Because the patella is superimposed by the femur, this projection generally requires an exposure greater than that normally needed for An AP projection of the knee.
Patella (base, body, and apex) should be clearly Outlined without rotation (although superimposed by femur).
Knee joint should be seen (to evaluate relation of patella to joint space).
An alternative projection for patella x ray views is the AP although in Creased part-film distance causcs excessive magnification and loss of detail. Place patient Supine with leg of affected knee extended.
Center cassette (in Bucky tray ), and direct Central ray perpendicular to mid Portion of patella. Make certain surface of patella is parallel to plane of table in mid line of table
Patella (in profile)
Proximal tibia and fibula
8 x 10 in (18 x 24 cm), lengthwise
Place patient on table in lateral position(turned to side of affected extremity ), making certain that opposite extremity does not interfere with area being radio graphed.
Place pillow under patient’s head
Place lead shield over patient to protect gonads.
NOTE: if there is a recent or suspected patella fracture, do not Flex knee. Have patient partially extend leg allowing knee to flex about 10 degrees
Center patella to midline ot table or cassette (may be done with Bucky or non Bucky exposure depending on departmental procedure)
Adjust rotation of body and entire lower extremity until plane of patella is perpendicular to plane of table.
Center cassette to midportion of patella, making certain to include knee joint space.
Direct central ray perpendiculr to midportion of patella.
Collimate closely tor maximum detail, but not so close as to exclude knee joint space.
To prevent over penetration of the patella, this projection generally requires an exposure less than that for a lateral knce radiograph.
Patella should be scen in profile with femoropatellar joint space well demonstrated.
Knee joint should De seen in lateral position (as evidenced by superimposition of femoral condyles)
skyline view of patella