M11: Knee, Patella

Positioning for AP Knee

Patient supine with affected leg extended, centered to IR, long axis to long axis of IR, femoral epicondyles equidistant to IR

CR + CP for AP Knee

CR: Depends on pelvis <19cm=5 degree CD, 19cm-24cm=PPD, >24cm=5 degrees CL

CP: 1cm distal to patellar apex

SI for AP Knee

Distal 1/4 femur, patella and proximal 1/4 tibia and fibula, knee joint to mid IR

Positioning for AP OBL MED ROT Knee

Rotate affected leg 45⁰ medially, support obliquity with sponge, long hip to ankle in the same plane, long axis of leg aligned with long axis of IR

CR + CP for AP OBL MED ROT Knee

CR: Depends on pelvis <19cm=5 degree CD, 19cm-24cm=PPD, >24cm=5 degrees CL

CP: 1cm distal to patellar apex

SI for AP OBL MED ROT Knee

Distal femur, patella and proximal tibia and fibula

Positioning for AP OBL LAT ROT Knee

Rotate affected leg 45⁰ externally, long axis of leg aligned with long axis of IR, knee joint centered to IR

CR + CP for AP OBL LAT ROT Knee

CR: Depends on pelvis <19cm=5 degree CD, 19cm-24cm=PPD, >24cm=5 degrees CL

CP: 1cm distal to patellar apex

SI for AP OBL LAT ROT Knee

Distal femur, patella and proximal tibia and fibula

Positioning for LAT Knee

Patient in lateral recumbent of affected side, knee flexed 20-30 degrees, hip to knee in the same plane, knee to ankle in the same plane, anterior surface of patella is perpendicular to IR, femoral condyles SI

CR + CP for LAT Knee

CR: 5-7 degrees cephalad

CP: 2.5cm distal to medial femoral condyle, midway

SI for LAT Knee

Distal femur, patella and proximal tibia and fibula

Positioning for TANG Patella

Patient sitting or lying on table, knee flexed, IR is placed against thigh so CR is perpendicular to it, patellofemoral joint to mid IR, collimated tightly

CR + CP for TANG Patella

CR: Parallel to Patellofemoral Joint

CP: Patellofemoral Joint

SI for TANG Patella

Patella and distal femur

Positioning for NOTCH Fossa

Flex knee so that femur is 60⁰ to table, IR under knee, no rotation, beam centered to IR entering 1 cm distal to patella apex, tight collimation

CR + CP for NOTCH Fossa

CR: PPD to TibFib

CP: Knee Joint

SI for NOTCH Fossa

Distal femoral condyles, proximal tibia and fibula