IBA - Lower Limb & Pelvis.pdf

Projection Appraisal: DP Foot: ▪ Equal spacing between 2nd-5th metatarsals Centring: ▪ Joint space between medial and intermediate cuneiforms Angled 15 is open...

Projection Appraisal: DP Foot: ▪ Equal spacing between 2nd-5th metatarsals Centring: ▪ Joint space between medial and intermediate cuneiforms Angled 15 is open degrees ▪ 1/3 of talus is superimposing the calcaneus cranially to ▪ Tarsometatarsal and navicular-cuneiform joint spaces are cuboid-navicular open joint (midway ▪ Third metatarsal base is at the centre of the exposure between field navicular and 5th ▪ Proximal calcaneus, talar neck, MTs and phalanges and MT tuberosity) soft tissues are included Exposure Factors: 57kVp 1.4mAs Fine focus No grid 100cm SID DP Oblique Foot: ▪ Cuboid-cuneiform joint space is open Centring: ▪ 2nd-5th metatarsophalangeal joints are open Cuboid- ▪ Bases of 1st and 2nd metatarsals superimposed navicular joint ▪ Tarsal sinus is open (midway ▪ 5th metatarsal tuberosity is in profile between ▪ 3rd MT base is at the centre of the exposure field navicular and 5th ▪ Proximal calcaneus, talar neck, MTs and phalanges and MT tuberosity) soft tissues are included Exposure Factors: 57kVp 1.4mAs Fine focus No grid 100cm SID AP Mortise Ankle: ▪ Distal fibula is demonstrated without talar Centring: superimposition - open mortise Midway ▪ Lateral and medial malleoli are in profile between medial ▪ Tarsal sinus is demonstrated and lateral ▪ Tibiotalar joint space is open and at the centre of the malleoli exposure field ▪ Calcaneus is visualised distal to the lateral mortise and the Exposure fibula Factors: ▪ Distal 1/4 of tib/fib, talus and soft tissue is included 57kVp 3mAs Fine focus No grid 100cm SID LAT Ankle: ▪ Ankle dorsiflexed to be at 90 degrees with tib/fib Centring: ▪ Proximal aspects of the talar domes are aligned and Medial superimposed malleolus ▪ Anterior and posterior talar domes are aligned ▪ Tibiotalar joint space is open and is at the centre of the Exposure exposure field Factors: ▪ Distal fibula is superimposed by the posterior half of the 59kVp distal tibia 3mAs Fine focus No grid 100cm SID AP Tib/Fib: ▪ Tibia superimposes 1/4 of fibular head and 1/2 of distal Centring: fibula Midshaft of ▪ Fibular midshaft is free of tibial superimposition tibia, midway ▪ Tibial midshaft is at the centre of the exposure field between ankle ▪ Knee and tibiotalar joint spaces are slightly closed due to and knee joints beam divergence Exposure Factors: 62kVp 3.2mAs Fine focus No grid 100-110cm SID (increase to fit entire ROI) LAT Tib/Fib: ▪ Tibia superimposed 1/2 of fibular head Centring: ▪ Fibular midshaft is demonstrated free of tibial Midshaft of superimposition tibia, midway ▪ Posterior aspects of distal tibia and fibula are aligned between ankle ▪ Tibial midshaft is at the centre of the exposure field and knee joints ▪ Knee and tibiotalar joint spaces are slightly closed due to beam divergence Exposure Factors: 62kVp 3.2mAs Fine focus No grid 100-110cm SID (increased to fit entire ROI) AP Knee: ▪ Femoral condyles are in profile and equidistant from IR Centring: ▪ Intercondylar eminence is centred within the Tibial plateau – intercondylar notch 2.5cm distal to ▪ Tibia superimposes 1/2 of the fibular head apex of patella ▪ Patella lies proximal to femoral patellar surface and is in the knee midline Exposure ▪ Femorotibial joint space is open Factors: ▪ Anterior and posterior distal tibial margins are aligned 6.3kVp ▪ Fibular head is 1/2 an inch distal to the tibial plateau 3.6mAs Fine focus No grid 100cm SID LAT Knee: ▪ Patella is situated proximal to the patella surface of the Centring: femur Angled 5-7 ▪ Patellofemoral joint is open degrees ▪ Distal margins of the medial and lateral femoral condyles cranially to mid- are aligned superior border ▪ Fibular head is 1/2 an inch distal to the tibial plateau of medial tibial ▪ Femorotibial knee joint space is open condyle ▪ Anterior and posterior margins of the medial and lateral femoral condyles are aligned Exposure ▪ Tibia superimposes 1/2 of the fibular head factors: ▪ Knee joint is at the centre of the exposure field 63kVp 3.6mAs Fine focus No grid 100cm SID AP Distal Femur: ▪ Image brightness is uniform across the femur - position Centring: the proximal femur at the cathode end of the tube and Midshaft of the distal femur at the end of the tube femur ▪ Femoral condyles are seen in profile - knee is fully Inferior border extended of detector ▪ Femoral condyles are symmetric in shape - leg is internally placed 5cm rotated below knee ▪ Tibia superimposes half of the fibular head joint ▪ Long axis of the femoral shaft is aligned with the long axis of the collimated field Exposure ▪ Distal femoral shaft is at the centre of the exposure field Factors: ▪ 2 inches of overlap with the proximal AP femur projection 65-70kVp is evident if the entire femur is imaged 10-16mAs ▪ All relevant anatomy is included: Fine focus ▪ Inferiorly, the distal femoral shaft, knee joint and 1cm of No grid the tib/fib 100-120cm SID ▪ Laterally, soft tissue margins ▪ Superiorly, distal 2/3 of the femoral shaft AP Proximal Femur: ▪ Image brightness is uniform across the femur - position Centring: the proximal femur at the cathode end and the distal Midshaft of femur at the anode end femur ▪ Ischial spine is aligned with the pelvic brim Superior border ▪ Obturator foramen is open of detector at ▪ Femoral neck is demonstrated without foreshortening level of ASIS ▪ Greater trochanter is in profile laterally ▪ Lesser trochanter is completely superimposed by the Exposure proximal femur Factors: ▪ Long axis of the femoral shaft is aligned with the long axis 70kVp of the exposure field 20-30mAs ▪ Proximal femoral midshaft is at the centre of the exposure Broad focus field Grid required ▪ All relevant anatomy is included: 100cm SID ▪ Superiorly, the entire hip joint, ASIS is at the superior border of the detector ▪ Laterally, the soft tissue margins ▪ Distally, proximal 2/3 of femur ▪ 2 inches overlap is evident with the proximal lateral femur projection if the entire femur is imaged LAT Distal Femur: ▪ Image brightness is uniform across the femur - place the Centring: proximal femur at the cathode end of the tube and the Midshaft of knee at the anode end of the tube femur ▪ Anterior and posterior margins of the medial and lateral Inferior border femoral condyles are aligned of detector ▪ Femoral shaft is seen without foreshortening with the placed 5cm medial femoral condyle projected 0.5 inch distal to the below knee lateral femoral condyle due to beam divergence joint ▪ Long axis of the femoral shaft is aligned with the long axis of the exposure field Exposure ▪ Distal femoral shaft is at the centre of the exposure field Factors: ▪ Unaffected leg is not demonstrated on the projection 65-70kVp ▪ All relevant anatomy is included: 10-16mAs ▪ Superiorly, the distal 2/3 of the femur Fine focus ▪ Laterally, the anterior and posterior soft tissue margins 100-120cm SID ▪ Distally, the knee joint and 1 inch of the lower leg ▪ 2 inches overlap is evident with the proximal lateral femur projection if the entire femur is imaged LAT Proximal Femur: ▪ Image brightness is uniform across the femur - place the Centring: proximal femur at the cathode end and the distal femur at Midshaft of the anode end femur ▪ Lesser trochanter is in profile medially Superior border ▪ Femoral neck and head are superimposed over the of detector at greater trochanter level of ASIS ▪ Femoral shaft is seen without foreshortening ▪ Femoral neck is demonstrated on end Exposure ▪ Greater trochanter is demonstrated at the same Factors: transverse level as the femoral head - distal femur is not 70kVp elevated and the entire femur is placed against the table 20-30mAs ▪ Long axis of the femoral shaft is aligned with the long axis Broad focus of the exposure field Grid required ▪ Proximal shaft is at the centre of the exposure field 100cm SID ▪ All relevant anatomy included: ▪ Superiorly, entire hip joint, proximal 2/3 of femur ▪ Laterally, anterior and posterior soft tissue margins ▪ Inferiorly, proximal 2/3 of femur AP Hip: ▪ Ischial spine is aligned with the pelvic brim Centring: ▪ Sacrum and coccyx are aligned with the symphysis pubis Centred 2.5cm ▪ Obturator foramen is open distally along ▪ Femoral neck is demonstrated without foreshortening the ▪ Greater trochanter is in profile laterally perpendicular ▪ Lesser trochanter is superimposed by the femoral neck bisector of a line ▪ Femoral head and neck are at the centre of the exposure joining the ASIS field and the ▪ All relevant anatomy are included: symphysis pubis ▪ Acetabulum, greater and lesser trochanters, femoral head and neck, half of the sacrum, coccyx and symphysis pubis Exposure Factors: 70kVp 20-30mAs Broad focus Grid required 100cm SID Turned LAT Hip: ▪ Soft tissue of the unaffected thigh dose not superimpose Centring: the femoral head or neck Level of femoral ▪ Femoral neck is demonstrated without foreshortening pulse ▪ Greater and lesser trochanters are demonstrated approximately at the same transverse level Exposure ▪ Lesser trochanter is in profile posteriorly factors: ▪ Greater trochanter is superimposed by the femoral shaft 75kVp ▪ Femoral neck is at the centre of the exposure field 20-30mAs ▪ All relevant anatomy is included: Broad focus ▪ Acetabulum, greater and lesser trochanters, femoral head Grid required and neck, ischial tuberosity 100cm SID AP Pelvis: ▪ Sacrum and coccyx are aligned with the pubic symphysis - no tilt ▪ Obturator foramina are open and uniform in size and shape - no rotation ▪ Iliac wings are symmetrical - no rotation ▪ Femoral neck is demonstrated without foreshortening ▪ Greater trochanters are in profile laterally ▪ Lesser trochanters are superimposed by the femoral necks ▪ Inferior sacrum is at the centre of the exposure field ▪ All relevant anatomy is included: ▪ Iliac wings, symphysis pubis, ischia, acetabula, femoral necks and heads and lesser trochanters are included Exposure Factors: Centring: 75kVp Centred midway between the ASIS and Superior 20-30mAs border of the symphysis pubis + IR 5cm above IC Broad Focus Grid Required 100cm SID