Babeh Edi

Pelvis Hips "Frogs" Lateral

Indications for imaging Congenital abnormalities, Perthes disease, slipped femoral epiphyses. Anatomy  Demonstrated Femoral heads and necks, acetabulum Pelvis Hip Frogs Rt Lateral Anatomy Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy Saunders, London Basic Patient Position The patient lies supine on the table, A.S.I.S.s equidistant from the table top with the midsaggital line in the center of the table. The hips and knees are flexed and the soles of the feet placed together in the midline, the knees are forced down towards the table top as far as possible. Ensure leg positioning is symmetrical.  Pelvis Hips frogs Lateral Patient Position (note unintentional asymmetry) Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy Saunders, London Radiation protection There are many local rules for gonad protection however the following should be taken into account. The 28 day rule should be applied for female patients. In males direct lead rubber gonad protection can be applied at all times In females direct lead rubber gonad protection is generally not advised on the first examination, however if the patient is subsequently examined gonad protection may be used if the area of interest is not obscured. On small patients the omission of a grid will reduced the exposure. Central Ray The vertical central ray is centered in the midline level with the femoral heads. (located a 3 cm below a imaginary line from the ASIS to the symphysis pubis) Exposure Factors Kv mAS FFD (cm) Grid Focus AEC Cassette 85 25 100 Yes Broad/Fine Yes 35 x 43 cm Evaluation of the Image ID and markers must be present and correct in the appropriate area of the film Evidence of collimation on four sides equally around the centering point. Limits of the examination, Superiorly the femoral heads, inferiorly the ischial tuberosity, laterally the proximal femoral shafts. The pelvis should be symmetrical, the lesser trochanters should be symmetrical and visible immediately below the femoral necks. Optimal exposure should penetrate all the bone structures and contrast should be low enough to visualise fully the bone and soft tissue structures. Pelvis Hips Frogs Rt. Lateral Radiograph (Half of the image) Related Projections Variations on this projection some with forced abduction are used in pediatric imaging for unstable hips. Pelvis AP Pelvis horizontal ray hip Lateral. Acetabular projections e.g. Judet's view. Additional modalities RNI CT MRI