Lateral Hip on a Patient Who Cannot Be Moved
A 78-year-old woman is brought to the emergency department after a fall at home. Her right leg is shortened and externally rotated, and she has severe right hip pain. The ED physician's request reads: 'AP pelvis and lateral right hip.' She can lie supine but cries out and grips the technologist's hand when the right leg is moved even slightly; she cannot abduct or externally rotate the leg. She is hard of hearing and speaks only the local language. The ED is busy, and the nurse tells the technologist that the radiologist 'always wants the frog-leg view.'
1. Which lateral projection of the hip will you perform, and how will you position for it?
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The cross-table (Danelius-Miller) lateral. The clinical picture - shortening, external rotation, and pain on any movement - is a suspected femoral neck fracture, and the frog-leg lateral requires abduction and external rotation, which risks displacement.
Positioning: patient supine, no attempt to move the affected leg into abduction or external rotation; slight internal rotation of the foot only if it is tolerated. Place the detector vertically, supported, against the lateral aspect of the hip at the level of the femoral neck and groin, with the unaffected leg raised and supported out of the way. Direct a horizontal beam perpendicular to the femoral neck and to the detector, centring to the femoral neck, at the longest SID the arrangement allows (around 100 cm), with collimation to include the hip joint and the proximal femur. Explain each step in her language, keep your hand available to hold, and warn before any movement.
2. How will you know whether the resulting image is a true lateral and adequate?
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Check that the femoral head and neck are demonstrated in profile with the acetabulum, with no greater-trochanter superimposition over the neck. If the greater trochanter is projected over the femoral neck, the leg is externally rotated relative to the beam - correct by gently rotating the foot and leg internally within the patient's tolerance, or by angling the tube about 15 to 20 degrees.
Also confirm: the image includes the femoral head through to below the lesser trochanter, the joint space and acetabulum are visible, the field is collimated without cutting the neck, there is no motion blur, and there is no rotation artefact from the detector being off perpendicular. Mark the right side clearly and note the patient's inability to internally rotate on the request if it persists, because persistent external rotation is itself a clinical finding.
3. The nurse insists on the frog-leg view because 'the radiologist always wants it.' How do you handle it?
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Advocate for the patient rather than comply. The frog-leg position demands abduction and external rotation of a limb with a probable femoral neck fracture; it is painful, may displace the fracture, and is not justified when an alternative projection answers the clinical question.
Steps: explain the risk to the nurse and offer to speak to the ED physician and the radiologist. Ask whether analgesia can be given to make the cross-table lateral tolerable, and point out that CT is available if the radiologist needs more than plain films. Do not perform a contraindicated view on a nurse's instruction - the order comes from a physician, and the physician can be asked to amend it. Document the refusal, the reason, the person you spoke to, and the alternative provided. If the radiologist, after being told the clinical situation, still wants it, get that instruction clearly and record it before acting.