Severe Hip Pain After a Fall: Positioning Without Moving the Fracture
An 82-year-old woman is brought to the emergency department after falling at home. She has severe right hip pain (8/10), the right leg is shortened and externally rotated, and she cannot bear weight. The emergency physician requests an AP pelvis and a right lateral hip radiograph. The department has a 500 mA unit, a CR system and a horizontal-beam cross-table lateral capability. The patient weighs 95 kg, is on warfarin for atrial fibrillation, and has a painful right hip that she refuses to move. She is alert but anxious and has no known contrast allergy. The radiographer has one assistant. The routine protocol is AP pelvis at 100 cm SID with a grid, and lateral hip cross-table at 100 cm SID. The patient's daughter asks whether the leg can be straightened for the lateral view. The emergency department is busy and the patient has been waiting 40 minutes.
1. Describe how you would position the patient for the AP pelvis and the cross-table right lateral hip without straightening or rotating the injured leg.
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I would keep the right leg in the position found and avoid any forced movement.
AP pelvis:
- Place the cassette landscape behind the patient, centred at approximately the level midway between the anterior superior iliac spines and the symphysis pubis.
- Keep both legs extended and in neutral alignment; do not pull the right leg into internal rotation.
- Use a 100 cm SID and collimate to the pelvis. Centre the beam to include both iliac crests and the proximal femora.
Cross-table right lateral hip:
- Leave the patient supine and the right leg undisturbed.
- Place the cassette vertically against the lateral aspect of the right hip, supported by a cassette holder or assistant.
- Direct the horizontal beam from the medial side toward the lateral cassette, centring over the femoral neck and head.
- Flex and elevate the unaffected left leg if the patient can tolerate it, to clear superimposition; support it with a pillow rather than asking her to hold it.
- Collimate tightly and use a grid.
Reasoning: straightening or internally rotating the leg risks displacing the fracture, increasing pain and possibly causing vascular or nerve injury. The cross-table lateral is chosen precisely because it obtains a lateral projection without moving the injured limb.
2. How would you select exposure factors and shielding for this 95 kg patient, and what would you say to the daughter who asks about straightening the leg?
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For a 95 kg patient I would use a higher kVp and sufficient mAs to penetrate the pelvis, with a grid and tight collimation. A typical starting point might be about 80–90 kVp with manual exposure factors adjusted to the department's chart, rather than relying blindly on AEC, because the patient's position and the cassette placement may make AEC unreliable. I would avoid repeat exposures by checking the cassette position and centring before pressing the button.
Shielding: I would not place a gonadal shield over the hip or pelvis in this 82-year-old patient, because the clinical question is the fracture and the shield may obscure the femoral neck. Collimation is the main protection. Her warfarin therapy does not contraindicate plain radiography.
To the daughter: I would explain that the leg must not be straightened for the X-ray because the hip may be fractured, and pulling it could cause further damage and severe pain. The cross-table lateral is specifically designed to show the hip from the side while the leg stays still. I would also tell her that we will support the leg with pillows and work quickly, and that she should tell us if her mother's pain worsens. If pain is uncontrolled, I would ask the emergency physician to review analgesia before proceeding.
3. What would you document and communicate to the emergency team after the examination?
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I would document that the patient had a suspected right hip fracture with a shortened, externally rotated leg, that the right leg was not moved, and that AP pelvis and cross-table right lateral hip views were obtained. I would record the exposure factors, the number of exposures, any difficulty with positioning, and whether the images were diagnostic.
I would also note:
- The patient's pain score and any analgesia requested or given before the examination.
- That the daughter was advised why the leg should not be straightened.
- Any limitation of the study, for example if the lateral hip was partly obscured by the cassette holder or if the patient could not tolerate elevation of the opposite leg.
I would communicate directly to the emergency physician that the images are available for review and that the patient remains in severe pain. If the radiograph suggests a displaced fracture, I would ensure that the report is prioritised rather than leaving the films for routine reporting.