A Hip Lateral Without Moving the Fracture
An 84-year-old woman is brought to the emergency department after a fall at home. Her left leg is shortened and externally rotated, and she has 8/10 pain in the left hip. She weighs 96 kg, is mildly confused at baseline, has an IV in the right antecubital fossa, and is on 2 L/min nasal cannula. The emergency physician requests an AP pelvis and a left lateral hip. She cannot internally rotate the left leg or lift it, and she cries out when the leg is moved. She is lying on a soft trolley mattress with a trauma board underneath and keeps sliding down. The department has no fracture table. A DR detector and a grid are available; the room's table has a 200 kg limit. The ED is busy, and the physician wants images within 20 minutes before deciding on surgery.
1. Which projections do you perform, and how do you obtain each one without moving the injured leg?
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AP pelvis.
- Keep the patient supine as she lies; do not internally rotate the left leg.
- Centre midway between the ASIS and the symphysis, collimate to the pelvis, use a grid and AEC or manual technique given the soft mattress.
- The left leg's external rotation will be visible; document it as a clinical finding and positioning limitation rather than forcing correction.
- The trauma board supports the patient; it is not a shield.
Left lateral hip.
- Use the cross-table (Danelius-Miller) approach: detector vertical in the groin, beam horizontal and perpendicular to the femoral neck from the lateral side.
- The unaffected leg is flexed and abducted and held by an assistant to make room; the affected leg is not moved.
- If she cannot tolerate even that, do not force it. Consider a modified cross-table lateral with the detector lateral to the hip, or discuss CT with the ED physician; CT is often definitive for an occult femoral neck fracture.
- Do not attempt a frog-leg or a standard lateral that requires rolling the patient.
2. How do you manage the AP pelvis given the soft mattress and sliding, and what do you do if the image is non-diagnostic?
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Positioning. Use the trauma board, raise the trolley to a workable height, and get a second person to help align her. Re-position rather than accept a rotated film. Sliding is a patient-safety risk as well as an image-quality problem, so fix the cause instead of repeating.
If non-diagnostic:
- Decide whether a repeat would fix the specific deficiency (rotation, cut-off, motion) or whether the examination itself is wrong for the question.
- An AP pelvis may not be the best test if she is in severe pain; an AP hip or femur, or CT, may be more appropriate.
- Call the ED physician, state the limitation clearly, and ask whether CT is appropriate.
- Repeat only once, and document the reason. Serial repeats in a patient in pain add dose without adding information.
The radiologist decides whether the examination is complete; the radiographer's job is to produce the best obtainable images and to flag what was not achievable.
3. What patient-care and radiation-protection considerations apply here?
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Patient care: analgesia before positioning; explain each step; keep her warm and covered; monitor confusion and vital signs; protect the IV; use help for manual handling; keep the trolley at a safe height.
Radiation protection:
- Tight collimation, correct centring and a grid reduce the need for repeats.
- Gonadal shielding is not useful at 84 and can obscure the femoral neck; skip it.
- Staff stand behind the screen and wear lead aprons if holding is unavoidable, which it rarely is with a cooperative team and a cross-table technique.
Communication: tell the ED physician what was achievable and what was not, and document the limitations. The radiologist will interpret the external rotation and any fracture; the radiographer should not offer a diagnosis, but should make sure the clinical team knows the images are limited and that further imaging may be needed.