Lateral hips - challenges, techniques and dose Flashcards
Why is it so important to get hip x-rays right.
If imaging is not of good quality, fracture may be missed leading to delays in treatment and increased mortality
Why do a HBL hip
To see a missed fracture (The hip, in particular, is at risk for occult fracture as the proximal femur has a high percentage of trabecular bone, a type of bone in which disruption is more difficult to detect than in cortical bone)
To see how displaced a fracture is
What are the treatment options, and what types of fractures lead to that treatment options?
Replacement arthroplasty with displaced intracapsular fractures
Extramedullary implants with trochanteric fractures
E.g., DHS, sliding hip screw
Intramedullary nail with subtrochanteric fractures
What makes a good HBL hip?
The lesser trochanter should be in profile medially.
The greater trochanter superimposed on the femoral shaft.
The femoral neck in the centre of the collimated field and not foreshortened.
The articulation of the acetabulum with the head of the femur entirely demonstrated and well penetrated.
What leads to poor HBL images?
Were generally underexposed and did not clearly demonstrate all of the required anatomy.
Had not been collimated sufficiently and therefore detail was lost due to scattered radiation.
Had not been centred correctly and, when the AEC had been used, this led to premature termination of the exposure
In many cases had not had the voltages increased from the preset standard exposure.
Showed that image quality suffered if the central ray had not been aligned to the grid due to grid cut-off.
Generally had higher DAPs.
What would an ideal BCU look like on hip images
(BCU= brightness, contrast, unsharpness)
10 point check?
Brightness: I can differentiate air, soft tissue and bone
Contrast: I can see the cortex bone and trabecular pattern of the bone
unsharpness: I can see the cortex of the bone clearly, and can trace around the head of the femur, and identify where it is in relation to the acetabulum
Positioning: its not rotated, as I can see the lesser trochanter
Centering: Neck of femur
What is good technique for HBL hips
Accurate centring
Accurate collimation
Use of grid
Optimized exposure – higher kV