Standing full length X-ray for HTO - scannogram ? tips

Summary

This video provides essential tips for obtaining proper full-length standing x-rays of the lower limbs, crucial for planning osteotomies in early arthritis cases. It emphasizes the importance of accurate x-ray positioning, including using a 50-inch cassette and a 10-foot distance for the x-ray source. Key steps include rotating the lower limb to face the patella forward, attaching a metallic sphere for calibration, and ensuring no pelvic obliquity. Proper alignment is verified by specific anatomical markers, ensuring an accurate scan for successful surgical planning.

Takeaways

• 🏥 Importance of X-rays: X-rays are crucial for planning osteotomies in joint preservation for early arthritis.
• 📏 Proper Technique: A full-length standing x-ray of the lower limbs is essential for accurate planning.
• 📐 Correct Positioning: The patient should stand with the patella facing forwards and the limb internally rotated until the patella is aligned.
• 🔍 Equipment Use: A 50-inch cassette is used for capturing the full length of the lower limb.
• 📸 X-ray Source: The x-ray source should be kept at a distance of 10 feet for proper exposure.
• 🛡️ Exposure Level: The exposure should be similar to that used for hip or pelvic x-rays.
• 🔨 Marking Tool: A metallic sphere is attached around the lower thigh to provide a size reference in the x-ray.
• 🔍 Sphere Significance: The metal ball ensures a round shadow, aiding in calibration and avoiding misinterpretation from other shapes.
• 👨‍⚕️ Surgeon's Review: The surgeon must carefully study the x-ray to ensure proper technique was used and no errors are present.
• ⚠️ Check for Pelvic Obliquity: Rule out any pelvic obliquity, especially if caused by limb shortening, to ensure accurate assessment.
• 🦵 Limb Length Correction: If there is limb shortening, the shorter limb should be raised on planks to correct pelvic obliquity.
• 🧍‍♂️ Patella Positioning: The patella should be centrally positioned for a proper x-ray view.
• 🦿 Tibial and Fibular Alignment: The lateral border of the tibia should cross the widest part of the fibula, ensuring correct anatomical alignment.
• 🦴 Distal Femur View: The distal femur should be viewed orthogonally for accurate assessment in the x-ray.

Q & A

What is the main purpose of the video?

The main purpose of the video is to provide tips on how to take a proper full-length standing X-ray of the lower limbs, which is crucial for planning osteotomies in joint preservation for early arthritis.

Why are osteotomies increasingly performed for joint preservation in early arthritis?

Osteotomies are performed for joint preservation in early arthritis to delay or avoid the need for joint replacement surgery, thus maintaining the joint's function for a longer period.

What is the importance of X-rays in the planning of osteotomies?

X-rays are vital in planning osteotomies because they provide the necessary images to assess the joint and bone conditions accurately, which in turn influences the quality and effectiveness of the surgical planning.

What is the significance of the patella facing forwards during the X-ray process?

Having the patella facing forwards is important as it ensures the correct alignment and positioning of the lower limb during the X-ray, which is crucial for obtaining accurate and reliable images for surgical planning.

What is the role of a 50-inch cassette in obtaining full-length leg views?

A 50-inch cassette is used to capture the entire length of the lower limb in a single X-ray image, providing a comprehensive view necessary for proper assessment and planning of osteotomies.

How should the patient stand for the X-ray to ensure proper positioning?

The patient should stand with the patella facing forwards and internally rotate the lower limb until the patella is correctly positioned. This ensures that the X-ray captures the limb in its natural, anatomically correct alignment.

What is the recommended distance for the X-ray source during the procedure?

The X-ray source should be kept at a distance of 10 feet from the patient to ensure proper exposure and image quality without overexposing the patient to radiation.

Why is attaching a metallic sphere around the lower thigh important in the X-ray process?

Attaching a metallic sphere around the lower thigh helps in calibrating the size and dimensions of the bone, as the sphere always casts a round shadow that can be easily measured and compared on the X-ray image.

How can the metallic sphere be used for calibration in X-ray images?

The metallic sphere, being a consistent size, can be calibrated in any imaging software or even on a tracing to provide a reference point for measuring bone dimensions and angles in the X-ray images.

What should the surgeon do after the X-ray is taken?

The surgeon should study the X-ray to ensure it is taken properly, checking for correct pelvic alignment, central patella positioning, and proper overlap of the tibia and fibula, as well as an orthogonal view of the distal femur.

What is the significance of checking for pelvic obliquity in the X-ray?

Checking for pelvic obliquity is important because it can indicate limb shortening or other alignment issues. If present, adjustments such as raising the shorter limb on planks may be necessary to correct the obliquity before proceeding with surgical planning.