Is There Any Difference Between a Spherical Marker and a Simple Coin for Hip Replacement Digital Planning?

Area of Science:

• Orthopedic Surgery
• Radiology
• Medical Imaging

Background:

• Accurate preoperative planning is crucial for successful hip arthroplasty.
• Radiographic calibration relies on precise measurement tools.
• Metallic markers are used to ensure accuracy in imaging.

Purpose of the Study:

• To compare the accuracy of spherical and coin-shaped metallic markers for radiographic calibration.
• To evaluate marker performance in preoperative planning for hip arthroplasty.
• To determine the optimal marker type and placement for hip imaging.

Main Methods:

• 33 patients undergoing hip arthroplasty were included.
• Spherical and coin markers (25mm diameter) were placed at various anatomical locations.
• Image diameters were measured, and statistical analysis was performed.

Main Results:

• Coin markers placed between the thighs showed higher accuracy (50-60%) compared to spheres.
• Markers on the greater trochanter had variable visualization rates (up to 57.6% not visualized).
• Coin and sphere markers on the exam table showed minimal size reduction and easier positioning.

Conclusions:

• The coin marker positioned between the thighs is recommended for hip arthroplasty radiographic calibration.
• Using a coin marker on the exam table for comparison is suggested.
• A slight size reduction (8%) of markers should be considered in measurements.