Radiographic distortion artifact of circular external fixators

Area of Science:

• Orthopedic surgery
• Medical imaging
• Radiography

Background:

• Circular external fixators are vital orthopedic devices.
• Radiographic distortion can misrepresent transfixing wire location, affecting patient outcomes.
• Understanding distortion is crucial for accurate interpretation.

Purpose of the Study:

• To evaluate radiographic distortion in three circular external fixator systems.
• To determine the impact of transfixing wire angles (30°, 60°, 90°) on distortion.
• To identify optimal positioning to minimize artifact.

Main Methods:

• Assessed distortion of three circular external fixator apparatuses.
• Varied transfixing wire angles relative to the X-ray beam (30°, 60°, 90°).
• Measured distortion at different degrees of rotation from parallel to the central X-ray beam.

Main Results:

• Maximum distortion occurred at 10° rotation from parallel for all apparatuses.
• Distortion was most significant with transfixing wires at a 30° angle.
• Smaller angles and greater distance from the X-ray table increased distortion.

Conclusions:

• Distortion artifact is most severe at smaller wire angles and increased distance from the table.
• Positioning the fixator parallel to the X-ray beam and close to the table minimizes artifact.
• Proper positioning aids accurate radiographic interpretation and prevents unnecessary procedures.