In Vitro Evaluation of a Device to Assess Acetabular Cup Position by Sagittal Plane Radiography.

Area of Science:

• Orthopedic surgery
• Medical device technology
• Radiographic analysis

Background:

• Accurate assessment of acetabular component positioning is crucial in hip arthroplasty.
• Existing methods for measuring angle of lateral opening (ALO) and open-face version may have limitations.

Purpose of the Study:

• To compare the calculated ALO and open-face version using a CPAD against known values.
• To evaluate the accuracy and reliability of the CPAD for assessing acetabular component alignment.

Main Methods:

• Simulated sagittal plane pelvic radiographs were created using a BFX™ acetabular component with a CPAD.
• Images were captured at various ALO angles (30-60 degrees) with 0-degree open-face version, repeated triplicates.
• Paired t-tests and Lin's Concordance Correlation Coefficient were used for statistical analysis.

Main Results:

• Calculated ALO showed no significant difference from known ALO (p=0.608) with near-perfect correlation (Rc=0.994).
• Calculated open-face version demonstrated significant differences compared to known values.
• The CPAD proved to be an accurate tool for determining ALO in simulated radiographic views.

Conclusions:

• The CPAD is a reliable device for measuring the angle of lateral opening in simulated pelvic radiographs.
• Further investigation is needed to refine the accuracy of the CPAD for open-face version measurements.