Radiolucencies surrounding acetabular components with three-dimensional coatings: artifact or real?

Area of Science:

• Orthopedic surgery
• Biomaterials science
• Radiology

Background:

• Cementless acetabular fixation utilizes 2D and 3D surfaces.
• Plain radiographs assess osseointegration but have limitations in capturing 3D fixation.
• Cadaveric study to compare bone apposition between 2D and 3D cups.

Purpose of the Study:

• To compare bone apposition between 2D and 3D acetabular cups.
• To evaluate the accuracy of plain radiographs in assessing osseointegration for both cup types.

Main Methods:

• Implantation of 2D and 3D cups in 6 cadavers.
• Pelvic radiographs and sectioning of cups with surrounding bone.
• Analysis of metal-bone interface using photographs and contact radiographs.

Main Results:

• Pelvic radiographs showed <30% radiolucencies for both cup types.
• Section analysis revealed ~80% aggregate metal-bone contact for both cup types.
• Inconsistencies between radiographs and photographs noted for 3D cups.

Conclusions:

• Both 2D and 3D cups achieved good metal-bone contact (>75%).
• Radiographic artifacts may occur with 3D cups due to surface interactions.
• Radiographs may overestimate radiolucencies for 3D acetabular components.