Which statement best describes the cement mantle in hip arthroplasty, and how its quality is evaluated radiographically?

• A. The space between the implant and surrounding bone margins, evaluated by bone density on X-ray.
• B. The layer of bone cement between the implant and bone; quality is determined by the amount of cement used, not radiographic appearance.
• C. The layer of bone cement between the implant and bone; quality is assessed by uniform cement distribution with minimal radiolucencies; radiolucent lines greater than 2 mm may indicate loosening risk.
• D. The overlay of cement particles on the prosthesis surface; evaluated by surface roughness.

Answer: (C)

The cement mantle is the layer of bone cement that sits between the implant and the bone. Its quality is judged on radiographs by how evenly the cement is distributed around the implant and how clean the interfaces look. A uniform mantle with minimal radiolucent lines suggests a good bond and stable fixation, while radiolucent lines, especially if they exceed about 2 mm, raise concern for gaps that can allow micromotion and loosening over time. In short, radiographs evaluate the mantle’s continuity and the presence of lucencies; a well-seated, evenly distributed mantle with only small or no radiolucencies indicates a lower risk of loosening.