Which statement best describes the impact of coronal plane malalignment on knee arthroplasty longevity?

• A. Improves wear durability
• B. Increases uneven load distribution
• C. Has no effect on implant longevity
• D. Reduces risk of loosening

Answer: (B)

Coronal plane malalignment after knee arthroplasty shifts load away from a balanced distribution between the medial and lateral compartments. This creates uneven contact stresses on the polyethylene insert and at the bone-implant interfaces. The consequence is accelerated wear on the overloaded side, plus stress concentrations that can drive bone remodeling and osteolysis, increasing the risk of loosening over time. In short, malalignment leads to uneven load distribution, which harms implant longevity. The other statements don’t fit: malalignment does not improve wear durability, it does have an effect on longevity, and it does not reduce the risk of loosening—in fact, it raises that risk.