Which of the following is included as a registration step for knee procedures?

• A. Knee Center
• B. Hip Center
• C. Ankle Center
• D. All of the Above

Answer: (D)

Registration steps in knee procedures often involve locating reference points along the entire leg to establish a consistent coordinate system. The hip center provides a proximal reference, the knee center anchors the knee region, and the ankle center gives a distal reference. Using all three centers defines the leg’s mechanical axis from hip to ankle, which is essential for accurate implant placement and alignment in knee procedures. If only one center were used, the system wouldn’t have a global frame to map movements along the limb, increasing the risk of malalignment. That’s why the registration process includes all three centers—so “All of the Above” is the best answer.