"Knee replacement" isn't a single operation — there are several versions of it, and which one applies to you depends on exactly where your knee is worn, not just how worn it is.

The knee's three compartments

Your knee joint has three separate compartments: the medial (inner), lateral (outer), and patellofemoral (behind the kneecap). Arthritis frequently affects one compartment more than the others, particularly the medial compartment, which carries the most load during walking.

Partial (unicompartmental) knee replacement

If damage is genuinely confined to a single compartment, a partial replacement resurfaces only that portion of the joint, leaving the healthy compartments and — critically — your natural ligaments intact.

Total knee replacement

When arthritis has spread across multiple compartments — which is the more common presentation by the time patients reach a surgical decision — all three surfaces are resurfaced. Modern implants are designed to replicate the knee's natural rolling and gliding motion as closely as possible.

Robotic-assisted vs. conventional technique

Both partial and total knee replacement can be performed with robotic-arm assistance or with conventional manual instrumentation. Robotic planning uses a pre-operative CT or imaging-based model of your knee to guide implant position and soft-tissue balance in real time during surgery. It's particularly useful where deformity is significant or where partial replacement demands very precise placement to protect the remaining compartments. For straightforward anatomy, conventional technique achieves comparable outcomes with a shorter operating time.

Alignment philosophy matters too. Some surgeons aim to restore your knee's original, pre-arthritic alignment (kinematic alignment) rather than a fixed neutral alignment for every patient. This is discussed and planned individually based on your anatomy.

What determines which option you'll be offered

  1. Which compartments show wear on your imaging
  2. The condition of your ACL and collateral ligaments
  3. Your activity level and goals for recovery
  4. Whether previous knee surgery has altered your anatomy

These are assessed together during your consultation, with your imaging reviewed on screen so you can see exactly what's being discussed.

This guide is for general education and does not replace individual medical advice. Every patient's condition is different — book a consultation with Dr. Abhimanyu Singh to discuss what applies to you.