Partial Knee Replacement

Understanding your knee's three compartments

Your knee is divided into three functional compartments: medial (inside), lateral (outside), and patellofemoral (behind the kneecap). Osteoarthritis often starts in just one of these areas, especially the medial compartment. When damage is confined to a single compartment and the rest of the joint — along with your ACL and other supporting ligaments — remains healthy, a partial knee replacement becomes a reasonable option.

Why preserving healthy bone and ligaments matters

Because a partial knee replacement resurfaces only the damaged compartment, the healthy bone, cartilage, and ligaments elsewhere in the joint are left intact. Many patients describe the resulting knee as feeling more natural than a total knee replacement, since the joint continues to move the way it always has in the preserved areas.

The procedure is done through a smaller incision than a total knee replacement, which typically translates to less blood loss, a shorter hospital stay, and a quicker return to normal activity.

The honest tradeoff

Partial knee replacement isn't for everyone, and it isn't necessarily permanent in the way a total knee replacement is. If arthritis later develops in one of the compartments that wasn't replaced, a conversion to total knee replacement may eventually be needed. That's a conversation worth having up front, not after the fact — and it's one reason candidacy for this procedure should be determined by imaging and a hands-on exam, not assumed.