Partial Knee Replacements

Posted on Friday, June 28, 2019 in Videos

Sometimes a partial knee replacement is the right procedure for patients with ongoing knee pain. Dr. Anthony Berni of Signature Orthopedics St. Charles explains the differences between partial and total knee replacements and the situations when each is appropriate.


Partial knee replacements are a minimally or less invasive surgical alternative to complete knee replacement surgery. Partial knee replacements are extremely successful - at least as successful as complete knee replacements.

The knee can be thought of having three compartments: the area underneath the kneecap, the inside runner, and the outside runner. Any one of those three compartments can be replaced individually if they are worn out.

Compartments of the knee diagram

People that have isolated pain on one side of their knee or the other or just underneath their kneecap are excellent candidates for partial knee replacements. People that have all-over knee pain really need the complete knee replacement.

Degenerative arthritis is interesting. Sometimes it is only localized to one compartment of the knee - that can be post-traumatic, it can be an injury in football when somebody's younger, it can just be a pre-programmed wear pattern that you have only to have one area of the knee that's involved.

This shows arthritis in all three compartments where you would typically do a complete knee replacement meaning resurfacing the entire surface of this knee. The unicompartmental arthroplasty, however, only resurfaces one area of the knee that's diseased. the remainder of the knee that's not diseased does not get violated or touched. Additionally, the cruciate ligaments which are in the center of the knee are left alone and preserved. The knee has more normal biomechanics and behaves like a natural knee exactly with the partial knee replacements.