Custom-made 3D-printed knee prostheses

Individual knee prostheses, custom-made from a 3D printer

Once advanced knee osteoarthritis has been diagnosed and the decision to opt for a knee replacement has been made, then the question arises as to which prosthesis best suits the patient’s needs.

In knee arthroplasty, there has been a great development in recent years: individually-customised 3D-printed prostheses.

These implants take into account the anatomy of the knee joint, which is extremely complicated and varies from patient to patient.

For the production and implantation of a personalised knee prosthesis, a CT scan is first taken according to protocol. This is sent to the manufacturer.

Using a software, the CT scan is analysed and a virtual 3D knee is created.

The condyle curves of the femur, the troclea curve and the always asymmetrical tibial plateau are calculated with maximum precision.

The optimal cutting templates and knee prosthesis implants are then calculated for this knee and the 3D printer prints them out.

Six weeks after the CT scan and the placement of the order, the prosthesis, including cut templates, are sent in a box.

The personalised prosthesis, made for your knee only, is ready to be implanted.

In the box, there is also the surgical planning for femur and tibia with details of the resections.

This allows the surgeon to be well prepared for the operation, but also to constantly monitor the course of the surgical procedure.

As a result, a prosthesis with the exact size of the femur and tibia is implanted. The prosthesis sits exactly on the marginal cortical bone (and not on the soft spongy bone), thus avoiding sinking.

Under- or over-dimensioning the prosthesis is also avoided if correctly performed, which is often a problem with standard implants.

The soft tissues are also considered.For example, the prosthesis components have a recess for the popliteal ligament, which is not considered in standard implants and sometimes causes soft tissue irritation and discomfort.

Results show higher patient satisfaction, less bone resection, a better fit, less trauma, less blood loss and faster mobility. Patients can also expect a longer service life.