New Technologies in Knee Arthroplasty: Current Concepts

Abstract

Total knee arthroplasty (TKA) is an effective treatment for severe osteoarthritis. Despite good survival rates, up to 20% of TKA patients remain dissatisfied. Recently, promising new technologies have been developed in knee arthroplasty, and could improve the functional outcomes. The aim of this paper was to present some new technologies in TKA, their current concepts, their advantages, and limitations. The patient-specific instrumentations can allow an improvement of implant positioning and limb alignment, but no difference is found for functional outcomes. The customized implants are conceived to reproduce the native knee anatomy and to reproduce its biomechanics. The sensors have to aim to give objective data on ligaments balancing during TKA. Few studies are published on the results at mid-term of these two devices currently. The accelerometers are smart tools developed to improve the TKA alignment. Their benefits remain yet controversial. The robotic-assisted systems allow an accurate and reproducible bone preparation due to a robotic interface, with a 3D surgical planning, based on preoperative 3D imaging or not. This promising system, nevertheless, has some limits. The new technologies in TKA are very attractive and have constantly evolved. Nevertheless, some limitations persist and could be improved by artificial intelligence and predictive modeling.

Keywords: accelerometers; customized implants; knee arthroplasty; new technologies; patient-specific instrumentation; robotic-assisted surgery; sensors.

Figure 1

In the patient-specific instrumentation, the personalized cutting guides can be pinned directly into place in the femur and the tibia and contain cutting slots for a saw.

Figure 2

The sensor is an articular loading quantification device, which is inserted in the tibial component tray during the surgery, after the tibial and femoral cuts are completed (Orthosensor, Verasense).

Figure 3

The accelerometer is a handheld device used within the operative field to determine the resection planes of the proximal tibia. This system guides resection angles in the coronal and sagittal planes (Perseus, Orthokey).

Figure 4

The autonomous and semiautonomous robotic systems incorporate safeguards against removal of bone beyond the 3D plan. The first three robotic systems are autonomous (Robodoc, Caspar). The last three robotic systems are semiautonomous (Mako, Navio, Rosa).

Figure 5

Per operative pictures and radiographs of a medial unicompartmental arthroplasty associated to a patellofemoral replacement in a young and active patient.