Why Use Robotic-Arm Assisted Knee Replacement Technique?

Knee replacement surgery has become the most commonly replaced major joint in the United States. Most all types of arthritis eventually end with bone-on-bone changes, knee pain, reduction of activity and loss of quality of life. Even with those disabling issues, a dissatisfaction rate among some patients that have had knee replacements remains. For this reason, techniques to improve the surgery have continued to progress. Robotic-arm assisted surgery began approximately 10 years ago with a partial knee replacement, and total knee replacement became available approximately four years ago. 

There are two main areas of focus when correctly performing knee replacement surgery: The bone cuts and the soft tissue balance. The robot performs the bony cuts very accurately and gives guidance to the soft tissue balancing. My early experience in the lab indicated that even though the robotic information showed that the knee I had just replaced (on a cadaver) was balanced, my manual assessment didn’t support that the knee was perfectly balanced. This slowed my adoption due to wanting the final “feel” and stability, dependent on the soft tissue balancing, to be effected by my expertise in achieving a perfectly balanced knee. Software was developed, and in use, that allows me to perform the knee replacement in the very same sequence, with manual checks after each phase of the operation, just as I would in a standard manual or non-robotic case. Best of both worlds.

Advantages of Using Robotics: 

  • Soft tissue protection:  A robotic assisted knee replacement begins with the patient getting a CT scan of their knee and lower extremity. The scan is then imported into the brains of the robot. At surgery, the knee is opened and the anatomy carefully mapped and mated to the CT scan. The robot arm or saw is then brought into the field and the bony cuts are performed. The advantage, and this is important, is that the saw is now guided by the combined information. The precise location of the saw will not damage soft tissue. This allows the surgeon to access more gently, with the hope that there is less damage, less bleeding, and hopefully a quicker, less painful recovery. The robot is also gentler to the patient’s bone as no guide pins are needed to secure cutting blocks.
  • Sizing:  From a surgeon’s point of view, the robot allows for very precise surgical planning. The size of the patient’s tibia (leg bone) and femur (thigh bone) is known, and the correct size implants can be planned. Throughout my career I have encouraged implant companies to add more offerings so that varying patient anatomies can be accommodated. In the planning stage, there are various techniques to accommodate even the in-between sizes and mismatches of femur and tibia that are frequently seen.
  • Fine tuning adjustments:  My entire career has been focused on precision-fine tuning the bone and soft tissue to exactly balance and restore a patient’s knee to full function.  With the proper attention to detail, subtle adjustments can be made, without drilling additional pins into the patient’s bone during the case, to place the components accurately and obtain ideal soft tissue balance. An experienced surgeon utilizing high level imaging and computer led robotic technology, acts as a very proficient tool in terms of micro level precision.