Kinematically aligned Knee Replacements using patient specific instruments
There have been many advances in total knee replacements, from the implants themselves to the technology used to implant them. These have led to shorter hospital stays, less blood loss, more patients reporting good or excellent knee function, and more accuracy for the surgeon in component placement.
Historically we aimed to give everyone a completely straight leg, regardless of what alignment they were born with. This was to accommodate the knee replacement and the loss of some of the ligamentous supports that come about due to knee replacement surgery. Mechanical Alignment (MA) aimed to restore a straight line from hip to knee to ankle. A newer concept is that of Kinematic Alignment (KA), and this is the approach that Dr Host favours. In KA knee replacements, the thickness of the implants being inserted is removed off the ends of the bone as a resurfacing of the joint, leaving the knee in its natural alignment. By doing this, we do not alter the natural position of the ligaments, muscles, and capsule around the knee – in essence, you put the knee back where it was when you finished growing. This technique has been shown in studies to lead to improved patient satisfaction scores post knee replacement surgery.
Kinematic Alignment is determined for each patient using fine-slice 3D CT scans of the leg, Artificial Intelligence software to determine a rough plan, and the plan is finalised between the Medacta engineers and Dr Host. One a plan is confirmed, 3D custom cutting guides are constructed giving each patient their own specific set of instruments for use during your surgery. This allows us to customise the surgery for each patient, and accurately deliver the plan on the day.