uses a 3D printer to create a sterilized mold that is customized to that
patient's specific anatomy. This mold then fits directly onto the
patient's bone during their operation, and incorporates all the plan-
ning and sizing data into a guidance system. This customization
allows the surgeon to make precise cuts to the bone that utilize all the
data analyzed and inputted during the digital planning. All of this
translates into an operation that is more accurate, less invasive and
more efficient than many of its predecessors.
Some studies have shown that patient-specific instrumentation in
total knee replacement not only decreases operative time, but also
improves the accuracy of bone cuts, resulting in a more rapid recov-
ery that leads to earlier discharge. While this innovation is not yet
widely available for hip replacements, there are other modalities and
technologies that are allowing for improvement in that space.
• Robotic assistance. Another enabling surgical technology we use
for both hip and knee replacements is robotics, which allow us to do
much of the same type of patient-specific planning, but also offers the
flexibility to adjust in real time. Preoperative imaging is used to gener-
ate a three-dimensional plan on a computer. During surgery, we use a
robot arm to help execute those plans.
• Optimized implants. The manufacturers we work with have
evolved to develop longer lasting implants with better kinematic
capabilities. For example, there is a great deal of focus on reproduc-
ing a more natural and normal arc of motion when replacing the
knee joint. Your native knee is not a simple hinge joint that bends
back and forth. Instead, as you go from extension to flexion and
back again, numerous subtle rotational movements occur around
the joint — in addition to and in conjunction with the simple hinge-
type bend. If the replaced knee cannot mimic these more subtle and
natural movements, it's possible the patient will be less satisfied
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