TECHNOLOGY IN MEDICINE
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2a
Figure 2a) Preoperative antero-posterior and lateral x-rays
demonstrating right knee osteoarthritis in a 64-year-old male who has
failed non-operative treatment.
individual patient. Robotic-assisted bone cuts and implant placement
in the coronal, sagittal and axial planes can be accomplished to
within 1 mm accuracy to match the patient’s anatomy and obtain
precisely balanced gaps and the desired overall alignment and
component position specific for the individual patient. In addition,
real time intraoperative information is available to confirm the target
alignment and desired gap measurements with the ability to make
any necessary intraoperative changes to achieve the desired target
goal. Figure 2 shows preoperative and postoperative radiographs
of a TKA performed with robotic-arm assisted surgery along
with intraoperative computer 3D images allowing for real time
manipulation of the bone cuts and implant placement to best match
the target alignment for the individual patient’s unique anatomy.
The surgeon cannot by eye alone measure the multiple planes and
contours of a knee – that must flex and extend by many degrees –
even with perfectly machined instruments. The robotic system can
make the measurement and guide the surgeon correctly to the spot,
for each cut in the exact plane (Figure 3).
Early outcomes related to the use of computer technology and
robotic-assisted TKA versus manual or jig based conventional TKA
have been studied. 12–14 The Feb. 2020 online publication designed
here at UofL showed that robotic-assisted TKA has been associated
with decreased pain and postoperative opioid use, improved
early functional recovery and reduced time to hospital discharge
compared to conventional jig-based TKA. 13,15 Similarly, improved
patient satisfaction has also been demonstrated with robotic-assisted
TKA. 16 Further, several studies including a meta-analysis and a small
prospective randomized trial have shown superior alignment and
balancing with robotic-assisted surgery versus the use of manual jig
based cutting sides and hand held saws. 12,17,18 In addition to TKA,
robotic-assisted surgery has also demonstrated improved result
with unicompartmental or “partial” knee replacement (Figure 4). 4
Improved results have also been demonstrated with roboticassisted
total hip arthroplasty (THA) compared to the use of manual
instruments. A recent study in the Journal of the American Academy
of Orthopedic Surgeons compared five-year outcomes of roboticassisted
THA to manual THA and showed improved outcomes in the
robotic-assisted group including better patient-reported outcomes,
better positioning of the acetabular implant component and more
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2d
Figure 2b) Computer image of virtual preoperative plan to obtain size,
implant position and soft tissue balancing using 3D software which can
be manipulated intraoperatively to help achieve the target goal.
Figure 2c) Real time intraoperative image demonstrating TKA
components placed in the target position with soft tissue gaps balanced
within 1mm following insertion of the final implants.
Figure 2d) Postoperative antero-posterior and lateral images 1-year
following robotic-assisted TKA with well-fixed and well-aligned implants
with return to function and excellent pain relief in this 64-year-old male.
accurate leg length and global offset. 19 With robotic-assisted total
hip arthroplasty, the surgeon is able to place the implants to match
the patient’s native anatomy, especially the hip center and leg length.
The 3D CT based software measurements are much more refined
than using manual instruments, which rely on the surgeon’s ability
to identify bony landmarks (Figure 5).
The use of robotic-assisted surgery is becoming more widespread
in all surgical fields. Robotic-assisted surgery provides several
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