TECHNOLOGY IN MEDICINE
USE OF ROBOTIC-ASSISTED SURGERY
IN TOTAL JOINT ARTHROPLASTY
AUTHORS Austin Smith, MD, Logan Mast, MD, Madhusudhan Yakkanti, MD, & Arthur Malkani, MD
Arthroplasty of the hip and knee are highly successful
operations in providing pain relief and restoring function
in patients with end-stage arthritis and disabling pain. The
number of patients undergoing total joint replacement
is set to increase in the coming decades due to multiple
factors. These include aging of the “baby boomers,” longer
lifespans and higher functional demands at later ages (e.g.
octogenarians). More people than ever are obese. Indications for
these procedures have expanded related to technologic advances
over the past decade which have increased the lifespan of these
total joint implants. 1
The success of hip and knee arthroplasty is judged by
postoperative function, patient-reported outcomes such as pain and
satisfaction, and implant survivorship. Today’s health care system
continues to place greater emphasis on patient-reported outcomes
and satisfaction. Those statistics range widely. In one study, 19%
of patients undergoing total knee arthroplasty (TKA) were not
satisfied with their outcomes. 2,3 In another, a final year follow-up
study of 384 unicompartmental or partial knee arthroplasty patients,
91% of patients were either very satisfied or satisfied with their
knee function. 4 There are several reasons for patient dissatisfaction
following TKA including component malalignment, instability,
contracture and not meeting patient expectations. 5 Malalignment
of the implants has been identified in 32% of conventional TKA’s
and can lead to symptoms of pain and instability. 6 “Instability with
clinical symptoms of pain and effusion due to ligamentous imbalance
from flexion and extension gap mismatch” following TKA is the
second leading etiology of failure of a primary TKA. Prosthetic joint
infection is the most common cause of second or third procedures
after total knee replacement. 7,8
12 LOUISVILLE MEDICINE
The ability to achieve the desired overall limb alignment and soft
tissue gap balancing of the flexion and extension gaps with accuracy
and reproducibility using hand held saws and manual jig based
cutting guides can be challenging. Manual jig-based instruments
have demonstrated variability and inaccuracy during primary
TKA (Figure 1). The surgeon has to machine the distal femur and
proximal tibia using cutting guides and measurement blocks/laminar
spreaders to gauge the accuracy of the flexion and extension gaps.
Recent advances in technology have led to the use of robotic-assisted
surgery in the field of orthopedics to help surgeons obtain more
accurate and reproducible results for total joint arthroplasty. The use
of 3D-based computer software and robotic technology has been
shown to be effective in many industries. In 1985, the first surgical
application of industrial robotic technology was described when
an industrial robotic arm was modified to perform a stereotactic
brain biopsy with 0.05 mm accuracy. 9 Since then robotic-assisted
technology has been used widely in neurologic, cardiac, gynecologic,
urologic and now more recently, orthopedic surgery. 10,11
Robotic-arm assisted surgery for total knee arthroplasty provides
surgeons the ability to develop a 3D preoperative plan to obtain
the desired limb and component alignment along with soft tissue
balancing with gap measurements in 1 mm increments for the
1a
Figure 1 a,b) Intraoperative images of manual jig-based cutting guides
for distal femoral resection and proximal tibial resection used with handheld
saws during total knee arthroplasty.
Images courtesy of Douglas A Dennis, MD, Reconstructive Review, JISRF,
Chagrin Falls, Ohio.
1b