Louisville Medicine Volume 68, Issue 1 | Page 14

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