Robotic-assisted TKA Reduces Postoperative Alignment Outliers and Improves Gap Balance Compared to Conventional TKA

Abstract

Background Several studies have shown mechanical alignment influences the outcome of TKA. Robotic systems have been developed to improve the precision and accuracy of achieving component position and mechanical alignment. Questions/purposes We determined whether roboticassisted implantation for TKA (1) improved clinical outcome; (2) improved mechanical axis alignment and implant inclination in the coronal and sagittal planes; (3) improved the balance (flexion and extension gaps); and (4) reduced complications, postoperative drainage, and operative time when compared to conventionally implanted TKA over an intermediate-term (minimum 3-year) followup period. MethodsWe prospectively randomized 100 patients who underwent unilateral TKA into one of two groups: 50 using a robotic-assisted procedure and 50 using conventional manual techniques. Outcome variables considered were postoperative ROM, WOMAC scores, Hospital for Special Surgery (HSS) knee scores, mechanical axis alignment, flexion/extension gap balance, complications, postoperative drainage, and operative time. Minimum followup was 41 months (mean, 65 months; range, 41-81 months). Results There were no differences in postoperative ROM, WOMAC scores, and HSS knee scores. The roboticassisted group resulted in no mechanical axis outliers ([ ± 3°from neutral) compared to 24% in the conventional group. There were fewer robotic-assisted knees

Patient-specific Guides Do Not Improve Accuracy in Total Knee Arthroplasty: A Prospective Randomized Controlled Trial

“…Some surgeons use tensioned gaps in addition to the measured resection to position the implants [11,12]. Postoperative malalignment is reported in a significant number of patients when these conventional instruments are used [4,14,26,35,36].…”

Early experiences with robot-assisted total knee arthroplasty using the DigiMatch™ ROBODOC® surgical system

“…(4)(5)(6)(7)(8)(9) Its ability to achieve precise component implantation can be attributed to four factors. First, unlike conventional surgery where a fixed resection angle (i.e.…”

“…(3) In contrast, robot-assisted TKA promises excellent implant positioning and alignment, with errors within 1-3 degrees of neutral alignment. (4)(5) Other than excellent implant positioning and alignment, robot-assisted TKA has also been shown to consistently yield: (a) ideal postoperative mechanical alignment through individualisation of the distal femoral resection angle; (b) accurate rotational alignment of the femoral component; (c) accurate machining of bone surfaces with a milling device; and (d) good maintenance of bone temperature during machining, preventing bone injury. These characteristics may lead to reduced implant wear rates, and thus, longer prostheses survivorship.…”

Robotics accuracy in orthopaedics: is it enough for a well-working knee replacement?

“…Published papers about robotics in knee replacement, both prospective and retrospective with or without a control group, usually agree on better radiological outcomes in terms of alignment and implant positioning (6,7). Major complications are rarely reported in primary joint replacement surgery (either with or without the use of robots) and clinical benefits of the use of the robotics are not so evident.…”