Robotic-arm assisted total knee arthroplasty demonstrated soft tissue protection76

Intro

  • Six cadaver knees were prepared using RATKA by one surgeon from mid- to high-volume TKA joint centers with no former clinical robotic experience and compared to seven manually performed cases. A single surgeon from a high-volume TKA joint center, who had no prior clinical robotic experience, prepared six cadaver knees using robotic-arm assisted TKA (RATKA) and seven cadaver knees using manual TKA (MTKA).
  • The presence of soft tissue disruption was assessed by having an experienced surgeon perform visual evaluation and palpation of the PCL, MCL, LCL, and the patellar ligament after the procedures. In addition, leg pose and retraction was documented during all bone resections. The amount of tibial subluxation and patellar eversion was recorded for each case.

Results

  • For all RATKA cases, there was no visible evidence of disruption of any of the ligaments.
  • All RATKA cases were successfully left with a bone island on the tibial plateau, which protected the PCL (example cadaveric specimen and corresponding tibial implant plan shown in Figure 1).
  • In a cadaveric model, Mako Total Knee demonstrated soft tissue protection.
Total Knee Clinical Evidence
Total Knee Clinical Evidence
Figure 1: A) Manually performed TKA with arrow pointing to PCL, with no bone island preparation. B) Robotically performed TKA, with bone island preparation in front of PCL and corresponding tibial view from Implant Planning page (showing implant plan to the actual boney anatomy, with remaining bone island). Black arrow points to PCL. White arrows outline bone island.

Stereotactic boundaries help protect the cutting tool from injuring soft tissues; however, patient anatomy, implant plan, and surgeon specific techniques are variable. The surgeon is responsible for properly retracting soft tissues during bone resection, including but not limited to: collateral ligaments, patellar tendon, quadriceps mechanism, and PCL.


Robotic-arm assisted total knee arthroplasty demonstrated greater accuracy to plan compared to manual technique76

Intro

  • Six cadaveric specimens (12 knees) were prepared by a high-volume TKA surgeon, who had no prior clinical robotic experience. For each cadaveric pair, a RATKA was prepared on the right leg and a MTKA was prepared on the left leg.

Results

  • In a cadaveric model, Mako Total Knee demonstrated accuracy of TKA final bone cuts and final component placement to plan, even for an experienced user of manual instrumentation who is new to robotic technology.
Total Knee Clinical Evidence Total Knee Clinical Evidence

Figure 2: Area plot showing stacked results for all (a) final bone cut and (b) final component placement error to plan for manual (MTKA) and robotic (RATKA). The x-axis of both graphs lists the identification of the specimens in procedural sequence from the first procedure to the last procedure.