Future TJR could be linked to navigation, robotic assistance

Three-dimensional laser scanning could detect defects in the femur, aid in choosing implants.

Issue: Issue 6 2008

In an attempt to improve precision and individualize patient care, some surgeons are looking to computer navigation and robotics for total joint replacement.

At the 9th Annual Advances in Arthritis, Arthroplasty and Trauma Course, Michael J. Fracchia, MD, and Frank Lampe, MD, discussed the latest developments in robotics and computer navigation. “Navigation has opened up a whole new world” Fracchia said. “The recording of real-time objective data will help us with the design, implantation and longevity [of implants].”

Fracchia noted that German researchers are using ultrasound to define the anterior pelvic plane, and he said that the technology could be used in a similar way to aid surgeons performing minimally invasive total knee arthroplasty (TKA).

Surgeons may also incorporate the 3-D laser scanning techniques that are currently used in the automotive industry. “You could look at the anteversion in the cup if you had a 3-D laser image,” Fracchia said.

Damaging reports in the media, unfavorable scientific results and a leading court decision noting a higher incidence of complications in robotic-assisted surgery has caused modified industrial robots to vanish from German operating rooms. However, Lampe said that he believes these systems will return if they are time- and cost-effective and safe.

The modiCAS is one robotic system designed for total hip arthroplasty.

Image: modiCAS Ltd.

Robotic types

“In my opinion, they should be passive or semi-active, rather than active autonomous systems, and they should provide additional benefits compared to pure navigation,” he said.

He noted that robotic systems can be classified into the following categories:

active, in which the robot executes segments of the procedure;
semi-active, where the surgeon performs the operation, but is guided by the robot; and,
passive, in which the robot does not actively execute any segment of the operation.

Many companies are developing robotic surgical systems for TJR. Lampe said the modiCAS (modiCAS Ltd.) is a semi-active system developed for total hip arthroplasty. Optical navigation tracks the patients and no patient fixation is necessary. Researchers in Germany are conducting a clinical trial using the system for cup implantation, Lampe said.

More systems

The Acrobot Sculptor (Acrobot), a hands-on, semi-active system, is undergoing clinical investigation for unicondylar knee arthroplasty (UKA).

Similarly, the Makoplasty (Mako Surgical Corp.) system is semi-active and developed for UKA. The surgeon performs bone sculpting using a burr, but receives tactile guidance from a robotic arm.

The Bone Resection Instrument Guide (BRIGIT, Zimmer) is a passive system used for TKA. “The only thing that the robot does is position manual cutting guides, and then the cutting is performed manually by the surgeon,” Lampe said.

Meanwhile, American researchers from Carnegie Mellon University have developed the miniature, bone-attached robotic system (MBARS) for patellofemoral joint replacement.

“[It] is a small bone-mounted, active mini-robot using the parallel hexapod technique,” Lampe said. “No preoperative planning is carried out and no patient tracking is necessary because it is fixed to the bone.”

In addition, the Praxiteles (Praxim, Medivision) system is a bone-mounted, passive, mini robot developed for MIS TKA. The system also uses a bone-milling technique that incorporates a passive guide and side-milling tool, Lampe said.

For more information:

Michael J. Fracchia, MD, can be reached at Long Island Bone & Joint LLP, 635 Belle Terre Road, Suite 204, Port Jefferson, NY 11777, U.S.A.; +1-631-474-0008; mfracchia@libones.com. He receives royalties, consulting fees and fees for non-CME from Aesculap, and royalties from Innomed.

Frank Lampe, MD, can be reached at the Joint Replacement Center, Klinikum Eilbek-Schoen Kliniken, Dehnhaide 120, D-22081 Hamburg, Germany; +49-89-6211-0; e-mail: lampe@ortho-hamburg.de. He is a member of the B. Braun/Aesculap speakers’ bureau.

Reference:

Lampe F. TJR in 2018. Fracchia MJ. TKA navigation in 2018. Both presented at the 9th Annual Advances in Arthritis, Arthroplasty and Trauma Course. Sept. 10-12, 2008. Arlington, U.S.A.