Gyroscopes, wi-fi used for better knee surgery

Gyroscopes that keep aircraft steady and smartphones facing the right way, and wi-fi for wireless Internet use, are integrated in a new technique introduced in Jerusalem to replace damaged knee joints.

Prof. Meir Liebergall, chairman of the department of orthopedic surgery at Hadassah University Medical Center in Jerusalem, was part of a team that performed four such knee replacement operations, among only a small handful in the United States, Canada and Germany.

Liebergall, a leading expert in computer-guided surgery on hips and other parts of the body, was a member of a very small clinical advisory group to the American company that developed the technology.

Called iAssist Knee, the personalized guidance system for knees was developed by the Zimmer Holdings company, a world leader in developing technologies and tools for orthopedic surgery, based in Warsaw, Indiana.

The small gyroscope in the device enables surgeons to accurately situate the bone at the proper plane and provides them with the precise angle for the incision. The wi-fi component makes possible communication between the tool on the patient’s knee bone and the operating room computer.

Together, the gyroscope and the wi-fi give surgeons maximum accuracy, resulting in less blood loss for the patient, faster recovery and the use of much less equipment. Under the old system, dozens of devices are used to perform such surgery.

Leibergall performed the surgery at the Mount Scopus Hadassah University Medical Center with Dr. Yoav Mattan (director of Hadassah’s joint replacement unit) and their colleagues Dr. Gurion Rivkin and Dr. Leonid Kandel.

Weak-kneed patients needing such surgery are typically over the age of 60 and/or obese.

The unit performs more joint replacements of all kinds than any other Israeli hospital, with 700 such operations already carried out, 250 of them knee replacements using the previous technology. The International Society for Computer- Assisted Orthopedic Surgery has designated Hadassah’s department as a Center of Excellence for its accomplishments and its innovative use of new technologies and surgical tools.

In 2004, Liebergall and Mattan performed the world’s first computer-assisted hip replacement, then too using Zimmer technology.

“iAssist is yet another step forward in the advancement of computer-assisted orthopedic surgery,” said Liebergall.

“We are proud that Hadassah continues to play such a pivotal role and that internationally recognized leaders in the field such as Zimmer launch their flagship products at Hadassah. It makes the surgeon’s work more accurate and with a better outcome,” said Liebergall.

“Two years were spent developing the prototype,” Liebergall told The Jerusalem Post. “The new technology does not require a straight line of site between the components.”

He doesn’t know what the eventual price of such surgery would be, or when it would be included in the basket of health services.

“But it will save a lot. At present, Zimmer’s cost includes the costs of development, but it will go down.”

The Hadassah orthopedic surgeon added that some of his colleagues are reluctant to use computer-guided equipment because they don’t feel very comfortable when their hands are not touching the patient. This advance could break down this reluctance among them, he said.

No medical journal articles have been published proving efficacy and improvement compared to previous techniques, Liebergall said, “because it is so new. But I believe it is definitely the future or joint replacement surgery.”

Despite the lack of organized scientific research, the US Food and Drug Administration has awarded clearance to Zimmer Holdings to market iAssist Knee.