Hundreds of thousands of Americans receive knee replacement surgery each year as Baby Boomers age and strive to remain active.

While prosthetic knees are expected to last as long as 20 years, the failure rate due to improperly balanced replacements or post-operative infection is a serious concern, since do-overs cause patients additional suffering and are more costly than the original operation.

Improve outcomes

OrthoSensor, a small company based in Sunrise, has developed a high-tech device that provides real-time data to orthopedic surgeons during knee replacement surgery and could help improve outcomes and reduce failure rates in this increasingly common operation.

The four-year-old company, which so far has raised $42 million in venture capital, is also advancing work on other implantable devices for orthopedic patients, including tiny units that electronically transmit data to physicians and nurses on internal temperature, blood acidity levels and other indicators that can be used to detect infections following orthopedic surgeries, as well as implants that send out sound waves to assess bone density.

“Our lives have been transformed by new technology in computer programming, cell phones, the Internet and miniaturization,” said Jay Pierce, the company’s president and CEO. “Everything is getting smaller. We have combined advanced technology, wireless communications, sensors and microelectronics to produce ‘intelligent orthopedics,’ devices that improve outcomes in musculoskeletal disease and reduce healthcare costs,” said Pierce, who has worked in the medical device, technology and communications sectors for more than 27 years.

The company’s first product, the OrthoSensor Knee Balancer, contains sensors that help orthopedic surgeons properly balance a knee implant by transmitting data over a wireless system to a computer screen during the operation. Using this data on the screen, they can make adjustments to soft tissue around the knee and optimize implant placement.

The goal of this device, now being used in trials by 30 hospitals and orthopedic teaching centers in Florida, New York, Michigan and 12 other states, is to achieve extremely accurate implant placement that will improve function of the new knee and reduce the need for costly revision surgery.

The knee balancer, which costs about $500 and is made in Phoenix, is used only once and then discarded to avoid the possibility of infection. It received approval from the U.S. Food and Drug Administration in late 2010 and took about two years to develop.

Before the OrthoSensor Knee Balancer was available for trials earlier this year, surgeons relied on their knowledge, experience and the “feel” of the implant and the patient’s leg to decide if a new knee was properly balanced.

“When we do knee replacements today, surgeons make their cuts, plant the prosthesis and then test how the prosthesis feels in their hands. That is the art to the procedure,” said Dr. Martin Roche, chief of orthopedics and director of the Holy Cross Orthopedic Institute in Fort Lauderdale, who developed the idea for the knee balancer and founded OrthoSensor in 2008.

‘Optimum result’

“If one of the ligaments on each side is tight or loose, that is judged by the surgeon as he tensions and sees how the knee moves,” added Roche, who trained at the University of Miami and has been working in joint replacement at Holy Cross for the last 15 years. “With OrthoSensor, we’re integrating sensor technology into the trials, so now I can quantify how tight or how loose I am in that patient’s knee joint. This allows me to loosen or tighten ligaments, change the rotation of the implants or use different thicknesses in the bearings to obtain the optimum result.”