OrthAlign chooses ADI's iMEMS motion sensor for portable surgical navigation system

26 September 2012

Analog Devices has announced that OrthAlign has selected ADI’s high-performance iMEMS inertial motion sensing technology for its new portable surgical navigation system that guides femoral alignment during knee surgery.

The KneeAlign 2 System, which also provides precise tibial alignment, uses an ADI iSensor digital IMU (inertial measurement unit) to allow an orthopaedic surgeon to quickly determine the centre of rotation of a patient’s femur and calculate the precise angles to cut the bone in knee replacement surgery.  

The compact KneeAlign 2 System combines the alignment precision of large, computer-assisted surgical equipment with the simplicity of conventional instrumentation. The palm-sized KneeAlign unit and its associated cutting instrumentation are compatible with all implant systems used in TKA (total knee arthroplasty), a surgical procedure in which pieces of the knee are replaced with artificial parts.

“Successful TKA surgery depends on accurate knee alignment,” said Patrick O’Doherty, vice president, Healthcare Group, Analog Devices. “By using an ADI iSensor IMU, the KneeAlign 2 provides alignment precision comparable to the larger, significantly more expensive camera-based navigation systems, which are shown to result in knee replacement alignment outcomes of 91% accuracy compared to 68% accuracy using conventional mechanical surgery. As the patient’s knee is put through a full sweep of motion, the surgeon relies on the positioning and dynamics captured by the IMU to quickly determine the precise orientation of the femoral cutting block.”

“Analog Devices’ iSensor IMU played an instrumental role in making the design of the KneeAlign 2 System possible,” said Darius Kharabi, OrthAlign’s vice president of Corporate Development. “This month we completed our limited use release of approximately 50 TKA surgeries using the KneeAlign 2 for both femoral and tibial navigation in highly regarded knee surgery centres across the United States, and the results are extremely encouraging. We plan to launch the KneeAlign 2 System in the first quarter of 2012, while continuing clinical studies at the Hospital for Special Surgery in New York, Scripps Green Hospital in California and other centres of excellence.”

According to the Agency for Healthcare Research and Quality, approximately 675,000 Americans underwent knee replacement surgery in 2009. And it is estimated that this procedure will be performed on 3.5 million in 2030. Currently, an estimated 30% of all TKA procedures result in poor implant alignment.

 

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