OrthoAlign Case Study
OrthoAlign's Palm-sized KneeAlign® 2 System Uses Analog Devices' iSensor Inertial Measurement Sensing Technology to Provide Surgical Precision —
Recent innovations in computer-assisted surgery are pushing the boundaries of modern medicine to new and exciting frontiers. As conventional surgical instrumentation continues to give way to advanced console- and camera-based systems, surgeons are able to operate on patients with exceptional precision.
The design team at OrthAlign is taking this innovation trend one step further with the recent introduction of its KneeAlign® 2 System, a palm-sized surgical navigation system for precise tibial and femoral alignment during total knee replacement surgery. Rather than employ camera-based navigation, which adds significant expense and size to a surgical navigation system, OrthAlign's design team counts on an ADI iSensor® IMU (inertial measurement unit) to enable an orthopedic surgeon to determine within seconds the center of rotation of a patient's femur and calculate the precise angles to cut the bone during knee replacement 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 ADI IMU to quickly determine the precise orientation of the femoral cutting block.
The ADI iSensor IMU designed into the KneeAlign 2 System provides six-degrees-of-freedom measurement via three accelerometers and three gyroscopes that sense linear motion and angular motion, respectively. The iSensor IMU is capable of precisely tracking an instrument's motion on all axes, even during demanding operating conditions. The compact IMU device provides access to both calibrated and dynamically compensated sensor data over a standard digital SPI interface, and offers the ability to digitally tune the sensor filtering and processing to adapt to multiple application scenarios. The availability of precise inertial data over a simple digital interface, out of the box, allowed the OrthAlign design team to save years of development time in bringing this revolutionary product to market.
With the ease of use available from traditional instrumentation, OrthAlign's KneeAlign 2 System has received 510(k) clearance from the FDA (Food and Drug Administration) as being substantially equivalent to camera-based, large-console computer-assisted surgery systems for tibial and femoral measurement. These larger, significantly more expensive and complex systems have been shown to result in knee replacement alignment outcomes of approximately 91 percent accuracy, compared to 68 percent accuracy yielded via conventional, mechanical surgery.
With U.S. demand for TKAs (total knee arthroplasties) expected to climb 673 percent from 2005 to 2030, OrthAlign's continued innovation in the field of knee surgery, enabled in part by ADI's iSensor technology, is significant for surgeons and patients alike.
|"ADI's iSensor inertial measurement technology plays a critical role within our KneeAlign 2 System, and equipped our design team to achieve aggressive precision, form factor and cost targets."
Darius Kharabi, vice president of Corporate Development, OrthAlign, Inc.