Following an orthopedic procedure, surgeons usually rely on X-rays or MRIs to monitor the progress of their patients' recovery. A new implantable sensor developed at Rensselaer Polytechnic Institute could provide surgeons with detailed, real-time information from the actual surgery site in a more accurate and cost-effective manner. Access to these data could lead to more accurate assessments of a patient's recovery, or provide better insight into potential complications.

The wireless sensor measures only 4 millimeters in diameter and 500 microns thick. It does not require a battery, external power, or electronics within the body. Instead, it is powered by the external device, which is also used to capture the sensor data.

The sensors look like small coils of wire and are attached to commonly used orthopedic musculoskeletal implants such as rods, plates, or prostheses. Once implanted in the in vivo environment, the sensor can monitor and transmit data about the load, strain, pressure, or temperature of the healing surgery site. The sensor is scalable, tunable, and easy to configure so that it may be incorporated into many different types of implantable orthopedic devices.

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Also: Implantable electrochemical sensors are being developed for metabolic monitoring of diabetic patients.