In pediatric populations it is challenging to monitor the success of a bone fusion procedure. The objective of this project was to develop Microelectromechanical Systems (MEMS) sensors that will measure local mechanical strain as a readout for bone fusion progression, such as a spinal implant. Established sensor technology was re-engineered for optimal size and sensitivity in a preclinical small animal model of bone repair. Long-term outcomes from these studies will establish the ability of the strain sensor to monitor bone fusion. This minimally invasive monitoring system would let doctors evaluate the progress of a spinal fusion in pediatric patients without costly imaging techniques which expose the patient to unnecessary radiation.