Feasibility of Portable Acoustic Emission Approach for Prognosis of Stress Fractures

Repetitive mechanical loading induces microscale damage in bone to accumulate and may lead to stress fractures [1]. People with weakened bones due to disuse or disease, or, healthy people who have excessive exercise regimes (soldiers and athletes) experience these fractures [2]. Stress fractures interrupt training, reduce fitness and may even lead to discharge from the military in certain occasions [3]. Therefore, early prognosis and prevention of stress fractures would be desirable. Currently, following methods are being used for diagnosis: plain radiography, computed tomography (CT), bone scintigraphy and magnetic resonance imaging (MRI). The sensitivity of plain radiography is very low, 15–35% [4]. CT is less sensitive than radiography except some very special and rare cases of stress fractures [5]. Among these diagnostic methods, scintigraphy and MRI are more sensitive. However, the former lacks specificity because it may confound infections, tumors, bone infarctions, periostisis and osteonecrosis [2,5]. Furthermore, it is radioactive [5]. MRI has immense economical and logistical limitations [6].