Optical Sensing for the Assessment of Bone Fracture Healing Progression in External Fixator Mediated Stabilization

Monitoring the progression of bone fracture healing is essential for successful clinical outcomes. Conventional X-ray imaging involves repeated radiation exposure, necessitating frequent and radiation-free evaluation techniques. Interfragmentary strain (IFS) is a key biomechanical marker of healing progression. This study proposes a non-invasive optical instrumentation for monitoring fracture healing via IFS measurement. An ex vivo tibial fracture stabilization model was developed using Agilus elastomer callus replicas of varying stiffness. Fiber Bragg Grating (FBG) sensors mounted on Schanz pins measured strain under controlled axial displacement. Results demonstrated reduced strain with increasing callus stiffness, establishing a non-invasive and radiation-free assessment of fracture consolidation.