Ligament injuries are common especially among young physically active people and significantly increases risk for post-traumatic osteoarthritis later in life.

Restoring knee musculoskeletal function through ligament reconstruction surgeries is currently a major challenge. Technologies to enable gaining information of ligament function could have major impact of ligament diagnostics and reconstruction.
Previous studies with near infrared spectroscopic measurements of bovine ligaments and tendons have shown a promise to indirectly gain information of biomechanical properties. Therefore, we aimed to implement mid-infrared (MIR) spectroscopy to investigate the structure-function relationship in a ligament injury model.

Collateral ligaments were extracted from six rabbits after anterior cruciate ligament transection (ACLT) eight weeks after surgery. Four rabbits were used as controls. MIR spectra from ligament was compared against biomechanical properties. Our results indicated that MIR spectra contain information on the viscoelastic mechanical properties of the ligaments.

The novel MIRACLE probe demonstrated potential to be used in reconstruction surgeries to assess ligament and this will be a step forward in arthroscopic evaluation of knee ligaments condition. However, further experiments will be done in 2021 involving human samples to enhance the method accuracy.