Imaging of tendons and ligaments in animal models

There are many viable options to image tendons and ligaments. Depending on the structure under view, ultrasound, magnetic resonance imaging (MRI), light microscopy, fluorescence microscopy (FM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (X-ray-D), atomic force microscopy (AFM), or second-harmonic generation (SHG) is used. For macroscopic investigations including anatomical questions, ultrasound and MRI are preferred imaging methods, while for smaller entities such as fiber bundles, fascicles, or tenocytes, light microscopy, FM, and SEM are in use. Finally, on the collagen molecule level, X-ray-D, TEM, AFM, or SHG are the methods of choice. In this chapter, each methodology is introduced with respect to the physical background, and its application demonstrated in a large variety of reports dealing with tendon and ligaments. A special focus is set on biomechanical measurements based on imaging methods.