Image fusion of computed tomographic and magnetic resonance images for the development of a three-dimensional musculoskeletal model of the equine forelimb.

The research is centered on making a three-dimensional model of a horse’s forelimb using both CT and MRI scans. The focus of the study is largely applicable in studying factors that prompt injuries and planning orthopedic surgeries.

Objectives and Methodology

• The primary aim of this research is to devise a 3D general model of a horse’s forelimb, focusing on its bones, muscle-tendon units, and ligaments. The researchers relied on high-resolution CT and T1-weighted MR images from a Thoroughbred racehorse’s detached forelimb.
• The fusion of images was attained by co-registering the CT and MR images through an image analysis software called Analyze. The software allowed adjustments in the position and orientation of tangible markers noticeable in both imaging modalities until the mutual data between the images was amplified.
• The multimodal images (CT/MR) after fusion were then made use of to derive 3D outlines of the bones and source/attachment sites, paths from the center and volumes of the muscle-tendon and ligamentous structures. The researchers used semi-automated and manual segmentation combined with sagittal and transverse color-cryosection anatomic images obtained from three other cadaveric equine forelimbs for this purpose.

Data Import and Results

• Once the soft tissue and bony structures were recreated in the same coordinate system, the data was then transferred to a software package called SIMM which is designed for interactive musculoskeletal modeling.
• The combination of the CT and MR images data acquisition and the anatomical images contributed to an efficient and accurate generation of a 3D model of an average-sized equine adult horse’s musculoskeletal structures.

Applications and Implications

• The 3D model created in this research can be extensively applied to studying factors contributing to injuries in equine athletes. This also can help in planning and evaluating the impact of orthopedic surgical procedures in horses.
• The research demonstrates the potential of the combined use of CT and MRI scans for advanced imaging and modeling purposes. The process could also be applied to other animals and potentially to human medical research.