Showcase Preparation for surgery in veterinary medicine With the help of a 3D printed model from CT scans surgical intervention on a young horse with deformed hind legs was prepared. Thanks to optimal preparation the intervention was successful and the horse is now able to walk without problems. In spring 2017 a young horse which suffered from deformed hind legs was treated at the Animal Hospital Zurich. In order to prepare surgery the legs of the horse were scanned by a CAT scanner. From those scans 3D models were created. The challenge was to get smooth surfaces without artificial holes as the bone density of young horses differs from that of adult animals. Additionally the raw export of the CAT data contained a high number of noisy artefacts. In cooperation with the customer correct 3D models could finally be created. Those 3D models were then printed on a dual extrusion desktop 3D printer (Ultimaker 3) using PLA material together with the water-soluble support material PVA. The selected layer height of 0.15mm represented a trade-off between printing time and resolution. The necessary wedge-shaped cut was performed first on the 3D printed models and surgery thereby prepared. Surgery was subsequently performed. The horse now has a completely normal leg situation and can walk without issues.