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Updated: Apr 19, 2026

Construction of a Realistic, Whole-Body, Three-Dimensional Equine Skeletal Model using Computed Tomography Data
Published on: February 25, 2021
Three-dimensional anatomy of the ostrich (Struthio camelus) knee joint
Kyle P Chadwick1, Sophie Regnault1, Vivian Allen1
1Structure & Motion Lab, Department of Comparative Biomedical Sciences, The Royal Veterinary College , Hatfield , United Kingdom.
Abstract:
The three-dimensional anatomy of the ostrich (Struthio camelus) knee (femorotibial, femorofibular, and femoropatellar) joint has scarcely been studied, and could elucidate certain mechanobiological properties of sesamoid bones. The adult ostrich is unique in that it has double patellae, while another similar ratite bird, the emu, has none. Understanding why these patellae form and what purpose they may serve is dually important for future studies on ratites as well as for understanding the mechanobiological characteristics of sesamoid bone development. For this purpose, we present a three-dimensional anatomical study of the ostrich knee joint, detailing osteology, ligaments and menisci, and myology. We have identified seven muscles which connect to the two patellae and compare our findings to past descriptions. These descriptions can be used to further study the biomechanical loading and implications of the double patella in the ostrich.
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