Hounsfield unit measurements to predict odontoid fracture union in elderly patients: posthoc subgroup analysis from an international prospective comparative study. - Huybregts JGJ; Jacobs WCH; van Haaster LWF; Ruitenbeek EK; Arts MP; Osti M; Slooff WM; Öner FC; Gulati S; Appelman-Dijkstra NM; Steyerberg EW; Lycklama À Nijeholt GJ; et al. (The spine journal : official journal of the North American Spine Society, 2025)