doi:10.1038/s41598-023-30512-3engHidalgo García, CésarLorente, Ana I.López-de-Celis, CarlosLucha López, María OrosiaRodríguez-Sanz, JacoboMaza-Frechín, MarioTricás-Moreno, José MiguelKrauss, JohnPérez-Bellmunt, AlbertEffects of occipital-atlas stabilization on the upper cervical spine rotation combinations: an in vitro studyART-2023-132783The purpose of this study is to compare axial rotation range of motion for the upper cervical spine during three movements: axial rotation, rotation + flexion + ipsilateral lateral bending and rotation + extension + contralateral lateral bending before and after occiput-atlas (C0–C1)stabilization. Ten cryopreserved C0–C2 specimens (mean age 74 years, range 63–85 years) were manually mobilized in 1. axial rotation, 2. rotation + flexion + ipsilateral lateral bending and 3. rotation + extension + contralateral lateral bending without and with a screw stabilization of C0–C1. Upper cervical range of motion and the force used to generate the motion were measured using an optical motion system and a load cell respectively. The range of motion (ROM) without C0–C1 stabilization was 9.8° ± 3.9° in right rotation + flexion + ipsilateral lateral bending and 15.5° ± 5.9° in left rotation + flexion + ipsilateral lateral bending. With stabilization, the ROM was 6.7° ± 4.3° and 13.6° ± 5.3°, respectively. The ROM without C0–C1 stabilization was 35.1° ± 6.0° in right rotation + extension + contralateral lateral bending and 29.0° ± 6.5° in left rotation + extension + contralateral lateral bending. With stabilization, the ROM was 25.7° ± 6.4°(p = 0.007) and 25.3° ± 7.1°, respectively. Neither rotation + flexion + ipsilateral lateral bending (left or right) or left rotation + extension + contralateral lateral bending reached statistical significance. ROM without C0–C1 stabilization was 33.9° ± 6.7° in right rotation and 28.0° ± 6.9° in left rotation. With stabilization, the ROM was 28.5° ± 7.0° (p = 0.005) and 23.7° ± 8.5° (p = 0.013) respectively. The stabilization of C0–C1 reduced the upper cervical axial rotation in right rotation + extension + contralateral lateral bending and right and left axial rotations; however,this reduction was not present in left rotation + extension + contralateral lateral bending or both combinations of rotation + flexion + ipsilateral lateral bending.2023http://zaguan.unizar.es/record/12439910.1038/s41598-023-30512-3http://zaguan.unizar.es/record/124399oai:zaguan.unizar.es:124399Scientific reports (Nature Publishing Group) 13 (2023), 3578 [10 pp.]byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess