MANDIBULAR CONDYLAR FRACTURES AND ACUTE ATLANTO-AXIAL SUBLUXATION PART 2 A PHYSIOPATHOLOGICAL FACTOR FOR THE CERVICAL SPINE SPRAIN

Aim and Study Design. The AA debate the physiopathology of the acute cervical injure in the event of mandibular condylar fractures. To achieve this specific purpose they have used the same sample of patients than in the Part 1. 25 non consecutive cases of condylar mandibular fractures (16 Males and 9 Females, Age -mean-range: 22.96 years /14-36) observed and treated in the Maxillofacial Surgery Department of the University of L’Aquila have been studied. Type of fracture - Unilateral: 19 cases (solitary: 12; associated with other mandibular fractures: 7, homolateral : 2). Bilateral: 6 cases (equivalent: 2, not equivalent: 4). A control group has been constituted by 10 patients, 5 males and 5 females, aged from 19 to 24 years (mean-range: 21.6) suffering from acute isolated cervical distorsion (whiplash). The study has been executed by the analysis of x-ray and CT-CT/3D of the mandibular condylar regions, the occipital-atlanto-axial structures and the cervical region. Results. The AA point out that in all the patients the following constant alterations that link up with these fractures have been observed: the rotation of atlas, the atlanto-axial subluxation and the derangement of the occipital-atlanto-epistropheal joint, homolateral to the side of the mandibular condylar fracture. The cervical spine shows the constant loss of physiological lordosis with hinge between C3 and C4. In the whiplash, as the AA have been able to assess in the control group, there aren’t alterations of occipital-atlanto-axial joint and the kinetic vector is placed on the longitudinal plane. In the mandibular condylar fractures the kinetic mechanism is completely different regarding the whiplash. The point of entry is the chin and the kinetic vector is oriented down-up, sometimes oblique in the opposite side. Subsequently the kinetic force is transmitted throughout the mandibular structure and causes the condylar or bicondylar fracture. The kinetic vector is placed before on the vertical plane, then on the horizontal plane and later on the vertical plane. Therefore the dynamics of the crash cannot cause the swaying of the head as in the whiplash. Indeed in the mandibular condylar fractures the AA have observed the cervical distorsion with the loss of lordosis on the sagittal plane without whiplash and also they observed a constant derangement of the cranio-cervical joint and the atlanto-axial subluxation. Conclusions. These results allow to delineate a different physiopathological mechanism: in the event of mandibular condylar fractures, the sprain of the cervical spine seems to be caused by the acute atlanto-axial subluxation.