[Utilidad de la resonancia magnética dinámica para la evaluación de la inestabilidad disco-vertebral vs. la resonancia magnética estática].

INTRODUCTION: Dynamic magnetic resonance imaging (dMR) is useful to evaluate the unstable cervical spine; it evaluates soft components of the cervical spine and dynamic cervical movements.

OBJECTIVE: To describe and analyze the frequency of presentation of herniated discs with static MRI and compare with dMR.

METHOD: During December 2014 to February 2016, patients with cervicalgia and suspected cervical instability were evaluated. An observational, descriptive, cross-sectional study was performed, where images obtained in flexion and extension were analyzed using a device compatible with MRI.

RESULTS: 29 patients entered the protocol, 7 were excluded. Average age: 50 years. Of the 22 patients, 154 intervertebral discs were evaluated, demonstrating 52 herniated discs, 78% were disc protrusions. Most affected level: C5 (31%). During the dynamic maneuvers it was shown that 30 were unstable, showing modification during the maneuvers of flexion and extension, 22 hernias remained stable. Five patients demonstrated bone instability of vertebral bodies.

CONCLUSIONS: The dMR can be used in our environment since the acquisition cost is low and provides information for the evaluation of spinal disc instability showing findings not visible in sMR. Obtaining a relative risk of 16 and p < 0.05.