Dynamic cervical myelopathy in young adults.

Purpose: Non-traumatic cervical chronic joint instability in young adults is a rare and underexplored entity. We assessed the diagnostic relevance of dynamic MRI, and the clinical and radiological outcome after anterior cervical interbody fusion (ACIF) in these cases.
Methods: Six young patients (mean age 34 years) with cervical myelopathy without compression on static imaging had a dynamic MRI. Joint instability was defined by a reduction of the canal diameter on dynamic sequences. Clinical and radiological outcomes were assessed after surgery by examination, cervical X-rays, static and dynamic MRI.
Results: All the patients had joint instability. Four patients underwent surgery. Clinical status improved 1 year after surgery. All patients had a satisfactory fusion at 6-month follow-up and no residual compression at 1 year.
Conclusion: Dynamic MRI can help detect a joint instability in young patients with cervical myelopathy without compression. ACIF seems to be efficient in these cases.