Introduction: Chronic low back pain (LBP) has varying etiologies and can be a challenge to manage. A syringomyelia is a CSF-filled cavitation of the spinal cord that presents with multiple progressive findings including decreased temperature sensation, paresis, paralysis, and pain in the shoulders, back, or extremities. A hydromyelia is a milder dilatation of the central canal and is caused by congenital abnormalities or acquired lesions such as spinal cord trauma or tumors that interfere with CSF fluid dynamics in the spinal cord. Hydromyelia typically present with diffuse pain rather than dissociated sensory loss, and motor deficits are rare. We present a case of chronic LBP secondary to a thoracolumbar hydromyelia successfully treated with a 2-level ACDF.

Methods: Case report and literature review.

Results: A 37-year-old male presented to the University of Arizona Medical Center with acute exacerbation of chronic LBP. The LBP was a dull ache that radiated up his spine. He had normal strength in his legs, and denied sensory deficits and incontinence. His LBP initially began 2 years ago after acute physical exertion. The patient had been previously evaluated on multiple occasions with CT scans of his lumbar spine with reported mild disc bulges. He was evaluated with an MRI of his spine revealing prominent C4-5 and C5-6 osteophyte disc complexes with associated myelomalacia and a hydromyelia extending from T5 to the conus (Figure). He underwent an uncomplicated C4-6 ACDF with complete resolution of his chronic LBP after surgery.

Conclusions: Isolated chronic LBP secondary to a hydromyelia is not well described. Hydromyelia should be considered as a potential cause of idiopathic LBP since resolution of the hydromyelia, through restoration of normal CSF dynamics, may cure the chronic LBP.

Patient Care: This report will raise awareness of a rare, potentially treatable cause of chronic LBP.

Learning Objectives: To review the presentation of hydromyelia as a potential cause of chronic LBP.

References: 1. Canas N, Calado S, Ribeiro C, Vale J. Reversible cervical hydromyelia in subacute combined degeneration. Neurology. Aug 9 2005;65(3):E7. 2. Kyoshima K, Bogdanov EI. Spontaneous resolution of syringomyelia: report of two cases and review of the literature. Neurosurgery. Sep 2003;53(3):762-768. 3. Roser F, Ebner FH, Sixt C, Hagen JM, Tatagiba MS. Defining the line between hydromyelia and syringomyelia. A differentiation is possible based on electrophysiological and magnetic resonance imaging studies. Acta Neurochir (Wien). Feb 2010;152(2):213-219. 4. Wehner T, Ross JS, Ransohoff RM. Fluid in the flute: Reversible hydromyelia. J Neurol Sci. Sep 15 2005;236(1-2):85-86.