LAUSR

Rationale: Chiari type I malformation (CM1) and occult tethered cord syndrome (OTCS) are considered to be malformations associated with subtle structural abnormalities of the terminal filum. Few studies have reported patients with CM1 and OTCS. Treatment strategy for patients of CM1 associated with OTCS is controversial. Patient concerns: A 14-year-old child was admitted with intermittent pain and numbness in the right upper limb. And he had urinary frequency, neck pain, back pain, and numbness simultaneously. The imaging examinations showed CM1, syringomyelia, small fat in the filum at the level of the L2 vertebral body but the conus medullaris at the aspect of the L1 vertebral body. Diagnoses: The child was diagnosed with CM1 associated with OTCS. Interventions: Patient underwent sectioning of filum terminale (SFT) under electrophysiological monitoring during the first hospital and posterior fossa decompression (PFD) during the second hospital. Outcomes: After first discharge pain of the right upper limb was relieved, but he still felt numbness. And his numbness was relieved after second discharge. The imaging examinations also showed corresponding improvement during the 2-year follow-up period. Lessons: For pediatric patients with CM1 and TCS, treatment trouble is not only to choose the staging operation or simultaneous operation but also staging procedures for treatment of 2 lesions. Detailed preoperative evaluation is essential for development of individualized surgical plan. Staging operation of firstly minimally invasive SFT and later PFD may be helpful for such cases owing to its positive effect on both the symptoms and imaging findings.