Pain improvement in patients with syringomyelia and Chiari I malformation treated with suboccipital decompression and tonsillar coagulation.

Pain experienced by patients who have syringomyelia associated with Chiari I malformation (SACM) includes headache, cervicalgia and radiculalgia. We studied the correlation of clinical and imaging factors with the evolution of pain and surgical outcome at 12 months. We performed a prospective study of 13 patients who presented with SACM and who underwent suboccipital decompression, C1 laminectomy, tonsillar coagulation and duraplasty. The Bidzinski Outcome Scale was used. Post-operatively, pain improvement was observed in 11 patients and the syrinx resolved in 6 patients and reduced in 7. Eleven patients had a good or very good outcome, while 2 patients had a poor outcome. A post-operative medullary axial occupation of the syrinx less than 75% of the spinal canal was associated with improved post-operative pain. Longer duration of symptomatology was associated with a poor outcome and failed pain control. The size and form of the syrinx, as well as early surgical treatment, are the factors that most influence the control of pain post-surgery in patients with SACM.