Introduction: Attempts to identify factors that influence the spinal deformity in diseases of the neural axis have had varying results. Debate still exists on how effective neurosurgery is in stabilizing or reversing the scoliosis. The purpose of this study was to determine which factors affect scoliosis progression in patients with diseases of the neural axis following neurosurgical management.
Methods: A review of the medical records of Chiari I malformation (CM I), Chiari II malformation (CM II), syringomyelia (SM), and tethered cord (TC) patients was performed at a single institution. Twenty-nine patients treated between 2005-2015 were identified,15 met inclusion and had a minimum 2-year follow-up. Patients who required spinal fusion or reached surgical range (50°) were compared to those that did not, for pre-and post-neurosurgical scoliosis radiographs,presenting neurological symptoms,demographics, skeletal maturity,location of major curve,presence of atypical curves and treatment course.
Results: Fifteen patients (8 females, 7 males) with scoliosis underwent neurosurgical intervention. Ten had TC, 6 CM II, 4 CM I, and 11 had SM. Average age at time of neurosurgery was 7±4 years. Following neurosurgery no patients experienced improvement in their curves (>10° decrease in Cobb angle), 8 patients experienced stabilization (within 10°), and 7 experienced worsening (>10° increase). The spinal deformity surgical group (8 patients) possessed larger curves prior to neurosurgery (mean 42°, range 20 - 63°) compared to the non-surgical group (19°, range 15-26°;p=0.004). CM II patients had the greatest magnitude of curve progression, mean of 49°, compared to patients with CM I (6°) or TC without CM I or II (11°, p=0.01).
Conclusions: Neurosurgical intervention may prevent curve progression in patients with scoliosis and Cobb angles < 30° without complex CM II. Patients with CM II are at a higher risk of curve progression and undergoing spinal fusion compared to patients with CM I, TC, or SM.
Patient Care: In patients with a preoperative Cobb angle < 30° and without CM II we recommend neurosurgical intervention followed by a period of monitoring of the scoliosis for progression. For patients with CM II we recommend close radiographic monitoring for curve progression, early neurosurgical intervention and awareness of the high rate of scoliosis progression and eventual need for spinal fusion.
Learning Objectives: 1.There is an association between Chiari Malformation I, II, tethered cord syndrome, syringomyelia and scoliosis
2.Neurosurgical intervention may prevent curve progression irrespective of the neurological condition in children and adolescents with preoperative Cobb angles < 30° if there is not an associated Chiari II malformation
3.Patients with Chiari II malformation are at higher risk of curve progression and undergoing fusion compared to patients with Chiari I malformation, tethered cord syndrome, or syringomyelia