RESUMO
BACKGROUND: To assess the reliability of the indicators for performing magnetic resonance imaging in patients with scoliosis and assess the incidence of neural axis anomalies in a population with scoliosis referred to a specialist centre. METHODS: A retrospective review of magnetic resonance imaging (MRI) reports of all patients under the age of 18 who underwent a pre-operative MRI for investigation of their scoliosis between 2009 and 2014 at a single institution was performed. RESULTS: There were 851 patients who underwent an MRI scan of their whole spine with a mean age of 14.08 years. There were 211 males and 640 females. One hundred and fourteen neural axis abnormalities (NAA) were identified. The presence of a left sided thoracic curve, a double thoracic curve, being male nor being diagnosed before the age of 10 were found to be statistically significant for the presence of a NAA. Furthermore, 2.34% of patients were also found to have an incidental finding (IF) of an extraspinal abnormality. CONCLUSIONS: From our series, the reported indications for performing an MRI scan in the presence of scoliosis are not reliable for the presence of an underlying NAA. We have demonstrated that there is a number of intra and extra dural anomalies found on MRI without clinical symptoms and signs. This acts as normative information for this group. KEYWORDS: Scoliosis; magnetic resonance imaging (MRI); neural axis abnormalities (NAA); adolescent idiopathic scoliosis (AIS).
RESUMO
STUDY DESIGN: Technical note. OBJECTIVE: We describe a novel technique of bilateral longitudinal sacral osteotomy allowing direct reduction of high pelvic incidence (PI) and correction of sagittal imbalance. METHODS: A 25-year-old female patient presented with a disabling lumbo-sacral kyphosis fused in situ through previous operations with residual low-grade wound infection and grade IV L5/S1 spondylolisthesis with severity index (SI) of 65%. A two-stage correction was performed. First anterior in situ fixation of the L4-L5-S1 segments was performed using a hollow modular anchorages (HMA) screw and L3/L4 anterior interbody cage. The second stage consisted of instrumentation of the lower lumbar spine and pelvis; placement of an S1 transverse K-wire as pivot point and bilateral longitudinal sacral osteotomy which allowed for gradual retroversion of the central sacrum relative to the pelvis. RESULTS: Sacrum was derotated by 30° which allowed to restore spinal sagittal balance and decrease SI by 15%. Postoperative recovery was complicated by a flare up of the pre-existing deep wound infection. CONCLUSIONS: Bilateral longitudinal sacral osteotomy appears to be a safe and efficient way of correcting the sagittal imbalance caused by an extremely high PI. Although technically demanding, it achieves good radiological and functional outcomes and avoids entering the spinal canal.
