Evaluation of intraoperative coronal alignment using a computer-assisted rod bending system (CARBS) without intraoperative radiation exposure in adult spinal deformity surgery: a technical note and preliminary results.

PURPOSE: Intraoperative radiographs and fluoroscopy are used in adult spinal deformity (ASD) surgery to prevent postoperative coronal malalignment but with limited accuracy. Therefore, we applied a computer-assisted rod bending system (CARBS: Bendini®) for an intraoperative coronal alignment evaluation. The purpose of this study is to introduce this novel technique and validate its accuracy. METHODS: Fifteen ASD patients were included in the study. The heads of the bilateral S1 pedicle screws (S1), the S1 spinous process, and the bilateral greater trochanter (GT) and the C7 spinous process were recorded with CARBS for an intraoperative coronal alignment evaluation. The lines which connect the bilateral S1 and GT were used as references. The C7-center sacral vertical line (C7-CSVL) on the CARBS monitor was checked, and the C7-CSVL from the intraoperative CARBS recording and postoperative standing whole spine radiograph were compared. RESULTS: Intraoperative C7-CSVL with CARBS was 35.1 ± 31.6 mm when the S1 pedicle screws were used as the reference line and was 16.6 ± 17.8 mm when the GTs were used. Postoperative C7-CSVL by radiograph was 15.1 ± 16.5 mm. In addition, the intraoperative C7-CSVL with CARBS and the postoperative C7-CSVL showed a strong positive correlation in both GT (R = 0.86, p < 0.01) and in S1(R = 0.79, p < 0.01), with a better correlation found in GT than in S1. CONCLUSION: Intraoperative C7-CSVL with CARBS was found to be highly accurate in ASD surgery. Our results suggest that this novel technique can be useful as an alternative to intraoperative radiography and fluoroscopy and may reduce radiation exposure.

Torticollis of a specific C1 dislocation with split atlas.

STUDY DESIGN: A case report. OBJECTIVE: We report a novel case of torticollis disorder because of a congenital split atlas after minor trauma. SUMMARY OF BACKGROUND DATA: Torticollis experienced after minor trauma in childhood is usually because of atlantoaxial rotatory fixation, which is a common disorder in pediatric patients and is usually diagnosed with computed tomography (CT). CT scanning with 3-dimensional reconstruction, however, showed a unique rotation of split atlas, a congenital anomaly that presented with torticollis. METHODS: A female child aged 3 years and 11 months presented to the orthopedic clinic with torticollis after a fall. CT imaging showed no rotatory dislocation of C1-C2. On the 3-dimensional CT reconstruction images, however, anterior and posterior defects in the atlas, the so-called split atlas, and an atypical rotation with malalignment of the posterior arch and asymmetry of the atlantoaxial facet joint were noted. The child was treated with closed reduction using skull traction under general anesthesia. RESULT: Repositioning of the atlas rotation was confirmed using intraoperative 3-dimensional scanning, and open reduction therapy was avoided. The patient was treated with halo vest for 8 weeks and had full recovery of neck motion with resolution of the torticollis. CONCLUSION: We present a novel torticollis disorder caused by C1 rotation of a split atlas with closed reduction treatment.