Posterior pedicle screw placement and hemivertebra resection by using intraoperative 3D image spinal navigation for the treatment of children congenital kyphoscoliosis

English Keywords:Computer assistance  Osteotomy  Congenital kyphoscoliosis  Pedicle fixation

English Abstract:

  【Abstract】 Objectives: To evaluate the clinical effect of posterior pedicle screw placement and hemivertebra resection guided by spinal navigation with the intraoperative three dimensional(3D) image modality. Methods: Between May 2010 and April 2013, 18 children with congenital kyphoscoliosis underwent posterior pedicle screw fixation and hemivertebra resection by using intraoperative 3D image spinal navigation. All 18 children(7 males and 11 females) aged 7.6±2.9 years were diagnosed as kyphoscoliosis caused by congenital hemivertebra. Pedicle screw insertion and hemivertebra resection were performed guided by intraoperative 3D image spinal navigation. The pedicle screw position and hemivertebra resection were assessed by CT scan and the correction of Cobb angle was assessed by X-ray films preoperatively and postoperatively. Results: The operation time was 216±55 minutes and intraoperative bleeding was 732±378ml. A total of 127 pedicle screws was placed in 18 patients(4-12). 124 screws were accurtately inserted into the pedicles assessed by postoperative CT scanning(97.6% accuracy rate). 1 and 2 screws had a perforation of the medial and lateral pedicle walls. All the hemivertebrae were completely resected. Among these 18 patients, 16 cases were followed up for 18.5±8.0 months. The preoperative mean coronal Cobb angle was 44.5°±11.4°, which compared to (9.3°±4.7°) of postoperation. The mean coronal Cobb angle of final follow-up was 9.7°±5.0° with a (78.2±7.8)% correction. In sagittal plane, the preoperative mean Cobb angle was 32.2°±7.3°, which returned to 7.2°±3.5° postoperatively. The mean sagittal Cobb angle of final follow-up was 7.7°±3.9°. The postoperative correction was (76±9.4)%. The significant difference was found in coronal and sagittal Cobb(P＜0.01). All 16 patients showed bony fusion at final follow-up. The broken of pedicle screw was found in one patient. 1 patient with Hemopneumothorax was treated with closed thoracic drainage. No instrument failure and neurological deficit were observed. Conclusions: Intraoperative 3D image-guided spinal navigation for placement of pedicle screws is of high accuracy and high safety in correcting the spinal deformity.