Digital morphological study of thoracic pedicle in children / 局解手术学杂志

Objective To investigate the morphological regularity of the thoracic pedicle screw in 4 to 12 years old children by the digital technology,and to provide the theoreticl basis for thoracic pedicle screw fixation in children.Methods A total of 60 healthy children aged from 4 to 12 years old with computed tomography(CT) data of thoracic spine were divided into three groups by age,each group 20 cases.Then they were examined by MIMICS software and the parameters of pedicle width(PW),pedicle height(PH),the length of screw path(SL),e angle and f angle were measured.Results The pedicle width,pedicle height,the SL of the pedicle generally showed a rising trend with advancing age.There were significant differences in the PW,PH and LS between the three group(P0.05).E angle of the pedicle generally showed a decreasing trend with increasing vertebral order,and e angle of T11 to T12 showed negative angle.The f angle showed a wavy descending trend.Conclusion There was significant difference in correlation parameters of thoracic pedicle with increasing age in healthy children,which indicates that the pedicle screw fixation for the kind of children should be performed based on 'the Principle of individualization' to improve the success rate of surgery.

Scoliosis Correction with Thoracic Pedicle Screws: Posteroanterior C-arm Rotation Method / 대한정형외과학회잡지

Purpose: This study evaluated a practical, safe and accurate method of thoracic pedicle screw insertion for the surgical treatment of scoliosis using the posteroanterior C-arm fluoroscopy rotation method. Materials and Methods: A total of 611 thoracic pedicle screws were inserted in 45 patients using the posteroanterior (PA) C-arm rotation method. CT scans were taken postoperatively in the transverse and sagittal sections to evaluate the pedicle screw placement. Results: A mean preoperative curve of 57.7o was corrected to 17.1o (range, 3o-45o) in the coronal plane. The postoperative CT scans revealed that 10 screws (1.6%) had penetrated the medial cortex by a mean distance of 3.0 mm and 56 screws (9.2%) penetrated the lateral cortex by a mean distance of 3.5 mm. No screw penetrated the inferior or superior cortex in the sagittal plane. However, 21 screws (3.4%) penetrated the anterior cortex. No neurological or vascular complications were encountered, and none of the screws required replacement. Conclusion: Thoracic pedicle screw insertion in scoliosis patients using the posteroanterior C-arm rotation method is a practical, simple and safe technique that allows the en face visualization of both pedicles by rotating the C-arm to compensate for the rotational deformity.

Congenital Absence of Thoracic Spine Pedicle: Case Report / 대한척추외과학회지

Congenital absence of a thoracic pedicle is a rare clinical entity, and this can be misdiagnosed as an acquired absence of the pedicle that is the result of trauma, tumor, or infection. Initial evaluations with conventional radiography frequently lead to misinterpretation and to misguided intervention. Computed tomography can be the most helpful modality to confirm the diagnosis. The congenital absence of pedicles, in contrast to the acquired absence of pedicles, can be managed successfully by conservative treatment or even without treatment. We report a case of an absent thoracic pedicle and we describe the presentation, diagnosis, and treatment together with a review of the literature.

Thoracic Pedicle Screw Insertion in Scoliosis Using Posteroanterior C-arm rotation Method / 대한척추외과학회지

STUDY DESIGN: A prospective study of the accuracy of thoracic pedicle screws inserted in scoliotic patients. OBJECTIVES: To evaluate and present a practical, safe and accurate method for thoracic pedicle screw insertion in the surgical treatment of scoliosis using the posteroanterior c-arm fluoroscopy rotating method. SUMMARY OF LITERATURE REVIEW: Previous studies have emphasized the clinical importance, yet difficulty, of accurate thoracic pedicle screw insertion in scoliotic patients. Three-dimensional alterations in the pedicle orientation of scoliotic patients makes the accurate insertion challenging. No reports exist on the accuracy and benefits of posteroanterior c-arm fluoroscopy, which is rotated to allow visualization from en face, in real patients. MATERIALS AND METHODS: A total of 350 thoracic pedicle screws were inserted in 29 patients, including 24 with idiopathic scoliosis, using the posteroanterior (PA) c-arm rotation method. The smallest patient weighed 14 kg, and the next smallest 17 kg. The average preoperative curve was 60.9 degrees(range, 45 degrees~101 degrees). CT scans were taken, postoperatively, in the transverse and sagittal sections to evaluate the pedicle screw placement. RESULTS: The mean preoperative curve of 60.9 degrees was corrected to 15.4 degrees(range, 3 degrees~45 degrees) in the coronal plane, a correction of 74.7%. A mean of 12.1 thoracic screws were inserted per patient. On analysis of the postoperative CT scans, 39(11.1%) of the 350 screws penetrated the medial or lateral pedicle cortices, 8(2.3%) into the medial cortex and 31(8.9%) into the lateral cortex, by mean distances of 3.3 and 3.6 mm, respectively. No screws penetrated the inferior or superior cortices in the sagittal plane, but 16(4.6%) penetrated the anterior cortex. No neurological or vascular complications were encountered, and none of the screws required subsequent replacement. CONCLUSIONS: Thoracic pedicle screw insertion in scoliotic patients, using a posteroanterior c-arm rotation method, allows the en face visualization of both pedicles by rotating the c-arm to compensate for rotational deformity, which makes it a practical, simple and safe method.