Objective To assess the cl inical significance of transpedicular screw insertion in lower cervical vertebra assisted by multi-spiral CT (MSCT) three dimentional (3D) image reconstruction techniques. Methods Eight cervical vertebra specimens were examined by MSCT, and the messages were sent to SGI02 Workstation; according to the parameter requirements of lower cervical pedicle fixation, by using post-process of volume rendering (VR) the condition was judged and multi-plannar reformation (MPR) was used to do individual analysis; and the ideal path of screw insertion was obtained andthe related parameters were measured. After preoperative plan being finished, referring to these measured parameters, 3.5 mm screws were inserted into C3-7 pedicles of these 8 specimens. After insertion of screws, MSCT scanning and 3D reconstruction were performed again to evaluate the accuracy of lower cervical pedicle screw inserting. From May 2007 to November 2009, 28 patients who received screw insertion in lower cervical spines were given MSCT scanning and 3D reconstruction to evaluate the illness situation, to confirm shortest fixation volumes, and to collect the parameters of aim pedicle screw insertion. Results The time of insertion for each screw was (392 ± 62) seconds. It was found that one pedicle was clausura (1.25%, 1/80) and five pedicle diameters in coronal view were less than 3 mm (6.25%, 5/80), which all were not fit for screw insertion. A total of 74 screws were placed successfully. One-time success rate of screw insertion was 95.95% (71/74). The total accuracy rate was 91.89% (68/74). Six screws penetrated (8.11%). According to the Richter penetrating classification: grade one was 6.76% (5/74) and grade two was 1.35% (1/74). There were significant differences (P lt; 0.05) in penetrated rate between our study and anatomic landmark local ization (47.37%), Miller methods (25.00%), and there was no significant difference (P gt; 0.05) when compared with Abumi method (6.70%), hopper method (7.10%), pipel ine deoppilation method (5.20%) and navigation technique (11.30%). In cl inical 28 cases, 121 screws were inserted; one pedicle was clausura and one was fissure fracture, which all were unfit for insert screw in preoperative plan, the surgery project was adjusted. After operation, 17 patients (76 screws) were given MSCT scanning again. A total of 67 screws (88.16%) were placed successfully. Nine screws (11.84%) penetrated, grade one was 7.89% (6/76) and grade two was 3.95% (3/76). Conclusion It is accurate to apply MSCT 3D reconstruction techniques to measure the ideal screw canal in preoperative individual ized plan. Strictly following individual quantitative data, the safety and accuracy of the surgery can be improved. And it is feasible and available to use MSCT MPR imaging to evaluate the accuracy of pedicle screw insertion.
Objective To discuss the selection of anterior or posterior or a combination of anterior and posterior surgical treatment of lower cervical dislocation. Methods A retrospectively study was performed on 28 patients with lower cervical dislocation who received operative treatment between January 2005 and October 2008. There were 19 males and 9 femaleswith an average age of 38 years (range, 19-57 years), including 21 cases of fresh dislocation and 7 cases of old dislocation. The time from injury to hospitalization was 3 hours to 58 days. According to Allen classification, all cases had flexion injury, including 19 cases of degree I dislocation, 2 cases of degree II, 5 cases of degree III, and 2 cases of degree IV. At admission according to Frankel classification, 7 cases were rated as grade A, 4 as grade B, 9 as grade C, 3 as grade D, and 5 as grade E. All patients received open reduction, internal fixation, and il iac bone graft spinal fusion. Of them, combined anterior and posterior approach operation were given in 4 cases, single anterior operation in 22 cases, and single posterior operation in 2 cases. Results All operations were completed successfully and the spinal cord injury did not deteriorate after operation. Esophageal fistula occurred in 1 case receiving anterior approach operation and was cured after 1 month. Infection of wound occurred in 1 case and was cured after dressing change. The other incisions healed by first intention. One case (Frankel grade A) died of pulmonary infection 6 weeks after operation. Twenty-seven patients were followed up 21-38 months. Two cases suffered from shoulder pain 12 months after operation. X-ray films showed complete reduction, normal height of vertebral space and normal sequence of cervical spine after operation. All cases obtained bone fusion after 3.5-6.0 months of operation (4.2 months on average). Frankel grades were improved in different degrees after operation. Conclusion The operation plan of lower cervical dislocation should be determined by the neurologic status of the patient, and the classification of the injury as a unilateral or bilateral dislocation. Anterior cervical discectomy, fusion, and fixation were available in the lower cervical dislocation.
OBJECTIVE: To investigate surgical reconstruction of stability of lower cervical spine in children suffering trauma, tuberculosis and tumor. METHODS: From January 1998 to September 2001, 8 cases of unstable lower cervical spine were treated by operations, of anterior decompression, massive iliac bone grafting, posterior fixation with spinous process tension band wiring, and fusion with heterogeneous iliac bone grafting. RESULTS: With an average following up of 1 year and 9 months (6 months to 4 years and 3 months), 3 cases recovered excellently, 4 cases recovered well and 1 case died of pulmonary infection. CONCLUSION: The above results indicate that anterior decompression, massive iliac bone grafting, posterior fixation with spinous process tension band wiring and fusion with heterogeneous iliac bone grafting can be used as one of the methods to reconstruct the stability of lower cervical spine in children.
ObjectiveTo investigate the relationship between O-EA angle and lower cervical curvature in patients with anterior atlantoaxial dislocation undergoing occipitocervical fusion, and to analyze the effect of O-EA angle on lower cervical curvature.MethodsThe clinical data of 61 patients with anterior atlantoaxial dislocation undergoing occipitocervical fusion who were admitted between April 2010 and July 2018 and met the selection criteria were retrospectively analyzed. There were 32 males and 29 females, with an age of 14-76 years (mean, 50.7 years). The fixed segment included 19 cases of C0-C2, 27 cases of C0-C3, 14 cases of C0-C4, and 1 case of C0-C5. The O-EA angle, C2-7 Cobb angle, and T1 tilt angle were measured before operation and at last follow-up. According to the O-EA angle measured at last follow-up, the patients were divided into <95° group (group A), 95°-105° group (group B), and >105° group (group C), and compared the differences of gender, age, fixed segment (short segment was at C3 and above, long segment was beyond C3), and C2-7 Cobb angle. Correlation analysis between the O-EA angle and C2-7 Cobb angle before operation and at last follow-up, as well as the changes of O-EA angle and C2-7 Cobb angle between before operation and at last follow-up were analyzed.ResultsAll 61 patients were followed up 12-24 months, with an average of 22.4 months. There was no significant difference in O-EA angle, C2-7 Cobb angle, and T1 tilt angle before operation and at last follow-up (P>0.05). According to the last follow-up O-EA angle grouping, there were 14 cases in group A, 29 cases in group B, and 18 cases in group C. There was no significant difference in age, gender composition, and fixed segment composition among the three groups (P>0.05); the differences in C2-7 Cobb angles among the three groups were significant (P<0.05), groups A, B, and C showed a gradually increasing trend. The O-EA angle was positively correlated with C2-7 Cobb angle before operation and at last follow-up (r=0.572, P=0.000; r=0.618, P=0.000); O-EA angle change at last follow-up was also positively correlated with C2-7 Cobb change (r=0.446, P=0.000).ConclusionThe O-EA angle of patients with anterior atlantoaxial dislocation is positively correlated with C2-7 Cobb angle. Too large O-EA angle should be avoided during occipitocervical fixation, otherwise it may accelerate the degeneration of the lower cervical spine.
ObjectiveTo introduce and interpret ABCD classification system for subaxial cervical spine injury. MethodsThe literature related to subaxial cervical spine injury classification system was extensively reviewed, analyzed, and summarized so as to introduce the ABCD classification system. ResultsThe ABCD classification system for subaxial cervical spine injury consists of 3 parts. The first part of the proposed classification is an anatomical descri ption of the injury; it del ivers the information whether injury is bony, ligamentous, or a combined one. The second part is the classification of nerve function, spinal stenosis, and spinal instabil ity. The last part is optional and denotes radiological examination which is used to define injury type. Several letters have been used for simplicity to del iver the largest amount of information. And a treatment algorithm based on the proposed classification is suggested. ConclusionThe ABCD classification system is proposed for simplification. However further evaluation of this classification is needed.
ObjectiveTo investigate the effectiveness of treatment of locked lower cervical fracture and dislocation with anterior cervical fusion and internal fixation combined with the release of the interlocking facet through the Luschka joint and anterior lamina space.MethodsTwelve patients with lower cervical interlocking fracture and dislocation were analyzed retrospectively between January 2013 and June 2015. There were 7 males and 5 females, aged 25-59 years with an average age of 38.4 years. The disease duration was 9.6 hours to 100 days with an average of 7.3 days. There were 8 cases of unilateral locking and 4 cases of bilateral locking; 4 cases of old injury and 8 cases of fresh injury. The injured segments were 2 cases of C3, 4, 5 cases of C4, 5, 3 cases of C5, 6, and 2 cases of C6, 7. According to Meyerding classification, there were 9 cases of grade Ⅰ and 3 cases of grade Ⅱ. According to the functional classification of American Spinal Injury Association (ASIA), there were 2 cases of grade C, 6 cases of grade D, and 4 cases of grade E. The interlocking facet was released through the Luschka joint and anterior lamina space, and the anterior cervical fusion and internal fixation were used to treat the fracture and dislocation of the lower cervical spine. The recovery of spinal cord function was judged by the functional classification of ASIA; visual analogue scale (VAS) score, neck disability index (NDI) score, modified Japanese Orthopaedic Association (m-JOA) score were used to evaluate the clinical efficacy; the Cobb angle of fusion segment were observed by X-ray film. The intervertebral bone graft fusion was evaluated at 6 months after operation.ResultsThe average operation time was 78.30 minutes, the average intraoperative blood loss was 167.30 mL, and the average postoperative drainage volume was 58.12 mL. No blood transfusion was given during or after operation. During the operation, there was no accidental injury of large blood vessels, esophagus, and trachea; no laryngo edema, dysphagia, hoarseness, and cerebrospinal fluid leakage occurred after operation; no spinal cord injury or nerve root injury aggravated; the incision healed by first intention, and no infection occurred. All 12 cases were followed up 15-20 months, with an average of 16.5 months. The symptoms and function of the nerve injury were significantly improved when compared with that before operation. Re-examination of the cervical spine X-ray film at 6 months after operation showed that the Cage or bone graft was not displaced or broken, the screw was not loosened or detached, and the intervertebral graft fusion rate was up to 100%. At last follow-up, the ASIA grade, Cobb angle of fusion segment, neck pain VAS score, m-JOA score, and NDI score were significantly improved when compared with preoperative one (P<0.05).ConclusionThe effectiveness of treatment of locked lower cervical fracture and dislocation with anterior cervical fusion and internal fixation combined with the release of the interlocking facet through the Luschka joint and anterior lamina space is clear, which not only can make the injured segment get satisfactory reduction, immediate stability and reconstruction, and full decompression, but also can effectively prevent the secondary injury of spinal cord.
ObjectiveTo investigate the effectiveness of cervical pedicle screw implantation technique under regional method.MethodsThe clinical data of 85 patients who met the selection criteria between April 2010 and May 2018 were retrospectively analyzed. There were 57 males and 28 females, aged 35-68 years, with an average of 57.6 years. Among them, there were 10 cases of ossification of posterior longitudinal ligament, 68 cases of cervical spondylosis with multilevel stenosis, 3 cases of cervical tumor, 1 case of congenital malformation, and 3 cases of cervical trauma; the lower cervical spine lesions involved C3-C7. Preoperative Frankel spinal cord injury grading: 2 cases of grade C, 51 cases of grade D, and 32 cases of grade E. Cervical pedicle screw implantation technique under regional method was performed with a total of 618 pedicle screws. Postoperative changes in neurological symptoms were observed; cervical mouth opening anteroposterior and lateral X-ray films and cervical CT examinations were performed to evaluate the pedicle screws position.ResultsThe operation time was 2.5-4.0 hours, with an average of 3.0 hours. The intraoperative blood loss was 180-550 mL, with an average of 345 mL. No intraoperative vascular or nerve injury occurred. The patients with neurological symptoms were relieved to varying degrees. There were 2 cases of superficial incision infection after operation, the wound healed after enhanced dressing change. The postoperative hospital stay was 5-14 days, with an average of 8.4 days. At discharge, Frankel neurological grading was grade D in 26 patients and grade E in 59 patients. All the patients were followed up 6-24 months, with an average of 13 months. At last follow-up, cervical X-ray films showed the good pedicle screw fixation without loosening. Cervical CT evaluated the position of pedicle screws: 523 pedicle screws (84.7%) in grade Ⅰ, 80 (12.9%) in grade Ⅱ, and 15 (2.4%) in grade Ⅲ; the accuracy rate of the screw position was 97.6%.ConclusionCervical pedicle screw implantation technique under regional method can significantly improve the success rate of screw implantation. It is easy to operate, does not destroy the bone cortex, and has stable fixation.
This study aims to develop and validate a three-dimensional finite element model of inferior cervical spinal segments C4-7 of a healthy volunteer, and to provide a computational platform for investigating the biomechanical mechanism of treating cervical vertebra disease with Traditional Chinese Traumotology Manipulation (TCTM). A series of computed tomography (CT) images of C4-7 segments were processed to establish the finite element model using softwares Mimics 17.0, Geromagic12.0, and Abaqus 6.13. A reference point (RP) was created on the endplate of C4 and coupled with all nodes of C4. All loads (±0.5, ±1, ±1.5 and ±2 Nm) were added to the RP for the six simulations (flexion, extension, lateral bending and axial rotation). Then, the range of motion of each segment was calculated and compared with experimental measurements of in vitro studies. On the other hand, 1 Nm moment was loaded on the model to observe the main stress regions of the model in different status. We successfully established a detail model of inferior cervical spinal segments C4-7 of a healthy volunteer with 591 459 elements and 121 446 nodes which contains the structure of the vertebra, intervertebral discs, ligaments and facet joints. The model showed an accordance result after the comparison with the in vitro studies in the six simulations. Moreover, the main stress region occurred on the model could reflect the main stress distribution of normal human cervical spine. The model is accurate and realistic which is consistent with the biomechanical properties of the cervical spine. The model can be used to explore the biomechanical mechanism of treating cervical vertebra disease with TCTM.