Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection，4 cases of old odontoid fracture，2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture； 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
Objective To evaluate the accuracy of pedicle guide device for the placement of the pedicle screws. Methods Pedicle guide device was designed and made for the anatomical trait of pedicle. The 3-Danatomical data of the thoracic pedicles were measured by multislice spiral CT in two embalmed human cadaveric thoracic pedicles spine(T1 -T10). Depending on transverse section angle(TSA) and sagittal section angle(SSA) of pedicle axis, the degree of horizontal dial and sagittal dial were adjusted in the guide device. The screws wereinserted bilaterally in the thoracic pedicles by using the device. After pulling the screws out, the pathways were filled with contrast media. The TSA and SSA of developed pathways were measured. Results Analysis of the difference between pedicle axis and developed pathway was of no statistical significance(P＞0.05). Conclusion The guide device could be easilyoperated and guarantee high accuracy of the pathways of screws and the incidence of pedicle penetration could be significantly reduced.
ObjectiveTo investigate the short-term effectiveness of balloon vertebroplasty combined with short-segment pedicle screw instrumentation for the treatment of thoracolumbar burst fractures. MethodsBetween June 2011 and December 2013, 22 patients with thoracolumbar burst fractures were included. There were 14 males and 8 females, aged 20-60 years (mean, 42.5 years). The fracture segments included T11 in 1 case, T12 in 4 cases, L1 in 10 cases, L2 in 6 cases, and L3 in 1 case. According to AO classification system, there were 13 cases of type A and 9 cases of type B. Spinal cord injury was classified as grade C in 2 cases, grade D in 3 cases, and grade E in 17 cases according to Frankel scale. The time from injury to operation was 3-10 days (mean, 5.5 days). All patients underwent posterior reduction and fixation via the injured vertebra, transpedicular balloon reduction of the endplate and calcium sulfate cement (CSC) injection. The ratio of anterior vertebral height, the ratio of central vertebral height, the sagittal Cobb angle, the restoration of nervous function, and internal fixation failure were analyzed. ResultsPrimary healing of incision was obtained in the others except 2 cases of poor healing, which was cured after dressing change or debridement. All the patients were followed up 9-40 months (mean, 15 months). CSC leakage occurred in 2 cases. Absorption of CSC was observed at 8 weeks after operation with complete absorption time of 12-16 weeks (mean, 13.2 weeks). The mean fracture healing time was 18.5 weeks (range, 16-20 weeks). The ratio of anterior vertebral height, ratio of central vertebral height, and sagittal Cobb angle were significantly improved at 1 week and 3 months after operation and last follow-up when compared with preoperative values (P<0.01), but no significant difference was found among 3 time points after operation (P>0.01). There was no internal fixation failure or Cobb angle loss more than 10°. Frankel scale was improved with no deterioration of neurologic function injury. ConclusionBalloon vertebroplasty combined with short-segment pedicle screw instrumentation is simple and safe for the treatment of thoracolumbar burst fractures, and it can improve the quality of reduction, restore vertebral mechanical performance effectively, and prevent the loss of correction and internal fixation failure.
ObjectiveTo investigate the effectiveness of pedicle screw internal fixation for the atlantoaxial instability of children. MethodsBetween July 2005 and January 2012, 19 cases of atlantoaxial instability were treated, included 10 boys and 9 girls with an average age of 7.5 years (range, 4-15 years). The X-ray films, CT, and MRI examinations of the cervical spine showed craniocervical malformation in 9 cases, congenital os odontoideum in 3 cases, odontoid fracture (type Ⅱ) in 1 case, disruption of transverse ligament in 2 cases, atlantoaxial fracture and dislocation in 4 cases; and spinal cord injury in 8 cases, according to the American Spinal Cord Injury Association (ASIA) impairment scale, 1 case was rated as grade B, 2 as grade C, and 5 as grade D. Preoperative skull traction was performed routinely on all cases, and complete reduction was achieved in 17 cases, no reduction in 2 cases. In 17 patients who achieved complete reduction, pedicle screw internal fixation was used through posterior approach, including occipitocervical fusion and fixation in 5 cases, and atlantoaxial fusion and fixation in 12 cases; in 2 patients with no reduction, pedicle screw internal fixation was used through posterior approach (atlantoaxial fusion and fixation) after release by transoral approach. ResultsThe operation was successfully performed in all patients. The mean operation time was 89 minutes; the mean intraoperative blood loss was 95 mL; the mean postoperative drainage volume was 73 mL; and the mean hospitalization days were 14 days. The patients were followed up 6-27 months (mean, 18.3 months). Satisfactory atlantoaxial fusion was obtained, and bone fusion was obtained at 3-7 months after operation (mean, 4.5 months). No breakage of screw or rods and re-dislocation occurred during follow-up. At last follow-up, the cervical range of motion (CROM) of the left and right rotation were (62.0±5.9)°and (63.9±3.8)°respectively in 5 patients receiving occipitocervical fusion and fixation, showing significant difference when compared with the values of normal children[(72.3±7.0)°and (74.1±7.6)°, respectively] at the same age (t=-3.915, P=0.018; t=-5.954, P=0.004). The CROM of the left and right rotation were (70.5±5.8)°and (72.7±4.9)°respectively in 14 patients receiving atlantoaxial fusion and fixation, showing no significant difference when compared with normal children at the same age (t=-1.417, P=0.180; t=-1.021, P=0.323). The visual analogue scale (VAS) score was significantly decreased from 7.8±1.1 at pre-operation to 3.5±0.8 at last follow-up (t=17.267, P=0.000). In 8 cases having spinal cord injury, 2 cases were rated as grade C, 1 case as grade D, and 5 cases as grade E according to ASIA impairment scale. ConclusionTechnique of pedicle screw internal fixation has been proven to be an effective treatment for the atlantoaxial instability of children. It plays an important part in relieving pain and limitation of the cervical region.
Objective To develop a high-accuracy, better-safety and low-cost cervical pedicle locator system for guiding cervical pedicle screw placement. Methods Cervical pedicle screw locator system was made of stainless steel. Ten cervical specimens from voluntary donation were divided into two groups according to compatibil ity design: control group inwhich 60 screws were planted into C2-7 by free hand; and experimental group in which 60 screws were planted into C2-7 under the guidance of three-dimensional locator system. The condition of screw insertion was observed and the accuracy was evaluated by the integrity of pedicle walls. Results In the control group, 32 screws (53.33%) were placed inside the pedicles and 28 (46.67%) were outside; 9 screws (15.00%) led to nerve root injury, 5 screws (8.33%) caused vertebral artery injury and no spinal cord injury occurred; and the qual ification ratio of screw insertion was 76.67% (excellent 32, fair 14, poor 14). While in the experimental group, 54 screws (90.00%) were placed inside the pedicles and 6 (10.00%) were outside; 1 screw (1.67%) caused vertebral artery injury and no nerve root injury and spinal cord injury occurred; and the qual ification ratio of screw insertion was 98.33% (excellent 54, fair 5, poor 1). There was significant difference between the two groups (P lt; 0.05). Conclusion Cervical pedicle screw locator system has the advantages of easy manipulation, high accuracy of screw placement and low cost. With further study, it can be appl ied to the cl inical.
ObjectiveTo explore the effectiveness percutaneous monoaxial screw combined with polyaxial pedical screw for treating thoracolumbar fracture by comparing with simple polyaxial pedicle screw fixation. MethodsBetween January 2012 and June 2014, 56 cases of thoracolumbar fractures were treated by percutaneous pedicle screw fixation, the clinical data were retrospectively analyzed. Of 56 cases, 30 were treated with percutaneous monoaxial screw combined with percutaneous polyaxial pedical screw fixation (group A), 26 patients with only percutaneous polyaxial pedicle screw fixation (group B). There was no significant difference in gender, age, body mass index, injury causes, time from injury to admission, involved segments, fracture type, and preoperative American Spinal Injury Association (ASIA) stage, visual analogue scale (VAS), the anterior height of the injured vertebrae, Cobb angle, and sagittal index between 2 groups (P>0.05). The operation time, intraoperative blood loss, and complications were recorded and compared between the 2 groups. The VAS score was used to evaluate the improvement of the pain. The sagittal kyphosis Cobb angle, the anterior height of the injured vertebrae, sagittal index, and the average correction (difference between 3 days after oeration and preoperation) and loss degrees (difference between last follow-up and 3 days after operation) were measured on the X-ray films at preoperation, 3 days after operation, and last follow-up. ResultsIncision healing at stage I was obtained, no related complications occurred. The operation time and intraoperative blood loss showed no significant difference between 2 groups (P>0.05). The patients were followed up 20-42 months (mean, 32 months) in group A and 21-44 months (mean, 30 months) in group B. VAS score of group A was significantly lower than that of group B at 3 days after operation (t=-2.277, P=0.027), but no significant difference was found at last follow-up (t=-0.289, P=0.774). X-ray examination showed good position of internal fixation, with no broken nails or exit of nail. There were significant differences in the anterior height of the injured vertebrae, Cobb angle, and sagittal index between at preoperation and at 3 days and last follow-up, and between at 3 days and last follow-up in 2 groups (P<0.05). The anterior height of the injured vertebrae, Cobb angle, and sagittal index of group A were significantly better than those of group B at 3 days and last follow-up (P<0.05), and correction degree were significantly higher than those of group B (P<0.05), but loss degree was not significant between 2 groups (P>0.05). ConclusionPercutaneous monoaxial screw combined with polyaxial pedicle screw fixation is better than simply polyaxial pedicle screw in effects of treating thoracolumbar fracture under the premise of strictly holding indications.
Objective To compare the curative effect of posterior lumbar interbody fusion with autologous il iac crest to that of interbody fusion cage for adult instabil ity of lower lumbar. Methods From February 2003 to October 2006,60 inpatients with lower lumbar instabil ity were treated. Patients were randomized into 2 groups: bone-graft group (n=28) was treated with posterior lumbar interbody fusion with two autologous il iac crests, while cage group (n=32) was treated with posterior lumbar interbody fusion with two quadrate cages. In the bone-graft group, 17 males and 11 females aged (52.78 ± 10.50) years with 3-16 months of disease course, there were 12 cases of degenerative instabil ity, 14 isthmus sl it ol isthe and 2 iatrogenic instabil ity, including 1 case of L3,4, 17 cases of L4,5 and 10 cases of L5, S1. Relative disc space height was (23.24 ± 6.62) mm, disc space activity was (10.50 ± 5.07)º, sagittal saw sl ippage distance was (4.50 ± 1.15) mm and the JOA score was 18.56 ± 2.68. In the cage group, 19 males and 13 females aged (51.75 ± 10.44) years with 3.5-14.0 months of disease course, there were 16 cases of degenerative instabil ity, 14 isthmus sl it ol isthe and 2 iatrogenic instabil ity, including 16 cases of L4,5 and 16 cases of L5, S1. Relative disc space height was (24.34 ± 7.22) mm, disc space activity was (11.12 ± 5.67)º, sagittal saw sl ippage distance was (4.38 ± 0.75) mm and the JOA score was 19.00 ± 4.12. There was no significant difference between the two groups in termsof age, gender, JOA score, disc space activity and relative disc space height preoperatively (P gt; 0.05). Results All patients received the follow-up at the 1st, 3rd, 6th and 12th month postoperatively. There was no significant difference in operation time and hemorrhage amount between the two groups (P gt; 0.05), but significant difference in the cost of operation (P lt; 0.01). Two cases in the bone-graft group suffered donor site pain and received no treatment. Three cases in the bone-graft group and 2 cases in the cage group had symptom of nerve injury 1-2 days after surgery, which were cured after expectant treatment. There were no pseudoarticulation formation, intervertebral space infection and cage aversion in both groups. Significant difference of relative disc space height was found in each group pre- and post- operatively (P lt; 0.01) and significant differences were evident between the two groups at any of the time points (P lt; 0.01). One month after operation, there was significant difference between the two groups (P lt; 0.05). There was also significant difference at the 3rd, 6th and 12th month after operation (P lt; 0.01). No sign offusion was found in each group at the 1st and 3rd month after operation. In bone-graft group, there were 7 vertebral fusion cases 6 months after operation and 23 vertebral fusion cases 12 months after operation. In cage group, there were 8 vertebral fusion cases 6 months after operation and 29 vertebral fusion cases 12 months after operation. There was no significant difference in the rate of fusion at 6 and 12 months follow-up between the two groups (P gt; 0.05). Significant difference of JOA scores was found in each group pre- and post- operatively (P lt; 0.05). And no significant difference in JOA scores at 1, 3, 6, and 12 months follow-up was evident between the two groups (P gt; 0.05). Conclusion There is no significant difference between the two groups in the fusion time, the fusion rate and the cl inical symptoms alleviation, indicating autologous il iac crest is appl icable to interbody fusion for the treatment of adult instabil ity of lower lumbar and good therapeutic effect can be achieved with no immunoreaction and lower cost.
Objective To explore and evaluate the accuracy and feasibil ity of individual rapid prototype (RP) drill templates for atlantoaxial pedicle screw implantation. Methods Volumetric CT scanning was performed in 8 adult cadaveric atlas and axis to collect Dicom format datas. Then three-dimensional (3D) images of atlas and axis were reconstructed and the parameters of pedicles of 3D model were measured by using software Mimics 10.01. The 3D model was saved by STLformat in Mimics. The scattered point cloud data of 3D model were processed and the 3D coordinate system was located in software Imageware 12.1. The curves and surfaces of 3D model were processed in software Geomagic Studio 10. The optimal trajectory of pedicle screw was designed and a template was constructed which accorded with the anatomical morphology of posterior arch of atlas and lamina of axis by using software Pro/Engineer 4.0. The optimal trajectory of pedicle screw and the template were integrated into a drill template finally. The drill template and physical models of atlas and axis were manufactured by RP (3D print technology). The accuracy of pilot holes of drill templates was assessed by visually inspecting and CT scanning. Results The individual drill template was used conveniently and each template could closely fit the anatomical morphology of posterior arch of atlas and lamina of axis. Template loosening and shifting were not found in the process of screw implantation. Thirty-two pedicle screws were inserted. Imaging and visual inspection revealed that the majority of trajectories did not penetrate the pedicle cortex, only 1 cortical penetration was judged as noncritical and did not injury the adjacent spinal cord, nerve roots, and vertebral arteries. The accuracy of atlas pedicle screw was grade 0 in 15 screws and grade I in 1 screw, and the accuracy of axis pedicle screw was grade 0 in 16 screws. Conclusion The potential of individual drill templates to aid implantation of atlantoaxial pedicle screw is promising because of its high accuracy.
To compare the effectiveness of the operations in treatment of thoracolumber spine fracture and dislocation with spinal cord injury in different periods. Methods Between June 2003 and June 2008, 80 cases of thoracolumber spine fracture and dislocation with spinal cord injury were treated. There were 52 males and 28 females with an average age of 37.6 years (range, 28-49 years). According to different operative time, they were divided into 2 groups by randomized controlled study: group A (n=39, operation was performed within 24 hours) and group B (n=41, operation was performed at 3-7 days). In group A, there were 23 cases of degree I-II (group A1), 16 cases of degree III-V (group A2) according to Meyerding standard, including 17 cases of grade A, 7 cases of grade B, 9 cases of grade C, and 6 cases of grade D according to Frankel scoring system. In group B, there were 21 cases of degree I-II (group B1) and 20 cases of degree III-V (group B2), including 20 cases of grade A, 7 cases of grade B, 11 cases of grade C, and 3 cases of grade D. All cases were treated with posterior spinal cord decompression and reduction, with internal fixation by pedicle screw-rod system and transforamen lumbar interbody fusion. Results The blood loss was (407.4 ± 24.3) mL in group A1 and (397.4 ± 8.2) mL in group B1, showing no significant difference (t=1.804, P=0.078); the blood loss was (1 046.9 ± 128.6) mL in group A2 and (494.4 ± 97.7) mL in group B2, showing significant difference (t=14.660, P=0.000). All 80 patients were followed up 2 years to 2 years and 6 months (mean, 2 years and 3 months) with satisfactory results in spinal cord decompression and reduction, and bony fusion was achieved at 12 months. There was no significant difference in the vertebral canal volume, vertebral height, and Cobb angle at both pre- and postoperation between 2 groups (P gt; 0.05). No loosening or breakage of screws and rods occurred. At 12 months after operation, the cure rates were 47.83% (11/23) in group A1 and 19.05% (4/21) in group B1, showing significant difference (χ2=4.046, P=0.044); the cure rates were 12.50% (2/16) in group A2 and 10.00% (2/20) in group B2, showing no significant difference (χ2=0.056, P=0.813). There was no significant difference (χ2=0.024, P=0.878) in the cure rates in the patients at grades A and B before operation between group A (12.50%, 3/24) and group B (11.11%, 3/27); but there was significant difference (χ2=5.992, P=0.014) in the cure rates in the patients at grades C and D before operation between group A (66.67%, 10/15) and group B (21.43%, 3/14). Conclusion Emergency operation of posterior pedicle screw-rod system for treatment of thoracolumber spine fracture and dislocation with spinal cord injury can provide good reduction, rigid fixation, and high fusion rate, so it is asafe and effective treatment method.
Objective To elucidate the new development and effects of three-dimensional correction techniques of idiopathic scol iosis (IS). Methods The related home and abroad l iterature concerning three-dimensional correction techniques of IS was extensively reviewed. Results With more and more attention to three-dimensional correction of IS, all kinds of surgery and developed techniques of correction are applied to the correction of IS. The effects of three-dimensional correction of IS are satisfied. Conclusion With more knowledge about IS and more developed theory of correction, more safe and effective techniques of correction is therefore the hot spot for future study.