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Objective To compare the rigidity at upper thoracic spine among the anterior transpedicular screw-plate system (ATPSPS),posterior transpedicle screw-rod system (PTPSRS) and anterior vertebral body screw-plate system (AVBSPS).Methods Twelve embalmed cadaver specimens were divided into three groups.The specimens in each group were randomly allocated to use the above 3 different internal fixation devices for conducting fixation.The stiffness of each specimen on the directions of axial compression,flexion and extension,and left and right lateral bending was detected under original status.All specimens conducted the simulated corpectomy of T2 (damage status).Then the rigidity on various directions was re-detected on the damage status.The corresponding internal fixation system was selected for conducting the install and fixation according to the grouping results.The intra-group and inter-group rigiditieson different directions were compared amongoriginal status,damage status and after internal fixation.Results The rigidities on different directions under original and damage statushad no statistical difference among various groups (P＜0.05).After conducting fixation in each group,the rigidity after fixation on different directions had statistically significant difference among groups(P＜0.05).The stiffness of anterior flexion in the ATPSPS group was greater than that in the other two groups (P＜0.05).The rigidity of axial compression and extension in the PTPSRS group was greater than that in the other two groups,the difference among groups was statistically significant (P＜0.05).The stiffness of lateral bending in the AVBSPS group was smaller than that in the other two groups,the difference was significant (P＜0.05),but the difference between the other two groups had no statistical significance (P＞0.05).Conclusion The rigidity of ATPSPS in all directions is higher than that of AVBSPS.The anterior flexion rigidity is greater than PTPSRS,and the axial compression and extension rigidity are less than PTPSRS,but the lateral bending rigidity is equivalent to PTPSRS.
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OBJECTIVE: To analyze the pressure change and distribution of the intervertebral disc of upper thoracic spine in vertical pressure and 5° flexion, extension, or lateral bending.
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[Objective]To investigate the method of anterior transsternal approach for the patients with upper thoracic spine diseases and the clinic results.[Method]Six cases upper thoracic spinal diseases,1 case of C7/T1 grade V dislocation,1 case of T1、2 TB,2 cases of upper thoracic tumor,1 case of T2 fracture and 1 case of T2、3 disc prolapse,were treated with the anterior transsternal approach operation since Oct.2001.The lesions areas were exposed via partial or complete sternotomy.The relative articles were reviewed.[Result]The average follow-up was 12.4 months(range from 6 to 22 months,except the died one).The case of C7/T1 grade V dislocation died of respiratory tract obstruction and one case of malignant schwannoma recurred 6 months post-operation.Good results were obtained in the other 4 cases.No operative complication happened in all cases.[Conclusion]While the transthoracic lateral approach cannot expose the upper thoracic spine clearly,the anterior cervical approach cannot expose the T2、3 clearly also.The anterior transsternal approach can provide a safe access to the lesions located on the upper thoracic spine above T4.
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OBJECTIVE: The goal of study is the evaluation of clinical and radiological outcome of thoracic pedicle screw fixation and fusion in unstable thoracic spine fractures. METHODS: The authors retrospectively studied 21 patients with unstable thoracic fractures received thoracic pedicle screw fixation and fusion from 1995 to 2001. We analyzed the pre- and postoperative neurological finding(Frankel functional classification), radiological finding(Sagittal index: SI, Percentage of anterior body compression:ABC), complications, and displacement of screws. RESULTS: All five Frankel E grades remained E grade, 7 of 10 incompletes improved, and 6 complete deficits remained complete. No patients sustained an increase in neurologic deficit. These 21 patients had a mean preoperative SI as 19.3 degrees, which was corrected to 14.4 degrees after operation. After 6 months follow-up, the SI was 14.2 degrees And those had an mean preoperative ABC as 53.8% which was corrected to 34% after operation. At 6 months. the mean ABC was 34.4%. A statistically significant difference existed between the preoperative, postoperative and follow-up SI and ABC. The complications were respiratory and urinary tract infection, decubitus et al., but the hardware failure was not occurred. The cortical violation of pedicle screw in 4 patients who had mid-upper thoracic fractures was 26.7%, but the displacement was less than 2 millimeter and any neurological, cardiovascular, or pulmonary injury were not revealed. The bone fusion and stabilization was successful in all patients. CONCLUSION: Pedicle screw fixation and fusion is an effective and safe method in unstable thoracic spine fractures, because of high fusion rate, good neurological and radiological outcome and low complication rate. Mild displacement of pedicle screw does not affect the clinical outcome. So, pedicle screw fixation can be an acceptable procedure in unstable mid-upper thoracic spine fracture or dislocations.
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Humans , Joint Dislocations , Follow-Up Studies , Lung Injury , Neurologic Manifestations , Retrospective Studies , Spine , Urinary Tract InfectionsABSTRACT
Anterior exposure to the upper two thoracic vertebrae is technically difficult with transcervical approach. The authors used a transstermal biclavicular approach to the T1 metastatic adenocarcinome in a 47 year old patient. The advantages of this approach are that : 1) it levels the insertion of the sternocleidomastoid muscles intact and prevents the complication of respiratory problem, 2) it gives most wide surgical field among the other similar approaches, and 3) this procedure is not transpleural but transmediastinal approach.