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<p><b>OBJECTIVE</b>To investigate the feasibility and therapeutic effect of subcutaneous pedicle screw-rod system with modified placement in treatment of Tile B pelvic fractures.</p><p><b>METHODS</b>From June 2014 to August 2015, 14 patients with Tile B pelvic fractures were treated by subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle. There were 8 males and 6 females, aged from 23 to 65 years with an average of 42 years. Operative time, intraoperative blood loss, fracture healing and postoperative complication were observed and clinical effects were evaluated by Matta reduction standard and Majeed score.</p><p><b>RESULTS</b>All patients were followed up from 8 to 15 months with an average of 10.5 months. Operative time was 25 to 45 min with an average of 32 min;intraoperative blood loss was 10 to 35 ml with an average of 18 ml. All fractures got primary healing and healed time was 9 to 14 weeks with an average of 12.5 weeks. No postoperative incision infection, internal fixation failure and ectopic ossification were found, 4 cases occurred unilateral lateral femoral cutaneous nerve injury and 1 case occurred unilateral femoral nerve paralysis, but all restored finally. According to Matta criteria, reduction was excellent in 7 cases, good in 5 cases, fair in 2 case. According to Majeed score system, the functional evaluation at last follow-up was excellent in 5 cases, good in 7 cases, fair in 2 cases with the average score of 81.50±8.05.</p><p><b>CONCLUSIONS</b>Subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle have advantages of strong reduction, less trauma and complications, and is a promising surgical method in the treatment of Tile B pelvic fractures.</p>
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Objective To investigate the validity of screw-rod system for fixing pelvic fractures by comparing the biomechanical behaviors from using screw-rod system or steel plate for fixing Tile B2 type pelvic fractures. Methods The finite element models of normal pelvis including ligaments, and Tile B2 fractured pelvis fixed by different screw-rod fixations (2 screws at fractured side, 3 screws at fractured side and at healthy side), and steel plate fixation were established. The vertical load (500 N) was applied on the upper terminal plate of the first body of the sacrum to simulate pelvis load during double-leg standing, single-leg standing and sitting. The displacement and stress distributions on normal pelvis and fractured pelvis with screw-rod fixation or with steel plate fixation were compared and analyzed. Results Both the screw-rod system and steel plate could effectively fix the fractured pelvis, and the fixation models showed similar displacement and stress distribution as normal pelvis. The largest displacement of fractured pelvis with 3-screw fixation on the diseased side was smallest under each working condition, and its stress level was also obviously lower than that of the other internal fixation models. During double-leg standing, compared with 2 screws fixation, 3 screws at healthy side fixation, and steel plate fixation, the Von Mises stress for 3 screws at fractured side fixation was reduced by 30.4%, 20.8%, 20.3%; during single-leg standing, the Von Mises stress for 3 screws at fractured side fixation was reduced by 31.8%,25.4%,18.5%; during sitting, the Von Mises stress for 3 screws at fractured side fixation is reduced by -6.5%,28.0%,61.1%,respectively. Conclusions The screw-rod system can fix Tile B2 pelvic fracture effectively, especially for 3-screw fixation on the fractured side. The results can provide the theory basis for clinical treatment of pelvic fracture.
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Objective To observe the feasibility of posterior internal fixation with pedicle screw rod system for upper cervical vertebra injury. Methods 16 patients with upper cervical vertebra injury accepted posterior pedicle screw system internal fixation were reviewed. Re-sults Venous plexus behind C2 damaged in operation in a case, who needed a microscope for hemostasis. No complication, such as neurologi-cal symptoms worse, cerebrospinal fluid leakage, hematoma and infection of incision happened post operation. The neurological symptoms improved 81.8%in all the 7 cases who complained before operation. No complication was found in the follow-up 3 to 18 months after dis-charge. Their activities of upper cervical was basically unaffected. Conclusion Posterior internal fixation with pedicle screw rod system can provide stable support for patients with upper cervical injury.
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@#Objective To observe the feasibility of posterior internal fixation with pedicle screw rod system for upper cervical vertebra injury. Methods 16 patients with upper cervical vertebra injury accepted posterior pedicle screw system internal fixation were reviewed. Results Venous plexus behind C2 damaged in operation in a case, who needed a microscope for hemostasis. No complication, such as neurological symptoms worse, cerebrospinal fluid leakage, hematoma and infection of incision happened post operation. The neurological symptoms improved 81.8% in all the 7 cases who complained before operation. No complication was found in the follow-up 3 to 18 months after discharge. Their activities of upper cervical was basically unaffected. Conclusion Posterior internal fixation with pedicle screw rod system can provide stable support for patients with upper cervical injury.
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STUDY DESIGN: Prospective study. OBJECTIVES: To analyze the outcome of posterior reduction and fixation with the AO internal fixator and with the screw-rod system in unstable thoracolumbar fractures and to investigate differences in effectiveness between the two methods. SUMMARY OF LITERATURE REVIEW: In unstable thoracolumbar fractures, fixation with the AO internal fixator is an effective method for posterior reduction. However, the results of correction are quite variable. MATERIALS AND METHODS: We analyzed 51 patients with unstable thoracolumbar fractures who underwent correction through posterior approach between 1997 and 2003. We divided the patients into two groups: Patients in Group A (25 cases) were treated with the AO internal fixator, and patients in Group B (26 cases) were treated with the screw-rod system. We added transpedicular bone grafts for 17 patients in Group A. We evaluated correction of deformity (anterior and posterior height of vertebral body, sagittal index, disc height), loss of correction, spinal canal clearance, and neurological recovery. RESULTS: Comparing correction of deformity, we saw better results in Group A than in Group B in regards to sagittal index and anterior height of vertebral body. However, we saw a higher degree of correction loss in the anterior height of the vertebral body in Group A. We grafted autogenous bone into the fracture site by transpedicular approach for 17 patients in Group A. We saw less correction loss in the anterior vertebral body height and sagittal index. In regard to spinal canal clearance, we saw better results in Group A (18%) than in Group B (10%). As for neurological recovery, we could not find any statistically significant difference between the two groups. CONCLUSIONS: Through an operative procedure, we could achieve better results in restoration of anterior vertebral height and canal clearance with the AO internal fixator system. Further study is necessary to keep the reduced state of vertebral height.
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Humans , Body Height , Congenital Abnormalities , Internal Fixators , Prospective Studies , Spinal Canal , Surgical Procedures, Operative , TransplantsABSTRACT
PURPOSE: We performed 65 cases of posterior fusion surgery for cervical and/or high thoracic lesions using a polyaxial screw-rod system. PATIENTS AND METHODS: A total of 486 screws were implanted in 65 patients. RESULTS: Fixation of the screws was carried out over an average of 2.9 spinal segments. Upon evaluation by postoperative CT scans, twelve (2.5%) screws had suboptimal trajectories but two of these revealed radiculopathy in one patient and required screw repositioning. No vascular sequelae resulted. There has been no segmental motion in any of the cases to date. As for other complications, there was one case of dural tearing and two cases of lateral mass fractures. There were no infections or other wound healing problems or hardware failures. No patients had neurological deterioration after surgery. There were statistically significant improvements in the mean Neck Disability Index (NDI) scores and Visual Analogue Scale (VAS) scores in the preoperative and late postoperative follow-up evaluations. Although further studies are required to establish the long-term results of fusion rates and clinical outcomes. CONCLUSION: We cautiously suggest that the posterior polyaxial screw-rod system can be safely used as a primary or additional fusion method in this risky region. The successful and safe use of this method is dependent on a precise preoperative surgical plan and tactics for ensuring safe screw fixation.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Bone Screws , Cervical Vertebrae/diagnostic imaging , Recovery of Function , Reproducibility of Results , Spinal Diseases/physiopathology , Spinal Fusion/instrumentation , Thoracic Vertebrae/diagnostic imaging , Time Factors , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
PURPOSE: To analyze the results of posterior reduction with AO internal fixator or screw-rod system in thoracolumbar fracture and to find an adequate method of treatment. MATERIALS AND METHODS: We analyzed 40 cases of unstable thoracolumbar fractures who were operated with posterior approach without additional anterior approach. All cases were divided into two groups by the instrument used: Group A (25 cases) with AO internal fixator and Group B (15 cases) with screw-rod system. They were classified according to AO classification. RESULTS: There was no significant difference in correction and maintenance of sagittal index among types of AO classification except neurological recovery which was better in Type A. AO internal fixator had better results than screw-rod system in correction and maintenance of sagittal index, but no difference in neurological recovery. Eleven cases had more than 5 degrees of correction loss at final follow-up. In these cases, we found several findings; decreased vertebral body height, decreased disc height, bony collapse around screw at superior segment, metal loosening between rod and screw and metal breakage of screw. CONCLUSIONS: We concluded that AO internal fixator was good for the posterior reduction of thoracolumbar fracture in this study. But we think that continuous follow-up and further study are needed.