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Objective To analyze the operation time,radiation exposure time and the screw placement accuracy of a newly-developed guiding chunnel-assisted percutaneous pedicle screw placement technique for thoracolumbar vertebral fractures not accompanied by nerve injury.Methods The clinical data of 35 patients with thoracolumbar vertebral fractures not accompanied by nerve injury,who were treated with newly-developed guiding chunnel-assisted percutaneous pedicle screw placement technique during the period from July 2010 to October 2012,were retrospectively analyzed.A total of 178 procedures of pedicle screw placement were performed in the 35 patients by the one and the same surgeon.The operation time and radiation exposure time of each pedicle screw placement procedure were recorded,and based on the findings of postoperative consecutive two CT scans of the operated vertebrae the screw placement accuracy was graded and evaluated.Results The technical success rate of screw placement was 100％.The mean time used for a single pedicle screw placement was (11.35±2.82) minutes,the average radiation exposure time was (8.06± 2.15) seconds.Screw placement accuracy of grade A was obtained in 156 screws (87.64％),grade B in 20 screws (11.24％),grade C in one screw (0.56％),and grade D in one screw (0.56％).Conclusion The newly-developed guiding chunnel-assisted percutaneous pedicle screw placement technique is very helpful in localizing the puncture point,in improving the screw placement accuracy,and in reducing both operation time and radiation exposure time.
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Pedicle screw fixation is biomechanically most reliable for reconstruction of the cervical spine, which can ef?fectively restore cervical sagittal profiles, provide rigid fixation and higher fusion rate. Because of the large individual differ?ences in cervical pedicle, vertebral artery and nerve root, preoperative evaluation should be individualized. Cervical pedicle screw techniques include freehand technique and the computer-assisted navigation technology developed recently. Although complications associated with cervical pedicle screw fixation cannot be completely obviated, they can be minimized by com?bination of sufficient preoperative imaging studies of the pedicles and meticulous surgical techniques of screw placement. Cervical pedicle screw fixation techniques have been used in the treatment of various cervical disorders, with fewer complica?tions and good clinical efficacy, and a wide range of clinical applications.
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OBJECTIVE: A variety of different pedicle screws entry point techniques are used for the lumbar pedicle screws placement. This study reported Kim's entry point of lumbar pedicle screws with free hand technique and the accuracy of this technique. METHODS: We retrospectively reviewed the 584 cases with free hand placed lumbar pedicle screw placement. The diagnosis included 491 cases with degenerative spine, 59 cases with trauma, 29 cases with metastatic disease, and 5 cases with scoliosis. A total of 2601 lumbar pedicle screws were placed, and the entry points of lumbar pedicle screws were the junction of proximal edge of transverse process and lamina. Incidence and extent of cortical breach by misplaced pedicle screw was determined by review of intra-operative and post-operative radiographs and/or computed tomography. RESULTS: Among the total 2601 lumbar free hand placed pedicle screws, 114 screws (4.4%) in 79 patients (13.5%) were repositioned screws with suspected screw malposition during operation, and 37 screws (1.4%) in 31 patients (5.3%) were identified as moderate to severe breaching the pedicle after post-operative imaging studies. Among the patient with malpositioned screws, 3 patients showed nerve irritation sign of the lesion, and 2 cases were symptom improved after nerve block and conservative management, and 1 case was removed the screw after the failure of the treatment. CONCLUSION: Free hand pedicle screw placement based on external landmark with the junction of proximal edge of transverse process and lamina showed acceptable safety and accuracy and avoidance of radiation exposure.
Assuntos
Humanos , Mãos , Incidência , Bloqueio Nervoso , Estudos Retrospectivos , Escoliose , Coluna VertebralRESUMO
Thoracic pedicle screw fixation techniques are still controversial for thoracic deformities because of possible complications including neurologic deficit. Methods to aid the surgeon in appropriate screw placement have included the use of intraoperative fluoroscopy and/or radiography as well as image-guided techniques. We describe our technique for free hand pedicle screw placement in the thoracic spine without any radiographic guidance and present the results of pedicle screw placement analyzed by computed tomographic scan in two human cadavers. This free hand technique of thoracic pedicle screw placement performed in a step-wise, consistent, and compulsive manner is an accurate, reliable, and safe method of insertion to treat a variety of spinal disorders, including spinal deformity.