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Early Posterior Spinal Canal Decompression and Circumferential Reconstruction
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for Rotationally Unstable Thoracolumbar Burst Fracture with Neurologic Deficit
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Guo-Quan Zheng1, Yan Wang1, Pei-Fu Tang1, Xue-Song Zhang1, Yi-Zhu Guo1, Sheng
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Tao1
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1: Department of Orthopaedics, Chinese PLA General Hospital
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Beijing 100853, PR China.
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Corresponding author: Prof. Yan Wang, Department of Orthopaedics, Chinese PLA
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General Hospital, Beijing 100853, PR China.
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E-mai: [email protected]
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Telephone: ＋86-10-66939439
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Fax：＋86-10-88219862
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Summary of Background Data Various treatment of neurologically involved unstable
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thoracolumbar burst fractures have been described, including anterior, posterior and
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combined anteroposterior surgery. Among these, the combination of anterior and
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posterior instrumentation provides the most stable reconstruction. However, the use of
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both approaches on a trauma patient may increase the morbidity.
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Methods
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thoracolumbar burst fracture in our institution underwent a single stage posterior
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approach for spinal canal decompression in combination with circumferential
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reconstruction. The operation technique includes resection of the posterior elements,
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partial resection of the injured vertebra and disc, reconstruction of the anterior column
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with Titanium mesh cage, posterior instrumentation with pedicle screws, and posterior
From March 2005 to January 2007, 6 patients (5 males, 1 females) with
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spinal fusion. Preoperative and postoperative X-ray films were reviewed and changes of
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Cobb angle of thoracolumbar spine were documented. Intraoperative, postoperative and
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general complications were registered.
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Results
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According to the Frankel grading system, 1 patient had complete, 5 patients had
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incomplete neurologic deficits. The mean follow-up was 21.7±9.1 months (range, 14 to
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48 months). The mean operation time was 248 minutes (range, 208-316 minutes), the
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average volume of intraoperative blood loss was 2453 ml (range, 1800-3480 ml), the
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average vertebral body height loss at the injured level was 56% (range, 48–70%), and the
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average Cobb angle in sagittal plane was improved from 39.8° before surgery (range,
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34~46°) to 4.8° (range, -2 ~12°) immediately after surgery. Postoperatively, there was an
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epidural hematoma in one patient. Bony union after stabilization was obtained in all
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patients, without loosening or breakage of screws. Loss of correction (5°) was seen in 1
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patient at the 6th month owing to the subsidence of the Titanium mesh cages into the
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vertebra. All patients with incomplete neurologic deficits improved at least 1 Frankel
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grade.
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Conclusion Single stage posterior vertebra resection in combination with circumferential
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reconstruction is a new option to manage severe thoracolumbar burst fracture.
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【Key words】posterior approach; burst fractures; thoracolumbar vertebra; kyphosis;
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osteotomy
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Introduction
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The involved levels were L2 in 1 patient, L1 in 4 patients and T12 in 1 patient.
Most thoracolumbar burst fractures occur from the failure of the anterior column
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under compression, however, the posterior osteoligamentous complex remains intact and
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provide mechanical stability. The majority can be treated successfully without an
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operation. When deemed necessary, however, numerous surgical techniques have been
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described, including indirect decompression (ligamentotaxis) by the use of distraction
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instrumentation such as Harrington rods and pedicle screw devices [1,2], fracture
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reduction without spinal canal decompression[3], and decompression and arthrodesis
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without instrumentation.[4].
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Rotationally unstable burst fractures (AO-C type), in contrast, are characterized by
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osteoligamentous posterior column disruption, large reductions in vertebral body height,
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loss of anterior column support and frequently with extensive canal compromise and
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neurological deficits [5,6]. Although the need for surgical decompression and
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stabilization in cases with incomplete neurological deficit has been widely advocated, the
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optimal approach remains controversial.
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For these unstable neurologically involved fractures, a combination of both anterior
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decompression and posterior instrumentation is frequently recommended for optimal
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stability [7]. However, the extensive surgical procedures including the anterior approach
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may increase morbidity [8-11], especially with traumatized thoracic or peritoneal cavities.
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Theoretically, stabilization of both columns through a posterior approach would avoid
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these risks, shortcomings and facilitate rehabilitation. Recently authors have reported
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their experience with similar methods. Sciubba [12] reported on 7 patients who
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underwent vertebrectomy via a bilateral modified costotransversectomy approach
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followed by posterior placement of an anterior distractible cage, reduction of the
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deformity via cage distraction, and supplemental dorsal instrumentation. Ayberk [13]
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reported on eight patients with burst fracture involving the thoracic or lumbar vertebrae
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by the application of anterior and posterior stabilization instruments through only the
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posterior approach.
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We have developed a transpedicular technique, which was originally designed for
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severe scoliosis and kyphoscoliosis [14], to perform a column resection by a posterior
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only approach, and applied this to correct severe thoracolumbar burst fractures [15]. The
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purpose of this paper was to introduce this reconstruction technique and its early
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follow-up results.
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Patients and Methods
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Patients From March 2005 to January 2007, 6 patients (5 male, 1 female) presented to
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our institute with a rotationally unstable burst fracture dislocation of the thoracolumbar
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spine and neurologic compromise. The causes of injury were motor vehicle accident in 1
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patient and falling from a height in 5.The fractures were located at T12 in 1 patient, L1 in
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4 patients, L2 in 1 patient. All had compressive failure of the anterior columns as viewed
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on CT scan with posterior ligamentous disruption, including laminar fractures, and a
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spinous process split. All patients were classified as rotationally unstable thoracolumbar
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burst fracture, 2 were Types C2, and 4 were Types C3. All patients were treated with
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steroid protocol and were operated within 48 hours. Neurological deficits were assessed
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by the operating surgeons according to Frankel grade system (Table 1).
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Operative Technique The skin incision was made in the midline overlying the site of the
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fracture and extending above and below approximately two vertebral levels.
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Instrumentation with pedicles screws was performed to achieve temporary stability of the
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spine before the dorsal decompression was accomplished. Transpedicular decompression
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was afforded by resecting and removing the fractured bony fragments piecemeal with a
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high-speed drill. The medial wall of pedicle and the anterior lateral wall of vertebra must
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be preserved during drilling to prevent neural or vascular injury, respectively. The
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preservation of anterior and lateral wall of vertebra may help to form a bony fusion as
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well. Care must especially be taken when removing the retropulsed bone fragments to
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avoid dural laceration or injury to the spinal cord. After the resection of vertebra body,
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the resection was extended to adjacent intervertebral discs. The lower surface of upper
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vertebra body and the upper surface of the caudal vertebra are well exposed, and
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reconstruction of anterior column with Titanium mesh cage is performed [Fig.2]. During
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the procedure, if present, the posterior longitudinal ligament must be preserved.
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Compression of the posterior instrumentation can simultaneously be applied when the
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stability of anterior column is reconstructed with the Titanium mesh cage. Autologous
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graft is harvested from the dorsal iliac crests. Then, the facet arthrodesis and decortication
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of the transverse process, lamina, and pars interarticularis were performed for dorsolateral
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spinal fusion. A wake-up test was applied at the end of instrumentation in all cases. A
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drainage tube was inserted before the incision was closed. Two months after surgery, the
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patients were allowed to walk with a total contact thoracolumbosacral orthosis.
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Follow-up Series postoperative radiographs and clinical examination were obtained at 3,
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6, 12 and 24 months (Table 1).
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Radiologic Assessment Fracture kyphosis was measured on lateral radiographs in the
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neutral position, before and immediately after surgery, 1 year after surgery, and at the
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time of the final follow-up examination [Fig.1,3-5]. The kyphosis angle was measured
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with the Cobb method from the superior endplate of the vertebral body just above the
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fracture to the inferior endplate of the vertebral body below the fracture.
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Complications and Technical Outcome Intraoperative, postoperative and general
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complications were registered.
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Result:
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The mean operation time was 248 minutes (range, 208-316 minutes). The average
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volume of intraoperative blood loss was 2453 ml (range, 1800-3480 ml). Clinical
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follow-up evaluation was performed on all patients, and no patient was lost to follow-up.
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Radiographic outcomes The canal compromise before surgery, based on preoperative
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CT scan, ranged from 50 to 70%. Average vertebral body height loss at the injured level
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was 56% (range, 48–70%). The average Cobb angle in sagittal plane was improved from
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39.8° before surgery (range, 34~46°) to 4.8° (-2~12°) immediately after the surgery.
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Bony union after stabilization was obtained in all patients. During the follow-up, no
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loosening or breakage of pedicle screws was found. Loss of correction (5°) was seen in 1
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patient at the 6th month owing to the subsidence of the Titanium mesh cage into the
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vertebra.
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Clinical results According to the Frankel grading system pre-operatively, 1 patient had a
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complete, and 5 patients had an incomplete neurological deficit. All 5 patients with
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incomplete neurologic deficits improved at least with 1 Frankel grade at final follow-up.
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One patient with Frankel Grade A paraplegia had no improvement. (table 1).
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Complications There were no major acute complications such as death, paralysis, or
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infection. No surgical complications such as CSF leak, hemothorax and pleural effusion,
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and neurologic injury were found. There was one patient suffered postoperative epidural
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hematoma, and it was drained with CT guided aspiration. Loss of correction (5°) was
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seen in 1 patient in the 6th month owing to the subsidence of the Titanium mesh cage into
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the vertebra. Fortunately, no further correction loss was seen in any patient at the final
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follow-up examination. No others complication, such as pseudarthrosis, screw
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misplacement, and hardware failure were detected during the follow-up period.
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Discussion
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Rotational fracture-dislocation (AO Type C) represents the anterior column and posterior
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osteoligmentous columns are structurally compromised. In addition, these injuries have
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the highest rate and most severe degree incidence of neurological involvement. Therefore
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operative treatment has been widely recommended.
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In unstable injuries such as these (AO-Type C), reconstruction of the anterior and
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posterior columns is essential for complete stabilization of the injured spine and
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restoration of the neural canal [16,17]. The goals of surgery thus include decompression
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of neural elements, restoration of vertebral height, alignment, stabilization and early
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mobilization.
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In the presence of a neurologic deficit, particularly an incomplete spinal cord lesion
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from anterior compressive pathology, some form of anterior decompression is typically
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indicated [18,19]. The transthoracic or thoracoabdominal anterior approach is an indirect
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methods. However, it’s an invasive one associated with increased blood loss, pulmonary
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complications including pleural effusion and hemothorax, risk of spinal cord ischemia,
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and injury to the major vessels. [20-23].
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We have shown that our transpedicular spinal osteoectomy technique, which
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heretofore was used in severe scoliosis and kyphoscoliosis, can effect anterior vertebral
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column resection, significant canal clearance and segmental stabilization all from a
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posterior approach. The technique works around the spinal cord for both 360-degree
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decompressions combined with posterior osteoligmentous reconstruction with segmental
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pedicle instrumentation.
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The major advantages of a posterior only approach are the relative safety, familiar
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anatomy for most spine surgeons, facilitation of the placement of stabilization devices,
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and the ability to reconstruct the posterior tension band. Another significant advantage of
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this method is absence the morbidity risks of the anterior approach. In the setting of spine
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trauma, avoidance of potentially injured thoracic or peritoneal cavity contents is of great
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importance.
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A technical note: For rotationally unstable burst fractures, removing the dorsal
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elements may further destabilize an already compromised spine, therefore, we
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recommend temporary stability with pedicle screws before the dorsal and ventral
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decompression is undertaken.
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The potential pitfall of this method is that the osteotomy site is at an actualy
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fractured vertebrae, which may potentially increase the volume of blood loss. In addition,
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it is a technically demanding procedure, and it must be performed by experienced
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surgeons, with which may prevent it wide application. Also this study reviewed a
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relatively small number of series cases, with no comparison and no control. Further
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comparative studies with traditional techniques are therefore needed.
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Conclusion
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A single stage posterior based vertebral resection in combination with circumferential
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reconstruction is a viable method to safely manage severe unstable thoracolumbar burst
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fracture with neurological deficits, while potentially reducing operation time, risks and
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perioperative morbidity.
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Reference:
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1. Yazici M, Atilla B, Tepe S, et al. Spinal canal remodeling in burst fractures of the
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thoracolumbar spine: a computerized tomographic comparison between operative
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and nonoperative treatment. J Spinal Disord. 1996; 9:409–413.
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2. Sjostrom L, Karlstrom G, Pech P, et al. Indirect spinal canal decompression in burst
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5. Benson DR, Burkus JK, Montesano PX, et al. Unstable thoracolumbar and lumbar
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burst fractures treated with the AO fixateur interne. J Spinal Disord.1992; 5:335–343.
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6. Hardaker WT, Cook WA, Friedman AH, et al. Bilateral transpedicular
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thoracolumbar burst fractures. Spine. 1992; 17: 162-171.
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796-802.
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8. Kaneda K, Taneichi H, Abumi K, et al. Anterior decompression and stabilization
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12. Sciubba DM, Gallia GL, McGirt MJ et al. Thoracic kyphotic deformity reduction
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13. Ayberk G, Ozveren MF, Altundal N, Tosun H, Seckin Z, Kilicarslan K, Kaplan M.
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Three column stabilization through posterior approach alone: transpedicular
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placement of distractable cage with transpedicular screw fixation. Neurol Med Chir
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(Tokyo). 2008; 48: 8-14.
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14. Wang Y, Zhang YG, Zhang XS, et al. A single posterior approach for multilevel
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1901-1909.
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21. Kaneda K, Taneichi H, Abumi K, et al. Anterior decompression and stabilization
12
with the Kaneda device for thoracolumbar burst fractures associated with
13
neurological deficits. J Bone Joint Surg Am. 1997; 79: 69–83.
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Legends
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Fig. 1 A 27-year-old man with burst fracture of L1 as a result of falling from height was
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illustrated. The initial anterioposterior (A) and lateral radiograph (B) demonstrated a
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typical L1 vertebral body burst fracture with retropulsion of superior-posterior aspect of
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the vertebral body into the spinal canal. CT scan (C) demonstrated superior endplate
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fracture, kyphotic angulation, and posterior cortical bone retropulsion, rotation of the
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spine at the level of the fracture. The anterior and posterior columns were damaged
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severely, so it is necessary to reconstruct these elements for stability. This patient had
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severe neurological deficit with a Frankel grade B on admission.
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Fig. 2 A single posterior approach for circumferential surgical reconstruction with a
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titanium mesh cage and pedicle screw fixation. Temporary stability of the spine was
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created with pedicle screws instrumentation in left side before the dorsal and ventral
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decompression.
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Fig. 3
The anterioposterior (A) and lateral radiograph (B) postoperatively and sagittal
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reconstruction of a lumbosacral spine CT scan demonstrated that the alignment of the
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lumbar spine was very good, and no residual bony fragment was seen in spinal canal.
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Fig. 4 X-ray 2.5 years postoperatively shows that no correction lose, instrumentation
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failure can be detected, and perfect bony fusion is achieved.
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Fig. 5 CT 3-D reconstruction 2.5 years postoperatively show the whole morphous of
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injured vertebra was reconstructed (A-C), and volume rendering technique show that the
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Titanium mesh cages inside the injured vertebra brought an adequate support of anterior
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column (D). Bony fusion can prevent the collapse and displacement of Titanium mesh
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cages as well. No remarkable change in neurological condition was seen during the
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follow-up period, while the thoracolumbar pain was relief.
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Table 1 The data of patients.
Patients
Injury vertebrae
Frankel grade
Pre-O post-O
Cobb angle (°)
Pre-O post-O
Pain scale*
Blood lose(ml) complication
Pre-O post-O
1
L1
B
C
38
0
3
1
2400
2
L1
B
D
46
12
4
2
2380
3
T12
A
A
34
-2
3
1
1800
4
L1
D
E
42
5
2
1
3480
5
L2
C
D
44
8
3
1
2850
6
T12
D
E
35
6
4
1
2230
Cage sinking, 5°correction Loss
epidural hematoma
“pain scale *”: according to Denis Pain Scale: 1, no pain; 2, occasional minimal pain, no need for medication; 3, moderate pain,
occasional medications, no interruption of work of activities of daily living; 4, moderate-to-severe pain, occasionally absent from
work, significant changes in activities of daily living; 5, constant, severe pain, chronic pain medications.
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