Thoracic Spine Trauma Research Articles

Biomechanics of thoracic short versus long fixation after 3-column injury

Posterior screw-rod fixation for thoracic spine trauma usually involves fusion across long segments. Biomechanical data on screw-based short-segment fixation for thoracic fusion are lacking. The authors compared the effects of spanning short and long segments in the thoracic spine. Seven human spine segments (5 segments from T-2 to T-8; 2 segments from T-3 to T-9) were prepared. Pure-moment loading of 6 Nm was applied to induce flexion, extension, lateral bending, and axial rotation while 3D motion was measured optoelectronically. Normal specimens were tested, and then a wedge fracture was created on the middle vertebra after cutting the posterior ligaments. Five conditions of instrumentation were tested, as follows: Step A, 4-level fixation plus cross-link; Step B, 2-level fixation; Step C, 2-level fixation plus cross-link; Step D, 2-level fixation plus screws at fracture site (index); and Step E, 2-level fixation plus index screws plus cross-link. Long-segment fixation restricted 2-level range of motion (ROM) during extension and lateral bending significantly better than the most rigid short-segment construct. Adding index screws in short-segment constructs significantly reduced ROM during flexion, lateral bending, and axial rotation (p < 0.03). A cross-link reduced axial rotation ROM (p = 0.001), not affecting other loading directions (p > 0.4). Thoracic short-segment fixation provides significantly less stability than long-segment fixation for the injury studied. Adding a cross-link to short fixation improved stability only during axial rotation. Adding a screw at the fracture site improved short-segment stability by an average of 25%.

Injuries significantly associated with thoracic spine fractures: A case–control study

To determine injuries significantly associated with traumatic thoracic spine (T-spine) fractures This was a case-control study undertaken in an adult trauma centre. Cases were patients admitted with a traumatic T-spine fracture between January 1999 and August 2007. Each case had two controls matched for sex, age (+/-5 years) and injury severity classification (major/minor). Data were collected from patient medical records and the trauma service database. Multivariate logistic regression was used to determine injuries significantly associated with T-spine fracture. Two hundred and sixty-one cases and 512 controls were enrolled. In both groups, mean age was 41 years and 70% of patients were male. Univariate analysis revealed a range of injuries that were significantly more common among the cases, especially cervical and lumbar spine injuries, sternal/scapular/clavicular/rib fractures, pneumo/haemothorax and pulmonary contusions (P < 0.01). Skull fractures and lower limb injuries were significantly more common among the controls (P < 0.01). Logistic regression analysis revealed that only cervical and lumbar spine injuries and rib fractures were positively associated with T-spine fracture (P < 0.001). Skull fractures and lower limb injuries were negatively associated with T-spine injury (P < 0.001). Cervical and lumbar spine injuries and rib fractures are significantly associated with T-spine fracture. The presence of these injuries should raise suspicion of concomitant T-spine injury.

Two children with traumatic thoracic spinal epidural hematoma

Traumatic spinal epidural hematomas in children are uncommon. Early diagnosis and prompt surgical evacuation is critical in these patients. We report two children with traumatic thoracic spine epidural hematomas with remarkable neurological recovery after surgical evacuation. Epidural hematoma with significant cord compression requires early diagnosis and emergency evacuation. This is crucial to expedite neurological recovery.

Rhythms of serum melatonin in rats with acute spinal cord injury at the cervical and thoracic regions

To evaluate the serum melatonin levels in acute period of the spinal cord injury (SCI) caused by trauma in the rats. Traumatic SCI induces many types of physiological and pathological damage, including hormonal level variations. Forty male Sprague-Dawley rats were divided randomly into four groups. In the control group, neither laminectomy nor SCI were performed; only a large laminectomy was performed without SCI in the sham group. In the cervical and thoracic spinal trauma groups, laminectomies at C5-6 and a T6-7 were performed, respectively, followed by clip compression of the spinal cord. Blood samples were drawn 2, 6, 12 and 24 h after the procedures and assayed immediately. The levels of melatonin in the neurotrauma groups were high in the first 2 h, but at the end of sixth hour, melatonin levels increased in sham-operated group, decreased in neurotrauma groups and did not change in control group. At the 12th hour, melatonin levels continued to decrease in thoracic group significantly. At the 24th hour, the melatonin levels decreased in the cervical, control and sham groups, whereas melatonin levels increased in the thoracic group. The present study revealed that (1) activation of endogen melatonin secretion of the organism starts immediately after the SCI, but it shows a great lowering trend between 2 and 6 h post-SCI, (2) the tetraplegic rats, which had complete injuries at the lower cervical spinal cord, could not produce enough melatonin secretion; on the contrary, the paraplegic rats, which had complete injury at the upper thoracic spinal cord, showed normal melatonin secretion.

Serum Leptin Levels Following Acute Experimental Spinal Cord Injury

Background/Objective: Spinal cord injury influences many hormones that are known to be involved in the modulation of neurotrophic, neurogenic, and neuroprotective events. Recent studies showed that leptin could be neuroprotective, enhancing neuronal survival in vitro and in vivo. The objective of this study was to evaluate the pattern of the serum leptin levels in rats during acute traumatic SCI.Methods: Forty male Sprague-Dawley rats were divided randomly into 4 groups. In the control group, neither laminectomy nor SCI was performed; only laminectomy was performed without SCI in the sham group. In the cervical and thoracic spinal trauma groups, laminectomies were performed following the same trauma procedure. Blood samples were drawn 2, 6, 12, and 24 hours after the procedures and assayed immediately.Results: In the first 2 hours, levels of leptin were similar in control and sham-operated groups and higher in neurotrauma groups (P < 0.05). At the sixth hour, leptin levels increased in the sham-operated group, decreased in the neurotrauma groups (P < 0.05), and did not change in the control group (P > 0.05). At the 12th hour, the levels of leptin increased in all groups (P > 0.05). At the 24th hour, they decreased in the control, sham-operated, and cervical groups (P < 0.05); levels did not change in the thoracic group (P > 0. 05). The decrease was higher in the control group than in the other groups (P < 0.05).Conclusions: Activation of endogenous leptin secretion started immediately after the SCI. The level of neurologic lesion (either cervical or thoracic regions) affected the levels of serum leptin differently, but with the exception of the first 12-hour period, this difference did not reach a statistically significant level.

Direct laryngoscopy and endotracheal intubation in the prone position following traumatic thoracic spine injury

Perioperative airway management in trauma victims presenting with penetrating thoracic spine injury poses a major challenge to the anesthesiologist. To avoid further neurological impairment it is essential to ensure maximal cervical and thoracic spine stability at the time of airway manipulation (e.g., direct laryngoscopy and endotracheal intubation). Airway management in the prone position additionally increases the incidence of cervical/thoracic spine injury, difficult ventilation, and difficult airway instrumentation. Although awake fiberoptic intubation of the trachea is considered the gold standard for airway instrumentation in patients with posterior thoracic/cervical trauma, this technique requires the patient's cooperation, special equipment, and extensive training, all of which might be difficult to accomplish in emergency situations. We herein present the first reported case of an adult trauma patient who underwent direct laryngoscopy and endotracheal intubation under general anesthesia in the prone position. Although the prone position is not the standard position for airway instrumentation with direct laryngoscopy and endotracheal intubation under general anesthesia, our experience indicates that this technique is possible (and relatively easy to perform) and might be considered in an emergency situation.

Accuracy and safety of pedicle screw fixation in thoracic spine trauma

The authors evaluated the accuracy of placement and safety of pedicle screws in the treatment of unstable thoracic spine fractures. Patients with unstable fractures between T-1 and T-10, which had been treated with pedicle screw (PS) placement by one of five spine surgeons at a referral center were included in a prospective cohort study. Postoperative computed tomography scans were obtained using 3-mm axial cuts with sagittal reconstructions. Three independent reviewers (C.B., V.S., and D.G.) assessed PS position using a validated grading scale. Comparison of failure rates among cases grouped by selected baseline variables were performed using Pearson chi-square tests. Independent peri- and postoperative surveillance for local and general complications was performed to assess safety. Twenty-three patients with unstable thoracic fractures treated with 201 thoracic PSs were analyzed. Only PSs located between T-1 and T-12 were studied, with the majority of screws placed between T-5 and T-10. Of the 201 thoracic PSs, 133 (66.2%) were fully contained within the pedicle wall. The remaining 68 screws (33.8%) violated the pedicle wall. Of these, 36 (52.9%) were lateral, 27 (39.7%) were medial, and five (7.4%) were anterior perforations. No superior, inferior, anteromedial, or anterolateral perforations were found. When local anatomy and the clinical safety of screws were considered, 98.5% (198 of 201) of the screws were probably in an acceptable position. No baseline variables influenced the incidence of perforations. There were no adverse neurological, vascular, or visceral injuries detected intraoperatively or postoperatively. In the vast majority of cases, PSs can be placed in an acceptable and safe position by fellowship-trained spine surgeons when treating unstable thoracic spine fractures. However, an unacceptable screw position can occur.

Timing of Thoracic Spine Stabilization in Trauma Patients: Impact on Clinical Course and Outcome

Optimal timing of stabilization for thoracic spine injuries in multiply injured patients is still controversial because additional lung injury occurs frequently. Early operation might benefit clinical course and outcome in these patients. We analyzed the German National Trauma Database (n = 8,057) and compared clinical parameters and outcome of patients with severe thoracic spine injuries (Abbreviated Injury Scale >2; n = 298) who underwent spine stabilization within 72 hours posttrauma (group I) or later (group II). In all, 95% of all patients had additional severe thoracic injuries such as lung contusion. In spite of comparable demographic data, patients in group I had a significant shorter intensive care unit (ICU) stay (median [range]: group I, 8 [0-237] days; group II, 16 [2-91] days; p = 0.001), shorter dependence on mechanical ventilation (group I: 2 [0-48] days; group II: 5 [0-91] days; p = 0.02), and shorter hospital stay (group I: 22 [1-255] days; group II: 31 [2-274] days; p = 0.048). Expected mortality calculated by Trauma and Injury Severity Score was significantly reduced in group I (calculated: 16%; documented: 6%; p < 0.05) but not in group II (19% versus 17%; p = NS). Almost 10% of all patients in the German National Trauma Registry had severe spine injuries. Severe thoracic injuries occurred in 95% of these patients with thoracic spine trauma. We provide further evidence that early stabilization of thoracic spine injuries in trauma patients reduces overall hospital and ICU stay and improves outcome. Thus early stabilization of thoracic spine injuries within 3 days after trauma appears to be favorable.

Timing of surgical stabilization after cervical and thoracic trauma

Appropriate timing for surgical intervention following destabilizing cervical or thoracic spine trauma remains controversial. Clinical investigators have failed to provide convincing evidence that the timing of surgery significantly affects neurological outcome in most situations. Nevertheless, early surgical stabilization of the injured spine has been shown to provide significant nonneurological benefits such as more rapid patient mobilization, facilitation of treating associated injuries, reduction in rates of pulmonary and pressure sore complications, reduction in duration of intensive care unit and hospital stays, and a decrease in overall medical costs. The findings of basic science studies have improved our understanding of the molecular and cellular events surrounding initial and secondary spinal cord injury (SCI), and analysis of these findings suggests that the early postinjury period may present a unique opportunity for meaningful intervention. This possibility has been supported by results obtained in animal studies that demonstrate the potential for improving functional outcome when surgical intervention is performed within a few hours following experimental SCI. Despite the absence of significant neurological recovery in most clinical studies, the results of most recent clinical studies strongly support the overall clinical benefits of early surgical intervention, particularly in the setting of unstable thoracic spinal column injury with associated SCI. Based on the best available scientific and clinical evidence, the authors report that it is therefore recommended that surgical stabilization be performed in as timely a fashion as possible, particularly for unstable thoracic spine trauma, within the constraints of the patient's overall medical condition and availability of appropriate resources.

SURGICAL APPROACH TO POSTTRAUMATIC THORACIC KYPHOTIC DEFORMITY

Objective. To define the effective surgical management of posttraumatic kyphotic deformities in the thoracic spine basing on experimental biomechanical and clinical studies Material and Methods. Experimental biomechanical study was performed in 30 spine specimens. Anterior wedge osteotomy and fixation of a specimen in a kyphotic position modeled kyphotic deformity. Deformity correction with various instrumentation systems was firstly performed by maximal extension of segments adjacent to kyphosis-producing block, and carried on after crossing of intervertebral anatomical structures. Clinical study consisted in X-ray and instrumental examinations of 80 patients operated on for thoracic spine trauma. The magnitude of true posttraumatic deformity was defined as a difference between measured Cobb angle and mean physiological kyphosis value in the studied spine level. Results. Deformity rigidity, character of spine mobilization at the level of correction and size of posttraumatic deformity are the most significant factors determining the efficacy of thoracic posttraumatic kyphosis correction. The study resulted in defining rational approach to surgical correction of posttraumatic deformities in the thoracic spine. Conclusion. Minor kyphotic deformities in the thoracic spine are effectively corrected by instrumentation without mobilization of the spine. Large unfixed kyphosis sometimes requires anterior mobilization. Cases with rigid posttraumatic kyphotic deformity should be operated on with combined mobilization of the spine.

The Effect of Early Spine Fixation on Non-Neurologic Outcome

It has been shown that spinal fracture fixation within 3 days can reduce the incidence of pneumonia, length of stay, number of ventilator days, and hospital charges. Our institutional protocol calls for surgical stabilization of spinal fractures within 3 days of admission. We hypothesized that compliance with an early spinal fracture fixation protocol (within 3 days of admission) would improve non-neurologic outcome in patients with spinal fractures. The trauma registry was queried for the period January 1988 through October 2001 to identify patients with spinal fractures requiring surgical stabilization. Patients were analyzed to determine the compliance with our protocol and to determine whether early spinal fixation can reduce the incidence of pneumonia, reduce length of stay, and reduce mortality. 1,741 patients with spinal fractures were identified. 299 (17.2%) required surgical stabilization. 174 (58.2%) had surgical stabilization within 3 days while 125 (41.8%) had surgical stabilization greater than 3 days from admission. There were no significant differences between the two groups with regards to age (37.9 versus 42.5), admission GCS (14.1 versus 13.9), or ISS (22 versus 20.8). The incidence of pneumonia was similar in both groups (21.8 versus 25.6%). The mortality was higher in the early group as compared with the late group (6.9 versus 2.5%), although it did not reach statistical significance. The hospital length of stay was significantly shorter (14.3 versus 21.1) for patients who had early spine fixation, however there was no statistically significant difference between the two groups with regards to intensive care unit length of stay (7.2 versus 7.9) or number of ventilator days (5.02 versus 1.9). Patients who were severely injured (ISS > 25) also had a significantly shorter hospital length of stay (19.6 versus 29.1) if they underwent early spinal fixation. Patients with thoracic spine injury and associated spinal cord injury had a significantly shorter HLOS (10.1 versus 30.5), ICULOS (2.3 versus 13.1), and lower incidence of pneumonia (6.5 versus 33.3%). Reasonable compliance with an early spinal fracture fixation protocol produced some outcome improvements in non-neurologic outcome. Early spine stabilization reduced hospital length of stay in all patients. Patients with thoracic spine trauma and a spinal cord injury had the greatest benefit in reduction of morbidity, HLOS and ICULOS from early stabilization. There was a trend toward poorer outcome in some groups with early spine stabilization. A rigid protocol requiring early surgical spine stabilization in all patients does not appear justified. Although early spine stabilization should be performed whenever possible to reduce hospital length of stay, the timing of this procedure should be individualized to allow patients with the most severe physiologic derangements to be optimized preoperatively.

Accuracy of Pedicle Screw Placement in Thoracic Spine Fractures

Transpedicular instrumentation in the thoracic spine is technically difficult because of small pedicle diameters. There are not many studies assessing in vivo accuracy, complications, and the revision rate of transpedicular screws in the thoracic spine. In this retrospective study 278 thoracic pedicle screws of 43 patients were assessed using a scoring system and postoperative computed tomography (CT) scans. 43 consecutive patients with traumatic thoracic spine fractures underwent posterior transpedicular reduction and fixation. The universal spine system was used for placement of 278 pedicle screws under fluoroscopic control. Fractures were classified according to the Magerl classification by plain radiographs and CT scans. Evaluation of pedicle screw placement was assessed by a scoring system from grade I to grade III. Revision rate of pedicle screws as well as pre- and postoperative neurologic status were analyzed. In the thoracic spine, vertebral body T7 was mainly fractured followed by T6 and T5. In 37 (86.0%) of 43 patients type C fractures and in three patients each type A and B fractures were determined, respectively. Of all 278 pedicle screws, 78.1% were inserted in pedicles T4–T9. The rate of optimally placed grade I screws was 84.5%. Grade II screws were scored in 6.8% and grade III screws in 8.6%. The revision rate of all pedicle screws was 5.0%, whereas 64.3% of these were grade III. None of the patients suffered neurologic or vascular structure compromise postoperatively. Although most pedicle screws were placed in pedicles of the middle thoracic spine where the pedicle width is smallest, most screws were optimally placed with grade I. The revision rate of pedicle screws was acceptable and associated with the grade of pedicle screw placement.

Endoscopic osteosynthesis after thoracic spine trauma: a report of two cases

Modern concepts of treating thoracic diseases suggest more and more the use of minimally invasive thoracoscopic techniques to reduce morbidity and save costs. For treatment of specific lesions at the thoracic spine, several thoracoscopic procedures have been performed successfully. The present report examines the feasibility of thoracoscopic osteosynthesis in two patients with ventral hyperextension injuries and anterior instability of the thoracic spine. After initial correction of the anatomical deformity, autologous bone was harvested from the anterior iliac crest. Using a ventral, thoracoscopic approach, the main location of the ventral, damaged spinal segment was identified by the covering pleural haematoma. After endoscopic ventral bone grafting, osteosynthesis was performed, using dynamic compression plates, cardan drills and screw drivers. The perioperative course was uneventful, and follow up examinations after 3 years and 9 months, respectively, revealed an unchanged stable spinal segment. Our results show thoracoscopic osteosynthesis to be technically possible, with a potential for yielding satisfying long-term results.

Thoracoscopic repair of thoracic spine trauma.

Modern concepts of treating thoracic and lumbar spinal trauma are based on posterior transpedicular fixation techniques which confer angular stability and instrument only a few levels of the spine. In addition, to prevent secondary losses in postoperative reduction of kyphotic deformities, transpedicular resection of torn discs, and inter- and intracorporeal bone grafting are included in the repair procedures for the entire damaged motion segment. However, due to the small size of the pedicles, a transpedicular approach to the injured vertebral body is not possible in the upper thoracic spine. Patients whose thoracic spine trauma is not serious enough to require ventral instrumentation through open thoracotomy, but who present with an unstable vertebral fracture, may profit from additional ventral bone grafting to stabilize the fracture. The present study examined the feasibility of thoracoscopic ventral bone grafting in seven patients with unstable fractures of the upper thoracic spine. For primary repair, we stabilized the fracture by using posterior transpedicular screw systems (rods or plates). Simultaneously, spongiosa was harvested from the posterior iliac crest and deepfrozen. Repair was completed a few days later via a ventral thoracoscopic approach. The main location of the ventral osseous defect was identified by intraoperative radiology. After mechanical removal of destroyed connective tissue and disc material, fusion was performed using the previously harvested spongiosa, which was placed into the intervertebral disc space and the anterior osseous defect. Our results show thoracoscopic bone grafting to be technically possible and associated with low morbidity, with a potential of yielding satisfactory long-term results.

Thoracic and lumbar spine trauma in children

Thoracic and lumbar spine trauma in children