Mini-open trans-spatium intermuscular versus percutaneous short-segment pedicle fixation for the treatment of thoracolumbar mono-segmental vertebral fractures / 中国骨伤

<p><b>OBJECTIVE</b>To compare the clinical effects and radiographic outcomes of mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits.</p><p><b>METHODS</b>From August 2009 and August 2012, 95 patients with thoracolumbar mono-segmental vertebral fractures without neurological deficits were treated with short-segment pedicle fixation through mini-open trans-spatium intermuscular or percutaneous approach. There were 65 males and 30 females, aged from 16 to 60 years old with an average of 42 years. The mini-open trans-spatium intermuscular approach was used in 58 cases (group A) and the percutaneous approach was used in 37 cases (group B). Total incision length, operative time, intraoperative bleeding, fluoroscopy, hospitalization cost were compared between two groups. Visual analog scale (VAS) and radiographic outcomes were compared between two groups.</p><p><b>RESULTS</b>All patients were followed up from 12 to 36 months with an average of 19.6 months. No complications such as incision infection, internal fixation loosening and breakage were found. In group A, fluoroscopy time was short and hospitalization cost was lower than that of group B (P<0.05). But the total incision length in group B was smaller than that of group A (P<0.05). There was no significant differences in operative time, intraoperative bleeding, postoperative VAS and radiographic outcomes between two groups (P>0.05). Postoperative VAS and radiographic outcomes were improved than that of preoperative (P<0.05).</p><p><b>CONCLUSION</b>The mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation have similar clinical effects and radiographic outcomes in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits. However, in this study, the mini-open trans-spatium intermuscular approach has a short learning curve and more advantages in hospitalization cost and intraoperative radiation exposure times, and is recommendable.</p>

Treatment of flexion-distraction thoracolumbar fractures by postural reduction with instrumental reduction / 中国骨伤

<p><b>OBJECTIVE</b>To study the curative effect of postural reduction with instrumental reduction in treatment of flexion-distraction thoracolumbar fractures.</p><p><b>METHODS</b>A retrospective study was performed on 43 patients with single thoracolumbar flexion-distraction fractures admitted from August 2009 to August 2011, included 28 males and 15 females with an average age of 44 years old (34 to 56 years old). All patients were treated with postural reduction with instrumental reduction. The kyphosis (Cobb angle) recovery of injured vertebral height and complication were analyzed. The visual analogue scale(VAS) and com-plications were followed up and recorded.</p><p><b>RESULTS</b>There was no difference in recovery of injured vertebral posterior height among preoperative, 1 week and 1 year after operation (P > 0.05). There were significantly difference in kyphosis (Cobb angle) and recovery of injured vertebral anterior height between preoperative and postoperative at 1 week (P < 0.05). There was no difference in kyphosis (Cobb angle) and recovery of injured vertebral anterior height between 1 week and 1 year after operation (P > 0.05). VAS significantly improved from preoperative (7.2 +/- 1.2) to (0.8 +/- 0.7) at 1 year after operation (t = 18.47, P < 0.001).</p><p><b>CONCLUSION</b>Postural reduction with instrumental reduction is effective for thoracolumbar flexion-distraction fractures and it is beneficial to the recovery of vertebral height and saggital alignment.</p>

Analysis of epidural hematoma formative reason and its preventive measure after anterior cervical operation / 中国骨伤

<p><b>OBJECTIVE</b>To explore the risk factors,preventive measure of epidural hematoma after anterior cervical operation.</p><p><b>METHODS</b>From June 2005 and December 2012, 1,452 patients underwent anterior cervical operation in our hospital. Epidural hematoma occurred in 5 cases after operation and the incidence rate was 0.34%. There were 4 males and 1 female with an average age of 46.4 years (ranged, 33 to 55); 3 cases with cervical myelopathy, 1 case with cervical myelopathy and C5 vertebral angeioma, 1 case with ossification of cervical posterior longitudinal ligament. The occurred time,main clinical situation,duration of symptoms,operative management of epidural hematoma were analyzed.</p><p><b>RESULTS</b>Five patients with epidural hematoma occurred within 24 h; the average interval between onset of symptoms and surgery was 4 h (ranged, 2 to 7). Operative treatment was accomplished in 5 cases by exploration and hematoma evacuation. There was significant improvement in all patients after reoperation. Epidural hematoma occurred again in one patient at 5 h after hematoma evacuation, and reoperation were performed to treat it. All patients were followed up from 6 to18 months with an average of 13.8 months. No recurrence was found.</p><p><b>CONCLUSION</b>Intensive care in 24 h postoperatively is important because of epidural hematoma often occurs in this period,especialy in the period of 6-8 h postoperativey. Clinical findings and MRI can early diagnose epidural hematoma and help treatment. Once it is identified and surgical evacuation would be performed on time.</p>

Transoral plate internal fixation for treatment of instability atlas fracture / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of transoral plate internal fixation for instability atlas fracture.</p><p><b>METHODS</b>A retrospective study was performed in eight patients with instability atlas fractures, who were treated by a transoral plate internal fixation from July 2007 to June 2011. There were 6 males and 2 females,with an average age of 39.5 years old ranging from 23 to 48 years. Among them, 5 case were falling injury, 3 cases were traffic accident injury. Three patients had bilateral fractures of the anterior arch (prehalf Jefferson fractures, Landells type I), 5 had anterior are fracture associated posterior are fracture (Half-ring Jefferson fractures, Landells type II), and 2 had anterior and posterior are fracture associated with single lateral mass fractures (Landells type III).</p><p><b>RESULTS</b>All patients were followed up for 6 to 24 months after operation (av- eraged 13 months), and all the patients had the clinical symptoms improved to some extent. Operation time ranged from 80 to 140 min (averaged 98 min); the intra-operative blood loss was 120 to 300 ml (averaged 180 ml); and the average fluoroscopic time was 55 s. No patients happened neurological and vertebral artery injuries-related complications or other complications after operation. The followed-up X-ray and CT manifested osseous fusion in all the 8 patients,no loosening or breakage of the screws.</p><p><b>CONCLUSION</b>Transoral plate internal fixation for instability atlas fracture is a reliable and safety technique that allows maintenance of rotatory mobility in the C1,2 joint and restoration of congruency in the atlanto-occipital and atlanto-axial joints.</p>

Anatomic study of lower cervical spinous process for laminar screw fixation / 中国骨伤

<p><b>OBJECTIVE</b>To measure anatomic data of spinous process and vertebral plate and evaluate the possibility of fixation of spinous process and vertebral plate.</p><p><b>METHODS</b>Twenty cadaveric cervibal spines of C3-C7 were dissected to expose vertebral plate and spinous process, and were measured by two methods, one was manual measured using digital caliper and the other was computed tomography scaning. Parameters were measured manually including vertebral plate height and width. The screw was inserted from the boundary of the vertebral plate and spinous process, and gone out from the top of vertebral plate back of opposite side. Then through the CT reconstruction, angle of screw insertion, length of screw trajectory and distance between the screw tip and vertebral artery and spinal cord were measured. Additionally, spinous process width and vertebral plate thickness of 100 patients' CT scans of C3-C7 cervical segment were measured to evaluate possibility of screw insertion at spinous process and vertebral plate.</p><p><b>RESULTS</b>The screw fixation of lower cervical spinous process and vertebral plate were successfully placed,without impingement of spinal cord and vertebral artery. There was no statistic difference on the data of lamina height and width of 20 cadaver specimens between manual and CT measurements (P>0.05). Height and width of vertebral plate was (12.4 +/- 1.2) to (13.7 +/- 1.3) mm and (4.5 +/- 0.9) to (5.4 +/- 1.1) mm respectively and increased gradually from C3 to C7 (P<0.05). The trajectory length was (13.7 +/- 1.2) to (15.8 +/- 1.8) mm and increased gradually from C3 to C7 (P<0.05). The distance between screw tip and vertebral artery and spinal cord was (20.1 +/- 2.7) to (25.8 +/- 2.9) mm and (4.1 +/- 1.8) to (5.0 +/- 1.2) mm respectively. The angles of screws insertion were (73.0 +/- 9.9) degrees to (85.3 +/- 10.1) degrees in the axial plane (P>0.05). Based on the CT measurements of 100 patients,the data of the spinous process width and lamina thickness varied from a minimum of (8.5 +/- 1.1) mm and (4.3 +/- 0.5) mm for the C4, to a maximum of (14.5 +/- 2.0) mm and (6.0 +/- 1.1) mm for the C7 respectively.</p><p><b>CONCLUSION</b>Lower cervical spinous process and vertebral plate screw fixation is feasible, which is a safe and stable screw approach for spinous process and vertebral plate fixation.</p>

Clinical application of lower cervical spinous process laminar screw technique in open door laminoplasty / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the clinical outcomes of lower cervical spinous process laminar screw technique in open door laminoplasty.</p><p><b>METHODS</b>From February 2005 to June 2010,12 patients with cervical myelopathy were treated with open door laminoplasty by lower cervical spinous process laminar screw technique. There was intervertebral disc herniation with degenerative stenosis in 5 patients, ossification of posterior longitudinal ligament with osteophyte in 6 patients, cervical traumatic instability with spinal cord injuries in 1 patient. Nerve function, complications, and the cervical canal to body ratio (CBR), range of motion (ROM) and the anteroposterior serial alignment were observed by Japanese Orthopedic Association (JOA) score, X-ray, CT and MRI.</p><p><b>RESULTS</b>The surgical time was from 1.5 to 2 h with an average of 110 min; blood loss during operation was from 450 to 800 ml with an average of 580 ml. Postoperative complication occurred in 1 case with upper limb pain and 1 case with cerebrospinal fluid leakage. All patients were followed up from 1 to 2 years with an average of 21.8 months. JOA score improved from preoperative 9.5 +/- 1.8 to postoperative 13.6 +/- 2.4 (P < 0.01). X-ray, CT, MRI showed CBR increased obviously (P < 0.01); ROM on flexion-extension and cervical lordosis decreased respectively from (40.0 +/- 10.0) degrees and (65.0 +/- 12.0)% before operation to (15.0 +/- 5.0) degrees and (42.0 +/- 8.0) % at the final follow-up (P < 0.01).</p><p><b>CONCLUSION</b>Lower cervical spinous process laminar screw technique in open door laminoplasty for cervical syndrome is safe and can obtain satisfactory effects, has strong internal fixation and reduce the risk of re-closure.</p>

Study on the feasibility of posterior thoracic transarticular screw fixation / 中国骨伤

<p><b>OBJECTIVE</b>To study the feasibility and technical parameters of posterior transarticular screw fixation in the thoracic spine.</p><p><b>METHODS</b>Since September 2009 to December 2009, 20 thoracic cadaveric spines (12 males and 8 females) were dissected. The lateral masses and pedicles were exposed carefully. After the entrance point of transarticular screws was determined, posterior transarticular screws implantation was performed under direct visualization into T(1,2), T(5,6) and T(9,10). Then CT scan was performed. On the CT scan,the angle and length of the transarticular screw trajectory were measured.</p><p><b>RESULTS</b>The thoracic transarticular screw trajectory were caudal tilting in the sagittal plane and lateral tilting in the coronal plane with successful placement. There was little differences between different segmental of thoracic vertebrae of the angle, but without significance (P > 0.5). The average angles of the screws were (52.6 +/- 5.9) degrees caudal tilting in the sagittal plane and (12.4 +/- 2.9)0 lateral tilting in the coronal plane. The average trajectory lengths were (22.5 +/- 1.9) mm. There was significant differences statistically among T(1,2), T(5,6) and T(9,10) (P < 0.01).</p><p><b>CONCLUSION</b>Posterior transarticular screw fixation is feasible. Transarticular screw fixation in the thoracic spine affords an alternative to standard pedicle screw placement for thoracic stabilization.</p>

Effect of exogenous adrenomedullin on renal and hypothalamus adrenomedullin expression in rats early after mechanical renal trauma / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of exogenous adrenomedullin (ADM) on endogenous expression of ADM in the kidney and hypothalamus of rats early after mechanical renal trauma.</p><p><b>METHODS</b>Adult Wistar rats were randomized into 4 groups (n=32), namely the control group, renal impact trauma group, preventive ADM injection group, and therapeutic ADM injection group. In the latter two groups, ADM (0.1 nmol/kg) was administrated by intraperitoneal injection 10 min before and 10 min after renal trauma. The rats were executed at 1, 6, 12, and 24 h after the trauma to examine the expression of ADM in the kidney and hypothalamus.</p><p><b>RESULTS</b>In preventive ADM injection group, the renal expression of ADM increased significantly at 1 h after the trauma (P<0.05) and tended to further increase with time till 24 h when its expression recovered the normal level. In the therapeutic ADM injection group, strong renal ADM positivity was found at 1 and 6 h after the injury (P<0.05) followed by gradual decrease till recovering the normal level at 24 h. Low renal ADM expression was detected, which was the strongest at 1 and 12 h (P<0.05) and became normal at 24 h. The time course of ADM expression in the hypothalamus was similar to that in the kidney in the therapeutic ADM injection group, and in the preventive injection group, the strongest ADM expression in the hypothalamus occurred at 6 and 24 h, and the lowest expression occurred at 12 h (P<0.05). The trauma group showed significantly decreased ADM expression in the hypothalamus compared with the control group (P<0.05).</p><p><b>CONCLUSION</b>The hypothalamic ADM expression can upregulate renal ADM expression. ADM maintains the relative stability of the internal environment and physiological activity by local and systemic positive and negative feedback mechanisms.</p>

Micro-endoscopic discectomy for the treatment of lumbar disc herniation in senile patients over seventy years old / 中国骨伤

<p><b>OBJECTIVE</b>To explore applicability and therapeutic effects of Micro-endoscopic discectomy (MED) for the treatment of lumbar disc herniation in senile patients over seventy years old.</p><p><b>METHODS</b>Thirty-two patients over seventy years old with lumber disc herniation were treated by MED from December 2007 to June 2010. Among them,20 patients were male and 12 patients were female,ranging in age from 70 to 86 years, with an average of 78.5 years old. The course of diseases ranged from 2 weeks to 30 years, with an average of 3.5 years. The main clinical symptoms were low back pain with radiating pain in lower extremities, especially under the keen joint. The surgical time, blood loss, complications and function recovery were evaluated retrospectively immediately after operation. X-ray at 1 week after operation was used to observe the change of physical curvature of lumbar; MRI at 1 month after operation was used to observe the radiographic change of lumbar before and after treatment; MacNab standard was applied to evaluate the therapeutic effects at 3 months after operation.</p><p><b>RESULTS</b>The mean follow up period was 12.5 months (from 3 to 30 months). The mean operative time was 60 min (from 30 to 120 min) and the mean blood loss was 45 ml (from 15 to 150 ml). Leakage of cerebrospinal fluid occurred in 1 case, the operation continued after pressing by brain cotton and without nerve root and vessels injury; 1 case aggravated after revive, but other patients were eased. X-ray at 1 week after operation showed physical curvature of lumbar of 25 patients improved; MRI at 1 month after operation showed residue intervertebral disc and calcification tissue in 8 cases. Eleven patients still had numbness of limbs,but the pain and tenderness of limbs relieved. According to MacNab standard at 3 months after operation, 25 cases got an excellent result (78.1%), 6 good (18.8%) and 1 fair (3.1%).</p><p><b>CONCLUSION</b>MED is effective for the senile patients over 70 years old with lumbar disc herniation and promotes ambulation earlier. MED has the advantage of minimal invasive, less blood loss and good clinical effects; MED is suitable for the patients with obvious radiating pain in lower extremities, especially under the keen joint and combine with mild spinal stenosis and root stenosis.</p>

Anatomic comparison between spinous process screws and pedicle screws techniques of the second cervical vertebar / 中国骨伤

<p><b>OBJECTIVE</b>To compare anatomic difference between spinous process screws and pedicle screws techniques of the second cervical vertebra.</p><p><b>METHODS</b>Ten human cadaveric of cervical spine (5 male, 5 female) were harvested and had no gross deformities such as scoliosis and/or kyphosis were found in the study. The average age of the subjects was 60.5 years. The specimens were placed in the prone position. Posterior cervical exposure was attained by dissecting all soft tissue off the posterior aspect of the second cervical vertebra. After clear exposure of the lateral mass,the spinous process screw and pedicle screw insertion techniques were performed in this study. Each technique involved ten specimens and 10 screws inserted into C2 bilaterally. The one side of C2 was randomly selected for the spinous process screw and the other side was designate for the pedicle screw. This point then was drilled with a 3 mm drill, and followed by placement of a 4.0 mm cortical screw. The starting point for spinous process screw insertion was located at the junction of the lamina and the spinous process and the direction of the screw was about 0 degrees caudally in the sagittal plane and about O0 medially in the axial plane. The starting point of pedicle screw should be the midpoint of the base of inferior articular facet of the axis. The drilling angle was 15 degrees to 20 degrees in the superior direction and 30 degrees in the medial direction. After screw placement, all the specimens were CT scaned. On the CT scan,the length of the spinous process screw and pedicle screw trajectory were measured. Results were recorded for each screw that violated impinged of the pedicle, spinal canal and transverse process foramen.</p><p><b>RESULTS</b>All the C2 spinous process screws were successfully placed, without impingement the spinal cord, the vertebral artery and the breakage of the spinous process. There was one pedicle screw breaking the pedicle into the vertebral artery foramen. The trajectory length for the spinous process screws were (21.4 +/- 1.4) mm,compared with the pedicle screws (23.7 +/- 1.0) mm. But there was no significant differences between spinous process screws and pedicle screws techniques (t = -4.387, P > 0.05).</p><p><b>CONCLUSION</b>The C2 spinous process screw fixation has the anatomic feasibility and is easier to perform than pedicle screw fixation.</p>

An anatomic study of posterior C(2) spinous process laminar screw fixation / 中华外科杂志

<p><b>OBJECTIVES</b>To explore the feasibility and the technical parameters in posterior C2 spinous process laminar screw fixation, and discuss the clinic significance of C2 spinous process laminar screws.</p><p><b>METHODS</b>Twenty cervical cadaveric spines of C2 were dissected, with care taken to expose the lamina and spinous process. After the entrance point of spinous process screw were determined, posterior C2 spinous process laminar screw implantation was performed under visual control. On the morphologic CT scan, the angle and length of the spinous process laminar screw trajectory and the distance between the tip of the screw and the spinal cord and the vertebral artery were measured.</p><p><b>RESULTS</b>The C2 spinous process laminar screws were successfully placed, without impingement of the spinal cord and the vertebral artery. There were little differences between superior and inferior screws in the angle, trajectory length and the distance between the tip of the screw and the spinal cord and the vertebral artery, but without significance (P > 0.05). The placed angles of the screws were 76.8° ± 10.6° in the axial plane. The distance between the tip of the screw and the spinal cord and the vertebral artery was (5.3 ± 1.6) mm and (17.4 ± 3.7) mm respectively. The trajectory length was (23.1 ± 3.2) mm.</p><p><b>CONCLUSIONS</b>Posterior C2 spinous process laminar screw fixation is feasible. C2 spinous process laminar screw fixation affords an alternative to standard screw placement for plate fixation and cervical stabilization.</p>

Biomechanical study on transarticular screw and plate fixation syetem in the lower cervical spine / 中国骨伤

<p><b>OBJECTIVE</b>To compare the cervical stabilities of transarticular screw fixation alone, and transarticular screw and plate fixation system.</p><p><b>METHODS</b>Twelve specimens of cervical vertebra containing C2-T1 were obtained from human cadaver. The three-column instability model was made at C4.5 and C5.6 levels. The specimens were stabilized with transarticular screw fixation alone, and transarticular screw and plate fixation system respectively. The ranges of motion of segments including intact group, transarticular screw fixation alone group and transarticular screw and plate fixation system group were measured under the torque of 2.0 N x m in flexion, extension, lateral bending, and torsion respectively under nonrestrictive and nondestructive condition.</p><p><b>RESULTS</b>The rang of motion (ROM) and neutral zone (NZ) of both transarticular screw fixation alone and transarticular screw and plate fixation system group were significantly smaller than those of intact group in all directions (P < 0.05). The transarticular screw and plate fixation system group allowed a very smaller ROM and NZ than transarticular screw fixation alone during extension, lateral bending and axial rotation except flexion (P < 0.05).</p><p><b>CONCLUSION</b>Cervical transarticular screw and plate fixation system provides better stability than transarticular screw fixation alone. If the transarticular fixation technique is preferred, transarticular screw and plate fixation system will be beneficial.</p>

Clinical observation of mid-stage complications after cervical disc replacement / 中国骨伤

<p><b>OBJECTIVE</b>To summarize the therapeutic experience of Bryan prosthetic cervical disc replacement at the 3rd years after operation and to analyze the clinical effect, incidence rate of heterotopic ossification, conditions of prosthetic fusion in order to investigate the countermeasures.</p><p><b>METHODS</b>From December 2005 to December 2008, 54 patients with cervical syndrome (34 males and 20 females, the age was from 39 to 69 years with an average of 50.5) were treated with single level Bryan prosthetic cervical disc replacement. The patients were followed for 24-36 months with an average of 30 months. The symptoms and nerve function were evaluated according to JOA and Odom's scoring. The anterior-posterior and lateral cervical X-ray films were also taken regularly every three months for the observation of heterotopic ossification and prosthetic fusion. Meanwhile, the X-ray films of the forward bending, extending, left and right lateriflection were taken before operation and at the 1st years after operation for the measurement of the stability and rang (ROM) of replaced levels.</p><p><b>RESULTS</b>The pain symptom and neurological function of all 54 patients were improved obviously. JOA score increased with an average of 76.1%, and ROM of replaced levels also improved obviously. The incidence rate of heterotopic ossification and prosthetic fusion went up year by year, 3.7% (2/54) for the first year, 16.7% (9/54) for the second year and 22.2% (12/54) for the nearly third year.</p><p><b>CONCLUSION</b>Bryan prosthetic cervical disc replacement has better mid-stage results than conventional methods. Modified surgical methods and early rehabilitation exercise may reduce the relatively high incidence rate of heterotopic ossification and prosthetic fusion.</p>

Anatomical considerations for the placement of C₂ spinous process screws / 中华外科杂志

<p><b>OBJECTIVES</b>To quantitatively anatomically evaluate the C₂ spinous process, analyze the anatomical feasibility of the C₂ spinous process screws and its clinical significance.</p><p><b>METHODS</b>To dissect and evaluate 30 cervical cadaveric spines of C₂ which were taken to expose the lamina and spinous process. Anatomic quantitative evaluation of the C₂ spinous process included its height and width. Twenty cervical cadaveric spines of C₂ were chosen to the study of the placement of the C₂ spinous process screws. The starting point for the C₂ spinous process screw insertion was located at the base of the spinous process. After the entrance point of spinous process screws was determined, posterior C₂ spinous process screw implantation was performed bilaterally under direct visualization. On the morphologic CT scan, the width of C₂ spinous process base, the angle and length of the spinous process screw trajectory, and the distance between the tip of the screw and the spinal cord and the vertebral artery were measured.</p><p><b>RESULTS</b>The average height and width of the C₂ spinous process were (12.90 ± 1.30) mm and (18.86 ± 1.17) mm respectively. The C₂ spinous process screws were successfully placed without impingement the spinal cord or the vertebral artery and the breakage of the spinous process. On the CT scan, the average width of the base of C₂ spinous process was (20.7 ± 1.3) mm. The placed angles of the screws were 1.8° ± 1.0° in the axial plane. The distance between the tip of the screw and the spinal cord or the vertebral artery was (8.3 ± 2.6) mm and (20.2 ± 3.1) mm respectively. There were little differences between superior and inferior screws in the angle, the distance between the tip of the screw and the spinal cord or the vertebral artery, but without significance (P > 0.05). The average trajectory length of the C₂ spinous process screws was (19.7 ± 1.1) mm. The average trajectory length of the superior spinous process screws was shorter than that of inferior spinous process screws, with great differences (t = 3.566, P < 0.01).</p><p><b>CONCLUSIONS</b>There is the anatomic feasibility of the C₂ spinous process screw fixation which may afford an alternative to standard screw placement for axis fixation. The biomechanical study for the C₂ spinous process screw is also necessary.</p>

Application of the pedicle screws for cervicothoracic fracture-dislocation / 中国骨伤

<p><b>OBJECTIVE</b>To explore pedicle screw implantation for fracture-dislocation injuries at cervicothoracic junction (C6-T2).</p><p><b>METHODS</b>Pedicle screw implantation was used for twenty-six patients with cervicothoracic fracture-dislocation from May 2001 to Jan 2008. There were 17 males and 9 females with an average of 48.5 years (range,20 to 75 years). Single posterior pedicle screw fixation was performed for 17 cases, and posterior screw fixation combined with anterior reduction and plate fixation for the other nine. The accuracy of the pedicle screws were evaluated by CT views after surgery. Complications and neurological recovery were also recorded after the procedures.</p><p><b>RESULTS</b>All subjects were followed up from 3 to 74 months with average 36.5 months. Four cases of complete paraplegia died of cardiovascular or pulmonary failure within half a year after surgery. There were 104 pedicle screws implanted totallythe including 74 pedicle screws in cervical vertebrae, 16 at C5, 16 at C6, 42 at C7, and 30 pedicle screws in upper thoracic vertebrae,in which 22 at T1, 8 at T2. No injury of spinal cord, nerve roots and vertebral artery was found during operation. Eleven screws (14.9%) were perforated out of the pedicles in cervical spine, in which 7(9.5%) through lateral cortex, 1 (1.4%) through the superior and 3 (4.1%) through the inferior. Three screws (10%) were perforated in upper thoracic spine, in which 2 (6.7%) by lateral cortex and 1(3.3%) by the medial (within 2 mm). Bony fusion was achieved for all cases and all internal fixator was good except 1 screw broken at C5. JOA score increased from preoperative (7.5 +/- 2.0) to postoperative (14.5 +/- 2.3) evaluated in 6 months after operation,with statistic difference (t = 6.34, P < 0.05). Neurological improvement was gotten in all patients according to ASIA classification but three cases who suffered from complete neurological injuries.</p><p><b>CONCLUSION</b>Implantation of pedicle screws at cervicothoracic junction can be safe and reliable if the urgeonis familiar with the local anatomy of cervicothoracic spine, and the technique for implantation of the screws. Related radiological parameters should be measured for each subject before the operation in attempt to get a therapy individually.</p>

Experimentation and investigation of the effects of TNF and the acceptor expression in renal early trauma with extraneous adrenomedullin / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of TNF-alpha, TNF-beta and the acceptor expression about mechanical renal trauma with extraneous ADM.</p><p><b>METHODS</b>There were 104 healthy adult plain grade Wistar rat, randomly divided into four groups:8 in the group of control, 32 in the group of trauma, 32 in the group injected ADM before trauma, 32 in the group injected ADM post trauma. The experimental model of rat kidney with mechanical trauma was prepared by striking the area of rat skin reflecting by kidney with free dropping ferrous hammer in the last three groups. ADM (0.1 nmol/kg) administrated by intraperitoneal injection at 10 minutes before trauma or post trauma respectively in injected groups. All rats were executed by drawing-out all the blood in their hearts. Renal tissue was investigated to study positive expression of TNF-alpha, TNF-beta, TNFR after SABC stained.</p><p><b>RESULTS</b>TNF-alpha expression:the TNF-alpha expression of trauma group was more positive than it of control group in the wound early time. The expression of group injected post trauma was less than it of trauma group at 1 h (P < 0.01). The expression of group injected before trauma was less than it of trauma group at 6 h (P < 0.05) TNF-beta expression: the TNF-beta expression of trauma group was less than it of control group at 1 h and 6 h (P < 0.05). The TNF-beta expression of group injected post trauma was more positive than it of trauma group at the same time of 1 h and 6 h (P < 0.01). TNFR expression: the TNFR expression of trauma group was less than it of control group at 6 h (P < 0.01). The TNFR expression of group injected before trauma was more positive than it of trauma group in the at the same time of 1 h and 6 h (P < 0.01).</p><p><b>CONCLUSIONS</b>The TNFR can regulate the TNF-alpha and the TNF-beta in dynamic balancing. The regulation of TNFR is main to TNF-alpha. What the TNF-beta participated in renal trauma mainly is the anti-damage process. ADM can reduce the expression of TNF-alpha. ADM increases the expression of TNF-beta and TNFR.</p>

Selective treatment of thoracolumbar fracture with posterior monosegmental pedicle screw fixation / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical effects of posterior monosegmental pedicle screw fixation in selective treatment of thoracolumbar vertebral fractures.</p><p><b>METHODS</b>From June 2005 to June 2008, 28 patients (male 17 and female 11, the age was 19- 60-years-old with an average of 36 years) with thoracolumbar fractures were treated with posterior monosegmental pedicle screw fixation in our department. According to the AO classification, 19 patients with type A1 fracture and 9 with type A2. The place of pedicle screw and reduction of injured vertebral body were observed.</p><p><b>RESULTS</b>Postoperative CT scan showed 56 pedicle screws were all placed in the normal part of injured vertebral body. There was no spinal cord injury and infection after surgery. There were restoration of anterior body compression from mean preoperative (42.0 +/- 5.6)% to (12.4 +/- 1.4)% (P<0.05), and restoration of Cobb angle from mean preoperative (25.8 +/- 5.1) degrees to postoperative (1.9 +/- 1.3) degrees (P<0.05). All the patients were followed up for 3-36 months (average in 18.3 months). All fractures achieved bone healing, without significant loss of the vertebrae body height and implant failure.</p><p><b>CONCLUSION</b>As indication is correctly choosed, posterior monosegmental pedicle screw fixation can be applied to treat thoracolumbar vertebral fractures.</p>

Biomechanical comparison of cervical transfacet pedicle screws versus pedicle screws / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Transfacet pedicle screws provide another alternative for standard pedicle screw placement for plate fixation in the lumbar spine. However, few studies looking at transfacet pedicle screw fixation in the cervical spine are available. Therefore, cervical transfacet pedicle screw fixation and standard pedicle screw fixation techniques were biomechanically compared in this study.</p><p><b>METHODS</b>Ten fresh human cadaveric cervical spines were harvested. On one side, transfacet pedicle screws were placed at the C3-4, C5-6, and C7-T1 levels. On the other side, pedicle screws were placed at the C3, C5, and C7 levels. The screw insertion technique at each level was randomized for right or left. The starting point for the transfacet pedicle screw insertion was located at the midpoint of the inferolateral quadrant of the lateral mass and the direction of the screw was about 50 degrees caudally in the sagittal plane and about 45 degrees toward the midline in the axial plane. Screws were placed from the inferior articular process, across the facet complex and the pedicle into the body of the caudal vertebra. The entry point for the pedicle screw was located at the midpoint of the superolateral quadrant of the lateral mass, and the direction of the screw was about 45 degrees toward the midline in the axial plane and toward the upper third of the vertebral body in the sagittal plane. After screw placement we performed axial pullout testing.</p><p><b>RESULTS</b>All the cervical transfacet pedicle screws and the pedicle screws were inserted successfully. The mean pullout strength for the transfacet pedicle screws was 694 N, while for the pedicle screws 670 N (P=0.013). In all but six instances (10%), the pedicle screw pullout values exceeded the values for the transfacet pedicle screws; this occurred three times at the C3/C4 level, twice at the C5/C6 level and once at the C7/T1 level. The greatest pullout strength difference at a single level was observed at the C5/C6 level, with a mean difference of 38 N (t=-1.557, P=0.154). The C7/T1 level had a mean difference of 26 N and the C3/C4 level had a mean difference of 14 N.</p><p><b>CONCLUSIONS</b>Cervical transfacet pedicle screws exhibited higher pullout strength than pedicle screws. Posterior transfacet pedicle screw fixation in the cervical spine may afford an alternative to standard screw placement for plate fixation and cervical stabilization.</p>

Analysis of complications in scoliosis surgery / 中国骨伤

<p><b>OBJECTIVE</b>To analyze the complications occurred in scoliosis surgery and evaluate its prevention strategy.</p><p><b>METHODS</b>From June 2002 to May 2007, 86 cases of idiopathic scoliosis were treated. There were 21 male and 65 female with an average age of 17.8 years(range, from 8 to 22 years). According to Lenke classification, 33 cases were type 1, 10 type 2, 18 type 3, 5 type 4, 10 type 5 and 10 type 6. Five cases were Risser 0 to I, 20 cases II to III, 61 cases 1V to V. Cobb angles were from 45 degrees to 85 degrees (mean 60.35 degrees). The pedicle screw technique was used to correct all the scoliasis, and the results and complications were studied.</p><p><b>RESULTS</b>The average operation time was 3.2 hours and average blood loss volume was 1000 ml (800-2400 ml), 924 pedicle screws were inserted and the average postoperative Cobb angle was 18.46 degrees. All the patients were followed up for 5 to 40 months(mean 20.5 months). The complications were as following: 1 case of spinal cord injury; 25 screws misplaced; 2 cases of nerve root injury; 1 case of pleura injury; 1 case of superior mesenteric artery syndrome; 3 cases of wound infection; 2 cases of trunk decompensation; 1 case of junction kyphosis; 3 cases of implant loosening; 2 cases of pseudarthrosis; 1 case of crankshaft phenomenon; 2 cases of flatback syndrome.</p><p><b>CONCLUSION</b>Many kinds of complications may occur in scoliosis surgery. Exactitude procedures of diagnosis and surgery for the scoliosis are the key to decrease and prevent the complications related to the operation.</p>

All pedicle screws technique applied to the treatment of idiopathic scoliosis / 中国骨伤

<p><b>OBJECTIVE</b>To Analyze the therapeutic efficacy of all pedicle screws technique applied to the treatment of idiopathic scoliosis and evaluate its safety.</p><p><b>METHODS</b>From June 2002 to October 2005, 56 patients with idiopathic scoliosis were treated with all pedicle screws technique, including 11 males and 45 females, ranging in age from 8 to 22 years. According to Lenke classification, 29 patients were Type 1, 6 patients were Type 2, 8 patients were Type 3, 2 patients were Type 4, 8 patients were Type 5, and 3 patients were Type 6. Cobb angles ranged from 45 degrees to 85 degrees (mean 62.45 degrees).</p><p><b>RESULTS</b>The mean operation time was 3 hours and 20 minutes, and the average amount of bleeding was 600 ml. There were 425 pedicle screws inserted including 244 in thoracic, and 181 in lumbar, the positions of which were evaluated by CT. Nine screws were inserted with perforating through the medial wall of the pedicles. All the patients were followed up for 5 to 40 months (mean 22.5 months). The mean Cobb angle was corrected from 62 degrees preoperatively to 18 degrees postoperatively,and the average correction rate was 72.5%. No spinal nerves injury was found after operation, and superficial infection occurred in 2 patients but recovered after dressing change. All the patients got satisfactory spinal fusion and remained partly spinal mobility with fewer complications.</p><p><b>CONCLUSION</b>The application of all pedicles screws technique with familar with pedicular anatomy of scoliosis by imaging examination could gain a satisfactory effect of correction with less complications.</p>