The Sagittal Alignment of Spine in Conservatively Treated Osteoporotic Compression Fractures of Thoracolumbar Junction / 대한골다공증학회지

OBJECTIVES: To evaluate the radiological outcomes of conservative treatment for osteoporotic compression fractures in thoracolumbar junction. MATERIALS AND METHODS: 20 osteoporotic compression fracture cases of thoracolumbar junction (group I) which were treated conservatively using TLSO brace were evaluated compared with 20 osteoporotic spine cases (group II), between August 2010 and March 2012. The mean age was 65.3, ranging from 57 to 71 years old. The average follow up period was 27.4, ranging from 17 to 35 months. The bone marrow density (BMD) was recorded at the initial assessment. The lumbar lordotic angles with compression ratios on the initial and the last follow-up plain lateral radiograph were measured, and the sagittal alignments of spine were evaluated. RESULTS: In group I, the average compression ratios initially and at the last follow up were 23.5% and 33.7% respectively, and the average lumbar lordotic angles initially and at the last follow up were 30.8degrees and 22.6degrees respectively. In group II, the average lumbar lordotic angles initially and at the last follow up were 40.3degrees and 39.9degrees respectively. In group I, the compression ratio was significantly increased, and the lumbar lordotic angle was decreased at the final follow up. In group II, the difference of lumbar lordotic angles was not significant statistically. CONCLUSIONS: In most, the osteoporotic compression fractures can be successfully managed conservatively. But, in some cases of thoracolumbar junction, the further collapse of vertebral body and the change of lumbar lordotic angle can be developed, and then sagittal alignment of spine can be disrupted.

Comparison of Clinical Results according to the Complications after or during Open Door Laminoplasty Surgery for Cervical Myelopathy / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to compare and analyze the clinical results according to the complications occurring after laminoplasty for cervical myelopathy patients. MATERIALS AND METHODS: Among patients diagnosed as cervical myelopathy, 152 cases in which patients underwent cervical laminoplasty from March 2006 to March 2011 from Chungnam National University Hospital and had follow-up for at least two years were selected for the study, and the mean follow-up period was 39.7 months. The cases were divided into two groups; cases that underwent plate fixation for hinge fracture during cervical laminoplasty or showed postoperative spontaneous interlamina fusion were included in group A and cases that did not show such complications were included in group B. Clinical results were measured using visual analogue scale (VAS) score and Neck Disability Index (NDI) preoperatively, postoperatively, and on the final follow-up. RESULTS: Among 152 cases, 31 cases were included in group A and 121 cases in group B. Group A consisted of 11 cases of fixation due to intraoperative hinge fracture and 20 cases of postoperative spontaneous interlamina fusion. Mean preoperative VAS score was 7.52 in group A and 7.26 in group B, and mean postoperative VAS score was 2.87 in group A and 3.03 in group B. Mean NDI improved from 74.32% preoperatively to 43.84% postoperatively in group A and 75.74% preoperatively to 45.36% postoperatively in group B. In both groups, on postoperative follow-up, no significant difference of VAS score and NDI was found and both showed improvement compared to before surgery. CONCLUSION: The clinical results of cases that underwent plate fixation for hinge fracture that occurred during cervical laminoplasty and postoperative spontaneous interlamina fusion showed no significant difference compared to cases that did not show any complications.

Operative Risk Assessment of Degenerative Spinal Disorder Comparing with Total Hip Replacement

STUDY DESIGN: Retrospective study. OBJECTIVES: To assess the operative risks and complications of posterior decompression and fusion for degenerative spine disorders, we compared single level posterior decompression and posterolateral fusion of lumbar spine with total hip arthroplasty which have been evaluated in many reports and articles on complications and operative risks. SUMMARY OF LITERATURE REVIEW: There has been no study comparing the relative risks of spinal surgery with total hip arthroplasty. MATERIALS AND METHODS: One hundred and thirty-six subjects (mean age 69.6 years) who received single level posterior decompression and posterolateral fusion for degenerative lumbar disorders from February 2000 to May 2010 were selected as group A, and 136 subjects (mean age 67.2 years) who received total hip arthroplasty during the same period were selected as group B. A comparative analysis was performed according to age, gender, pre-operative ASA status based on their underlying medical conditions, total operative time, blood loss, hospitalization period, incidence of major and minor complications and functional recovery at the time of final follow up using retrospective and statistical manners from medical records and radiologic evaluations. RESULTS: The total operative time and blood loss were longer in group A with statistical significance (P<0.01). Major complications were frequent in group B with 16 cases and in group A with 6 cases (P<0.05). There were no significant differences in the total hospitalization period, incidence of minor complications and post-operative functional recovery. CONCLUSIONS: The present study revealed no increased operative risks for surgery for degenerative lumbar disorders compared with total hip arthroplasty in similar age groups.

Correlation of Adjacent Segmental Disease with Tilt Angles of the Upper and Lower Instrumented Vertebra in the Degenerative Lumbar Scoliosis

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the correlation of adjacent segmental disease with tilt angles of the upper and lower instrumented vertebra after instrumented posterolateral fusion for degenerative lumbar scoliosis. SUMMARY OF LITERATURE REVIEW: There has been no study of radiologic measurement and decision of fusion level using the angle of pedicle screws inserted for treatment of degenerative lumbar scoliosis. MATERIALS AND METHODS: From 2004 to 2008, 74 patients that underwent decompression and posterolateral fusion for degenerative lumbar scoliosis were included in this study. In all cases, instrumentation and posterolateral fusion were both performed. The sex ratio was 31:43, the mean age was 68.7 years and the mean follow up duration was 37.4 months. The angle between each upper end plate of the upper vertebral body and lower end plate of the lower vertebral body of the fusion, and the line parallel to the axis of the sagittal line of vertebrae was each defined as UIV-a and LIV-b. The correlation of development of adjacent segment disease and UIV-a, and LIV-b angle was investigated. RESULTS: Sum of the absolute value of UIV-a and LIV-b had a statistically significant positive correlation with that of adjacent segment disease. Also, UIV-a alone, had a statistically positive correlation with the development of proximal adjacent segment disease. CONCLUSIONS: Since it is proven that adjacent segment disease has positive correlation with the sum of the absolute value of UIV-a and LIV-b, the extent of fusion should be adjusted to make the line parallel to the line perpendicular to the sagittal surface.

Changes in Cervical Spine Range of Motion after Laminoplasty in Cervical Spondylotic Myelopathy

STUDY DESIGN: A retrospective study. OBJECTIVES: This study examined the cervical range of motion (ROM) of cervical spondylotic myelopathy patients, before and after open door laminoplasty. SUMMARY OF LITERATURE REVIEW: Majority of the cases regarding the change of cervical range of motion after cervical laminoplasty showed decreased range of motion, and the results were diverse. MATERIALS AND METHODS: Of the 487 patients, who underwent open door laminoplasty at our hospital from March 1997 to March 2008, 98 had been followed for at least 2 years and had cervical flexion-extension lateral x-rays. In all patients, open door laminoplasty involved at least three segments: three, four, and five segments in 11, 52, and 35 patients, respectively. In previous cases, fixation involved sutures using suture anchors. The lordosis or kyphosis between C2 and C7 was analyzed using cervical flexion-extension lateral radiographs before and 2 years after the operation. RESULTS: The average patient age was 62.7 (range 32-82) years; 65 patients were male and 33 were female. From preoperatively to postoperatively, the average kyphosis of cervical flexion decreased from 10.7degrees to 7.8degrees, average lordosis decreased from 21.2degrees to 14.2degrees, and cervical ROM decreased from 31.9degrees to 22.0degrees, respectively (mean 9.9degrees, 31.0%). CONCLUSIONS: We could observe decreased cervical range of motion after cervical laminoplasty for cervical spondylotic myelopathic patients. Thus, the treatment to prevent the postoperative decrease of cervical range of motion and further study to find a new treatment are thought to be essential.

Differentiation of Osteoporotic Fracture from Metastatic Fracture in Spine using MRI / 대한골다공증학회지

OBJECTIVES: To determine that compression fracture of L5 and posterior convexity of the vertebral body on MRI are useful indicators of spinal metastasis. MATERIALS AND METHODS: Forty seven cases of vertebral compression fractures with magnetic resonance imaging (MRI) were reviewed. They were classified into two groups: the metastatic fracture (MF) group (n=23) and the osteoporotic fracture (OF) group (n=24). Each cases were evaluated according to their MRI findings of fracture site location, and the presence of posterior convexity of the vertebral body, intact midseptum and anterior signal change. Conventional T1 and T2 weighted images were obtained. Statistical analysis was done using the paired t-test and fisher's exact test. RESULTS: The MF group had 100% incidence of fracture in L5 (P<0.01). The incidence of positive posterior convexity was also 100%. The incidence of a positive anterior signal change was 67% (n=16) and intact septum was seen in 16 patients (67%). In the OF group, there were no fractures in L5 (16 cases with L1 fractures [67%]) and only 3 cases with posterior convexity (12.5%). Midseptum was intact in 19 cases (79%) and 6 patients with positive anterior signal change (25%). CONCLUSIONS: The location of vertebral fracture, especially in L5 and convex deformity of posterior vertebral body are reliable indicators of spinal metastasis.

The Relationship between the Pedicle Screw Loosening and Bone Mineral Density after Transpedicular Spinal Instrumentation / 대한골다공증학회지

OBJECTIVES: We have analyzed relationship between pedicle screw loosening and bone mineral densitiy (BMD) after spinal arthrodesis with pedicle screw. MATERIALS AND METHODS: We have chosen 31 cases that had screw loosening radiologically on the follow up X-ray among the patients who underwent spinal arthrodesis with pedicle screws, and compared Saville's index that was measured by lateral view of preoperative X-ray with Dual energy X-ray absortiometry (DEXA) score.

Variations of Neurotrophic Factors and It's Importances in Spinal Cord Injured Rats and Beagle Dogs

STUDY DESIGN: Experimental, prospective study OBJECTIVES: To examine the changes in the variable factors after an acute spinal cord injury(SCI) in rats and dogs simultaneously. SUMMARY OF LITERATURE REVIEW: No study has examined the variations of several factors in a SCI model in different species. MATERIALS AND METHODS: In rats, a laminectomy was performed at the T10 level and the injured spinal cord was extracted. In Beagle dogs, the laminectomy level was T10 and T11. The motor function was evaluated using a modified Tarlov's scale. A RT2 profiler PCR array was used to examine each factor (inflammatory cytokines, factors-related with apoptosis, neurotrophic factors, factors-related with extraceullar matrix). RESULTS: IL-2, TNF, TNFRSF11B increased with time and showed no statistical difference between two species, but TNFSF13B showed a significant difference. BDNF decreased with time in both species, and GDNF was significantly lower in dogs. NGFbeta, CTNF and its receptors showed no significant changes in the two species. MMP1 increased in both species but MMP7 decreased in rats and increased in dogs with time, and showed a significant difference between species. CONCLUSION: The change in inflammatory cytokines and extracellular matrix correlates with each factor in the combined patterns. Moreover, during the first week after SCI, inflammatory cytokines, apoptosis, neutrophic factors, and extracellular matrix factors may show a partial difference between experimental animals, which means that an animal model can be selected according to the particular experimental plan.

Comparative Study of Clinical Outcomes of Anterior Cervical Discectomy and Fusion Using Autobone Graft or Cage with Bone Substitute

STUDY DESIGN: A retrospective study. PURPOSE: To compare the clinical and radiological outcomes of autogenous bone graft and cage with bone substitute for anterior cervical discectomy and fusion. OVERVIEW OF LITERATURE: The clinical outcomes of cage with bone substitute for anterior cervical discectomy and fusion is satisfactory. METHODS: Eighty four patients who underwent cervical spine surgery between February 2004 and April 2009 were included. Fifty-nine patients were approached anteriorly and underwent anterior cervical discectomy and fusion by the Smith-Robinson method (Group A), and 25 patients underwent fusion by decompression of the cervical spine and cage with bone substitute (Group B). We measured and evaluated the postoperative period until patients were able to ambulate, for pre- and postoperative symptomatic improvement, postoperative complications, pre- and postoperative change of lordosis, degree of endplate collapse or subsidence, and fusion rate and period of union. RESULTS: By Robinson's criteria, respectively 45, 10 and 4 patients in Group A experienced excellent, good and fair symptomatic improvement, and respectively 19, 5 and 1 patients in Group B experienced excellent, good and fair symptomatic improvement. The postoperative period in which patients became ambulant and the period of hospital stay was significantly shorter in Group B. Increase of lordosis at final follow up after surgery was significantly larger in Group A, as was the fusion period. Significantly more endplate collapse occurred in Group B. CONCLUSIONS: Of patients who had anterior cervical discectomy and fusion, results of both groups were both satisfactory.

Psoas Abscess Caused by Spontaneous Rupture of Colon Cancer

Spontaneous rupture of colon cancer, combined with psoas abscess formation, is rare. A 44-year-old male visited for back pain and left buttock mass. Abdominal computed tomography and magnetic resonance image revealed a large abscess in the left psoas muscle and in the left lower quadrant area. Ten days after incision and drainage, a skin defect around the left anterior superior iliac spine remained. A local flap was performed using a superficial skin graft. Ten days after the stitches had been removed, fecal discharge was observed around the anterior superior iliac spine at the flap site. An operation was performed by a general surgeon who had diagnosed this as a case of enterocutaneous fistula. Operative findings included a ruptured tumor mass in the descending colon, which was connected to a retroperitoneal abscess. Pathologic report findings determined adenocarcinoma of the resected colon. Herein, we report a case of psoas abscess resulting from perforating colon cancer.

Clinical Outcome Based Cauda Equina Syndrome Scoring System for Prediction of Prognosis

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We made a scoring system using the symptoms of cauda equina syndrome(CES) and we studied the efficacy of the scoring system. SUMMARY OF THE LITERATURE REVIEW: There has been no definite scoring system with clear factors that can predict the clinical results of cauda equine syndrome. MATERIALS AND METHODS: Between 1998 and 2006, 21 patients who were diagnosed with CES and who were followed for more than 2 years were enrolled in this study. There were 6 cases of HIVD, 6 cases of degenerative spondylosis, 7 cases of vertebral fracture and 2 cases of metastatic spinal tumor. We made a scoring system for CES (SSCES) using 8 symptoms among the general clinical manifestations that accompany CES, which are low back pain, sciatic neuropathy, sensory and motor disorder of the lower extremities, loss of a saddle sensation, voiding difficulty, disorder of the anal sphincter tone and deep tendon reflex disorder. RESULTS: The last clinical outcomes were 3 excellent patients, 5 good patients, 5 fair patients and 8 poor patients. The mean preoperative SSCES was 11.7+/-2.8(7-16) and the mean final follow up score was 7.6+/-3.4(2-13). Eight cases that had a mean preoperative SSCES score of 6 or below showed good clinical results with a mean SSCES of 3.9+/-11(2-5) on the final follow up, and 13 cases with a mean preoperative SSCES score of 7 or above showed bad clinical results with a mean SSCES of 9.9+/-1.9(7-13) on the final follow up. CONCLUSIONS: The prognosis was better on the final follow up for the patients with a lowere preoperative SSCES. So, for the treatment of CES, preoperative evaluation using the SSCES is thought to be very useful for predicting the prognosis.

Clinical Results of Unilateral Partial Vertebroplasty(UPVP) in Osteoporotic Vertebral Fracture

STUDY DESIGN: This is a prospective clinical study. OBJECTIVES: We wanted to compare the clinical results of conventional vertebroplasty(VP) and the newly devised unilateral partial vertebroplasty(UPVP). SUMMARY OF LITERATURE REVIEW: There has not been any study on how to reduce the amount of cement used while maintaining the height of the vertebral body and minimizing the adjacent compression fractures. MATERIALS AND METHODS: From 2004 to 2008, Group 1 underwent VP and group 2 underwent UPVP. We compared the difference of the VAS score, the period of hospitalization, the infused amount of cement, the progression of the vertebral body collapse and fresh fracture of the adjacent vertebral body on the follow-up simple radiographs. RESULTS: In group 1, the mean VAS score changed from 6.69 to 2.80, the mean period of hospitalization was 2.30 days and the mean amount of cement infused was 6.50cc. The degree of vertebral body collapse was 0.83, 0.76, 0.69 and 0.63 on follow-up, and 3 cases had fresh fracture. In group 2, the mean VAS score changed from 6.41 to 2.61, the mean period of hospitalization was 2.23 days and the mean amount of cement infused was 3.74cc. The degree of collapse was 0.71, 0.69, 0.68 and 0.63 on follow up and 1 case had fresh fracture. The two groups showed no statistical significance for the change of the VAS score and the period of hospitalization, and the amount of cement was significantly less in group 2. The degree of collapse was not significantly different on the 4 times of follow-up. The frequency of fresh fracture was significantly less in group 2. CONCLUSIONS: UPVP could achieve similar results for pain relief, the period of hospitalization and vertebral body collapse as compared to that of VP, but fresh fracture of the adjacent vertebral body was less. So, UPVP could be a better method than VP.

The Differentiation of Phase of Spinal Cord Injury Based on the Changes in Gene Expression

STUDY DESIGN: An experimental study. OBJECTIVES: To define the phases of chronic spinal cord injury by researching the changes in gene expression. SUMMARY OF LITERATURE REVIEW: The exact time of conversion from acute stage to chronic stage in spinal cord injury is unknown. MATERIALS AND METHODS: We used 18 month-old Beagle dogs as study subjects. Under spinal cord monitoring, we underwent laminectomy on thoracic vertebra 10 and 11, and induced cord injury by a weight-drop injury method. Dogs in each group with spinal cord injury and group without spinal cord injury on POD 1, 7, 30, and 90. The motor functions were evaluated using the Tarlov scale. Tissues were prepared from 0.5cm up and down from the 10th thoracic level. Additional cephalic and caudal lesions from the injured site were prepared. We have checked the differentially expressed gene(DEG). RESULTS: The mean Tarlov value was 0.67 which indicated a significant cord injury. 4 DEG (GP3, 9, 25, 34) were detected among 40 primers after screening, the detection percentage of which was 10. In the tissues of study subjects with spinal injury, DEG was found at the injury site and cephalic lesion. DEG expressed GP3, GP9 and GP34 started expression on day 30, and GP25 was expressed on day 90. CONCLUSIONS: According to the changes in gene expression, the day 30 would be considered as the date of conversion from acute to chronic phase of cord injury. Inhibiting secondary inflammatory change and apoptosis following spinal cord injury until this period would maximize the effect of chronic phase therapy such as cell-transplantation.

Correlation Analysis of BMD in Proximal Femur and Spine According to Age / 대한골다공증학회지

OBJECTIVES: To analogize the test results through analyzing the correlation of bone mineral density (BMD) values between 2 sites (proximal femur and lumbar spine). MATERIALS AND METHODS: Among the 1557 cases that underwent BMD test on their proximal femur and lumbar spine without history of trauma or disease of the hip or lumbar region, according to their age, they were divided into 4 groups, and the T-score and Z-score of the proximal femur and lumbar spine were each investigated. RESULTS: The correlation figured out through the regression analysis was that, considering the lumbar spine value as the independent variable (L), and the proximal femur value as the dependant variable (H), the T-score was H=0.508xL-0.723 in group 1, H=0.445xL-0.649 in group 2, H=0.363xL-1.124 in group 3 and H=0.404xL-1.467 in group 4. The correlation coefficient of T-score value of the 2 sites of each group was 0.58, 0.59, 0.47, 0.54 each, and which were statistically significant. Z-score was H=0.485xL-0.514 in group 1, H=0.451xL-0.141 in group 2, H=0.390xL-0.401 in group3, L=0.897xH-0.481 in group 4. CONCLUSION: On the BMD test performed in an age group of over 40 years old, T-score and Z-score each showed significant increase and this is thought to be related to low bone mineral due to bone mineral decrease because of the old age. Also, in cases with lesion in the hip joint or spine, there is a clinical usefulness of analogizing the result of the other region with a result of a single region.

Prognostic Factors That Affect the Surgical Outcome of the Laminoplasty in Cervical Spondylotic Myelopathy

BACKGROUND: This study examined the prognostic factors that affect the surgical outcome of laminoplasty in cervical spondylotic myelopathy patients by comparative analysis. METHODS: Thirty nine patients, 26 males and 13 females, who were treated with laminoplasty for cervical myelopathy from September 2004 to March 2008 and followed up for 12 months or longer, were enrolled in this study. The mean age of the subjects was 62.4 years (range, 37 to 77 years). The patients' age, number of surgical segments, spinal cord compression ratio, segment number, level, localized marginal pattern of high signal intensity within the spinal cord in the T2 image, preoperative Japanese Orthopaedic Association Scoring System (JOA) score with the recovery ratio were compared respectively. The JOA score was used for an objective assessment of the patients' preoperative and postoperative clinical status. The recovery ratios of surgery were graded using the Hirabayashi equation. Statistical analysis was carried out using Pearson correlation analysis. RESULTS: The patients' JOA score increased from a preoperative score of 11.1 (range, 5 to 16) to a postoperative score of 14.9 (range, 7 to 17). The average recovery ratio was 65.8% (range, 0 to 100%). The number of segments with high signal changes in the T2 image, a localized marginal pattern with high signal change, signal intensity changes in the upper cervical spinal cord were inversely associated with the recovery ratio, whereas the spinal cord compression ratio showed a significant positive correlation. However, the currently known prognostic factors, such as number of surgical segment, age, and preoperative JOA score, showed no statistically significant correlation. CONCLUSIONS: The number of segments, localized marginal pattern, rostral location of signal intensity c hanges with a high signal change in the T2 image and a low spinal cord compression ratio in cervical spondylotic myelopathy patients treated by laminoplasty can indicate a poor prognosis.

Staged Management of High Energy Proximal Tibia Fractures with Severe Soft Tissue Damage

PURPOSE: To find out the efficiency of two staged operation of patients with high energy proximal tibia fracture with severe soft tissue damage, the first step being external fixation, and the second, internal fixation with plates. MATERIALS AND METHODS: The study group was the 42 patients who had followed for one year out of a group of 56, performed the first step external fixation and the second step internal fixation with plates retrospectively, from March 2003 to March 2007. The average age of the study group was 51.4, 26 men, and 16 women participating in this study. The average time of follow up was 32 months. In the final follow up, investigations of the radiological assessments and functional abilities of the bony fusion were carried out along with the complications of the soft tissue. RESULTS: The duration after the first step external fixation until second step internal fixation to be performed was 14.9 (6~40) days in average. The final bone fusion took about 15 weeks, and according to the final follow up, the range of motion of the knee was around 110.8 degrees (6.2~117 degrees). In 31 cases, only the internal fixation was performed, while in 11 cases, soft tissue reconstruction was carried out with the internal fixations. As for the complications there were 2 cases of deep soft tissue infection, 2 cases of nonunion, 1 case of malunion and 1 case of knee joint stiffness. CONCLUSION: In cases of proximal tibia fracture with severe soft tissue damage, external fixation was important to secure the safety of the fracture, carry forward the anatomical alignment, plan the soft tissue safety and manage the wound to decrease the number of microbial in the next operation, which is the internal fixation with plates.

Pathophysiology of Acute Spinal Cord Injury / 대한척추외과학회지

A spinal cord injury is an ailment that can not be treated, but through skillfully planned laboratory research we have been able to accumulate knowledge and expertise that have dramatically improved our understanding of the pathophysiology of SCI. Recent active studies on apoptosis are in now progress, and apoptosis plays a significant role in the long term loss of cells due to damage of these cells. The field is now rapidly advancing due to the development of methodologies such as immunology, molecular biology and genetics. The recent advances in the field of neural regeneration have shed a positive outlook on what once appeared to be an impossible task, that is, to regenerate neurons in the CNS.

Motor Evoked Potential and Continuous Electromyography Monitoring during Spinal Surgery / 대한정형외과학회잡지

PURPOSE: A prospective study to determine the usefulness of the spinal cord monitoring (SCM) for predicting and preventing iatrogenic nerve injury during spinal surgery. MATERIALS AND METHODS: We studied 27 cases with adolescent idiopathic scoliosis (AIS, 7), degenerative spinal deformity (DSD, 13), and spinal stenosis (7) who received decompression and SCM including MEP and EMG. Intravenous anesthesia was performed using propofol. We initially could not measure SCM because of the presence of muscle relaxants. But later could check SCM in 24 cases. We evaluated the success rate of SCM, the degree of electrical stimulus, and abnormal signals. RESULTS: The success rate of SCM was 88.9%. MEP showed an increased stimulus indicating a normal neurologic response in: AIS (26.6%), DSD (24.3%), and spinal stenosis (15.7%). EMG showed abnormal signals in 4 cases. but 3 cases had no significant nerve damage. In one case, we reinserted the pedicle screw because we found nerve irritation by the probe. None of theses cases had neural deficits after the operation. CONCLUSION: MEP and EMG allow for correction and decompression without spinal cord or nerve root injury with appropriate anesthesia technique and interpretation of abnormal signals required for SCM.

The Effect of Methylprednisolone and Riluzole on Axonal Growth after Acute Spinal Cord Injury in Rats / 대한정형외과학회잡지

PURPOSE: To determine the effect of methylprednisolone (MP) and riluzole administration on axonal growth after spinal cord injury (SCI) in rats. MATERIALS AND METHODS: Three Sprague Dawley rats (SD rat) served as controls (average 24 weeks of age) and 24 SCI SD rats scoring below 7 points on on Basso, Beattie, and Bresnahan open field test served as test subjects (total 27 SD rats; mean weight 581 g, range=427-613 g). Test subjects were divided into two groups of 12 subjects each. Group I was injected with saline (1 ml/kg) and group II was injected with MP (300 mg/kg) and riluzole (5 mg/kg) intraperitoneally. Four SD rats were sacrificed in each group at the following time points after SCI: days 1, 4, and 7. We completed behavioral testing, immunohistochemical staining and RT-PCR for chondroitin sulfate proteoglycans (CSPG), and microarrays for c-JUN, ATF-2, p53, and Elk-1. RESULTS: On behavioral testing, group II showed superior results at only day 4 after SCI (p<0.05). On RT-PCR for CSPG, optical densities were 2.06 (ratio=Group I/Group II) and 2.11 at days 4 and 7, respectively. Microarray showed that lower expression of c-JUN in group II during the entire period (p< 0.05). ATF-2 showed lower expression in group II at days 4 and 7 (p<0.05). p53 showed lower expression in group I at day 1 (p<0.05). Elk-1 showed lower expression in group I at day 1 (p<0.05) and in group II at day 7 (p<0.05). CONCLUSION: Simultaneous administration of MP and riluzole led to various changes in the MAPK pathway, and decreased CSPG. Therefore, this method has a protective effect on axonal regeneration after SCI in an SD rat model.

Correlation Between Clinical Result and Adjacent Segment Degeneration After Lumbar Spinal Fusion / 대한척추외과학회지

STUDY DESIGN: Retrospective study OBJECTIVES: To determine the relationship between clinical outcome and adjacent segment degeneration (ASD) after lumbar fusion. SUMMARY OF LITERATURE REVIEW: Few studies have analyzed the correlation between clinical outcomes and ASD. MATERIALS AND METHODS: Between January 2000 and December 2004, 217 patients who underwent lumbar spinal fusion (>2 years of follow-up) were evaluated. The patients were divided into 2 groups: one-segment (A) and two-segment (B). The UCLA grading scale was used to evaluate the prevalence of ASD on radiography. The association between clinical outcome and ASD was evaluated by Spearman's correlation. RESULTS: ASD occurred in 11.6% (13/112) of patients in group A and 15.2% (16/105) of patients in group B. The number of cases which progressed to more than 2 levels of the degenerative grade were 0 cases in group A and 13 cases (81.3%) in group B. In A, 5 out of 13 ASD cases downgraded one level in their clinical outcomes. In B, all 16 ASD cases downgraded more than one level in their clinical outcomes. Worsening in degenerative grade, was correlated with worse clinical outcome (Spearman's rho = 0.829, P <0.05). CONCLUSIONS: The association of clinical outcomes with ASD after fusion showed a significant correlation, especially association with ASD after multiple segment fusion.