Different Expression of Extracellular Matrix Genes: Primary vs. Recurrent Disc Herniation

OBJECTIVE: Recurrent lumbar disc herniation has been reported to occur in 5% to 15% of surgically treated primary lumbar disc herniation cases. We investigated the molecular biologic characteristics of primary herniated discs and recurrent discs to see whether the recurrent discs has the similar biological features with primary herniated discs. METHODS: Primary herniated disc and recurrent disc cells were obtained by discectomy of lumbar disc patients and cells were isolated and then taken through monolayer cultures. We compared chondrogenic and osteogenic mRNA gene expression, and western blot between the two groups. RESULTS: The mRNA gene expression of recurrent disc cells were increased 1.47* times for aggrecan, 1.38 times for type I collagen, 2.04 times for type II collagen, 1.22 times for both Sox-9 and osteocalcin, and 1.31 times for alkaline phosphatase, respectively, compared with the primary herniated lumbar disc cells (*indicates p < 0.05). Western blot results for each aggrecan, type I collagen, type II collagen, Sox-9, osteocalcin, and alkaline phosphatase were similar between the primary herniated disc cells and recurrent disc cells. CONCLUSION: These results indicate that the recurrent disc cells have similar chondrogenic and osteogenic gene expression compared to primary herniated disc cells. Therefore, we assumed that the regeneration of remaining discs could fill the previous discectomy space and also it could be one of the factors for disc recurrence especially in the molecular biologic field.

Survival Rate and Neurological Outcome after Operation for Advanced Spinal Metastasis (Tomita's Classification > or = Type 4)

PURPOSE: We investigated whether primary malignancy entities and the extent of tumor resection have an effect on the survival rate and neurological improvement in patients with spinal metastases that extend beyond the vertebral compartment (Tomita's classification > or = type 4). MATERIALS AND METHODS: We retrospectively reviewed 87 patients with advanced spinal metastasis who underwent surgery. They were divided into groups 1 and 2 according to whether they responded to adjuvant therapy or not, respectively. They were subdivided according to the extent of tumor resection: group 1, gross total resection (G1GT); group 1, subtotal resection (G1ST); group 2, gross total resection (G2GT); and group 2, subtotal resection (G2ST). The origin of the tumor, survival rate, extent of resection, and neurological improvement were analyzed. RESULTS: Group 1 had a better survival rate than group 2. The G1GT subgroup showed a better prognosis than the G1ST subgroup. In group 2, the extent of tumor resection (G2GT vs. G2ST) did not affect survival rate. In all subgroups, neurological status improved one month after surgery, however, the G2ST subgroup had worsened at the last follow-up. There was no local recurrence at the last follow-up in the G1GT subgroup. Four out of 13 patients in the G2GT subgroup showed a local recurrence of spinal tumors and progressive worsening of neurological status. CONCLUSION: In patients with spinal metastases (Tomita's classification > or = type 4), individuals who underwent gross total resection of tumors that responded to adjuvant therapy showed a higher survival rate than those who underwent subtotal resection. For tumors not responding to adjuvant therapy, we suggest palliative surgical decompression.

Load Sharing Mechanism Across Graft-Bone Interface in Static Cervical Locking Plate Fixation

OBJECTIVE: This study is a retrospective clinical study over more than 4 years of follow up to understand the mechanism of load sharing across the graft-bone interface in the static locking plate (SLP) fixation compared with non-locking plate (NLP). METHODS: Orion locking plates and Top non-locking plates were used for SLP fixation in 29 patients and NLP fixation in 24 patients, respectively. Successful interbody fusion was estimated by dynamic X-ray films. The checking parameters were as follows : screw angle (SA) between upper and lower screw, anterior and posterior height of fusion segment between upper and lower endplate (AH & PH), and upper and lower distance from vertebral endplate to the end of plate (UD & LD). Each follow-up value of AH and PH were compared to initial values. Contributions of upper and lower collapse to whole segment collapse were estimated. RESULTS: Successful intervertebral bone fusion rate was 100% in the SLP group and 92% in the NLP group. The follow-up mean value of SA in SLP group was not significantly changed compared with initial value, but follow-up mean value of SA in NLP group decreased more than those in SLP group (p=0.0067). Statistical analysis did not show a significant difference in the change in AH and PH between SLP and NLP groups (p>0.05). Follow-up AH of NLP group showed more collapse than PH of same group (p=0.04). The upper portion of the vertebral body collapsed more than the lower portion in the SLP fixation (p=0.00058). CONCLUSION: The fused segments with SLP had successful bone fusion without change in initial screw angle, which was not observed in NLP fixation. It suggests that there was enough load sharing across bone-graft interface in SLP fixation.

Long Term Efficacy of Posterior Lumbar Interbody Fusion with Standard Cages alone in Lumbar Disc Diseases Combined with Modic Changes

OBJECTIVE: Posterior lumbar interbody fusion (PLIF) is considered to have the best theoretical potential in promoting bony fusion of unstable vertebral segments by way of a load sharing effect of the anterior column. This study was undertaken to investigate the efficacy of PLIF with cages in chronic degenerative disc disease with Modic degeneration (changes of vertebral end plate). METHODS: A total of 597 patients underwent a PLIF with threaded fusion cages (TFC) from 1993 to 2000. Three-hundred-fifty-one patients, who could be followed for more than 3 years, were enrolled in this study. Patients were grouped into 4 categories according to Modic classification (no degeneration : 259, type 1 : 26, type 2 : 55, type 3 : 11). Clinical and radiographic data were evaluated retrospectively. RESULTS: The clinical success rate according to the Prolo's functional and economic outcome scale was 86% in patients without degeneration and 83% in patients with Modic degeneration. The clinical outcomes in each group were 88% in type 1, 84% in type 2, and 73% in type 3. The bony fusion rate was 97% in patients without degeneration and 83% in patients with Modic degeneration. The bony fusion rate in each group was 81% in type 1, 84% in type 2, and 55% in type 3. The clinical success and fusion rates were significantly lower in patients with type 3 degeneration. CONCLUSION: The PLIF with TFC has been found to be an effective procedure for lumbar spine fusion. But, the clinical outcome and bony fusion rates were significantly low in the patients with Modic type 3. The authors suggest that PLIF combined with pedicle screw fixation would be the better for them.

Intradural Lumbar Disc Herniations Associated with Epidural Adhesion : Report of Two Cases

Intradural lumbar disc herniation (ILDH) is rare. In this report, authors present 2 cases of ILDHs associated with severe adhesion between the dural sac and posterior longitudinal ligament. In a 40-year-old man, ILDH occurred in association with epidural adhesion due to ossification of the posterior longitudinal ligament (OPLL). In other 31-year-old man, ILDH occurred in presence of epidural adhesion due to previous spine surgery.

Surgical Treatment of Primary Spinal Tumors in the Conus Medullaris

Objective: The objective of this study was to evaluate the characteristics and surgical outcome of the conus medullaris tumors. Methods: We retrospectively reviewed 26 patients who underwent surgery for conus medullaris tumor from August 1986 to July 2007. We analyzed clinical manifestation, preoperative MRI findings, extent of surgical resection, histopathologic type, adjuvant therapy, and outcomes. Results: There were ependymoma (13), hemangioblastoma (3), lipoma (3), astrocytoma (3), primitive neuroectodermal tumor (PNET) (2), mature teratoma (1), and capillary hemangioma (1) on histopathologic type. Leg pain was the most common symptom and was seen in 80.8% of patients. Pain or sensory change in the saddle area was seen in 50% of patients and 2 patients had severe pain in the perineum and genitalia. Gross total or complete tumor resection was obtained in 80.8% of patients. On surgical outcome, modified JOA score worsened in 26.9% of patients, improved in 34.6%, and remained stable in 38.5%. The mean VAS score was improved from 5.4 to 1.8 among 21 patients who had lower back pain and leg pain. Conclusion: The surgical outcome of conus medullaris tumor mainly depends on preoperative neurological condition and pathological type. The surgical treatment of conus medullaris tumor needs understanding the anatomical and functional characteristics of conus meudllaris tumor for better outcome.

Retraction: Cortical Margining Capabilities of Fins Associated with Ventral Cervical Spine Instrumentation

No abstract available.

Surgical Treatments for Lumbar Disc Disease in Adolescent Patients; Chemonucleolysis / Microsurgical Discectomy/ PLIF with Cages

The herniated lumbar disc (HLD) in adolescent patients is characterized by typical discogenic pain that originates from a soft herniated disc. It is frequently related to back trauma, and sometimes it is also combined with a degenerative process and a bony spur such as posterior Schmorl's node. Chemonucleolysis is an excellent minimally invasive treatment having these criteria: leg pain rather than back pain, severe limitation on the straight leg raising test (SLRT), and soft disc protrusion on computed tomography (CT). Microsurgical discectomy is useful in the cases of extruded or sequestered HLD and lateral recess stenosis due to bony spur because the nerve root is not decompressed with chymopapain. Spinal fusion, like as PLIF, should be considered in the cases of severe disc degeneration, instability, and stenosis due to posterior central bony spur. In our study, 185 adolescent patients, whose follow-up period was more than 1 year (the range was 1 - 4 years), underwent spinal surgery due to HLD from March, 1998 to December, 2002 at our institute. Among these cases, we performed chemonucleolysis in 65 cases, microsurgical discectomy in 94 cases, and posterior lumbar interbody fusion (PLIF) with cages in 33 cases including 7 reoperation cases. The clinical success rate was 91% for chemonucleolysis, 95% for microsurgical disectomy, and 89% for PLIF with cages, and there were no non- union cases for the PLIF patients with cages. In adolescent HLD, chemonucleolysis was the 1st choice of treatment because the soft adolescent HLD was effectively treated with chemonucleolysis, especially when the patient satisfied the chemonucleolysis indications.

Cortical Margining Capabilities of Fins Associated with Ventral Cervical Spine Instrumentation

Fins incorporated into the design of a dynamic cervical spine implant have been employed to enhance axial load- bearing ability, yet their true biomechanical advantages, if any, have not been defined. Therefore, the goal of this study was to assess the biomechanical and axial load-bearing contributions of the fin components of the DOC ventral cervical stabilization system. Eighteen fresh cadaveric thoracic vertebrae (T1-T3) were obtained. Three test conditions were devised and studied: Condition A (DOC implants with fins were placed against the superior endplate and bone screws were not inserted) ; Condition B (DOC implant without fins was placed and bone screws were inserted) ; and Condition C (DOC implant with fins were placed against the superior endplate and bone screws were inserted). Specimens were tested by applying a pure axial compressive load to the superior platform of the DOC construct, and load-displacement data were collected. Condition C specimens had the greatest stiffness (459 +/- 80N/mm) and yield load (526 +/- 168N). Condition A specimens were the least stiff (266 +/- 53N/mm), and had the smallest yield loads (180 +/- 54N). The yield load of condition A plus condition B was approximately equal to that of condition C, with condition A contributing about one-third and condition B contributing two-thirds of the overall load-bearing capacity. Although the screws alone contributed to a substantial portion of axial load-bearing ability, the addition of the fins further increased load-bearing capabilities.

Primary Intraspinal Primitive Neuroectodermal Tumor at Conus Medullaris

A primary intraspinal primitive neuroectodermal tumor is very rare, with only 24 cases having been reported in the literature. In general this type of tumor is treated with surgery followed by radiotherapy and chemotherapy; however, the prognosis still remains poor. The case of a primary intraspinal primitive neuroectodermal tumor, at the conus medullaris in a 17 year old male patient is presented. He had sufferred from paraparesis, urinary difficulty and lower back pain of 1 month duration. A thoracolumbar MRI demonstrated a 2x2x8cm isointense intraspinal mass, on T1-weighted images, with strong contrast enhancement from the T11 to L2 level. There was no clinical or radiological evidence for the existence of an intracranial tumor. A histological examination revealed a small round cell tumor and immunohistochemical characteristics of PNET. The clinical, radiological and pathological features are discussed with a review of the literatures.

Surgical Treatment of Adjacent Segment Degeneration after Spinal Fusion in Degenerative Lumbar Disc Disease

OBJECTIVE: We experienced some cases of adjacent segment degeneration after spinal fusion and treated them by various reoperation methods. The authors report an evaluation of causes of adjacent segment degeneration after spinal fusion and treatment methods. METHODS: Sixteen patients was admitted to our hospital due to adjacent segment degeneration after spinal fusion from November 1997 to May 2001 and we operated 11 patients among 16 patients with various surgical methods. We analyzed clinical diagnosea, surgical methods, and disc degeneration status of adjacent segment following spinal fusion on 1st operation and 2nd operation, and also evaluated the clinical symptoms, type of adjacent segment degeneration, and time interval between the 1st operation and the 2nd operation. RESULTS: Clinical diagnoses on 1st operation were degenerative spondylolisthesis of four cases, chronic degenerative disc disease with spinal stenosis of six cases, and recurred herniated lumbar disc disease of one case. We treated eight cases by posterior lumbar interbody fusion, one case by 360degrees fusion, and two cases by pedicle screw fixation only. Disc degeneration on adjacent segment to spinal fusion existed already in nine among 11 patients before spinal fusion. Types of adjacent segment degeneration after spinal fusion were disc degeneration of two cases, lumbar instability of three cases, lumbar stenosis of four cases, and lumbar instability and stenosis of two cases. Most patients complained of low back pain due to disc degeneration and instability, and some patients complained of leg and buttock pain due to stenosis. Time interval from 1st operation to reoperation was 20 months through 99 months, mean time interval was 57 months. CONCLUSION: Inevitable compensatory mechanism occurs at adjacent segment after fusion, because of stress concentration and alteration of biomechanics after fusion. But, we achieve excellent or good results of reoperation surgical treatment for adjacent segment degeneration after spinal fusion.

Melanotic Schwannoma in Cervical Spine: A Case Report

Primary melanotic schwannoma in spinal cord is a very uncommon disorder, eight cases of melanotic schwannoma in spinal cord have been found in the literature. We present a case report of a patient with an intradural, extramadullary melanotic schwannoma in cervical spine and the literature on melanotic schwannoma is reviewed. The proposed theories on the origin of these tumors and treatment are discussed.

Clinical Analysis of Anterior Lumbar Interbody Fusion for Failed Back Surgery Syndrome

OBJECTIVE: To evaluate the role of anterior lumbar interbody fusion in treatment of failed back surgery syndrome, the authors retrospectively analyzed the result of anterior lumbar interbody fusion performed in our institute. METHODS: Fifteen FBSS patients due to variable causes have been treated with anterior lumbar interbody fusion in our institute from April 1994 to June 1999. We analyzed clinical changes in 15 patients who were followed up for an average of 23 months. RESULTS: The etiologies of FBSS were post operative discitis(6 cases), post operative instability(3 cases), post operative adhesion(5 cases), and recurrence(1 case). These fifteen FBSS patients were treated with anterior lumbar interbody fusion. The overall treatment outcome was satisfactory(excellent and good) in 11 cases. Three patients were slightly improved, but post operative low back pain was remained. One patient who had underwent nerve root injury due to pedicle screw insertion showed no improvement. CONCLUSION: We conclude that the anterior lumbar interbody fusion for FBSS seems to be safe and favorable treatment in selective patients, because low incidence of nerve injury risk and post-operative infection.

The Result of Posterior Microforaminotomy for Posterolateral Herniation of Cervical Discs

OBJECTIVE: To evaluate the effectiveness of posterior microforaminotomy in treatment of posterolateral cervical disc herniation, the authors retrospectively analyzed the result of posterior microforaminotomy in our institute. PATIENTS AND METHODS: Ten patients with radiculopathy due to posterolateral cervical disc herniation have been treated with posterior microforaminotomy from August 1996 to July 2000. We analyzed clinical results in all patients who were followed up for an average of 10 months. RESULTS: The mean age was 47.2 years and all patients were treated with posterior microforaminotomy as primary treatment. one patient was received anterior cervical interbody fusion with iliac bone 12 years before. Clinical improvement in the last follow-up were seen in all patients and there were no complications. CONCLUSION: Microcervical foraminotomy is considered useful operative method for posterolateral soft disc herniation. We conclude that the posterior microforaminotomy for radiculopathy due to soft posterolateral cervical disc herniation seems to be safe and effective in selective patients.

Surgical Treatment of Foramen Magnum & High Cervical Spinal Cord Tumor

OBJECTIVE: The authors reviewed 51 patients of spinal cord tumor located at the craniovertebral junction and high cervical area to determine which factors influenced resectability, complications, and postoperative outcomes. METHODS: Radiological examinations, clinical data, and operation notes were evaluated, and additional follow-up information was obtained from outpatient examinations. The mean follow-up period was 3.5 years RESULTS: The most common neurological findings were motor deficit(72.5%) and sensory change(47.1%). There was no clinical finding that is considered as pathognomic. Meningioma(18 cases, 35.3%) was the most common tumor in this region. Total removal was achieved in 45 patients. There was no surgical mortality. Immediate postoperative motor weakness were encounted in 11 cases(21.6%) which improved in long term follow-up except two patients. Conclusions: The location and relationship of the tumor to surrounding struncture determine its resectability. Postoperative results were related to the preoperative neurological status and pathological findings.

Influence of Trauma on the Surgical Outcome in Patients with Ossification of the Posterior Longitudinal Ligament of the Cervical Spine

No abstract available.

Diagnostic Significance of Discography on Multiple Lumbar Disc Herniation

No abstract available.

Histologically Confirmed Bone Formation in the Carbon Fiber Cage Implant

The authors report the first case of histologically confirmed bone formation in the carbon fiber cage implant which used in posterior lumbar interbody fusion. A case of degenerative lumbar disc desease was treated by posterior lumbar interbody fusion with carbon fiber cage implant and local bone from posterior decompression. One year after the operation the cage was migrated into the spinal canal and compressed dural sac and nerve root. The cage was removed and investigated by light microscope. The histologic examination revealed viable bony traveculae in the cage. This finding suggest autogenous bone in the cage has a biologic bone-growth function after interbody fusion.

Clinical Results of Posterior Lumbar Interbody Fusion with BAK Cage

OBJECTIVE: In the management of degenerative conditions of the lumbar spine, spinal fusion is a popular management option and posterior interbody fusion is gaining wide acceptance for the treatment of segmental instability, spondylolisthesis, and discogenic pain. Many methods have been described, including use of autograft or allograft bone, in either structural or nonstructural form, with or without additional fixation. METHOD: The authors retrospectively analyzed 102 cases of posterior lumbar interbody fusion with BAK cage from March 1993 to April 1998. All patients have been followed for 24 to 56 months. Postoperative clinical and radiological changes are evaluated by Mcnab criteria and dynamic lumbar spine lateral measurement. RESULTS: Stable bony fusion was accomplished in 81.9% of patients at 12 months, in 87.4% of patients at 24months, and in 91.2% of patients at 3 years after surgery and their overall outcome was also remarkable(excellent: 42.2%, good: 49.1%). Postoperative correction of slipping was average 3.1mm in spondylolisthesis group. Seventy-eight percent of the previously employed patients returned to work by 24 months after surgery, and 94% were working at 3 years after surgery. CONCLUSION: The results of this study strongly imply that the BAK cage is safe and effective in the management of certain forms of degenerative conditions of lumbar spine. However proper patient selection is critical and experienced and properly trained spinal surgeons should perform this procedure.

The Evaluation of Prognosis in Syringomyelia Using SPAMM(Spatial Moduation of Magnetiztion) - MRI

The clinical significance of cystic fluid motion in syringomyelia is uncertain. Because of its sensitivity to fluid motion, MR imaging was used to investigate fluid dynamics in syringomyelia by various tecniques. SPAMM (Spatial Modulation of Magnetization) MRI is one of these techniques which shows the fluid motion of syrinx in syringomyelia. After taking preimaging pulse sequence, the MR images show periodic bands due to the magnetic modulation. Motion between the time of banding and image formation is directly demonstrated as a corresponding displacement of the bands. The authors evaluated 7 patients of syringomyelia due to various causes with SPAMM MRI technique and compared preoperative SPAMM MRI findings and clinical results, postoperative size of syrinx. Among 4 patients of syringomyelia with Arnold-Chiari malformation, 3 patients showed band shift representing fluid motion of syrinx on SPAMM MRI. Clinical results of these patients were good and the size of postoperative syrinx decreased. Three patients of posttraumatic or postmeningitic syringomyelia who did not show band shift on SPAMM MRI had poor clinical courses and the sizes of postoperative syrinx remained unchanged. These results indicate that SPAMM MRI may be useful in dete rmining the type of treatment and predicting clinical results in syringomyelia.