• Journal of Korean Neurosurgical Society
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• 제30권2호
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• pp.144-149
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• 2001

Objective : Spinal nerve root compression occurs commonly in conditions, such as herniated nucleus pulposus, spinal stenosis, intervertebral foraminal stenosis, and trauma. However, the pathophysiolosy of the symptoms and signs related to spinal nerve root compression is poorly understood. The purpose of the present study was to assess and compare the changes of various pressures of intervertebral foraminal pressure before and after decompression. Method : After laminetomy without foraminotomy was performed, pressure sensor tip of Camino parenchymal type was located at the middle-central portion of the intervertebral foramen and anterior portion of nerve root for the foraminal pressure before decompression of the intervertebral foramen. After laminectomy with foraminotomy, the same method was used for the foraminal pressure after decompression. The authors studied 40 consecutive patients (57 disc spaces) with severe constant root pain to the lower leg, pain unrelived by bed rest, and minimal tension signs, diagnosed by MRI. Results : In patients with intervertebral foraminal stenosis, the intraforaminal pressure was decreased from $86{\pm}2.23mmHg$ to $17.1{\pm}1.51mmHg$ and in patients without stenosis, from $55.9{\pm}1.08mmHg$ to $11.9{\pm}1.25mmHg$. All patients below 20mmHg after decompression showed good outcome, but 4 cases who showed poor outcome had foraminal stenosis, posterolateral type of the herniated disc, and above 30mmHg of foraminal pressure after decompression. Conclusion : These findings suggest that if the foraminal pressure falls below 20mmHg after decompression, good outcome can be anticipated. Central type of the herniated disc shows better outcome compared to the posterolateral type.

• The Journal of Korean Physical Therapy
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• 제2권1호
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• pp.103-112
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• 1990

The intervertebral disc in the anterior portion of the function unit gives the spine its flexibility. The disc is attached closely to the vertebral endplates. Between these endplates and the annulus fibrosus, the nucleus pulposus of the lumbar disc is enclosed in a circle of unyielding tissues. Compressive pressure placed on the disc is dissipated circumferentially in a passive manner In response to the greater axial forced exerted on the lumbar spine in comparison to the cervical and thoracic spines, the nucleus pulposus has its greatest surface area in the lumbar spine. The intervertebral disc is not only structure that helps diss pate stresses placed on the spine. With flexion, extension, rotation, or shear stress, the load distribution on the function unit is shared by the intervertebral disc, anterior and posterior longitudinal ligaments, the facet joints and capsules, and other ligamentous structures like the ligamentum flavum, interspinous and supraspinous ligaments, which attach to the posterior elements of the functional unit.

• Journal of Korean Neurosurgical Society
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• 제46권1호
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• pp.16-22
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• 2009

Objective : This study was designed to investigate automated pressure-controlled discography (APCD) findings, to calculate the elastance of intervertebral discs, and to assess the relationship between the calculated elastance and disc degeneration. Methods : APCD was performed in 19 patients. There were a total of 49 intervertebral discs treated. Following intradiscal puncture, a dye was constantly injected and the intradiscal pressure was continuously measured. The elastance of the intervertebral disc was defined as unit change in intradiscal pressure per fractional change in injected dye volume. Disc degeneration was graded using a modified Dallas discogram scale. Results : The mean elastance was 43.0${\pm}$9.6 psi/mL in Grade 0, 39.5${\pm}$8.3 psi/mL in Grade 1, 30.5${\pm}$22.3 psi/mL in Grade 2, 30.5${\pm}$22.3 psi/mL in Grade 3, 13.2${\pm}$8.3 psi/mL in Grade 4 and 6.9${\pm}$3.8 psi/mL in Grade 5. The elastance showed significant negative correlation with the degree of degeneration ($R^2$=0.529, P=0.000). Conclusion: APCD liberates the examiner from the data acquisition process during discography. This will likely improve the quality of data and the reliability of discography. Elastance could be used as an indicator of disc degeneration.

• 대한기계학회논문집A
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• 제36권1호
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• pp.29-35
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• 2012

척추관 협착증은 감압술과 융합술 그리고 인공추간판 치환술 등이 있으며, 2000년대 중반부터는 인공추간판 치환술이 널리 시술되고 있다. 인공추간판의 연구는 추간판의 자유도 및 추체의 굴곡-신전, 측굴전, 축회전에 대한 해석이 핵심기술이지만, 시술 후 수년이 경과하여 발생하는 피로파손이 새롭게 큰 문제점으로 대두되고 있다. 따라서 인공추간판 연구는 슬라이딩 코어의 피로특성 및 내구성 향상에 집중되어야 한다. 본 연구에서는 세계적으로 가장 많이 사용되는 인공추간판 제품(SB Charit$\acute{e}$ III)을 기초로 유한요소모델을 제작하고, 슬라이딩 코어의 곡률반경과 마찰계수의 변화가 von-Mises 응력과 접촉압력에 미치는 영향을 평가하였다. 이와 같은 결과를 바탕으로 새로운 인공추간판 모델들 (Model-I, -II, -III)을 제안하고 일정수명 후 발생할 수 있는 슬라이딩 코어의 피로파손 거동에 대해 SB Charit$\acute{e}$ III의 결과와 비교 평가하였다.

• The Journal of Korean Physical Therapy
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• 제6권1호
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• pp.163-170
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• 1994

Low back pain is one of the moot common human diseases, striking $70\~80$ percent of the population. Many of the causes of low back pain are unknown. Yet, degenerative and mechanical changes are regarded by some as the most common cause of low back pain is physical therapy using various types of modalities and exercise. Therefore physical therapist must understand not only structure of intervertebral disk but also biomechanics of the lumbar intervertebral disk for prevent accourance of low back pain and treat patients with low back pain. The purpose of this article was to study biomechanices of the lumbar intervertebral disk and its intradiscal pressure in various position.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권4호
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• pp.243-247
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• 2014

The Spinal cage is the cage-shaped implantable medical device used to treat structural abnormalities caused by degenerative intervertebral disks. In order to secure enough space to provide the mechanical stability and the intervertebral fusion, after removing the intervertebral disc, the Spinal cage is transplanted between the intervertebral space. A hammer is used to push the spinal cage into a narrow space during the spinal cage transplant surgery. Due to the impact and pressure, damage occurs frequently on the spinal cage. In this study, a test model is constructed to measure the value of impulse generally applied on the Spinal cage. The figures of internal impulse before and after the improvement of the Spinal cage are then compared to suggest direction to improve the reliability of the spinal cage.

• The Korean Journal of Pain
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• 제34권4호
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• pp.447-453
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• 2021

Background: Provocative discography (PD) is a test that is useful in diagnosing discogenic pain (DP). In this study, to diagnose DP, we used a posterolateral approach of needle placement and followed pressure criteria laid down by the Spine Intervention Society. The aim was to identify the correlation between magnetic resonance imaging (MRI) findings (desiccation, high intensity zone and change in shape and size of the disc) and the results of PD. Methods: Records of 50 patients who underwent PD for DP were analyzed. A total of 109 PDs were performed, with 54 suspect and 55 control discs. Alternate pain generators were ruled out. Results: A total of 35 suspect discs were positive on PD. The mean disc pressure in the suspect disc was 31.9 ± 7.9 psi (range, 15-44). Of the 50 patients who underwent PD, 35 had positive MRI findings. A significant positive correlation was found only between disc desiccation and discography result (r = 0.6, P < 0.001). Logistic regression analysis revealed that only desiccation successfully predicted the result of discography (OR = 26.5, P < 0.001); a high intensity zone and a disc protrusion/extrusion had an OR 2.3 and 1.24, respectively. Disc desiccation of Pfirmann grade 3 or more had a sensitivity and specificity of 0.93 and 0.64 respectively in identifying painful discs; the positive likelihood ratio was 2.58 while the negative likelihood ratio was 0.11. Conclusions: In patients with DP, disc desiccation is the most useful MRI feature that predicts a painful disc on PD.

• 한국정밀공학회지
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• 제28권1호
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• pp.115-122
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• 2011

Recently, we have proposed a hypothesis that spinal structures have a stress sensor driving feedback mechanism, In the human spine, spinal structure could react to modify muscular action in such a way so as to equalize stress at the disc, therefore reduce the risk of injury, In this analysis, abdominal muscle and abdominal pressure, which were not included in the previous study, were added to identify those effects in spine stability during upright stance posture for the case where the intervertebral disc plays the role of mechanoreceptor, The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Muscle architecture with 46 local muscles containing paraspinal muscle and 6 rectus abdominal muscles were assigned according to the acting directions. The magnitude of 4kPa was considered for abdominal pressure. Minimization of the nucleus pressure deviation and annulus fiber average tension stress deviation was chosen for cost function. Developed model provide nice coincidence with in-vivo measurement (nucleus pressure). Analysis was conducted according to existence of co-activation of abdominal muscle and abdominal pressure. Antagonistic activity of abdominal muscle produced stability of spinal column with relatively small amount of total muscle force. In contrast to the abdominal muscle, effect of abdominal pressure was not clear that was partly depending on the assumption of constant abdominal pressure.

• Asian Spine Journal
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• 제12권6호
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• pp.1060-1068
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• 2018

Study Design: Retrospective study. Purpose: Lumbar intervertebral disc degeneration is an important cause of low back pain. Overview of Literature: Spinal fusion is often reported to have a good course for adolescent idiopathic scoliosis (AIS). However, many studies have reported that adjacent segment degeneration is accelerated after lumbar spinal fusion. Radiography is a simple method used to evaluate the orientation of the vertebral column. magnetic resonance imaging (MRI) is the method most often used to specifically evaluate intervertebral disc degeneration. The Pfirrmann classification is a well-known method used to evaluate degenerative lumbar disease. After spinal fusion, an increase in stress, excess mobility, increased intra-disc pressure, and posterior displacement of the axis of motion have been observed in the adjacent segments. Methods: we retrospectively secured and analyzed the data of 15 patients (four boys and 11 girls) with AIS who underwent a spinal fusion surgery. We studied the full-length view of the spine (anterior-posterior and lateral) from the X-ray and MRI obtained from all patients before surgery. Postoperatively, another full-length spine X-ray and lumbosacral MRI were obtained from all participants. Then, pelvic tilt, sacral slope, curve correction, and fused and free segments before and after surgery were calculated based on X-ray studies. MRI images were used to estimate the degree to which intervertebral discs were degenerated using Pfirrmann grading system. Pfirrmann grade before and after surgery were compared with Wilcoxon signed rank test. While analyzing the contribution of potential risk factors for the post-spinal fusion Pfirrmann grade of disc degeneration, we used generalized linear models with robust standard error estimates to account for intraclass correlation that may have been present between discs of the same patient. Results: The mean age of the participant was 14 years, and the mean curvature before and after surgery were 67.8 and 23.8, respectively (p<0.05). During the median follow-up of 5 years, the mean degree of the disc degeneration significantly increased in all patients after surgery (p<0.05) with a Pfirrmann grade of 1 and 2.8 in the L2-L3 before and after surgery, respectively. The corresponding figures at L3-L4, L4-L5, and L5-S1 levels were 1.28 and 2.43, 1.07 and 2.35, and 1 and 2.33, respectively. The lower was the number of free discs below the fusion level, the higher was the Pfirrmann grade of degeneration (p<0.001). Conversely, the higher was the number of the discs fused together, the higher was the Pfirrmann grade. Conclusions: we observed that the disc degeneration aggravated after spinal fusion for scoliosis. While the degree of degeneration as measured by Pfirrmann grade was directly correlated by the number of fused segments, it was negatively correlated with the number of discs that remained free below the lowermost level of the fusion.

• 척추신경추나의학회지
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• 제11권1호
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• pp.41-51
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• 2016

Objectives : This study is planned to classify Correlation between Cobbs Angle of Lumbar scoliosis and prevalence of Lumbar Intervertebral Disc. Methods : We Measured the lumbar scoliosis angle of the 114men and 91 women patients with lumbar pain in Bucheon Jaseng Korean Medicine Hospital. We use Cobb's angle method for measuring the lumbar scoliosis. And We use Magentic Resonance Imaging(MRI) for classifying the patient who has lumbar intervertebral disc or not. Results : 1.There was no statistical relation between the Cobbs angle and gender(P>0.05) 2.There was no statistical relation between the Cobbs angle and age(P>0.05) 3.There was significant relation between the direction of lumbar scoliosis and the direction of disc herniation(P<0.05) 4.There was no statistical relation between on the Cobbs angle and disc herniation. The more severe of lumbar scoliosis has not tendency of disc herniation. 5.There was no statistical relation between lumbar scoliosis Cobbs Angle on HIVD of L-spine patient and direction of disc herniation on horizontal plane. Conclusions : The direction of disc herniation has tendency of the opposite direction of lumbar scoliosis. When disc herniation, opposite side bending broad intervertebral foramen and reduce pressure.