• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1364-1367
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• 2003

These days, spinal interbody arthrodesis using fusion cage is very popular. The cage used for the spinal interbody arthrodesis is mainly inserted from the posterior of the spine. Accordingly, there could possibly occur damages at posterior and results in instability of structure. Moreover, one or two cages are inserted depending on the patients. In this study, it is attempted to evaluate the stability quantitatively by comparing two cases where one and two cages are inserted. For this purpose, a very fine 3-dimensional finite element model of vertebra is generated from the MRI data. From this vertebra model, two models are made: one with one cage and the other with two cages. Finally, finite element analys is performed for these two models and both of the mechanical behaviors are examined In addition, the effect on the stability is evaluated and compared quantitatively.

• Composites Research
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• v.25 no.4
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• pp.98-104
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• 2012

In recent years, degenerative spinal instability has been effectively treated with a cage. However, little attention is focused on the stiffness of the cage. Recent advances in the medical implant industry have resulted in the use of medical carbon fiber reinforced polymer (CFRP) cages. The biomechanical advantages of using different cage material in terms of stability and stresses in bone graft are not fully understood. A previously validated three-dimensional, nonlinear finite element model of an intact L2-L5 segment was modified to simulate posterior interbody fusion cages made of CFRP and titanium at the L4-L5 disc with pedicle screw, to investigate the effect of cage stiffness on the biomechanics of the fused segment in the lumbar region. From the results, it could be found that the use of a CFRP cage would not only reduce stress shielding, but it might also have led to increased bony fusion.

• Composites Research
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• v.34 no.3
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• pp.186-191
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• 2021

The lumbar spinal fusion is a treatment performed to restore the stability of the degenerated lumbar. In this study, the intervertebral discs between two or more segments are removed and a bone graft is inserted to harden the segments. The pedicle screw system is inserted to vertebral bodies to fix two or more segments so that they can be firmly fused. In this study, a total of 7 patient-specific lumbar finite element models were created and pedicle screw systems were installed. The connecting rods made of titanium and CFR-PEEK was inserted to the generated models. Finite element analysis was conducted for four representative spine behaviors and statistical analysis was performed to investigate the biomechanical effects by the material properties of connecting rods. The intradiscal pressure of adjacent segments and the range of motion of the joints of each segment were investigated. In the subjects who used CFR-PEEK instead of Ti for connecting rods, the intradiscal pressure of adjacent segments tend to decrease and the range of motion of each segment tend to increase. However, no statistically significant difference in tendency was observed under all loading conditions.

• Journal of the Korean Orthopaedic Association
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• v.52 no.1
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• pp.65-72
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• 2017

Purpose: The purpose of this study was to evaluate the radiologic features of juxtafacet cyst and determine the correlation between these features and clinical outcome. Materials and Methods: We analyzed a total of 23 patients. The degree of facet joint degeneration was classified using the Fujiwara method. The facet joint angles were measured with an magnetic resonance imaging to determine whether there was a difference between the cystic lesion that was occupied and the cystic lesion that was not occupied. Disc degeneration was measured by the Pfirrmann classification method. The clinical result was evaluated using the Oswestry disability index score and visual analogue scale. Results: The L4-5 level of juxtafacet cyst was mostly affected, as found in previous studies. Facet joint arthritis was more severe within the side with the cystic lesion. Significant correlation was found between disc degeneration and juxtafacet joint cyst. All patients underwent wide decompression and fusion. Clinical result was excellent. No patients had signs of recurrence during the follow-up periods. Conclusion: Juxtafacet cyst has a significant correlation with facet joint degeneration. Therefore, aggressive surgical treatment-not just simple cyst excision-should be considered as the treatment option for juxtafacet cyst associated with degenerative lumbar disease.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.419-426
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• 2021

Purpose: In the surgical treatment of pyogenic lumbar spondylodiscitis, screw insertion at the affected vertebra has been avoided because of biofilm formation, and the risk of infection recurrence. The authors analyzed the success rate of infection treatment while minimizing the number of instrumented segments by inserting pedicle screws into the affected vertebrae. Therefore, this study examined the usefulness of this technique. Materials and Methods: From January 2000 to June 2018, among patients with pyogenic lumbar spondylodiscitis treated surgically, group A consisted of patients with pedicle screws inserted directly at the affected vertebrae (28 cases), and group B underwent fusion by inserting screws at the adjacent normal vertebrae due to bone destruction of the affected vertebral pedicle (20 cases). The classified clinical results were analyzed retrospectively. All patients were treated via the posterior-only approach, so the affected disc and sequestrum were removed. Posterior interbody fusion was performed with an autogenous strut bone graft, and the segments were then stabilized with pedicle screw systems. The hospitalization period, operation time, amount of blood loss, EQ-5D index, duration of intravenous antibiotics, and the clinical and radiological results were analyzed. Results: In group A, the number of instrumented segments, operation time, blood loss, and EQ-5D index at one month postoperatively showed significant improvement compared to group B. There were no significant differences in the duration of antibiotic use, hospitalization, radiological bone union time, sagittal angle correction rate, and recurrence rate. Conclusion: Minimal segmental fixation, in which pedicle screws were inserted directly into the affected vertebrae through the posterior approach, reduced the surgery time and blood loss, preserved the lumbar motion by minimizing fixed segments and showed rapid recovery without spreading or recurrence of infection. Therefore, this procedure recommended for the surgical treatment of lumbar pyogenic spondyodiscitis.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.16 no.2
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• pp.79-86
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• 2021

Objectives This study aimed to assess the role of complex Korean medicinal treatment with Chuna manual therapy in two patients with chronic pain after posterior lumbar fusion surgery. Methods A retrospective analysis was performed on 2 patients postoperatively based on their medical records. The surgery regions were verified using T2-weighted axial magnetic resonance imaging. Patients with chronic pain after spondylolisthesis posterior lumbar fusion surgery received complex Korean medicinal treatment with Chuna manual therapy during hospitalization. Numeric rating scale (NRS) in the degree of 0-10 and Oswestry disability index (ODI) were measured before and after treatment. Results Case 1 had an improved NRS score from 7 to 4, and Case 2 had an improved NRS score from 7 to 5. In addition, ODI score improved in both cases. Conclusions Complex Korean medicinal treatment with Chuna manual therapy is effective for relief from chronic pain after posterior lumbar fusion surgery.

• The Journal of the Korean bone and joint tumor society
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• v.15 no.2
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• pp.138-145
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• 2009

Purpose: Giant cell tumor of the spine is very rare, and the treatment is very difficult. However, surgical techniques and diagnostic modalities are developed, and postoperative functional results are improved. To evaluate the efficacy of total spondylectomy for giant cell tumor of the spine, the clinical results of the surgical treatments for the giant cell tumor of the spine with intralesional curettage or total spondylectomy were evaluated. Materials and Methods: From April 1987 to March 2006, 10 patients who were underwent surgical treatments using total spondylectomy or intralesional curettage were studied. There were 3 men and 7 women. The mean age of the patients was 32 years (range, 25~44 years). The mean duration of follow-up was 8 years (range, 3~15 years). Locations of the tumor were 2 cervical spines, 4 thoracic spines, 2 lumbar spines and 2 sacrum. Initial main symptom of 10 patients was pain, and 7 patients had neurologic impairments too. Four patients were treated with total spodylectomy using anterior and posterior combined approach, 1 patient was treated with total sacrectomy using posterior approach only, and 5 patients were treated with intralesional curettage using anterior approach. Results: Nine patients improved pain and neurologic impairments. Local recurrences developed in 4(40%) patients (2 cervical spines, 1 thoracic spine, 1 sacrum). While a local recurrence developed from 5 total spondylectomy, 3 local recurrences developed from 5 intralesional curettage. Conclusion: Local recurrence rate after surgical treatment with intralesional curettage for the giant cell tumor of the spine was very high. Total spondylectomy using anterior and posterior approach is advisable to prevent the local recurrence after surgical treatment.