Publications (30)37.8 Total impact
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Article: Analysis of single nucleotide polymorphism in adolescent idiopathic scoliosis in Korea: for personalized treatment.
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ABSTRACT: Purpose: The incidence of adolescent idiopathic scoliosis (AIS) has rapidly increased, and with it, physician consultations and expenditures (about one and a half times) in the last 5 years. Recent etiological studies reveal that AIS is a complex genetic disorder that results from the interaction of multiple gene loci and the environment. For personalized treatment of AIS, a tool that can accurately measure the progression of Cobb's angle would be of great use. Gene analysis utilizing single nucleotide polymorphism (SNP) has been developed as a diagnostic tool for use in Caucasians but not Koreans. Therefore, we attempted to reveal AIS-related genes and their relevance in Koreans, exploring the potential use of gene analysis as a diagnostic tool for personalized treatment of AIS therein. Materials and Methods: A total of 68 Korean AIS and 35 age- and sex-matched, healthy adolescents were enrolled in this study and were examined for 10 candidate scoliosis gene SNPs. Results: This study revealed that the SNPs of rs2449539 in lysosomal-associated transmembrane protein 4 beta (LAPTM4B) and rs5742612 in upstream and insulin-like growth factor 1 (IGF1) were associated with both susceptibility to and curve severity in AIS. The results suggested that both LAPTM4B and IGF1 genes were important in AIS predisposition and progression. Conclusion: Thus, on the basis of this study, if more SNPs or candidate genes are studied in a larger population in Korea, personalized treatment of Korean AIS patients might become a possibility.Yonsei medical journal 03/2013; 54(2):500-9. · 0.77 Impact Factor -
Article: Changes in vitamin d status after surgery in female patients with lumbar spinal stenosis and its clinical significance.
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ABSTRACT: STUDY DESIGN.: A prospective cohort study. OBJECTIVE.: To demonstrate the changes in vitamin D status after surgery in female patients with lumbar spinal stenosis (LSS), and its correlation with surgical outcomes. SUMMARY OF BACKGROUND DATA.: In patients with LSS, general health including walking ability and nutritional status can be markedly improved by decompressive surgery. It can be hypothesized that such improvement may have a positive effect on their vitamin D status. METHODS.: In total, 31 female patients who underwent decompression and instrumented posterolateral fusion for LSS were enrolled. Serum 25-hydroxyvitamin D (25-OHD) level was measured before the surgery and at 1 year postoperative visit. According to serum 25-OHD level, patients were classified into 3 groups: (1) deficient group, when 25-OHD level was less than 20 ng/mL (< 50 nmol/L); (2) insufficient group, when 25-OHD level was between 20 to 30 ng/mL (50 nmol/L ≤ 25-OHD < 75 nmol/L); (3) and normal group, when 25-OHD level was 30 ng/mL or more (≥75 nmol/L). The Oswestry Disability Index (ODI) score and health-related quality of life (EQ-5D) were compared according to the level of 25-OHD at 1 year postoperatively. RESULTS.: Preoperatively, there were 20 patients in the deficient group, 11 patients in the insufficient group and no patient in the normal group. There were no differences in age, body mass index, preoperative ODI scores, preoperative EQ-5D index scores, and EQ-5D visual analogue scale scores between the 2 groups. Mean preoperative 25-OHD level was 15.8 ng/mL (range, 5.2-29.4 ng/mL) and increased to 19.5 ng/mL (range, 6.3-47.7 ng/mL) 1 year after surgery (P = 0.075). Significant increase of 25-OHD was noted only in the deficient group (P = 0.017). Postoperatively, there were 18 patients in the deficient group, 8 patients in the insufficient group, and 5 patients in the normal group. In the postoperative deficient group, postoperative ODI scores and EQ-5D index scores showed significantly worse outcomes than those in the other groups. The changes in serum 25-OHD level were significantly correlated with the changes in ODI scores (r = -0.580; P = 0.001) and with the changes in EQ-5D index scores (r = 0.379; P = 0.035). In all the groups, postoperative ODI scores (r = -0.665; P < 0.001) and EQ-5D index scores (r = 0.601; P < 0.001) were significantly correlated with postoperative 25-OHD level. CONCLUSION.: Vitamin D deficiency was common in patients with LSS. However, vitamin D status was improved after decompressive surgery, and postoperative 25-OHD level was significantly correlated with surgical outcomes.Spine 07/2012; 37(21):E1326-30. · 2.08 Impact Factor -
Article: The biomechanical effect of pedicle screws' insertion angle and position on the superior adjacent segment in 1 segment lumbar fusion.
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ABSTRACT: A finite element analysis. To investigate the association between the position of an inserted pedicle screw and the corresponding facet contact force or intradiscal pressure. Although superior facet joint violation by pedicle screws is not an uncommon occurrence in instrumented lumbar fusion surgery, its actual biomechanical significance is not well understood. Furthermore, the association between the position of the pedicle screw and the stress on the corresponding disc/facet joint has yet to be investigated. According to the positions of pedicle screws in L4 of the L4-L5 lumbar fusion, 4 L4-L5 fusion models were simulated. These models included the violation of both L3-L4 superior facet joints by pedicle screws (facet joint violation [FV] model), the nonencroachment of both L3-L4 superior facet joints by pedicle screws (facet joint preservation [FP] model), and the removal state of pedicle screws in the FV model (removal of violated pedicle screws [rFV] model). The facet joint contact [FC] model represented the scenario in which the pedicle screws did not encroach upon either facet joint but were inserted close to the L3-L4 facet joint surface. Moreover, the uninstrumented fusion [UF] model represented the uninstrumented L4-L5 fusion. In each scenario, the intradiscal pressures and facet contact forces at the L2-L3 and L3-L4 segments were analyzed under extension and torsion moments. The FV model yielded the greatest increases in facet contact force and intradiscal pressure at the L3-L4 segment under extension and torsion moments. Following the FV model, the increases in intradiscal pressure and facet contact force were the second highest in the FC model followed by the FP model. Furthermore, the rFV model represented prominent reductions of previously increased facet contact force and intradiscal pressure at the L3-L4 segment. In models of 1-segment lumbar fusion surgery, the positions of pedicle screws were closely linked with corresponding disc stresses and facet contact forces. However, even in cases of facet violation by pedicle screws, removal of the pedicle screw after fusion completion can reduce facet contract forces and disc stresses under both extension and torsional moments.Spine 11/2011; 37(19):1637-44. · 2.08 Impact Factor -
Article: A spinal cord astrocytoma and its concurrent osteoblastic metastases at the time of the initial diagnosis: a case report and literature review.
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ABSTRACT: Bone metastasis from a spinal cord astrocytoma has been reported only twice in the English medical literature. It is generally known that bone metastasis is found after the initial diagnosis with/without intervening surgery rather than being found at the time of the diagnosis of astrocytoma. The purpose of this article is to report for the first time a case of concurrent bone metastasis from a spinal cord astrocytoma at the time of diagnosing the spinal cord astrocytoma.Korean journal of radiology: official journal of the Korean Radiological Society 09/2011; 12(5):620-5. · 1.32 Impact Factor -
Article: Surgical outcome of lumbar fusion surgery in patients with Parkinson disease.
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ABSTRACT: Retrospective study. To investigate the overall surgical outcome of lumbar fusion surgery in patients with Parkinson disease (PD). SUMMARY OF BACK GROUND DATA: Poor bone quality and muscular dysfunction are important clinical manifestations connected with musculoskeletal diseases in PD patients. These secondary changes caused by PD often result in spinal pathology, indicating spine operations for some patients with scoliosis, kyphosis, osteoporotic fracture, or degenerative spondylosis. However, little is known about the surgical outcome or prognosis of spine surgery in PD patients. Lumbar fusion surgery was performed on 20 patients who had PD and degenerative spinal diseases. At the time of lumbar fusion surgery, the mean duration of PD, age, sex, the preoperative visual analog pain scale (VAS, 0 to 100 mm) for low back pain, Hoehn and Yahr staging, and other comorbidities were evaluated. Patients' postoperative clinical outcome was measured using the criteria of Kim and Kim and VAS for back pain. Radiographic assessment was made using plain films and a dynamogram. At the time of the spine surgery, Hoehn and Yahr staging of PD was from 1 to 2 in all patients. Only 1 patient had a satisfactory outcome; a good result according to Kim and Kim's criteria. The average postoperative VAS (mm) was 55.2, whereas the mean preoperative VAS (mm) was 53.9. Radiological assessment showed fusion status in 15 patients and probably no solid fusion mass in 5 patients. A poor surgical outcome would be inevitable because of the worsening of symptoms owing to the natural history of PD. Therefore, our current study suggested surgical indication should be exercised cautiously in the patients with PD and spinal stenosis.Journal of spinal disorders & techniques 06/2011; 25(7):351-5. · 1.21 Impact Factor -
Article: The quantitative assessment of risk factors to overstress at adjacent segments after lumbar fusion: removal of posterior ligaments and pedicle screws.
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ABSTRACT: Finite element method. To investigate the changes in the disc stress and range of motion (ROM) at adjacent segments after lumbar fusion based on whether or not pedicle screws are removed and whether or not the continuity of the proximal posterior ligament complex (PLC) is preserved. The ablation of proximal PLC continuity and the presence of pedicle screws have been reported to affect the biomechanics at adjacent segments after lumbar fusion. However, there have been few studies regarding the quantitative assessment of their contribution to overstress at adjacent segments after lumbar fusion. In the validated intact lumbar finite element model (L2-L5), four types of L3-L4 fusion models were simulated. These models included the preservation of the PLC continuity with pedicle screws (Pp WiP), the preservation of PLC continuity without pedicle screws (Pp WoP), the sacrifice of PLC with pedicle screws (Sp WiP), and the sacrifice of PLC without pedicle screws (Sp WoP). In each scenario, the ROM, maximal von Mises stress of discs, and the facet joint contract force at adjacent segments were analyzed. RESULTS.: Among the four models, the Sp WiP yielded the greatest increase in the ROM and the maximal von Mises stress of the disc at adjacent segments under four moments. Following the SP WiP, the order of increase of the ROM and the disc stress was Pp WiP, Sp WoP, and Pp WoP. Furthermore, the increase of ROM and disc stress at the proximal adjacent segment was more than at the distal adjacent segment under all four moments in each model. The facet joint contact was also most increased in the Sp WiP under extension and torsion moment. The current study suggests that the preservation of the PLC continuity or the removal of pedicle screws after complete fusion could decrease the stress at adjacent segments, and their combination could act synergistically.Spine 05/2011; 36(17):1367-73. · 2.08 Impact Factor -
Article: Value of preoperative pulmonary function test in flaccid neuromuscular scoliosis surgery.
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ABSTRACT: Retrospective study. To evaluate the prognostic value of preoperative pulmonary function test (PFT) for postoperative pulmonary complications and to identify the operability associated with severely decreased forced vital capacity (FVC) (<30%) status in flaccid neuromuscular scoliosis. The preoperative PFT, especially more than 30% FVC, is known as a critical factor for the operability of flaccid neuromuscular scoliosis. But only one study reported that patients with pre-existing respiratory failure on nocturnal noninvasive ventilation can undergo an operation for deformity correction without mortality and severe complications. A total of 74 patients (45 male and 29 female) presented with flaccid neuromuscular scoliosis. For all patients, preoperative PFTs were evaluated and subdivided into three groups (<30% FVC, 30%-50% FVC, and >50% FVC). Then postoperative pulmonary complications, pneumothorax, pneumonia, atelectasis, prolonged ventilator care in the intensive care unit (more than 72 hours), and postoperative tracheostomy were evaluated. Among these patients, 59 had muscular dystrophy; 5, spinal muscular atrophy; 2, cerebral palsy; and 8, others. The mean age at surgery was 16.8 years (range, 5-32 years). The mean preoperative Cobb angle was 54.6° (16°-135°). The overall postoperative pulmonary complication rate was 31% (23 complications in 74 patients). The less than 30% FVC group had 6 complications among 18 patients; the 30% to 50% FVC group had 7 complications among 18 patients; and the more than 50% FVC group had 10 complications among 38 patients. There were no deaths during the perioperative period. There is no statistical difference between the three groups (P = 0.6195). Patients with flaccid neuromuscular scoliosis can undergo an operation for deformity correction regardless of the severely decreased pulmonary function.Spine 02/2011; 36(21):E1391-4. · 2.08 Impact Factor -
Article: Pelvic obliquity in neuromuscular scoliosis: radiologic comparative results of single-stage posterior versus two-stage anterior and posterior approach.
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ABSTRACT: retrospective comparative study (Level III). to compare the operative results of posterior fusion and a 2-stage anterior L5-S1 fusion followed by posterior fusion in neuromuscular scoliosis patients with significant pelvic obliquity (PO). PO in neuromuscular scoliosis is common and a challenging problem that affects proper sitting balance, necessarily addressing the deformity and proper maintenance of the correction. a total of 54 patients with neuromuscular scoliosis and significant PO (>10°) were divided into 2 groups. Group 1 (n = 24) was operated on for posterior fusion and pelvic fixation. Group 2 (n = 30) included patients who were subjected to a first-stage procedure consisting of a lumbosacral junction release and fusion through a midline retroperitoneal approach and then a second-stage procedure of posterior fusion and pelvic fixation. Parameters measured included length of the follow-up, number of fusion levels, age at operation, forced vital capacity, operative time, estimated blood loss, and postoperative complications. Radiologic parameters measured before surgery, after surgery at the time of discharge, and at a final follow-up included Cobb angle, T1 translation, sitting pelvic obliquity (PO) in the frontal plane, C7 plumb line, thoracic kyphosis, lumbar lordosis, and sacral inclination angle in the sagittal plane. the correction of scoliosis was similar in both groups. The preoperative PO averaged 19.5° in Group I and 22.9° in Group II (P = 0.22), which corrected after surgery to 9.7° versus 7.4° (P = 0.23), respectively. Group II correction progressively improved significantly compared to Group I (7.0° vs. 11.6° at P = 0.046) at the latest follow-up. A 40.6% correction (mean correction = 7.9) in sitting PO in Group I compared to 70.7% correction (mean correction = 5.9°) in Group II was observed (P = 0.004). The average loss of correction of PO at the final follow-up was lesser in group II, but not statistically significant (P = 0.07). anterior fusion of the lumbosacral junction followed by posterior fusion provides superior correction and maintenance of PO in patients with neuromuscular scoliosis.Spine 01/2011; 36(2):146-52. · 2.08 Impact Factor -
Article: The risk assessment of a fall in patients with lumbar spinal stenosis.
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ABSTRACT: A prospective case control study. To investigate the risk of a fall by using functional mobility tests in patients with lumbar spinal stenosis (LSS) via a comparison with patients with knee osteoarthritis (KOA). LSS is a degenerative arthritic disease in the spine that results in decreasing function, impaired balance, and gait deficit, with increased levels of leg and back pain. This physical impairment may result in an increased risk of fall later in the disease process, as shown in KOA. However, there has been no study regarding the association between the risk of a fall and LSS. The study was an age- and weight-matched case control study consisting of two groups: one group consisting of 40 patients with LSS who were scheduled to undergo spine surgery (LSS group) and the other group consisting of 40 patients with advanced osteoarthritis in both knees, scheduled to undergo TKA on both knees (KOA group). For both groups, four functional mobility tests, such as a Six-Meter-Walk Test (SMT), Sit-to-Stand test (STS), Alternative-Step Test (AST), and Timed Up and Go Test (TUGT), were performed. There was no difference in demographic data between both groups except for body mass index. For the SMT and STS, the patients in the LSS group spent significantly more time performing these tests than the patients in the KOA. For the AST, however, patients in the KOA group presented a statistically worse performance in functional mobility, compared with the LSS group. The mean TUGT time was not statistically different between the two groups. The current study highlights that patients with symptomatic LSS have a risk of a fall comparable with the patients who had degenerative KOA based on the results of functional mobility tests (SMT, STS, AST, and TUGT).Spine 01/2011; 36(9):E588-92. · 2.08 Impact Factor -
Article: Video-assisted thoracoscopic surgery plus lumbar mini-open surgery for adolescent idiopathic scoliosis.
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ABSTRACT: The objectives of this study are to describe the outcome of adolescent idiopathic scoliosis (AIS) patients treated with Video Assisted Thoracoscopic Surgery (VATS) plus supplementary minimal incision in the lumbar region for thoracic and lumbar deformity correction and fusion. This is a case series of 13 patients treated with VATS plus lumbar mini-open surgery for AIS. A total of 13 patients requiring fusions of both the thoracic and lumbar regions were included in this study: 5 of these patients were classified as Lenke type 1A and 8 as Lenke type 5C. Fusion was performed using VATS up to T12 or L1 vertebral level. Lower levels were accessed via a small mini-incision in the lumbar area to gain access to the lumbar spine via the retroperitoneal space. All patients had a minimum follow-up of 1 year. The average number of fused vertebrae was 7.1 levels. A significant correction in the Cobb angle was obtained at the final follow-up (p = 0.001). The instrumented segmental angle in the sagittal plane was relatively well-maintained following surgery, albeit with a slight increase. Scoliosis Research Society-22 (SRS-22) scores were noted have significantly improved at the final follow-up (p < 0.05). Indications for the use of VATS may be extended from patients with localized thoracic scoliosis to those with thoracolumbar scoliosis. By utilizing a supplementary minimal incision in the lumbar region, a satisfactory deformity correction may be accomplished with minimal post-operative scarring.Yonsei medical journal 01/2011; 52(1):130-6. · 0.77 Impact Factor -
Article: Antibiotic Microbial Prophylaxis for Spinal Surgery: Comparison between 48 and 72-Hour AMP Protocols.
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ABSTRACT: This is a prospective randomized cohort study. We intended to evaluate the efficacy of a 48 hour antibiotic microbial prophylaxis (AMP) protocol as compared with a 72 hour AMP protocol. The current guideline for the prevention of surgical site infection (SSI) suggests the AMP should not exceed 24 hours after clean surgery like spinal surgery. But there exist some confusion in real clinical practice about the duration of postoperative antibiotic administration because the evidence of the guideline was not robust. The subjects were 548 patients who underwent spinal surgery at our department from April 2007 to December 2008. The patients were classified into two groups according to the prophylaxis protocol: group A, for which AMP was employed for 72 hours postoperatively and group B, for which AMP was employed for 48 hours postoperatively. Five hundred two patients out of 548 patients were followed until 6 months postoperatively. The incidence of SSI in the two groups was analyzed. The overall infection rate was 0.8%. There was no significant difference in infection rate between the two groups. The overall infection rate for the patients who underwent instrumented fusion was 0.9%. There was no significant difference in the infection rate between the patients of the two groups who underwent instrumented fusion. AMP for 48 hours is as efficient as AMP for 72 hours.Asian spine journal 12/2010; 4(2):71-6. -
Article: Comparison between Operated Muscular Dystrophy and Spinal Muscular Atrophy Patients in terms of Radiological, Pulmonary and Functional Outcomes.
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ABSTRACT: Retrospective comparative study. To study and compare the surgical outcomes of muscular dystrophy (MD) and spinal muscle atrophy (SMA). There are few reports that have evaluated and compared the surgical outcomes of MD and SMA patients. The patients (n = 35) were divided into two groups: a MD group with 24 patients and a SMA group with 11 patients. The average follow-up period was 21 months. All patients were operated for scoliosis correction using posterior instrumentation and fusion. In the immediate postoperative period, all efforts were made to reduce the pulmonary complications using non-invasive positive pressure ventilation and a coughing assist devices. The patients were evaluated by radiograph in terms of the Cobb's angle, pelvic obliquity, T1 translation, thoracic kyphosis and lumbar lordosis. The pulmonary function and self-image satisfaction were also assessed. There was a lower correction rate in the MD group (41.5%) than in the SMA group (48.3%), even though the curves were smaller in the MD group. The correction in the pelvic obliquity was significantly better in the SMA group (p = 0.03). The predicted vital capacity showed a 4% reduction in the MD group 1 year after surgery, while the SMA group showed a 10% reduction. The peak cough flow and end tidal PCO(2) did not deteriorate and were well maintained. The average score for the improvement in self-image satisfaction postoperatively was 3.96 and 4.64 for the MD and SMA groups, respectively. The total complication rate was 45.7%; 14.3% of which were respiratory-related. Surgical intervention for MD and SMA may be performed safely in patients with a very low forced vital capacity (< 30%) through aggressive preoperative and postoperative rehabilitation efforts.Asian spine journal 12/2010; 4(2):82-8. -
Article: Video-assisted thoracoscopic surgery for correction of adolescent idiopatic scoliosis: comparison of 4.5 mm versus 5.5 mm rod constructs.
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ABSTRACT: The purpose of this study is to report the comparative results of thoracoscopic correction achieved via cantilever technique using a 4.5 mm thin rod and the poly-axial reduction screw technique using a 5.5 mm thick rod in Lenke type 1 adolescent idiopathic scoliosis (AIS). Radiographic data, Scoliosis Research Society (SRS) patient-based outcome questionnaires, and operative records were reviewed for forty-nine patients undergoing surgical treatment of scoliosis. The study group was divided into a 4.5 mm thin rod group (n = 24) and a 5.5 mm thick rod group (n = 25). The radiographic parameters that were analyzed included coronal curve correction, the most caudal instrumented vertebra tilt angle correction, coronal balance, and thoracic kyphosis. The major curve was corrected from 49.8 degrees and 47.2 degrees pre-operatively to 24.5 degrees and 18.8 degrees at the final follow-up for the thin and thick rod groups, respectively (50.8% vs. 60.2% correction). There were no significant differences between the two groups in terms of kyphosis, coronal balance, or tilt angle at the time of the final follow-up. The mean number of levels fused was 6.2 in the thin rod group, compared with 5.9 levels in the thick rod group. There were no major intraoperative complications in either group. Significant correction loss was observed in the thin rod system at the final follow-up though both groups had comparable correction immediately post-operative. Therefore, the thick rod with poly axial screw system helps to maintain post-operative correction.Yonsei medical journal 09/2010; 51(5):753-60. · 0.77 Impact Factor -
Article: Vascular injury in thoracolumbar spinal surgeries and role of angiography in early diagnosis and management.
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ABSTRACT: A retrospective outcomes study. To stress on the importance of early diagnosis with the help of angiography and proper treatment of vascular injuries occurring during thoracolumbar surgeries and to report our results. Vascular injury is a rare but dangerous complication that can develop during thoracolumbar surgeries and if not treated properly then it can lead to severe complications including the death of the patient. The patients included in this study were the ones who were suspected to have a possible vascular injury after a thoracolumbar surgery. Contrast enhanced computed tomography was performed for patients having clinical signs suggesting vascular injury. Among these patients, who were suspected to have active bleeding and major vessel injury on computed tomography were further subjected to angiography. Of the 10 cases included in the study, vascular injury was identified to be arterial in origin in 8 cases and venous in 3 cases. Among the 8 cases of identified arterial injury, angiography was performed in 4 cases, of which 3 were found to have active bleeding and were subjected to immediate intervention. Of the 4 cases in which angiography was not performed, 3 of them expired at variable postoperative periods. Complications developed in total 5 cases including 3 cases of mortality, 1 case of infection, and 1 case of cauda equina syndrome. The vascular injuries during thoracolumbar spinal surgeries need immediate and aggressive treatment. In arterial injuries, we can prevent serious consequences by subjecting the patient to an angiography as early as possible followed by a therapeutic embolization. In contrast, for venous injuries if hemostasis has been confirmed, then an immediate intervention may not be always required.Journal of spinal disorders & techniques 08/2010; 23(6):418-24. · 1.21 Impact Factor -
Article: Analysis of biomechanical changes after removal of instrumentation in lumbar arthrodesis by finite element analysis.
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ABSTRACT: The purpose of this study is to investigate the change in biomechanical milieu following removal of pedicle screws in instrumented single level lumbar arthrodesis. Using a validated finite element (FE) model of the intact lumbar spine (L2-5), two scenarios of L3-4 lumbar fusion were simulated: posterolateral fusion (PLF) at L3-4 using pedicle screws (PLF with pedicle screws; WiP) and L3-4 lumbar posterolateral fusion state after removal of pedicle screws (PLF without pedicle screws; WoP). The WiP model had greater range of motion (ROM) at each adjacent segment than the WoP model. This phenomenon became pronounced at the proximal adjacent segment under flexion moment. Similarly, removal of pedicle screws (the WoP model) relieved the maximal von Mises stress at adjacent segments under 4 moments compared to the WiP model. This study demonstrated that removal of pedicle screws could decrease stiffness of fusion segments, which would reduce the disk stress of adjacent segments.Medical & Biological Engineering 07/2010; 48(7):703-9. · 1.76 Impact Factor -
Article: Association between bone mineral density and metabolic syndrome in postmenopausal Korean women.
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ABSTRACT: We investigated the relationship between bone mineral density (BMD) of the femur neck or lumbar spine and metabolic syndrome or its parameters in postmenopausal Korean women. This study included 399 postmenopausal women, for whom the BMD of their L2s-L4s and femur necks were examined in association with metabolic syndrome. Subjects with metabolic syndrome had a higher BMD of the femur neck than those without metabolic syndrome when adjusted for age (0.85 +/- 0.09 vs. 0.82 +/- 0.12 g/cm(2), p = 0.011), while there was no statistical difference at lumbar spine. When adjusted for age and BMI, high-density lipoprotein cholesterol (HDL-C) was weakly and negatively correlated with BMD of the lumbar and femur neck (r = -0.107, p = 0.033; r = -0.111, p = 0.028 respectively). Metabolic syndrome was partly associated with higher BMD in our postmenopausal Korean women. Our study also showed that HDL-C levels were negatively associated with BMD of the lumbar spine and femur neck which means that subjects with lower HDL-C levels could have higher BMD. The results of our retrospective study revealed that metabolic syndrome could be associated with higher BMD in our postmenopausal Korean women.Gynecologic and Obstetric Investigation 12/2009; 69(3):145-52. · 1.28 Impact Factor -
Article: Restoration of bone turnover rate after decompression surgery in patients with symptomatic lumbar spinal stenosis: preliminary report.
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ABSTRACT: Prospective short-term longitudinal study. To investigate changes in the bone turnover rate in patients with lumbar spinal stenosis (LSS) before and after decompression surgery. SUMMARY OF BACK GROUND DATA: Decompression surgery enables elderly patients with LSS to participate in daily activities and physical exercise by reducing or alleviating leg and back pain. However, there have been no studies to date regarding the effect of decompression surgery on bone metabolism in such patients. Twenty-three patients with spinal stenosis who were scheduled to undergo decompression surgery were enrolled in our study. Ten patients were given oral bisphosphonates after the operation (B+ group), while the remaining 13 patients did not receive oral bisphosphonate (B- group). In both groups, walking distance without rest, the Oswestry Disability Index (ODI) scores, duration of symptoms, bone formation, and resorption markers, and bone mineral density were recorded before surgery. Three months after surgery, bone turnover markers, a single trial for walking distance without rest and ODI scores were measured for both groups. Three months after the operation, the bone resorption marker u-NTx was decreased significantly for both groups. Although there was a decrease in bALP, a bone formation maker, in both groups, the change in each group was not statistical significant. Distance in a single trial walk was increased and ODI scores were decreased significantly for both groups. This study suggests that decompression surgery has a beneficial effect on bone metabolism in patients with LSS who have walking intolerance and limited physical activity.Spine 09/2009; 34(18):E635-9. · 2.08 Impact Factor -
Article: Comparison of surgical outcomes in thoracolumbar fractures operated with posterior constructs having varying fixation length with selective anterior fusion.
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ABSTRACT: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.Yonsei medical journal 09/2009; 50(4):546-54. · 0.77 Impact Factor -
Article: Multiple levels of lumbar spondylolysis - a case report -.
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ABSTRACT: We report here on an unusual case of multiple levels of asymmetric lumbar spondylolysis in a 19-year-old woman. The patient had severe low back pain of increasing intensity with lumbar instability, which was evident on the dynamic radiographs. MRI demonstrated the presence of abnormalities and the three dimensional CT scan revealed asymmetric complete spondylolysis at the left L2, L3 and L4 levels and the right L1, L2 and L3 levels. This case was treated surgically by posterior and posterolateral fusion at L2-3-4 with intersegmental fixation using pedicle screws and an auto iliac bone graft. The patient was relieved of her low back pain after the surgery.Asian spine journal 06/2009; 3(1):35-8. -
Article: A validated finite element analysis of nerve root stress in degenerative lumbar scoliosis.
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ABSTRACT: Few studies have shown the relationship between the curve pattern and nerve root symptoms in degenerative lumbar scoliosis, and its mechanism remains unclear. We developed a finite element model of two patterns of scoliotic curves (isolated lateral bending curve, lateral bending combined with rotation curve). The stress on the nerve root was calculated on both sides (right and left) of the apex vertebra. In the lateral bending curves without rotation, the compressive nerve root stress on the concave side was greater than the tensile stress on the convex side at the apex vertebra. In contrast, when the segmental rotation of the vertebrae was added to the lateral bending curve, there was significantly higher tensile stress on the convex side, and lower compressive stress on the concave side. To conclude, rotatory listhesis may be an important pathomechanism in the development of neurologic symptoms on the convex side of the curve.Medical & Biological Engineering 04/2009; 47(6):599-605. · 1.76 Impact Factor
Top Journals
Institutions
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2007–2013
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Yonsei University Hospital
Seoul, Seoul, South Korea
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2011
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Seoul National University Bundang Hospital
Seoul, Seoul, South Korea
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2009
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Yonsei University
- Department of Orthopaedic Surgery
Seoul, Seoul, South Korea
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