Dong Kyu Chin

Yonsei University Hospital, Sŏul, Seoul, South Korea

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Publications (28)49.04 Total impact

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    ABSTRACT: To investigate the molecular responses of various genes and proteins related to disc degeneration upon treatment with cytokines that affect disc-cell proliferation and phenotype in living human intervertebral discs (IVDs). Responsiveness to these cytokines according to the degree of disc degeneration was also evaluated. The disc specimens were classified into two groups: group 1 (6 patients) showed mild degeneration of IVDs and group 2 (6 patients) exhibited severe degeneration of IVDs. Gene expression was analyzed after treatment with four cytokines: recombinant human bone morphogenic protein (rhBMP-2), transforming growth factor-β (TGF-β), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α). Molecular responses were assessed after exposure of cells from the IVD specimens to these cytokines via real-time polymerase chain reaction and immunofluorescence staining. mRNA gene expression was significantly greater for aggrecan, type I collagen, type II collagen, alkaline phosphatase, osteocalcin, and Sox9 in group 1 than mRNA gene expression in group 2, when the samples were not treated with cytokines. Analysis of mRNA levels for these molecules after morphogen treatment revealed significant increases in both groups, which were much higher in group 1 than in group 2. The average number of IVD cells that were immunofluorescence stained positive for alkaline phosphatase increased after treatment with rhBMP-2 and TGF-β in group 1. The biologic responsiveness to treatment of rhBMP-2, TGF-β, TNF-α, and IL-1β in the degenerative living human IVD can be different according to the degree of degeneration of the IVD.
    Yonsei medical journal. 01/2015; 56(1):277-86.
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    ABSTRACT: COL6A1 and BMP-2 genes have been implicated in ossification of the posterior longitudinal ligament (OPLL) susceptibility in Japanese and Chinese Han populations. However, no study has yet investigated the DNA of unaffected family members of patients with OPLL. This study investigated differences in genetic polymorphisms of BMP-2 and COL6A1 between Korean patients with OPLL and their family members (with and without OPLL). A total of 321 subjects (110 patients with OPLL and 211 family members) were enrolled in the study. Associations between two single nucleotide polymorphisms (SNPs) of the BMP-2 gene (Ser37Ala and Ser87Ser) and two SNPs of COL6A1 [promoter (-572) and intron 33 (+20)] with susceptibility to OPLL of the cervical spine were investigated between the two groups (OPLL+ and OPLL-). Of the 321 subjects, 162 had cervical OPLL (50.4%; 110 patients, 52 family members). There was a familial tendency of OPLL in 34 of the 110 families (30.9%). Allele and haplotype frequencies of the four SNPs in the BMP-2 and COL6A1 genes did not differ significantly between the OPLL+ and OPLL- groups, even when excluding participants over 50 years of age. This is the first report identifying SNPs of COL6A1 and BMP-2 in Korean patients and family members with OPLL. Although allele and haplotype frequencies were similar with those of a previous study in Japanese and Chinese patients, unaffected family members also showed similar rates of these SNPs in the present study. These results suggest that these SNPs may not directly influence the expression of OPLL.
    Genetics and molecular research: GMR 01/2014; 13(1):2240-2247. · 0.99 Impact Factor
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    ABSTRACT: Minimally invasive surgery with a transforaminal lumbar interbody fusion (MIS TLIF) is an important minimally invasive fusion technique for the lumbar spine. Lumbar spine reoperation is challenging and is thought to have greater complication risks. The purpose of this study was to compare MIS TLIF with unilateral screw fixation perioperative results between primary and revision surgeries. This was a prospective study that included 46 patients who underwent MIS TLIF with unilateral pedicle screw. The patients were divided into two groups, primary and revision MIS TLIF, to compare perioperative results and complications. The two groups were similar in age, sex, and level of operation, and were not significantly different in the length of follow-up or clinical results. Although dural tears were more common with the revision group (primary 1; revision 4), operation time, blood loss, total perioperative complication, and fusion rates were not significantly different between the two groups. Both groups showed substantial improvements in VAS and ODI scores one year after surgical treatment. Revision MIS TLIF performed by an experienced surgeon does not necessarily increase the risk of perioperative complication compared with primary surgery. MIS TLIF with unilateral pedicle screw fixation is a valuable option for revision lumbar surgery.
    BioMed Research International 01/2014; 2014:919248. · 2.71 Impact Factor
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    ABSTRACT: Surgeon spine angle during surgery was studied ergonomically and the kinematics of the surgeon's spine was related with musculoskeletal fatigue and pain. Spine angles varied depending on operation table height and visualization method, and in a previous paper we showed that the use of a loupe and a table height at the midpoint between the umbilicus and the sternum are optimal for reducing musculoskeletal loading. However, no studies have previously included a microscope as a possible visualization method. The objective of this study is to assess differences in surgeon spine angles depending on operating table height and visualization method, including microscope. We enrolled 18 experienced spine surgeons for this study, who each performed a discectomy using a spine surgery simulator. Three different methods were used to visualize the surgical field (naked eye, loupe, microscope) and three different operating table heights (anterior superior iliac spine, umbilicus, the midpoint between the umbilicus and the sternum) were studied. Whole spine angles were compared for three different views during the discectomy simulation: midline, ipsilateral, and contralateral. A 16-camera optoelectronic motion analysis system was used, and 16 markers were placed from the head to the pelvis. Lumbar lordosis, thoracic kyphosis, cervical lordosis, and occipital angle were compared between the different operating table heights and visualization methods as well as a natural standing position. Whole spine angles differed significantly depending on visualization method. All parameters were closer to natural standing values when discectomy was performed with a microscope, and there were no differences between the naked eye and the loupe. Whole spine angles were also found to differ from the natural standing position depending on operating table height, and became closer to natural standing position values as the operating table height increased, independent of the visualization method. When using a microscope, lumbar lordosis, thoracic kyphosis, and cervical lordosis showed no differences according to table heights above the umbilicus. This study suggests that the use of a microscope and a table height above the umbilicus are optimal for reducing surgeon musculoskeletal fatigue.
    European Spine Journal 12/2013; · 2.47 Impact Factor
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    ABSTRACT: Purpose: All structures of the spine, including the spinal canal, change continuously with age. The purpose of this study was to determine how the spinal canal of the lumbar spine changes with age. The L4/5 is the most common site of spinal stenosis and has the largest flexion-extension motion, whereas the T5/6 has the least motion. Therefore, we measured the spinal canal diameter and vertebral body height at T5, T6, L4, and L5 with age. Materials and Methods: This was a retrospective study of aged 40 to 77 years. We reviewed whole spine sagittal MRIs of 370 patients with lumbar spinal stenosis (LSS) (Group 2) and 166 herniated cervical disc (HCD) (Group 1). Each group was divided into four age groups, and demographic parameters (age, gender, height, weight, BMI), the mid-spinal canal diameter, and mid-vertebrae height at T5, T6, L4, L5 were compared. Within- and between-group comparisons were made to evaluate changes by age and correlations were carried out to evaluate the relationships between all parameters. Results: Height, weight, and all radiologic parameters were significantly lower in Group 2 than Group 1. Group 1 did not show any differences, when based on age, but in Group 2, height, weight, and T6, L4, and L5 height were significantly decreased in patients in their 70's than patients in their 40's, except for spinal canal diameter. Age was associated with all parameters except spinal canal diameter. Conclusion: Vertebral height decreased with age, but spinal canal diameter did not change in patients with either LSS or HCD. Mid-spinal canal diameter was not affected by aging.
    Yonsei medical journal 11/2013; 54(6):1498-504. · 0.77 Impact Factor
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    ABSTRACT: Object Clinical results for unilateral pedicle screw fixation after lumbar interbody fusion have been reported to be as good as those for bilateral instrumentation. However, no studies have directly compared unilateral and bilateral percutaneous pedicle screw fixation after minimally invasive surgery (MIS) for transforaminal lumbar interbody fusion (TLIF). The purpose of this study was to determine whether unilateral percutaneous pedicle screw fixation is comparable with bilateral percutaneous pedicle screw fixation in 1-segment MIS TLIF. Methods This was a prospective randomized study of 53 patients who underwent unilateral or bilateral percutaneous pedicle screw fixation after MIS TLIF for 1-segment lumbar degenerative disc disease. Twenty-six patients were assigned to a unilateral percutaneous pedicle screw fixation group and 27 patients were assigned to a bilateral percutaneous pedicle screw fixation group. Operative time, blood loss, clinical outcomes (that is, Oswestry Disability Index [ODI] and visual analog scale [VAS] scores), complication rates, and fusion rates were assessed using CT scanning 2 years after surgical treatment. Results The 2 groups were similar in age, sex, preoperative diagnosis, and operated level, and they did not differ significantly in the length of follow-up (27.5 [Group 1] vs 28.9 [Group 2] months) or clinical results. Both groups showed substantial improvements in VAS and ODI scores 2 years after surgical treatment. The groups differed significantly in operative time (unilateral 84.2 minutes; bilateral 137.6 minutes), blood loss (unilateral 92.7 ml; bilateral, 232.0 ml), fusion rate (unilateral 84.6%; bilateral 96.3%), and postoperative scoliotic change (unilateral 23.1%; bilateral 3.7%). Conclusions Unilateral and bilateral screw fixation after MIS TLIF produced similar clinical results. Although perioperative results were better with unilateral screw fixation, the long-term results were better with bilateral screw fixation, suggesting bilateral screw fixation is a better choice after MIS TLIF.
    Neurosurgical FOCUS 08/2013; 35(2):E11. · 2.49 Impact Factor
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    ABSTRACT: PURPOSE: It is well known that arthrodesis is associated with adjacent segment degeneration (ASD). However, previous studies were performed with simple radiography or CT. MRI is most sensitive in assessing the degenerative change of a disc, and this is the first study about ASD by radiography, CT and MRI. We sought to factors related to ASD at cervical spine by an MRI and CT, after anterior cervical spine surgery. MATERIALS AND METHODS: This is a retrospective cross-sectional study of cervical disc herniation. Patients of cervical disc herniation with only radiculopathy were treated with either arthroplasty (22 patients) or ACDF with cage alone (21 patients). These patients were required to undergo MRI, CT and radiography preoperatively, as well as radiography follow-up for 3 months and 1 year, and we conducted a cross-sectional study by MRI, CT and radiography including clinical evaluations 5 years after. Clinical outcomes were assessed using VAS and NDI. The fusion rate and ASD rate, and radiologic parameters (cervical lordosis, operated segmental height, C2-7 ROM, operated segmental ROM, upper segmental ROM and lower segmental ROM) were measured. RESULTS: The study groups were demographically similar, and substantial improvements in VAS (for arm) and NDI (for neck) scores were noted, and there were no significant differences between groups. Fusion rates were 95.2 % in the fusion group and 4.5 % in the arthroplasty group. ASD rates of the fusion and arthroplasty groups were 42.9 and 50 %, respectively. Among the radiologic parameters, operated segmental height and operated segmental ROM significantly decreased, while the upper segmental ROM significantly increased in the fusion group. In a comparative study between patients with ASD and without ASD, the clinical results were found to be similar, although preexisting ASD and other segment degeneration were significantly higher in the ASD group. C2-7 ROM was significantly decreased in ASD group, and other radiologic parameters have no significant differences between groups. CONCLUSION: The ASD rate of 46.5 % after ACDF or arthroplasty, and arthroplasty did not significantly lower the rate of ASD. ASD occurred in patients who had preexisting ASD and in patients who also had other segment degeneration. ASD may be associated with a natural history of cervical spondylosis rather than arthrodesis.
    European Spine Journal 12/2012; · 2.47 Impact Factor
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    ABSTRACT: PURPOSE: The ergonomic problems for surgeons during spine surgery are an awkward body posture, repetitive movements, increased muscle activity, an overflexed spine, and a protracted time in a standing posture. The authors analyzed whole spine angles during discectomy. The objective of this study is to assess differences in surgeon whole spines angles according to operating table height and the methods used to visualize surgical field. MATERIALS AND METHODS: A cohort of 12 experienced spine surgeons was enrolled. Twelve experienced spine surgeons performed discectomy using a spine surgery simulator. Three different methods were used to visualize the surgical field (naked eye, loupe, and out of loupe) and three different operating table heights. Whole spine angles were compared for three different views during discectomy simulation; midline, ipsilateral, and contralateral. A 16-camera optoelectronic motion analysis system was used, and 16 markers were placed from head to pelvis. Lumbar lordosis, thoracic kyphosis, cervical lordosis, and occipital angle were compared at the different operating table heights, while using the three visualization methods, with natural standing position. RESULTS: Whole spine angles were significantly different for visualization methods. Lumbar lordosis, cervical lordosis, and occipital angle were closer to natural standing values when discectomy was performed with a loupe, but most measures differed from natural standing values when performed out of loupe. Thoracic kyphosis was also similar to the natural standing position during discectomy using a loupe, but differed from the natural standing position when performed with naked eye. Whole spine angles were also found to differ from the natural standing position according to operating table height, and became closer to natural standing position values as operating table height increased, when simulation was conducted with loupe. CONCLUSION: This study suggests that loupe use and a table height midpoint between the umbilicus and sternum are optimal for reducing surgeon musculoskeletal fatigue.
    European Spine Journal 07/2012; · 2.47 Impact Factor
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    ABSTRACT: We investigated the importance, risk factors, and clinical course of the radiolucent "halo" phenomenon around bone cement following vertebral augmentation for osteoporotic compression fracture. Preoperative osteonecrosis and a lump cement pattern were the most important risk factors for the peri-cement halo phenomenon, and it was associated with vertebral recollapse. We observed a newly developed radiolucent area around the bone cement following vertebral augmentation for osteoporotic compression fractures. Here, we describe the importance of the peri-cement halo phenomenon, as well as any associated risk factors and long-term sequelae. In total, 175 patients (202 treated vertebrae) were enrolled in this study. The treated vertebrae were subdivided into two groups: Group A (with halo, n = 32) and Group B (without halo, n = 170), and the groups were compared with respect to multiple preoperative (age, sex, BMD, preoperative osteonecrosis) and perioperative factors (operative approach: vertebroplasty or kyphoplasty; cement distribution pattern; cement leakage; cement volume), and postoperative results (VAS score, recollapse). Logistic regression analysis was used to evaluate the relationship between the incidence of the peri-cement halo and all of the parameters described above. Rates of osteonecrosis were also significantly higher in Group A than in Group B (62.5% vs. 31.2%, p < 0.05), and kyphoplasty (KP) was performed more frequently in Group A (43.8% vs. 17.6%, p < 0.05). Lump cement (93.8% vs. 30.6%, p < 0.05) and recollapse (78.1% vs. 24.7%, p < 0.05) were also more common among individuals in Group A. Logistic regression analysis also showed that preoperative osteonecrosis (OR = 3.679; 95% CI = 1.677-8.073; p = 0.001), KP (OR = 3.630; 95% CI = 1.628-8.095; p = 0.002), lump pattern (OR = 13.870; 95% CI = 2.907-66.188; p = 0.001), and vertebral recollapse (OR = 5.356; 95% CI = 1.897-15.122; p = 0.002) were significantly associated with peri-cement halo. The peri-cement halo was found to be associated with vertebral recollapse, this sign likely represents a poor prognostic factor after vertebral augmentation for osteoporotic compression fractures.
    Osteoporosis International 01/2012; 23(10):2559-65. · 4.04 Impact Factor
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    ABSTRACT: A retrospective review of clinical and radiological parameters. To assess for at least 2 years the radiological and clinical outcomes of patients who underwent polymethylmethacrylate (PMMA) vertebroplasty to treat osteoporotic vertebral compression fractures with avascular necrosis. Recently, osteoporotic vertebral compression fractures with avascular osteonecrosis have been treated with percutaneous vertebroplasty. However, there have been no previous multiyear, clinical, and radiological studies of the results of vertebroplasty in the vertebral body with noninfected avascular osteonecrosis. Thirty patients were followed for at least 2 years after vertebroplasty. We retrospectively reviewed several parameters, including visual analogue scale score, Oswestry Disability Index, compression ratio, kyphotic angle, injection pattern of PMMA (interdigitation and solid mass), and morphological changes of the PMMA-cemented vertebral bodies. RESULTS.: The vertebral height and kyphotic angle were significantly corrected after vertebroplasty. However, the restored vertebral height recollapsed (P < 0.05), and the kyphotic angle became aggravated (P < 0.05) during the 2 years or longer of postoperative follow-up. Visual analogue scale and Oswestry Disability Index were significantly decreased at postoperative day 1. However, visual analogue scale and Oswestry Disability Index were significantly increased at 24 months postoperatively. There were 4 kinds of morphological changes of the injected PMMA-cemented vertebral body, including heterotopic ossification, fusion with the adjacent vertebral body, bone cement fragmentation and migration, and development of a radiolucent line around the PMMA mass in the vertebral body. After vertebroplasty, the compression and kyphosis of avascular necrotic vertebral bodies progressed continuously for 2 years or longer. Vertebroplasty may not provide sufficient stability. Therefore, we strongly recommend that strict observation and follow-up be used after vertebroplasty.
    Spine 10/2011; 37(7):E423-9. · 2.16 Impact Factor
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    Jee Hee Kim, Young Mok Park, Dong Kyu Chin
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    ABSTRACT: Idiopathic hypertrophic spinal pachymeningitis (IHSP) is a rare inflammatory disease characterized by hypertrophic inflammation of the dura mater and various clinical courses that are from myelopathy. Although many associated diseases have been suggested, the etiology of IHSP is not well understood. The ideal treatment is controversial. In the first case, a 55-year-old woman presented back pain, progressive paraparesis, both leg numbness, and voiding difficulty. Initial magnetic resonance imaging (MRI) demonstrated an anterior epidural mass lesion involving from C6 to mid-thoracic spine area with low signal intensity on T1 and T2 weighted images. We performed decompressive laminectomy and lesional biopsy. After operation, she was subsequently treated with steroid and could walk unaided. In the second case, a 45-year-old woman presented with fever and quadriplegia after a spine fusion operation due to lumbar spinal stenosis and degenerative herniated lumbar disc. Initial MRI showed anterior and posterior epidural mass lesion from foramen magnum to C4 level. She underwent decompressive laminectomy and durotomy followed by steroid therapy. However, her conditions deteriorated gradually and medical complications occurred. In our cases, etiology was not found despite through investigations. Initial MRI showed dural thickening with mixed signal intensity on T1- and T2-weighted images. Pathologic examination revealed chronic nonspecific inflammation in both patients. Although one patient developed several complications, the other showed slow improvement of neurological symptoms with decompressive surgery and steroid therapy. In case of chronic compressive myelopathy due to the dural hypertrophic change, decompressive surgery such as laminectomy or laminoplasty may be helpful as well as postoperative steroid therapy.
    Journal of Korean Neurosurgical Society 10/2011; 50(4):392-5. · 0.60 Impact Factor
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    ABSTRACT: Retrospective analysis to compare the effect and complication of epidural patient-controlled analgesia (epidural PCA) with intravenous patient-controlled analgesia (IV PCA) for the treatment of the post-operative pain after posterior lumbar instrumented fusion. Sixty patients who underwent posterior lumbar instrumented fusion for degenerative lumbar disease at our institution from September 2007 to January 2008 were enrolled in this study. Out of sixty patients, thirty patients received IV PCA group and thirty patients received epidural PCA group. The pain scale was measured by the visual analogue scale (VAS) score. There were no significant difference between IV PCA group and epidural PCA group on the PCA related complications (p=0.7168). Ten patients in IV PCA group and six patients in epidural PCA group showed PCA related complications. Also, there were no significant differences in reduction of VAS score between two groups on postoperative 2 hours (p=0.9618) and 6 hours (p=0.0744). However, postoperative 12 hours, 24 hours and 48 hours showed the significant differences as mean of reduction of VAS score (p=0.0069, 0.0165, 0.0058 respectively). The epidural PCA is more effective method to control the post-operative pain than IV PCA after 12 hours of spinal fusion operation. However, during the first twelve hours after operation, there were no differences between IV PCA and epidural PCA.
    Journal of Korean Neurosurgical Society 09/2011; 50(3):205-8. · 0.60 Impact Factor
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    ABSTRACT: We prospectively investigated whether high intramedullary SI and contrast [gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA)] enhancement in magnetic resonance imaging (MRI) are associated with postoperative prognosis in cervical compressive myelopathy (CCM) patients. Seventy-four patients with ventral cord compression at one or two levels underwent anterior cervical discectomy and fusion (ACDF) for CCM between March 2006 and June 2009. The mean follow-up period was 39.7 months (range, 12.7-55.7 months). The cervical cord compression ratio and clinical outcomes were measured using Japanese Orthopedic Association (JOA) scores for cervical myelopathy. Patients were classified into three groups based on the SI change in T2WI, T1-weighted images (T1WI), and contrast (Gd-DTPA) enhancement. The mean preoperative and postoperative JOA scores were 10.5 ± 2.9 and 15.0 ± 2.1 (P < 0.05), respectively. The mean recovery ratio of the JOA score was 70.9 ± 20.2%. There were statistically significant differences in postoperative JOA and recovery ratio among three groups. However, post-surgical neurological outcomes were not associated with age, symptom duration, preoperative JOA, and cord compression. We found that intramedullary SI change is a poor prognostic factor and the intramedullary contrast (Gd-DTPA) enhancement on preoperative MRI should be viewed as the worst predictor of surgical outcomes in cervical myelopathy. Contrast (Gd-DTPA) enhancement and postoperative MRI are useful for identifying the prognosis of patients with poor neurological recovery.
    European Spine Journal 07/2011; 20(12):2267-74. · 2.47 Impact Factor
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    ABSTRACT: 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). 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. 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. 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.
    Yonsei medical journal 10/2009; 50(5):689-96. · 0.77 Impact Factor
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    ABSTRACT: The purpose of this study was to establish new fusion criteria to complement existing Brantigan-Steffee fusion criteria. The primary purpose of intervertebral cage placement is to create a proper biomechanical environment through successful fusion. The existence of a traction spur is an essential predictable radiologic factor which shows that there is instability of a fusion segment. We studied the relationship between the existence of a traction spur and fusion after a posterior lumbar interbody fusion (PLIF) procedure. This study was conducted using retrospective radiological findings from patients who underwent a PLIF procedure with the use of a cage without posterior fixation between 1993 and 1997 at a single institution. We enrolled 183 patients who were followed for a minimum of five years after the procedure, and used the Brantigan-Steffee classification to confirm the fusion. These criteria include a denser and more mature bone fusion area than originally achieved during surgery, no interspace between the cage and the vertebral body, and mature bony trabeculae bridging the fusion area. We also confirmed the existence of traction spurs on fusion segments and non-fusion segments. The PLIF procedure was done on a total of 251 segments in 183 patients (71 men and 112 women). The average follow-up period was 80.4 +/- 12.7 months. The mean age at the time of surgery was 48.3 +/- 11.3 years (range, 25 to 84 years). Among the 251 segments, 213 segments (84.9%) were fused after five years. The remaining 38 segments (15.1%) were not fused. An analysis of the 38 segments that were not fused found traction spur formation in 20 of those segments (52.6%). No segments had traction spur formation with fusion. A new parameter should be added to the fusion criteria. These criteria should be referred to as 'no traction spur formation' and should be used to confirm fusion after a PLIF procedure.
    Journal of Korean Neurosurgical Society 10/2009; 46(4):328-32. · 0.60 Impact Factor
  • Keun Su Kim, Dong Kyu Chin, Jeong Yoon Park
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    ABSTRACT: The purpose of this study was to evaluate the pattern of disc herniation and to investigate the associated symptoms in cases of isthmic spondylolisthesis. It is well known that the pathogenesis of degenerative spondylolisthesis associates with disc degeneration, followed by facet laxity and ligamentum flavum hypertrophy, which result in severe spinal canal stenosis. But isthmic spondylolisthesis is known to have a different pathogenesis. In isthmic spondylolisthesis, pseudodisc bulging is easily identified, and canal stenosis is comparatively rare. Therefore, we propose that isthmic spondylolisthesis has a different pattern of disc herniation from degenerative spondylolisthesis. We studied the type, incidence of disc herniation and clinical symptoms related to isthmic spondylolisthesis. This study included 132 patients with isthmic spondylolisthesis who had undergone an operation in the last 4 years. Among them, 120 patients were retrospectively reviewed. The mean age was 49.6 years, and the sex ratio was 1 to 1.93 (male to female). The disc herniation type was identified according to the classification of Bonneville. There were 78 patients (65%) with L4 to L5 spondylolisthesis and 42 patients (35%) with L5 to S1 spondylolisthesis. Eighty-two patients (68.3%) had only pseudodisc bulging without disc herniation, and 38 patients (31.7%) had pseudodisc bulging with disc herniation. Among the 38 patients with disc herniation, there were: medial type: 1 patient (2.6%), medial + posterolateral type: 1 patient (2.6%), posterolateral + foraminal type: 2 patients (5.3%), foraminal type: 7 patients (18.4%), foraminal + extraforaminal type: 25 patients (65.8%) and extraforaminal type: 2 patients (5.8%). Overall extreme lateral disc herniation (foraminal, extraforaminal) was seen in 36 patients, which was 30% of the total isthmic spondylolisthesis cases. In 26 out of 36 patients (72.2%), the dermatome was matched to the exact location of the extreme lateral disc herniation. In all cases, the extreme lateral disc herniation migrated upward slightly, about one slice (2 mm) according to thin-cut CT. As expected, pseudodisc bulging without disc herniation was the most common type in isthmic spondylolisthesis. However, in cases of disc herniation, extreme lateral disc herniation occasionally occurs; therefore, every isthmic spondylolisthesis patient should be examined carefully for extreme lateral disc herniation with thin-cut axial CT or MRI, especially when the patients complain of lateralizing symptom.
    Acta Neurochirurgica 07/2009; 151(11):1445-50. · 1.55 Impact Factor
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    ABSTRACT: 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). 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. 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). 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.
    Journal of Korean Neurosurgical Society 05/2009; 45(4):213-8. · 0.56 Impact Factor
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    ABSTRACT: The authors conducted a retrospective observational study using kinetic MR imaging to investigate the relationship between instability, abnormal sagittal segmental motion, and radiographic variables consisting of intervertebral disc degeneration, facet joint osteoarthritis (FJO), degeneration of the interspinous ligaments, ligamentum flavum hypertrophy (LFH), and the status of the paraspinal muscles. Abnormal segmental motion, defined as > 10 degrees angulation and > 3 mm of translation in the sagittal plane, was investigated in 1575 functional spine units (315 patients) in flexion, neutral, and extension postures using kinetic MR imaging. Each segment was assessed based on the extent of disc degeneration (Grades I-V), FJO (Grades 1-4), interspinous ligament degeneration (Grades 1-4), presence of LFH, and paraspinal muscle fatty infiltration observed on kinetic MR imaging. These factors are often noted in patients with degenerative disease, and there are grading systems to describe these changes. For the first time, the authors attempted to address the relationship between these radiographic observations and the effects on the motion and instability of the functional spine unit. The prevalence of abnormal translational motion was significantly higher in patients with Grade IV degenerative discs and Grade 3 arthritic facet joints (p < 0.05). In patients with advanced disc degeneration and FJO, there was a lesser amount of motion in both segmental translation and angulation when compared with lower grades of degeneration, and this difference was statistically significant for angular motion (p < 0.05). Patients with advanced degenerative Grade 4 facet joint arthritis had a significantly lower percentage of abnormal angular motion compared to patients with normal facet joints (p < 0.001). The presence of LFH was strongly associated with abnormal translational and angular motion. Grade 4 interspinous ligament degeneration and the presence of paraspinal muscle fatty infiltration were both significantly associated with excessive abnormal angular motion (p < 0.05). This kinetic MR imaging analysis showed that the lumbar functional unit with more disc degeneration, FJO, and LFH had abnormal sagittal plane translation and angulation. These findings suggest that abnormal segmental motion noted on kinetic MR images is closely associated with disc degeneration, FJO, and the pathological characteristics of interspinous ligaments, ligamentum flavum, and paraspinal muscles. Kinetic MR imaging in patients with mechanical back pain may prove a valuable source of information about the stability of the functional spine unit by measuring abnormal segmental motion and grading of radiographic parameters simultaneously.
    Journal of Neurosurgery Spine 05/2009; 10(4):357-65. · 1.98 Impact Factor
  • Jun Jae Shin, Dong Kyu Chin, Young Sul Yoon
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    ABSTRACT: Vertebroplasty is a minimally invasive surgical procedure which involves injecting polymethylmethacrylate into the compressed vertebral body. At present the indications include the treatment of osteoporotic compression fractures, vertebral myeloma, and metastases. The value of vertebroplasty in osteoporotic compression fracture has been discussed comprehensively. The surgical operation for burst fractures without neurological deficit remains controversial. Some authors have asserted that vertebroplasty is contraindicated in patients with burst fracture. However, we performed the procedure, after considering the patents general condition, to reduce surgical risks and the duration of immobilisation. The purpose of this study is to investigate clinical outcomes, kyphosis correction, wedge angle, and height restoration of thoraco-lumbar osteoporotic burst fractures treated by percutaneous vertebroplasty. Twenty-five patients with osteoporotic burst fracture were treated with postural reduction followed by vertebroplasty. We measured the kyphosis, wedge angle, spinal canal compromise and the height of the fractured vertebral body initially, after postural reduction, and after vertebroplasty. The average height of the collapsed vertebral bodies was 24.8% of the original height. Average kyphosis angle was 19.4 degrees and average wedge angle was 19.8 degrees at first. Mean canal encroachment was initially 25.1%. Kyphosis angle, wedge angle, and anterior, middle, and posterior height improved significantly after the procedure. The mean amelioration of the spinal canal encroachment after vertebroplasty was 23.3%. The average increase in anterior vertebral body height was 7.5 mm, central was 5.8 mm, and posterior was 0.9 mm. The mean reduction in kyphosis angle was 6.8 degrees and the mean reduction in wedge angle was 9.7 degrees . Although vertebroplasty has been considered as contraindicated in thoraco-lumbar burst fractures, we successfully used the procedure as a safe treatment in patients with osteoporotic burst fracture without neurologic deficit. This method could eliminate the need for and risks of major spinal surgery. We would like to offer it as a relatively safe and effective methods of management in thoraco-lumbar burst fractures.
    Acta Neurochirurgica 03/2009; 151(2):141-8. · 1.55 Impact Factor
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    Jeong Yoon Park, Dong Kyu Chin, Yong Eun Cho
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    ABSTRACT: Many biomechanical and clinical studies on adjacent segment degeneration (ASD) have addressed cranial segment. No study has been conducted on caudal segment degeneration after upper segment multiple lumbar fusions. This is a retrospective investigation of the L5-S1 segment after spinal fusion at and above L4-5, which was undertaken to analyze the rate of caudal ASD at L5-S1 after spinal fusion on and above L4-5 and to determine that factors that might have influenced it. The authors included 67 patients with L4-5, L3-5, or L2-5 posterior fusions. Among these patients, 28 underwent L4-5 fusion, 23 L3-5, and 16 L2-5 fusions. Pre- and postoperative radiographs were analyzed to assess degenerative changes at L5-S1. Also, clinical results after fusion surgery were analyzed. Among the 67 patients, 3 had pseudoarthrosis, and 35 had no evidence of ASD, cranially and caudally. Thirteen patients (19.4%) showed caudal ASD, 23 (34.3%) cranial ASD, and 4 (6.0%) both cranial and caudal ASD. Correlation analysis for caudal ASD at L5-S1 showed that pre-existing L5-S1 degeneration was most strongly correlated. In addition, numbers of fusion segments and age were also found to be correlated. Clinical outcome was not correlated with caudal ASD at L5-S1. If caudal and cranial ASD are considered, the overall occurrence rate of ASD increases to 50%. The incidence rate of caudal ASD at L5-S1 was significantly lower than that of cranial ASD. Furthermore, the occurrence of caudal ASD was found to be significantly correlated with pre-existing disc degeneration.
    Journal of Korean Neurosurgical Society 03/2009; 45(2):81-4. · 0.56 Impact Factor

Publication Stats

157 Citations
49.04 Total Impact Points

Institutions

  • 2007–2014
    • Yonsei University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2008–2009
    • National Health Insurance Corporation Ilsan Hospital
      Sŏul, Seoul, South Korea
  • 2006–2009
    • Yonsei University
      • • Department of Neurosurgery
      • • College of Medicine
      Seoul, Seoul, South Korea