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This study aimed to evaluate the permissible joint-line obliquity (JLO) based on radiologic and clinical outcomes with midterm follow-up after medial open-wedge high tibial osteotomy (MOWHTO).Patients who had undergone MOWHTO from March 2014 to May 2016 were retrospectively evaluated. They were divided into 4 groups based on JLO as represented by postoperative medial proximal tibial angle (MPTA). Radiologic parameters including MPTA, joint-line orientation angle (JLOA), joint-line convergence angle (JLCA), posterior tibial slope, weightbearing line ratio (WBLR), and coronal translation were analyzed. Clinical outcomes were evaluated with American Knee Society Score (AKSS), Western Ontario and McMaster University Index, and short-form 36 health survey (SF-36). The changes between preoperation and final follow-up in JLOA and MPTA were defined as ΔJLOA and ΔMPTA.A total of 135 knees were finally included (MPTA ≤90.32° as group I; 90.33° to 92.62° as group II; 92.74° to 95.22° as group III; and ≥95.23° as group IV). The last follow-up MPTA, JLOA, and JLCA values were different between the groups (P.001, P.001, and P = .015, respectively). WBLR and JLOA positively correlated with MPTA; however, WBLR showed an abrupt increase at MPTA96.5°, and the JLOA distribution tended to be greater than the regression line at MPTA96°. Moreover, ΔJLOA was not as large as ΔMPTA. The percentage of patients attaining a minimal clinically important difference was significantly lower in the AKSS-functional score and SF-36 physical component summary in group IV (P = .008 and 0.021, respectively).The JLOA did not change as much as the MPTA, but an MPTA95.2° abruptly increased the JLOA and valgus overcorrection after MOWHTO. Poor clinical outcomes were more evident in excessive MPTA (95.2°) than in mildly undercorrected or properly corrected MPTA (95.2°).III, retrospective cohort study.

OBJECTIVE Combined anterior-posterior (AP) surgery is considered the gold standard for surgical treatment of Scheuermann kyphosis. There are trends toward posterior-only (PO) surgery for correcting this deformity because of the availability of multisegmental compression instruments and posterior shortening osteotomy. To date, surgical strategies for Scheuermann kyphosis remain controversial. The purpose of this study was to compare various surgical approaches for the treatment of Scheuermann kyphosis, including radiological correction and intraoperative outcomes, using a systematic review and meta-analysis. METHODS A comprehensive database search of PubMed, EMBASE, Web of Science, and Cochrane Library was performed to identify studies concerning Scheuermann kyphosis. The inclusion criteria were direct comparisons between AP and PO surgeries for Scheuermann kyphosis and assessment of the angle of thoracic kyphosis preoperatively and postoperatively. The authors used the principles of a cumulative meta-analysis by updating the pooled estimate of the treatment effect. RESULTS Data from 13 studies involving 1147 participants (542 patients in the AP group and 605 patients in the PO group) were included. The average age was 18.2 years for the AP and 17.9 years for the PO group. The overall mean difference of changes in thoracic kyphosis angles between the AP and PO surgeries was 0.23° (95% CI −2.24° to 2.71°). In studies in which posterior shortening osteotomies were not performed, PO surgery resulted in a significantly low degree of correction of thoracic kyphosis, with a mean difference of 5.59° (95% CI 0.34°–10.83°). Studies in which osteotomies were performed revealed that the angle of correction for PO surgery was comparable to that of AP surgery. Regardless of fixation methods, PO surgical approaches achieved comparable angles. CONCLUSIONS PO surgery using posterior osteotomies can achieve correction of Scheuermann kyphosis as successfully as AP surgery does. Reflecting the advancement of surgical technology, large prospective studies are necessary to identify the proper treatments for Scheuermann kyphosis.

Using a machine learning method, this study aimed to identify unique causal networks of genes associated with bone, brain, and lung metastasis of breast cancer. Bayesian network analysis identified differentially expressed genes in primary breast cancer tissues, in bone, brain, and lung breast cancer metastatic tissues, and the clinicopathological features of patients obtained from the Gene Expression Omnibus microarray datasets. We evaluated the causal Bayesian networks of breast metastasis to distant sites (bone, brain, or lung) by (i) measuring how well the structures of each specific type of breast cancer metastasis fit the data, (ii) comparing the structures with known experimental evidence, and (iii) reporting predictive capabilities of the structures. We report for the first time that the molecular gene signatures are specific to the different types of breast cancer metastasis. Several genes, including CHPF, ARC, ANGPTL4, NR2E1, SH2D1A, CTSW, POLR2J4, SPTLC1, ILK, ALDH3B1, PDE6A, SCTR, ADM, HEY1, KCNF1, and UVRAG, were found to be predictors of the risk for site-specific metastasis of breast cancer. Expression of POLR2JA, SPTLC1, ILK, ALDH3B1, and the estrogen receptor was significantly associated with breast cancer bone metastasis. Expression of PDE6A and NR2E1 was causally linked to breast cancer brain metastasis. Expression of HEY1, KCNF1, UVRAG, and the estrogen and progesterone receptors was strongly associated with breast cancer lung metastasis. The causal Bayesian network structures of these genes identify potential interactions among the genes in distant metastases of breast cancer, including to the bone, brain, and lung, and may serve as target candidates for treatment of breast cancer metastasis.

Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium that causes infections in different parts of the body and causes skin and soft tissue infections (SSTI). The present study examined the antimicrobial resistance patterns and molecular epidemiological characteristics of MRSA isolated from nasal swabs in clinical patients. SCCmec type of MRSA isolates from clinical patients were analyzed: 24 cases were SCCmec type-II; two cases were type-II/IVa; one case was type-II/V; one case was type-IVa; 11 cases were not-typeable. The mec complex type of MRSA isolates from clinical patients were analyzed: 29 cases were mec complex type A, and 10 cases were not-typeable, but type B was not found in the present study. In conclusion, SCCmec type-II and mec complex type A were the most dominant MRSA subtypes among the MRSA isolates from a nasal swab of patients, and the results were similar to other studies on hospital-acquired MRSA (HA-MRSA). These results can not only provide basic data for hospital infection management but also be a good guideline for MRSA infections in the Republic of Korea.

Objective The demand for treating degenerative lumbar spinal disease has been increasing, leading to increased utilization of medical resources. Thus, we need to understand how the budget of insurance is currently used. The objective of the present study is to overview the utilization of the National Health Insurance Service (NHIS) by providing the direct insured cost between patients receiving surgery and patients receiving nonsurgical treatment for degenerative lumbar disease. Methods The NHIS-National Sample Cohort was utilized to select patients with lumbar disc herniation, spinal stenosis, spondylolisthesis or spondylolysis. A matched cohort study design was used to show direct medical costs of surgery (n = 2,698) and nonsurgical (n = 2,698) cohorts. Non-surgical treatment included medication, physiotherapy, injection, and chiropractic. The monthly costs of the surgery cohort and nonsurgical cohort were presented at initial treatment, posttreatment 1, 3, 6, 9, and 12 months and yearly thereafter for 10 years. Results The characteristics and matching factors were well-balanced between the matched cohorts. Overall, surgery cohort spent $50.84/patient/month, while the nonsurgical cohort spent $29.34/patient/month (p Conclusion Surgical treatment initially led to more government reimbursement than nonsurgical treatment, but the charges during follow-up period were not different. The results of the present study should be interpreted in light of the costs of medical services, indirect costs, societal cost, quality of life and societal willingness to pay in each country. The monetary figures are implied to be actual economic costs but those in the reimbursement system instead reflect reimbursement charges from the government.

Full-endoscopic lumbar discectomy (FELD) is a minimally invasive surgical option for recurrent lumbar disc herniation (LDH). Nonetheless, patients' clinical outcomes may be poorer after surgery for recurrent LDH than for primary LDH. Therefore, we compared patients' longitudinal clinical outcomes after FELD for recurrent LDH or primary LDH.The medical records of patients who underwent FELD for primary LDH (group A) or recurrent LDH (group B) were retrospectively reviewed. The inclusion criteria were: 1) single-level LDH or recurrent LDH at L4-5 or L5-S1, 2) age ≤60 years, 3) previous open discectomy (group B), and 4) ≥6 months of follow-up. In total, 244 patients (group A, 211; group B, 33) were included. Clinical outcomes (Oswestry Disability Index [ODI]; visual analogue pain score for the back and leg [VAS-B] and [VAS-L]) over 24 months of follow-up were compared between groups with a linear mixed-effects model.All clinical outcomes significantly improved from pre-operation to 3 months postoperatively (p 0.01), and the improvement was maintained for 24 months postoperatively in both groups. The clinical outcomes of groups A and B were not significantly different during 24 months follow-up (ODI, p = 0.94; VAS-B, p = 0.11; and VAS-L, p = 0.48). The reoperation rate was 3.3% in group A and 3.0% in group B, but the overall complication rate was higher in group B (9.8%) than in group A (6.6%).The longitudinal clinical outcomes after FELD for recurrent LDH may not be poor as feared. However, the higher complication rate in patients undergoing FELD for recurrent LDH should be noted.

Background Post-transplantation diabetes mellitus (PTDM) is associated with a higher risk of mortality and graft loss. The reported incidence of PTDM after kidney transplantation (KT) varies from 10% to 74% and varies by country and ethnicity. There are few reports of nationwide cohort studies on PTDM incidence and related factors in Korea. The purpose of this study was to evaluate incidence of PTDM and related factors within 1 year after KT in Korea. Methods The KoreaN cohort study for Outcome in patients With Kidney Transplantation (KNOW-KT) enrolled 1080 recipients from July 2012 to August 2016. This study included 723 recipients, excluding 273 patients with pretransplant DM and 84 patients who were lost from follow-up within 1 year after KT. Results Among 723 recipients, 85 (11.8%) recipients were diagnosed and treated with PTDM. Recipient age, HLA mismatches, hemoglobin A1c (HbA1c), waist-hip ratio (WHR), and use of prednisolone were significantly higher in PTDM group than the nondiabetic group. In the multivariable logistic regression analysis, independent risk factors for PTDM were older recipient age, higher WHR, and HbA1c before KT. Conclusion The incidence of PTDM was 11.8% in a nationwide Korean cohort study. The factors related to the development of PTDM within 1 year after KT were older recipient age and higher WHR, and HbA1c levels before KT. In recipients with high WHR, it is important to control pretransplant abdominal obesity to prevent PTDM after KT.

Objective Theoretically, the optimal approach is determined by the status of ossification of the posterior longitudinal ligament (OPLL) and sagittal alignment. However, there have long been disputes about the optimum surgical approach of OPLL. This study is to compare risk-effectiveness between anterior decompression and fusion (ADF) and laminoplasty and laminectomy with fusion (LP/LF) for the patient with cervical myelopathy due to multilevel cervical OPLL. Methods We searched core databases, and compared complication and outcomes between ADF and LP/LF for patients with multiple OPLL for the cervical spine. The incidence of complications such as neurologic deterioration, C5 palsy, and dura tear was assessed. Changes in JOA score between baseline and final evaluations were assessed for 2 groups. The minimal clinically important difference (MCID) was utilized for evaluating clinical significance. We calculated Peto odds ratio (POR) and mean difference for the incidence and continuous variables, respectively. Results We included data from 21 articles involving 3,872 patients with cervical myelopathy with OPLL. Major neurologic deficits such as paraplegia, quadriplegia developed 2.17% in the ADF group and 1.11% in the LP/LF group, and POR was 2.16. Mean difference of JOA score improvement of 2 groups was 1.30, and the mean difference showed a statistical significance. However, 1.3 points of JOA improvement cannot reach 2.5 points of the MCID. Conclusion Anterior surgery often led to rare but critical complications, and the difference of neurological improvement between 2 groups was below a clinically meaningful level. Posterior surgeries may be appropriate in the treatment of multilevel cervical myelopathy with OPLL.

Tuberculosis (TB), which is caused by Mycobacterium tuberculosis (MTB), is a serious infectious disease with high infection and mortality rates and is a public health problem around the world. According to the World Health Organization (WHO) report, one-third of the world's population is latently infected with MTB, and 5 to 10% of those with latent TB infection (LTBI) have the potential to develop active TB once in their lifetime. Therefore, TB management for promptly distinguishing LTBI from active TB and for proper treatment is important. LTBI is currently diagnosed using the tuberculin skin test (TST) and interferon gamma (IFN-γ) release assay (IGRA). However, this test is substantially limited by its inability to distinguish active TB from LTBI. It is necessary to discover indicators that can be used for effective TB management and to develop diagnostic methods. In the present study, we used IGRA and complete blood count (CBC) analysis for discrimination of active TB, LTBI, and healthy control groups. The results showed that the number of WBC was significantly increased in the group with active TB (p

Radiotherapy has played an important role in the treatment of spinal metastases. One of the major complications of radiotherapy is vertebral compression fracture (VCF). Although the spinal instability neoplastic score (SINS) was developed for evaluating spinal instability in patients with spinal metastases, it is also commonly used to predict VCF after radiotherapy in patients with spinal metastases. However, its accuracy for predicting radiotherapy-induced VCF and precision remain controversial. The aim of this study was to clarify the diagnostic value of the SINS to predict radiotherapy-induced VCF and to make recommendations for improving its diagnostic power. We searched core databases and identified 246 studies. Fourteen studies were analyzed, including 7 studies (with 1269 segments) for accuracy and 7 studies (with 280 patients) for precision. For accuracy, the area under the summary receiver operating characteristic curve was 0.776. When a SINS cut-off value of 7 was used, as was done in the included studies, the pooled sensitivity was 0.790 and the pooled specificity was 0.546. For precision, the summary estimate of interobserver agreement was the highest dividing 2 categories based on a cut-off value of 7, and the value was 0.788. The body collapse showed moderate relationship and precision with the VCF. The lytic tumor of bone lesion showed high accuracy and fair reliability, while location had excellent reliability, but low accuracy. The SINS system can be used to predict the occurrence of VCF after radiotherapy in spinal metastases with moderate accuracy and substantial reliability. Increasing the cut-off value and revising the domains may improve the diagnostic performance to predict the VCF of the SINS.

There have been few reports on the kinetics of hemodialyzed (HD) patients’ immune responses in latent tuberculosis infection (LTBI). Therefore, in the present study, messenger ribonucleic acid (mRNA) expression levels of nine immune markers were analyzed to discriminate between HD patients with LTBI and healthy individuals. Nine cytokines and chemokines were screened through relative mRNA expression levels in whole blood samples after stimulation with Mycobacterium tuberculosis (MTB)-specific antigens from HD patients with LTBI (HD/LTBI), HD patients without LTBI, and healthy individuals, and results were compared with the QuantiFERON-TB Gold In-Tube (QFT-GIT) test. We confirmed that the C-C motif chemokine 11 (CCL11) mRNA expression level of the HD/LTBI group was significantly higher than the other two groups. Especially, the CCL11 mRNA expression level of the &gt, 0.7 IU/mL group in the QFT-GIT test was significantly higher than the &lt, 0.2 IU/mL group in the QFT-GIT test and the 0.2–0.7 IU/mL group in the QFT-GIT test (p = 0.0043). The present study reveals that the relative mRNA expression of CCL11 was statistically different in LTBI based on the current cut-off value (i.e., ≥0.35 IU/mL) and in the &gt, 0.7 IU/mL group. These results suggest that CCL11 mRNA expression might be an alternative biomarker for LTBI diagnosis in HD patients.

Physicians often encounter surgical candidates with lumbar disc herniation (LDH) who request non-surgical management even though surgery is recommended. However, second opinions may differ among doctors. Therefore, a prospective comprehensive cohort study (CCS) was designed to assess outcomes of nonsurgical treatment for surgical candidates who were recommended to undergo surgery for LDH but requested a second opinion. The CCS includes both randomized and observational cohorts, comprising a nonsurgery cohort and surgery cohort, in a parallel fashion. Crossover between the nonsurgery and surgery cohorts was allowed at any time. The present study was an as-treated interim analysis of 128 cases (nonsurgery cohort, n = 71; surgery cohort, n = 57). Patient-reported outcomes included visual analogue scores for the back (VAS-B) and leg (VAS-L), the Oswestry Disability Index, the EuroQol 5-Dimension instrument, and the 36-Item Short-Form Health Survey (SF-36), which were evaluated at baseline and at 1, 3, 6, 12, and 24 months. At baseline, age and SF-36 physical function were significantly lower in the surgery cohort than in the nonsurgery cohort (p 0.01). Nonsurgical management may be a negotiable option even for surgical candidates in the shared decision-making process.

Although extradural nerve plexus tumors in brachial and lumbosacral plexuses are rare, the removal of the tumors should be considered. The surgical strategy requires not only the anatomical understanding but also the appropriate surgical approach according to tumor characteristics. In the present chapter, we describe the general concepts for the tumors and show the way how to surgically approach the tumors.

Background The incidence of Tuberculosis (TB) is higher in patients undergoing chronic hemodialysis than in the general population; further, both the incidence and development of active TB from latent TB infection (LTBI) are considerably higher in patients undergoing hemodialysis than in any other group. The QuantiFERON-TB Gold In-Tube (QFT-GIT) assay is one of the most commonly used interferon gamma (IFN-γ) release assays (IGRAs) currently. We aim to know T-cell function of hemodialysis patients and the possible QFT false negatives. Methods In order to analyze the MTB-specific antigen-stimulated IFN-γ release in patients on hemodialysis, the QFT-GIT test was used in this study. A total of 84 hemodialysis patients and 52 healthy subjects were enrolled from Kosin University Gospel Hospital and Catholic University of Pusan, Busan, Republic of Korea; their whole blood samples were collected and used for the present study. Results The positivity results of the IGRAs in hemodialysis patients and normal subjects were 34/84 (40.4%) and 4/52 (7.6%), respectively. The mean value of MTB-specific antigen-stimulated IFN-γ in hemodialysis patients with LTBI and non-LTBI status in hemodialysis patients, healthy individuals were 1.85 IU/mL (4.44ng/mL) and 0.028 IU/mL (0.067 ng/mL) and 0.255 IU/mL (0.612 ng/mL) respectively. In addition, Of the 34 LTBI status in hemodialysis patients, 14 (41.2%) had T-cell mitogen-stimulated IFN-γ levels of 10 or less, and 20 (58.8%) had 10 or more T-cell mitogen-stimulated IFN-γ. Moreover, Of the 49 non-LTBI status in hemodialysis patients, 19 (38.8%) had T-cell mitogen-stimulated IFN-γ levels of 10 or less, and 30 (61.2%) showed T-cell mitogen-stimulated IFN-γ levels of 10 or more. On the other hand, there was no low level of T-cell mitogen-stimulated IFN-γ in the healthy individuals. Conclusion This reveals that T-cell function in hemodialysis patients was reduced as compared to the healthy individuals. Therefore, the cut-off value should be adjusted for the active TB high-risk group when using IGRA tests. The clinical manifestations of TB in patients on hemodialysis are quite non-specific, making timely diagnosis difficult, and delaying the initiation of curative treatment, delay being a major determinant of outcome.

BackgroundThe objective of this study was to develop a probabilistic graphical model (PGM) to show the personalized prediction of clinical outcome in patients with cervical spondylotic myelopathy (CSM) with different clinical conditions after posterior decompression and to use the PGM to identify causal predictors of the outcome.MethodsWe included data from 59 patients who had undergone cervical posterior decompression for CSM. The candidate predictive parameters were age, sex, body mass index, trauma history, symptom duration, preoperative and last Japanese Orthopaedic Association (JOA) scores, gait impairment, claudication, bladder dysfunction, Nurick grade, American Spinal Injury Association (ASIA) grade, smoking, diabetes mellitus, cardiopulmonary disorders, hypertension, stroke, Parkinson disease, dementia, psychiatric disorders, arthritis, ossification of the posterior longitudinal ligament, cord signal change in T1-weighted images, postoperative kyphosis, and cord compression ratio. Statistical and Bayesian network analyses were used to create the PGM and identify predictive factors.ResultsIn multiple linear regression analysis, preoperative JOA score, presence of a psychiatric disorder, and ASIA grade were identified as significant factors associated with the last JOA score. Dementia, sex, preoperative JOA score, and gait impairment were causal factors in the PGM with 93.2% accuracy. Sex, dementia, and preoperative JOA score were direct causal factors related to the last JOA score. Being female, having dementia, and a low preoperative JOA score were significantly related to having a low last JOA score. The PGM showed that preoperative JOA score and sex did not affect the last JOA score in patients with dementia. The probability of having a high last JOA score was higher in men with a high preoperative JOA score than in women with the same preoperative state (74% vs. 2%, respectively).ConclusionsThe causal predictors of surgical outcome for CSM were sex, dementia, and preoperative JOA score. Use of the PGM with the Bayesian network may be useful personalized medicine tool for predicting the outcome for each patient with CSM.

Objective Ligamentum flavum (LF) is an important anatomical structure for prevention of postoperative adhesions, but the opening of LF is necessary for percutaneous endoscopic lumbar interlaminar discectomy (PEID). Although the defect in LF is small with conventional PEID, the defect could be minimized with LF splitting technique. The objective of this study was to compare clinical outcomes of PEID with opening of LF versus splitting of LF. Methods A retrospective study was performed for patients underwent PEID for L5–S1. PEID with the opening of LF (open-group) was performed for 55 patients and with splitting of LF (split-group) was performed for 34 patients. The defect of LF in Open-group was 3–5 mm, but the defect was negligible in split-group because the split LF was reapproximated by its elasticity. Clinical outcomes were evaluated with Korean version of the Oswestry Disability Index (K-ODI) and visual analogue pain scores for back (VASB) and leg (VASL). The changes of clinical outcomes during postoperative 24 months between groups were evaluated with linear mixed-effects model. Results The clinical outcomes were similar between groups for K-ODI (p=0.98), VASB (p=0.52), and VASL (p=0.59). Each outcome demonstrated significant improvement from preoperative baseline throughout the postoperative 24 months (p

Study design A retrospective cohort study. Objective The objectives of the present study were to examine the changes in the number of surgeries, surgical methods selected, and reoperation rates between the years 2003 and 2008. Summary of background data The selection of the appropriate surgical method between decompression-only (D) and decompression plus fusion (DF) represents a challenging clinical dilemma in patients with degenerative lumbar spinal spondylolisthesis. DF is selected in greater than 90% of patients, mostly due to the associated low reoperation rate. However, the outcomes of D have been improved with minimally invasive decompression surgery techniques. Methods The Health Insurance Review and Assessment Service database was used to create cohorts of all Korean patients who underwent surgery for degenerative lumbar spinal spondylolisthesis in 2003 (2003 cohort, n = 5624) and 2008 (2008 cohort, n = 11,706). All patients were followed up for at least 5 years. Reoperation was defined as the occurrence of any type of second lumbar surgery during the follow-up period. The probabilities of reoperation were calculated using the Kaplan-Meier method. Results The number of surgeries increased 2.08-fold in 2008. Patients older than 60 years comprised 38.6% of the 2003 cohort and 52.4% of the 2008 cohort. The proportion of DF surgery was 31.13% in the 2003 cohort but 91.54% in the 2008 cohort. However, the high proportion of fusion surgery failed to reduce the reoperation probability in the 2008 cohort (8.1%) compared with that in the 2003 cohort (6.2%). The cost of DF was US$5264 and that of D was $2719 in 2008. DF decreased the reoperation probability by 1% at the cost of $421/patient in the 2008 cohort. Conclusion The increased proportion of fusion surgery without improvement in reoperation probability in an aging society may be cautiously addressed in deciding future health policies. Level of evidence 4.

Study design Retrospective cohort study of a nationwide sample database. Objective The objective of the present study was to compare the long-term incidence of reoperation for lumbar spinal stenosis (LSS) after anterior fusion, posterior fusion, and decompression. Summary of background data Surgical treatment for LSS can be largely divided into 2 categories: decompression only and decompression with fusion. A previous nationwide study reported that fusion surgery was performed in 10% of patients with LSS, and the 10-year reoperation rate was approximately 17%. However, with the development of surgical techniques and changes in surgical trends, these results should be reassessed. Methods The National Health Insurance Service-National Sample Cohort of the Republic of Korea was utilized to establish a cohort of adult patients (N = 1400) who first underwent surgery for LSS during 2005 to 2007. Patients were followed for 8 to 10 years. Considering death before reoperation as a competing event, reoperation hazards were compared among surgical techniques using a Fine and Gray regression model after adjustment for sex, age, diabetes, osteoporosis, Charlson comorbidity index, severity of disability, type of medical coverage, and type of hospital. Results The overall cumulative incidence of reoperation was 6.2% at 2 years, 10.8% at 5 years, and 18.4% at 10 years. The cumulative incidence of reoperation was 20.6%, 12.6%, and 18.6% after anterior fusion, posterior fusion, and decompression, respectively, at 10 years postoperatively (P = 0.44). The first surgical technique did not affect the reoperation type (P = 0.27). Decompression was selected as the surgical technique for reoperation in 83.5% of patients after decompression, in 72.7% of patients after anterior fusion, and in 64.3% of patients after posterior fusion. Conclusion The initial surgical technique did not affect reoperation during the 10-year follow-up period. Decompression was the most commonly used technique for reoperation. Level of evidence 4.

Objective To determine the prevalence of osteoporosis (OP) and osteoporotic vertebral fracture (OVF) in people with Parkinson's disease (PD) in Korea and its association with socioeconomic status. Methods Using Health Insurance Review and Assessment Service-National Inpatient Sample (HIRA-NIS) data from 2009 to 2013, we estimated the annual prevalence of PD, OP, and OVF and investigated its association with socioeconomic status using data from National Health Insurance (NHI) beneficiaries and Medical Aid (MA) recipients. This study was supported by research funding from Korean Society for Bone and Mineral Research 2015. There were no study-specific biases related to conflicts of interest. Results The number of PD patients in the HIRA-NIS increased each year from 2009 to 2013. Among patients with PD, the standardized prevalence rates of OP and OVF increased from 2009 to 2013; from 23.2 to 27.8 and from 2.8 to 4.2, respectively. Among patients with PD with OP, the prevalence of OVF were 12.2% and 15.1% in 2009 and 2013, respectively. The standardized prevalence rates of PD with OP and PD with OVF were significantly higher in MA recipients than in NHI beneficiaries. Conclusion The prevalence of PD both with OP and with OVF increased and the prevalence was higher in MA recipients than in NHI beneficiaries. These findings may suggest that age over 65 years, female and low income may be a significant factor related to PD occurring with OP and OVF.

Fabry disease (FD) is an X-linked, recessively inherited, rare, progressive, disorder of glycosphingolipid metabolism affecting multiple organs resulting in organ dysfunction. It is rare to find only one FD affected subject with a de novo mutation. Here we report a case of a 41-year-old Asian male diagnosed with de novo FD. Comprehensive ophthalmological evaluation was performed using slit lamp, color fundus photography, optical coherence tomography, fluorescein angiography, and indocyanine green angiography. On slit lamp examination, cornea verticillata and slightly tortuous, and aneurysmal dilatation of inferior bulbar conjunctival vessels were observed. Other imaging modalities showed unremarkable findings. Cornea verticillata and inferior bulbar conjunctival vascular abnormalities may be detected earlier than other ocular abnormalities in de novo FDs like hereditary FDs.

Cranial nerve palsies are relatively common after trauma, but trochlear nerve palsy is relatively uncommon. Although traumatic trochlear nerve palsy is easy to diagnose clinically because of extraocular movement disturbances, radiologic evaluations of this condition are difficult to perform because of the nerve's small size. Here, we report the case of a patient with delayed traumatic trochlear nerve palsy associated with a traumatic subarachnoid hemorrhage (SAH) and the related radiological findings, as obtained with high-resolution three-dimensional (3D) magnetic resonance imaging (MRI). A 63-year-old woman was brought to the emergency room after a minor head trauma. Neurologic examinations did not reveal any focal neurologic deficits. Brain computed tomography showed a traumatic SAH at the left ambient cistern. The patient complained of vertical diplopia at 3 days post-trauma. Ophthalmologic evaluations revealed trochlear nerve palsy on the left side. High-resolution 3D MRI, performed 20 days post-trauma, revealed continuity of the trochlear nerve and its abutted course by the posterior cerebral artery branch at the brain stem. Chemical irritation due to the SAH and the abutting nerve course were considered causative factors. The trochlear nerve palsy completely resolved during follow-up. This case shows the usefulness of high-resolution 3D MRI for evaluating trochlear nerve palsy.

Background : The long-term prognosis of BK virus-associated nephropathy (BKVAN) in kidney transplant recipients (KTRs) is uncertain. We evaluated the long-term prognosis in KTRs with BKVAN and the clinical significance of BKVAN on post-transplant clinical outcome. Methods : We retrospectively analyzed the medical records of 582 patients who underwent kidney transplant (KT) between 2001 and 2014. We divided the patients into a BKVAN group (15 patients) diagnosed by allograft biopsy and a control group (356 patients). Results : The incidence of BKVAN was 4.0%, and the mean follow-up duration was 93.1 ± 52.3 months. Median time from KT to BKVAN diagnosis was 5.9 months (interquartile range [IQR], 4.4-8.7). In the BKVAN group, 9 (60.0%) KTRs with combined acute rejection progressed to graft failure, and the median time from BKVAN diagnosis to graft failure was 36.2 months (IQR, 9.7-65.5). Death-censored graft survival rate and patient survival rate in the BKVAN group were significantly lower than those in the control group. BKVAN and rejection were independent risk factors for graft failure. In the subgroup analysis, death-censored graft survival rate of KTRs with BKVAN with acute rejection was significantly worst in comparison with similar patients without BKVAN regardless of acute rejection (P ＜ 0.001). Conclusion : The long-term prognosis of BKVAN with acute rejection was very poor because of graft failure caused by inadequate treatment for acute rejection considering BKVAN. Therefore, we should carefully monitor the allograft status of KTRs through regular surveillance tests after treatment for BKVAN with acute rejection.

Background Although the hospitalization rate at early period of kidney transplantation (KT) is still high, the association between the hospitalization within 1 year after KT and graft survival is unclear. We investigated the incidence and causes of hospitalization and clinical outcome of the patients hospitalized within 1 year after KT. Methods We retrospectively analyzed 174 KT recipients (KTRs) hospitalized within 1 year after KT between 2013 and 2015. Results Among them, 84 (48%) KTRs were admitted within 1 year after KT, and the number of hospitalizations was 116. The mean time from KT to first hospitalization was 4.2 months. Seventy-eight percent of the patients were hospitalized for medical causes and 22% for surgical causes. The most common cause was cytomegalovirus infection (CMV) (23.3%), followed by acute rejection (11.2%) and urinary tract infection (10.3%). Recipients and donors in the hospitalized group were significantly older than the nonhospitalized group. The proportions of deceased donor KT, acute rejection, more than 50% panel-reactive antibody, and positive donor-specific antibody were significantly higher in the hospitalized group than in the nonhospitalized group. Graft and patient survivals were lower in the hospitalized group than in the nonhospitalized group. Deceased donor KT and acute rejection were independent risk factors for hospitalization. Conclusion The incidence of KTRs hospitalized within 1 year after KT was high. Most causes of hospitalization were CMV infection, acute rejection, and urinary tract infection. Therefore, the immunosuppression status of these patients should be closely monitored to reduce the hospitalization rate.

Objective To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis. Methods We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest. Results There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively). Conclusion When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.

This study investigated the clinical outcomes and mid- to long-term survival rates in patients undergoing transtibial pullout repair of medial meniscus posterior root tears (MMPRTs) after a minimum follow-up of 5 years.Between 2005 and 2011, patients with MMPRTs who had been followed for at least 5 years after undergoing transtibial pullout repair were recruited. Participants were identified using medical records and information in a prospectively collected database. Clinical outcomes were assessed based on a comparison of patient preoperative Lysholm scores and their scores at the final follow-up. A Kaplan-Meier survival analysis was used to investigate the survival rates of repair procedures. Clinical failures were defined as cases requiring conversion to total knee arthroplasty (TKA) or having final Lysholm score65 or less than their preoperative scores.Overall, 91 patients (mean age, 58.7 ± 9.7 years) were included: the mean follow-up duration was 84.8 ± 13.8 months. Among these patients, the mean Lysholm score improved significantly from 51.8 ± 7.9 preoperatively to 83.0 ± 11.1 at the final follow-up (P.001). Overall, 4 patients failed due to conversion to TKA (n = 1) or having final Lysholm scores65 or less than the preoperative scores (n = 3). The overall Kaplan-Meier probabilities of survival after repair were 99% at 5 years, 98% at 6 years, 95% at 7 years, and 92% at 8 years.Among patients with MMPRTs, transtibial pullout repair demonstrated a high clinical survival rate and the patients demonstrated clinical improvement, based on mid- and long-term follow-up examinations.Level IV, retrospective uncontrolled case series.

Objective The purpose of this study is to describe the detailed surgical technique and short-term clinical and radiological outcomes of lateral lumbar interbody fusion (LLIF) and in situ lateral screw fixation using a conventional minimally invasive screw fixation system (MISF) for revision surgery to treat rostral lumbar adjacent segment disease. Methods The medical and radiological records were retrospectively reviewed. The surgery was indicated in 10 consecutive patients with rostral adjacent segment stenosis and instability. After the insertion of the interbody cage, lateral screws were inserted into the cranial and caudal vertebra using the MISF through the same LLIF trajectory. The radiological and clinical outcomes were assessed preoperatively and at 1, 3, 6, and 12 months postoperatively. Results The median follow-up period was 13 months (range, 3-48 months). Transient sensory changes in the left anterior thigh occurred in 3 patients, and 1 patient experienced subjective weakness; however, these symptoms normalized within 1 week. Back and leg pain were significantly improved (p

Retrospective analysis.The object is to assess the correlation between whole lumbar lordosis (LL) and the segmental angle (SA) after single-level anterior lumbar interbody fusion for degenerative lumbar spondylolisthesis.The restoration of the SA at lower lumbar spine is meaningful, considering it contributes approximately 60% of LL, and revision surgery due to flat back or adjacent segment pathology was necessary decades after the initial surgery. However, little is known about the change of whole lumbar curvature after single-level lower lumbar fusion surgery, especially for balanced spine.We included 41 consecutive patients (M:F=9:32; mean age, 59.8±9.3 y) with a single-level anterior lumbar interbody fusion surgery for low-grade degenerative spinal spondylolisthesis, with C7 plumb line of5 cm and ≥2-year follow-up period. The operated levels were L4-L5 in 34 patients and L5-S1 in 7 patients. Whole LL, SA, pelvic tilt, and sacral slope were compared.According to the Macnab criteria, a favorable outcome (excellent, 21; good, 15) was achieved in 36/41 (88%; excellent, 21; good, 15) patients. LL and SA were significantly changed from -50.8±9.9 to -54.6±11.1 degrees and -15.6±6.1 to -18.7±5.1 degrees (P0.01), and a positive correlation (r=0.43, P=0.01) was observed between LL and SA at postoperative month 24. The changes to the pelvic tilt and sacral slope were not significant.Whole lumbar sagittal alignment was influenced by single SA. Therefore, obtaining adequate segmental lordosis is desirable considering the effect on the whole spine for a long time.

Introduction The recurrence of IgA nephropathy (IgAN) after kidney transplantation (KT) has an effect on graft survival, but there are few reports about long-term clinical outcomes of KT with recurrent IgAN. This study shows the long-term clinical outcomes of KT in patients with IgAN. Methods All recipients who had biopsy-proven IgAN were followed from February 1990 to February 2016. We analyzed overall graft and patient survival rates, incidence of recurrent IgAN, factors affecting graft survival, and IgAN recurrence. Results There were 88 patients with first KT. The mean follow-up duration was 82.5 months. Twenty patients went through graft loss and 1 patient died due to sepsis. IgAN recurred in 15 patients, and 11 patients experienced graft failure. Among the patients who had failed graft after first KT, 7 patients underwent retransplantation. The graft survival period, presence of rejection, and proteinuria were the relevant risk factors for recurrence of IgAN. In the first KT patients, presence of rejection and 1-year serum creatinine were the significant risk factors for graft loss. But recurrence of IgAN was not a relevant risk factor. Overall graft survival rates at 5 and 10 years were 93.8% and 73.1% in the first transplantation group and 100% and 100% in the retransplantation group, respectively. Conclusion Although IgAN recurrence was a significant risk factor for graft failure, the patient who underwent retransplantation showed favorable results. Retransplantation should be considered in patients who lost their first graft after recurrence of IgAN.

Background Diabetes mellitus (DM) is associated with poor postoperative outcomes and increased morbidity after surgeries. Some previous studies have addressed the close association between DM and those leading to reoperations, whereas others have rejected this theory. This study aimed to evaluate the long-term effect of DM on lumbar spinal surgery using data from a nationwide sample cohort. Methods A population-based cohort comprised one million people, which is a 2.1% representative sample of the Korean population. The present study included adult patients with lumbar degenerative diseases (e.g., lumbar spinal stenosis and spondylolisthesis), who underwent their first lumbar surgery in 2006. The cumulative incidence function for reoperation was calculated and multivariate analysis was performed to define correlation between reoperation and independent factors. Results A total of 2020 patients were enrolled and followed up for 10 years. Nondiabetic patients, patients with DM without complication (DwoC), and patients with DM with complication (DwC) accounted for 79.5%, 9.36%, and 11.14% of all patients, respectively. Reoperation incidence stratified by DM was 12.7% for nondiabetic patients, 22.2% for patients with DwoC, and 20.0% for patients with DwC in 10 years of follow-up. During the same period, death, a competing event of reoperation, occurred in 7.8% of nondiabetic patients, in 13.2% of patients with DwoC, and in 20.9% of patients with DwC. Conclusions DM increased 1.65 times the overall cumulative incidences of reoperation after lumbar spinal surgeries for 10 years of follow-up. The reoperation incidence for DwC may be lower than that for DwoC because of a high incidence of death as a competing event of reoperation.

Background: Cytomegalovirus (CMV) infection is a crucial infection in kidney transplant recipients (KTRs) despite advancements in diagnostic and treatment methods. There are still many controversies about the ways to prevent CMV infection. Methods: We retrospectively analyzed 153 KTRs who underwent kidney transplantation (KT) between September 2013 and January 2016. We classified KTRs into two groups: valacyclovir prophylaxis group (intravenous ganciclovir for 2 weeks after KT, followed by oral valacyclovir for 3 months) and historical control group (only intravenous ganciclovir for 2 weeks after KT). We evaluated the incidence of CMV infection, clinical outcomes, CMV-free survival rate between the two groups and risk factors for the development of CMV infection. Results: Mean time between KT and diagnosis of CMV infection was 4.5±3.3 months. The valacyclovir prophylaxis group showed lower incidence of CMV infection than the historical control group (21.7% vs. 43.9%, P=0.011). The valacyclovir prophylaxis group showed higher CMV-free survival rate than the control group (P=0.011). In multivariable-adjusted analysis, independent risk factors for the development of CMV infection were no valacyclovir prophylaxis, older age at KT, thymoglobulin induction, and delayed graft function. Conclusions: Valacyclovir prophylaxis for 3 months showed significant reduction in the incidence of CMV infection in KTRs. Therefore, we suggest valacyclovir prophylaxis for 3 months in KTRs with risk factors such as old age, thymoglobulin induction, and delayed graft function.

We reviewed charts and radiologic studies of 30 patients operated upon by ADR with Mobi-C® in single level since 2006. All patients had healthy cervical facet joints (less than or equal to grade 1 according to grading systems for cervical facet joint degeneration) preoperatively. We assessed clinical outcomes with NDI and VAS on neck and arm over follow-up and also measured ROM at implanted segment on dynamic radiographs during follow-up. The mean follow-up period was 42.4 ± 15.9 months. We then assessed the linearity of changes in ROM at implanted segment through linear mixed model. All patients showed significantly improved clinical outcomes. ROMs at implanted segment were maintained at slightly increased levels until 24 months postoperatively (P = 0.529). However, after 24 months, ROMs at implanted segment decreased significantly until last follow-up (P = 0.001). In addition, the decreasing pattern after 24 months showed a regular regression (P = 0.001). This decline was correlated with decline of extension angle at implanted segment. Based on this regular regression, we estimated that ROMs at implanted segments would be less than 2 degrees at 10.24 years postoperatively. Even though implanted segment maintains its motion for some length of time, we could assume that an artificial disc would have limited life expectancy correlated with the decline of extension angle.

A retrospective cohort study of a nationwide sample database.The objective of the present study was to compare the long-term incidence of reoperation for lumbar herniated intervertebral disc disease (HIVD) after major surgical techniques (open discectomy, OD; laminectomy; percutaneous endoscopic lumbar discectomy, PELD; fusion).HIVD is a major spinal affliction; if the disease is intractable, surgery is recommended. Considering both the aging of patients and the chronicity of lumbar degenerative disease, the effect of surgical treatment for the lumbar spine should be durable for as long as possible.The National Health Insurance Service-National Sample Cohort (NHIS-NSC) of Republic of Korea was utilized to establish a cohort of adult patients (N = 1856) who underwent first surgery for lumbar HIVD during 2005 to 2007. Patients were followed for 8 to 10 years. Considering death before reoperation as a competing event, reoperation hazards were compared among surgical techniques using the Fine and Gray regression model after adjustment for age, gender, Charlson comorbidity score, osteoporosis, diabetes, the severity of disability, insurance type, and hospital type.The overall cumulative incidences of reoperation were 4% at 1 year, 6% at 2 years, 8% at 3 years, 11% at 5 years, and 16% at 10 years. The cumulative incidences of reoperation were 16%, 14%, 16%, and 10% after OD, laminectomy, PELD, and fusion, respectively, at 10 years postoperation, with no difference among the surgical techniques. However, the distribution of reoperation types was significantly different according to the first surgical technique (P 0.01). OD was selected as the reoperation surgical technique in 80% of patients after OD and in 81% of patients after PELD.The probability of reoperation did not differ among OD, laminectomy, PELD, and fusion during the 10-year follow-up period. However, OD was the most commonly used technique in reoperation.4.

Background Context Lumbar spinal stenosis (LSS) is the most common lumbar degenerative disease, and sagittal imbalance is uncommon. Forward-bending posture, which is primarily caused by buckling of the ligamentum flavum, may be improved via simple decompression surgery. Purpose The objectives of this study were to identify the risk factors for sagittal imbalance and to describe the outcomes of simple decompression surgery. Study Design This is a retrospective nested case-control study Patient Sample This was a retrospective study that included 83 consecutive patients (M:F=46:37; mean age, 68.5±7.7 years) who underwent decompression surgery and a minimum of 12 months of follow-up. Outcome Measures The primary end point was normalization of sagittal imbalance after decompression surgery. Methods Sagittal imbalance was defined as a C7 sagittal vertical axis (SVA) ≥40 mm on a 36-inch-long lateral whole spine radiograph. Logistic regression analysis was used to identify the risk factors for sagittal imbalance. Bilateral decompression was performed via a unilateral approach with a tubular retractor. The SVA was measured on serial radiographs performed 1, 3, 6, and 12 months postoperatively. The prognostic factors for sagittal balance recovery were determined based on various clinical and radiological parameters. Results Sagittal imbalance was observed in 54% (45/83) of patients, and its risk factors were old age and a large mismatch between pelvic incidence and lumbar lordosis. The 1-year normalization rate was 73% after decompression surgery, and the median time to normalization was 1 to 3 months. Patients who did not experience SVA normalization exhibited low thoracic kyphosis (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.02–1.10) (p Conclusions Sagittal imbalance was observed in more than 50% of LSS patients, but this imbalance was correctable via simple decompression surgery in 70% of patients.

Highlights • Meckel' diverticulum is the most common congenital anomaly of the small intestine. • It is a relatively not rare disease in the clinical field. • But the presentation as a retroperitoneal abscess as complications of Meckel's diverticulum is a very rare clinical entity. In this report,. • We present a 31-year-old man with perforated Meckel's divertculum with retroperitoneal abscess. • I also reviewed other disease of retroperitoneal abscess. (As I known as, This case report is the first report including review of retroperitoneal abscess)., Introduction The frequent complications of Meckel’s diverticulum are hemorrhage, intestinal obstruction, and inflammation, and perforation. The presentation as a retroperitoneal abscess as complications of Meckel’s diverticulum is a very rare clinical entity. Presentation of case We report a rare case of perforated Meckel's diverticulum with retroperitoneal abscess. A 31-year-old presented with a half-hour history of severe epigastric pain and diffuse periumbilical pain. Abdominal computed tomography (CT) revealed pneumoperitoneum and retroperitoneal abscesses which air, with diffuse infiltration of the small bowel mesentery and a tubular structure that originated in the ileum at the umbilicus level. Preoperative diagnosis was perforation of Meckel's diverticulum or small bowel perforation. We performed an approximate 10-cm segmental resection of the ileum that contained the Meckel’s diverticulum. Discussion Retroperitoneal abscesses are rare complications of Meckel’s diverticulum and are associated with its perforation. Conclusion The complications of Meckel’s diverticulum should be kept in mind in the differential diagnosis of retroperitoneal abscesses.

To explore optic disc and peripapillary retinal nerve fiber layer (RNFL) features associated with glaucomatous optic disc (GOD) in young myopia. Presence of GOD, optic disc tilt, and disc torsion were determined using fundus photographs. If the measured disc tilt ratio was >1.3, the optic disc was classified as tilted. Optic disc torsion was defined as a >15° deviation in the long axis of the optic disc from the vertical meridian. The average and four quadrants RNFL thicknesses were assessed using spectral domain optical coherence tomography (SD-OCT). Logistic regression analyses were performed to identify factors associated with the presence of GOD. Nine hundred and sixty myopic subjects were recruited from four refractive surgery clinic databases. The mean age was 26.6 ± 5.7 years and spherical equivalent (SE) was −5.5 ± 2.5 diopters. Among 960 eyes, 26 (2.7%) received GOD group classification. Among 934 normal eyes, 290 (31.0%) had titled optic discs. Eighteen eyes (69.2%) in the GOD group had tilted optic discs. When compared to normal eyes, the GOD group had significantly higher tilt ratios (1.4 ± 0.2 vs. 1.2 ± 0.1, p

Epithelioid angiomyolipoma (EAML) is an uncommon variant type of angiomyolipoma (AML), occurring primarily in the kidney and characterized by a distinct entity with a possibility of metastatic transformation and distant spread (1, 2). Although the imaging findings of classical AML are well described in the literature, there are only few case reports describing the imaging appearances of EAML especially originating from the retroperitoneum (1-3). Herein, we reported a case of perirenal EAML with computed tomography (CT) and ultrasonography (US) findings. CASE REPORT

Background: Thymoglobulin has been used for induction therapy to prevent acute rejection and delayed graft function (DGF) in kidney transplant patients. However, the usual dose of thymoglobulin is considered to be related with frequent infection. We compared the efficacy and safety of low-dose thymoglobulin to high-dose treatment in high risk recipients with kidney transplantation. Methods: Twenty-one kidney transplant recipients underwent induction treatment with thymoglobulin and were divided into two groups: patients treated with low-dose (＜6.0 mg/kg) and high-dose thymoglobulin (≥6.0 mg/kg). All patients showed one or more risk factors for acute rejection or DGF. The risk factors were re-transplantation, recipient or donor age over 60 years, human leukocyte antigen full mismatch, and panel-reactive antibody more than 50%. We compared incidence of acute rejection, infection, hematologic complications, and graft survival between two groups. Results: The demographic characteristics of the two groups were comparable. Mean follow-up duration was 11.9±4.3 months, and cumulative thymoglobulin dosage was 6.3±1.6 mg/kg. The incidence rates of acute antibody-mediated rejection (AMR), DGF and infectious events as cytomegalovirus disease, or urinary tract infection were not significantly different between the two groups. Neutropenia occurred more frequently in the high-dose thymoglobulin group, but there was no statistically significant difference. The rate of graft loss were similar between the two groups. Conclusions: There were no differences in graft survival, infectious disease, and hematologic problems between the two groups. We suggest to lower the dose of thymoglobulin to less than 6 mg/kg for prevent acute AMR and DGF in high risk patients.