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BackgroundOne of the characteristics of spinal stenosis is elastin degradation and fibrosis of the extracellular matrix of the ligamentum flavum. However, there have been no investigations to determine which biochemical factors cause these histologic changes. So we performed the current study to investigate the hypothesis that matrix metalloproteinases (MMPs), which possess the ability to cause extracellular matrix remodeling, may play a role as a mediator for this malady in the ligamentum flavum.MethodsThe ligamentum flavum specimens were surgically obtained from thirty patients with spinal stenosis, as well as from 30 control patients with a disc herniation. The extents of ligamentum flavum elastin degradation and fibrosis were graded (grade 0-4) with performing hematoxylin-eosin staining and Masson's trichrome staining, respectively. The localization of MMP-2 (gelatinase), MMP-3 (stromelysin) and MMP-13 (collagenase) within the ligamentum flavum tissue was determined by immunohistochemistry. The expressions of the active forms of MMP-2, MMP-3 and MMP-13 were determined by western blot analysis, and the blots were quantified using an imaging densitometer. The histologic and biochemical results were compared between the two conditions.ResultsElastin degradation and fibrosis of the ligamentum flavum were significantly more severe in the spinal stenosis samples than that in the disc herniation samples (3.14 ± 0.50 vs. 0.55 ± 0.60, p < 0.001; 3.10 ± 0.57 vs. 0.76 ± 0.52, p < 0.001, respectively). The expressions of the active form of MMPs were identified in all the ligamentum flavums of the spinal stenosis and disc herniation patients. The expressions of active MMP-2 and MMP-13 were significantly higher in the spinal stenosis samples than that in the disc herniation samples (both p < 0.05). The expression of active MMP-3 was slightly higher in the spinal stenosis samples than that in the disc herniation samples, but the difference was not statistically significant (p = 0.131). MMP-2, -3, and -13 were positively stained on the ligamentum flavum fibroblasts.ConclusionsThe current results suggest that the increased expression of active MMPs by the ligamentum flavum fibroblasts might be related to the elastin degradation and fibrosis of the ligamentum flavum in the patients who suffer with lumbar spinal stenosis.

Study DesignIn vitro cell culture.PurposeThe purpose of this study was to investigate the effect of high glucose on autophagy in adult rat intervertebral disc cells.Overview of LiteratureDiabetes mellitus is considered to be an important etiologic factor for intervertebral disc degeneration, resulting in degenerative disc diseases. A glucose-mediated increase of autophagy is a major causative factor for the development of diseases associated with diabetes mellitus. However, no information is available for the effect of high glucose on autophagy in adult intervertebral disc cells.MethodsNucleus pulposus and annulus fibrosus cells were isolated from 24-week-old adult rats, cultured and placed in either 10% fetal bovine serum (normal control) or 10% fetal bovine serum plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days, respectively. The expressions of autophagy markers, such as beclin-1, light chain 3-I (LC3-I) and LC3-II, autophagy-related gene (Atg) 3, 5, 7 and 12, were identified and quantified.ResultsTwo high glucoses significantly increased the expressions of beclin-1, LC3-II, Atg3, 5, 7, and 12 in adult rat nucleus pulposus and annulus fibrosus cells in a dose- and time-dependent manner. The ratio of LC3-II/LC3-I expression was also increased in a dose-respectively time-dependent manner.ConclusionsThe results suggest that autophagy of adult nucleus pulposus and annulus fibrosus cells might be a potential mechanism for the intervertebral disc degeneration in adult patients with diabetes mellitus. Thus, the prevention of autophagy in adult intervertebral disc cells might be considered as a novel therapeutic target to prevent or to delay the intervertebral disc degeneration in adult patients with diabetes mellitus.

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BackgroundPostoperative urinary retention (POUR) may cause bladder dysfunction, urinary tract infection, and catheter-related complications. It is important to be aware and to be able to identify patients at risk of developing POUR. However, there has been no study that has investigated the incidence and risk factors for the development of POUR following anterior cervical spine surgery for degenerative cervical disc disease.MethodsWe included 325 patients (164 male and 161 female), who underwent anterior cervical spine surgery for cervical radiculopathy or myelopathy due to primary cervical disc herniation and/or spondylosis, in the study. We did not perform en bloc catheterization in our patients before the operation.ResultsThere were 36 patients (27 male and 9 female) that developed POUR with an overall incidence of 11.1%. The mean numbers of postoperative in-and-out catheterizations was 1.6 times and mean urine output was 717.7 mL. Thirteen out of 36 POUR patients (36%) underwent indwelling catheterization for a mean 4.3 days after catheterization for in-and-out surgery, because of persisting POUR. Seven out of 36 POUR patients (19%) were treated for voiding difficulty, urinary tract irritation, or infection. Chi-square test showed that patients who were male, had diabetes mellitus, benign prostate hypertrophy or myelopathy, or used Demerol were at higher risk of developing POUR. The mean age of POUR patients was higher than non-POUR patients (68.5 years vs. 50.8 years, p < 0.01).ConclusionsTo avoid POUR and related complications as a result of anterior cervical spine surgery for degenerative cervical disc disease, we recommend that a catheter be placed selectively before the operation in at-risk patients, the elderly in particular, male gender, diabetes mellitus, benign prostate hypertrophy, and myelopathy. We recommend that Demerol not be used for postoperative pain control.

BackgroundThe lateral radiograph-based system described by Tsuyama is used widely to classify ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. However, OPLL is a complex 3-dimensional (3-D) lesion, not a simple and uniplanar one, which is often difficult to identify on a lateral radiograph. Furthermore, its reliability among spine surgeons has not been investigated. Given the popularity of a reconstructed computed tomography (CT), this study examined the inter- and intra-observer reliability of lateral radiograph-based OPLL classification using that modality.MethodsFive spine surgeons independently reviewed the lateral radiograph, axial CT, 2-D (sagittal) and 3-D reconstructed CT images of 108 OPLL patients on 2 separate occasions. Based on these images, the reviewers classified each OPLL case according to the Tsuyama's system. The kappa values were used to assess the statistical reliability.ResultsThe inter- and intra-observer kappa values were only 0.51 and 0.67 for the lateral radiograph, even in combination with the axial CT images, 0.70 and 0.85 for 2-D CT images, and 0.76 and 0.86 for 3-D CT images, respectively. These kappa values showed a good-to-excellent range for the 2-D and 3-D reconstructed CT images while those of the lateral radiograph indicated a fair range. According to the OPLL types, the inter- and intra-observer reliability was low in the continuous type and high in the circumscribed type on the lateral radiograph. However, the low reliability of the continuous type on lateral radiograph was overcome somewhat using 2-D and 3-D reconstructed CT images.ConclusionsThe inter- and intra-observer kappa values were only 0.51 and 0.67 for the lateral radiograph, even in combination with the axial CT images, 0.70 and 0.85 for 2-D CT images, and 0.76 and 0.86 for 3-D CT images, respectively. These kappa values showed a good-to-excellent range for the 2-D and 3-D reconstructed CT images while those of the lateral radiograph indicated a fair range. According to the OPLL types, the inter- and intra-observer reliability was low in the continuous type and high in the circumscribed type on the lateral radiograph. However, the low reliability of the continuous type on lateral radiograph was overcome somewhat using 2-D and 3-D reconstructed CT images.

Permanent post-traumatic patellar dislocation is a rare condition, and total knee arthroplasty (TKA) can be performed for osteoarthritic knees with this condition. There have been only a few reports about using the standard medial parapatellar approach and extensive lateral release or extensor mechanism realignment for patients with permanent post-traumatic patellar dislocation. We performed two TKAs with using a subvastus approach and lateral release for osteoarthritic knees with permanent post-traumatic patellar dislocation. The patients were well satisfied with their results. The patellae tracked very well in the femoral trochlear groove throughout the full range of motion after the operations. Bone scans were done 1 year postoperatively on both patients, and the scans showed normal vascularity for the patella.

Recently, the Device for Intervertebral Assisted Motion (DIAM TM ) has been introduced for surgery of degenerative lumbar disc diseases. The authors performed the current study to determine the survivorship of DIAM TM implantation for degenerative lumbar disc diseases and risk factors for reoperation. One hundred and fifty consecutive patients underwent laminectomy or discectomy with DIAM TM implantation for primary lumbar spinal stenosis or disc herniation. The characteristics of the 150 patients included the following: 84 males and 66 females; mean age at the time of surgery, 46.5 years; median value of followup, 23 months (range 1-48 months); 96 spinal stenosis and 54 disc herniations; and 146 one-level (115, L4-5; 31, L5-6) and 4 two-level (L4-5 and L5-6). In the current study, due to lumbosacral transitional vertebra (LSTV) L6 meant lumbarization of S1 and this had a prominent spinous process so that the DIAM TM was implanted at L5-6. Reoperations due to any reasons of the DIAM TM implantation level or adjacent levels were defined as a failure and used as the end point for determining survivorship. The cumulative reoperation rate and survival time were determined via Kaplan-Meier analysis. The log-rank test and Cox regression model were used to evaluate the effect of age, gender, diagnosis, location, and level of DIAM TM implantation on the reoperation rate. During a 4-year follow-up, seven patients (two males and five female) underwent reoperation at the DIAM TM implantation level, giving a reoperation rate of 4.7%. However, no patients underwent reoperation for adjacent level complications. The causes of reoperation were recurrent spinal stenosis (n = 3), recurrent disc herniation (n = 2), post-laminectomy spondylolisthesis (n = 1), and delayed deep wound infection (n = 1). The mean time between primary operation and reoperation was 13.4 months (range 2-29 months). Kaplan-Meier analysis predicted an 8% cumulative reoperation rate 4 years post-operatively. Survival time was predicted to be 45.6 ± 0.9 months (mean ± standard deviation). Based on the log-rank test, the reoperation rate was higher at L5-6 (p = 0.002) and two-level (p = 0.01) DIAM TM implantation compared with L4-5 and one-level DIAM TM implantation. However, gender (p = 0.16), age (p = 0.41), and diagnosis (p = 0.67) did not significantly affect the reoperation rate of DIAM TM implantation. Based on a Cox regression model, L5-6 [hazard ratio (HR), 10.3; 95% CI, 1.7-63.0; p = 0.01] and two-level (HR, 10.4; 95% CI, 1.2-90.2; p = 0.04) DIAM TM implantation were also significant variables associated with a higher reoperation rate. Survival time was significantly lower in L5-6 (47 vs. 22 months, p = 0.002) and two-level DIAM TM implantation (46 vs. 18 months, p = 0.01) compared with L4-5 and one-level DIAM TM implantation. The current results suggest that 8% of the patients who have a DIAM TM implantation for primary lumbar spinal stenosis or disc herniation are expected to undergo reoperation at the same level within 4 years after surger...