Intervertebral Disc Level Research Articles

O-1-13. Diagnosis of lumbar radiculopathy using magnetospinography

Introduction We previously reported noninvasive visualization of neural activities in the lumbar spine using magnetospinography (MSG). We report here MSG findings of a patient with lumbar radiculopathy. Methods Using a newly developed superconducting quantum interference device (SQUID) magnetometer, we measured the neuromagnetic fields of a patient with L4/-5 disc herniation at the surface of the lumbar spine area after stimulation of the peroneal nerves at the fibular head. Current sources were estimated using spatial filter techniques and were superimposed on X-ray images of the lumbar spine. Results and discussion The action currents calculated from MSG showed a distribution pattern of axonal activity with an intra-axonal current and depolarization/repolarization current. On the contralateral healthy side, the nerve action current passed through the L5 intervertebral foramen and propagated in the caudal-to-cranial direction. On the affected side, the nerve action current attenuated at the L4/-5 intervertebral disc level. Thus, noninvasive surface MSG visualizes propagating spinal nerve excitation in response to peroneal nerve stimulation with high spatial and temporal resolution, allowing us to quantitatively evaluate the decreased action current in lumbar radiculopathy. MSG obtains a different perspective from MRI for the diagnosis of neuropathic pain and is expected to be a clinically useful modality.

The optimal anatomic site for a single slice to estimate the total volume of visceral adipose tissue by using the quantitative computed tomography (QCT) in Chinese population.

To investigate the relationship between the cross-sectional visceral adipose tissue (VAT) areas at different anatomic sites and the total VAT volume in a healthy Chinese population using quantitative computed tomography (QCT), and to identify the optimal anatomic site for a single slice to estimate the total VAT volume. A total of 389 healthy Chinese subjects aged 19-63 years underwent lumbar spine QCT scans. The cross-sectional area of total adipose tissue and VAT were measured using the tissue composition module of the software (QCT Pro, Mindways) at each intervertebral disc level from T12/L1 to L5/S1, as well as at the umbilical level. The total VAT volume was defined as the fat areas multiplied by the height of vertebral body for all six slices. Statistical analysis was performed to determine the correlation between single-slice VAT areas and the total VAT volume. Moreover, the optimal anatomic site for a single slice to estimate the total VAT volume was identified by multiple regression analysis. The cross-sectional area of VAT and subcutaneous adipose tissue (SAT) measured at each anatomic site was all highly correlated with the total VAT volume and the total SAT volume (r = 0.89-0.98). Additionally, the VAT area measured at the L2/L3 level showed the strongest correlation with the total VAT volume (r = 0.98, P < 0.001). Covariates including age, gender, BMI, waist, and hypertension make a slight effect on the prediction of the total VAT volume. It is feasible to perform measurements of VAT area on a single slice at L2/L3 level for estimating the total VAT volume.

High-resolution magnetization transfer MRI in patients with cervical spondylotic myelopathy

Magnetization transfer (MT) contrast has been established as a marker of myelin integrity, and cervical spondylotic myelopathy is known to cause demyelination. Ten patients with clinical and magnetic resonance imaging (MRI) manifestations of cervical spondylotic myelopathy (CSM) were compared to the MRIs of seven historic healthy controls, using the magnetization transfer ratio (MTR) and Nurick scores as the primary metrics. Transverse slices through the intervertebral discs of the cervical spine were acquired using a gradient echo sequence (MEDIC) with and without an MT saturation pulse on a 3 Tesla Siemens Prisma scanner (TR = 300 ms, TEeff = 17 ms, flip angle = 30°, in-plane resolution = 0.47 × 0.47 mm2). The CSM patients tended to have a lower mean MTR (30.4 ± 6.5) than the controls (34.8 ± 3.8), but the difference was not significant (independent samples t-test, p = 0.110, Cohen’s d = 0.80). The mean MTR across all intervertebral disc levels was not significantly correlated to the Nurick score (Spearman’s ρ = −0.489, p = 0.151). The intervertebral level with the lowest MTR in each cohort was not significantly different between groups (equal variances not assumed, t = 1.965, dof = 14.8, p = 0.068, Cohen’s d = 0.88), but the CSM patients tended to have a lower MTR. The mean MTR at this level was negatively correlated to the Nurick score among CSM patients (Spearman’s ρ = −0.725, p = 0.018). CSM patients tended to have decreased MTR indicating myelin degradation compared to our healthy subjects, and MTR was negatively correlated with the severity of CSM.

Sarcopenia in Children With End-Stage Liver Disease.

Sarcopenia, reflected by decreased psoas muscle surface area (PMSA), has been identified as a novel and independent predictor of wait-list mortality and outcomes in adult liver transplantation (LT). We hypothesized that children with end-stage liver disease (ESLD) would have smaller PMSA than healthy controls. Computer tomography images of children (ages 0 to 18 years) listed for LT in 2015 and a control group comprised 2:1 age- and gender-matched healthy pediatric trauma victims were reviewed. PMSA was determined at 2 intervertebral disc (L3/4; L4/5) levels. A subset of images was reviewed by 2 radiologists to determine interrater correlation. A total of 23 children with ESLD were included, and the most prevalent diagnosis was biliary atresia (61%). On both lumbar levels, median PMSA was significantly smaller in ESLD subjects compared with the 46 healthy controls (L4/5; median total PMSA (tPMSA) 407 mm (interquartile range 339-537) versus controls 513 mm (interquartile range 437-672); P = 0.004), independent of participants' weight z scores (r = 0.01; P = 0.95). Excellent interrater correlation was seen (intraclass correlation 0.99). In this retrospective pilot study, PMSA was significantly lower in children with ESLD compared with healthy age- and gender-matched controls. Because this finding was independent of growth in ESLD subjects, PMSA may represent a novel objective nutritional biomarker in children with advanced liver disease.

Early nutritional inadequacy is associated with psoas muscle deterioration and worse clinical outcomes in critically ill surgical patients

PurposeTo explore whether psoas cross sectional area (CSA) and density (Hounsfield Units, HU) are associated with nutritional adequacy and clinical outcomes in surgical intensive care unit patients. Materials and methodsSubjects with at least one CT scan within 72h of ICU admission were included. Demographic, nutritional, radiographic, and outcomes data were collected. Psoas muscle CSA and HU were assessed at the L4–L5 intervertebral disk level. Change (Δ) in CSA and HU overall and per day were calculated. Results140 patients were included. There was no significant correlation between baseline CSA and HU and clinical outcomes. Patients with at least two CT scans (n=65), had a median decrease in CSA of −15% [IQR: −20%, −8%] and decrease in HU of −2% [IQR: −30%, +24%]. Patients with the greatest daily %HU decline received significantly fewer calories/kg and proteins/kg and accumulated greater protein deficits at day 7 and overall. Patients with daily %HU increase had the shortest ICU and hospital LOS and more ventilator-free days in univariate and multivariable analyses. ConclusionsIn this exploratory study, early nutritional deficits were correlated with muscle quality deterioration. Inpatient gain in psoas density, compared to maintenance or loss, is associated with shorter hospital stay.

Morphometric analysis of significant vascular structures in posterior disc surgery with computed tomography angiography.

Vascular injuries, which are rarely seen in all spinal area procedures, especially lumbar disc surgery, are vitally important. The relationship between the course of the iliac artery and vein and intervertebral disc distance was studied morphometrically in patients who had undergone computed tomography angiography for abdominal aorta. This study was carried out retrospectively. A total of 100 patients who had undergone computed tomography angiography participated in the study. The aorta bifurcation, right and left common iliac artery (R/LCIA) and vein (R/LCIV), and the location of the common iliac artery bifurcation were investigated. The location of these vascular structures at the level of the spinal vertebral body and at the intervertebral disc level, determination of a fat plane between them, and the anterior longitudinal ligament (ALL) were analyzed. At the L4-5 intertransversarius dorsalis (IDL), the RCIV was determined to be at the 12 o'clock position RCIA in 51% of cases and between the ratio of 67% ALL. The LCIA was at the 1 o'clock position in 72% and adjacent to the ALL in 47%. The RCIV was located in the 11 o'clock position and there was no fat plane between the RCIV and the ALL in 92%. In 80%, the LCIV was located at the 11-12 o'clock position and in 18% transversely along the 12-1-2 o'clock region. There was no fat plane between the LCIV and the ALL in any patient. At the L5-S1 IDL, the RCIA was observed at the 10 o'clock position in 63%, and there was no fat plane between the RCIA and the ALL. The LCIA was at the 2 o'clock position in 72% and the LCIV was between the ALL and the LCIA in 92%. The RCIV was located at the 9-10 o'clock position in 95% and no fat plane was found between the ALL and the RCIV in 60%. The LCIV was located at the 1-2 o'clock position in 96% and there was no fat plane between the LCIV and the ALL in 92%; it was located close to the ALL. The L4-5 IDL RCIA was located at the midline and at a 30° angle position. The LCIV was located between them. The L5-S1 IDL located at LCIA left at 60° position was quite close to ALL with LCIV. When the distance from the ALL was compared and the frequency of fat planes between the ALL and the CIAs are considered, it can be noted that the RCIA in the L4-L5 IDL (p<0.001) and the LCIA in the L5-S1 IDL (p<0.001) were located remotely and in a more protected position. It should be kept in mind that the LCIV can progress along the L4-5 ID level, adjacent to the ALL, as well as transversely.

Effects of plasma vaporization ablation on expression of inflammatory factors in rabbit model of intervertebral disc degeneration

Intervertebral Disc Degeneration (IDD) is one common disease presented as wrist pain. Plasma vaporization ablation is a novel method treating IDD. This study utilized vaporization ablation on rabbit IDD model, whose expression of inflammatory factors was analysed along with the correlation with plasma vaporization ablation. Rabbit IDD model was generated by puncture approach and treated with plasma vaporization ablation. Control group received no treatment after surgery. MRI scanning was performed on rabbit intervertebral disc. Serum and intervertebral disc tissue samples were collected and tested for expression of Tumor Necrosis Factor α (TNF-α), Interleukin-2 (IL-2) and IL-4 by Enzyme Linked Immunosorbent Assay (ELISA) or Immunohistochemistry (IHC) methods. 2 w after puncture, rabbit had rupture of intervertebral disc fibrous ring, plus change of low-strength T2 signal but not in T1 signal. 4 w after surgery, model rats had further decreased intervertebral disc T2 signals. Both serum and intervertebral disc levels of TNF-α, IL-2 and IL-4 were significantly elevated in model group, and were gradually decreased with elongated treatment (p<0.05). Plasma vaporization ablation can decrease expression of TNF-α, IL-2 and IL-4 in both serum and intervertebral disc tissues, probably forming one mechanism of IDD.

The radiologic anatomy of thyroid cartilage and cricoid cartilage: implications for anterior cervical spine surgery

Objective To measure anatomic data related to the thyroid cartilage and cricoid cartilage and to analyze their implications for anterior spine surgery. Methods From January 2015 to February 2017, Cervical spine CT image data of 309 normal adults (195 males, 114 females) in our department were retrospectively analyzed. The transverse diameters of the thyroid cartilage and the cricoid cartilage was measured at three different levels as follows: the superior border of the thyroid cartilage(SBTC), the inferior border of the thyroid cartilage(IBTC), and the inferior border of the cricoid cartilage(IBCC). At those levels, the corresponding level and transverse diameter of the cervical vertebra or intervertebral disc were also determined. Differences of anatomic parameters for each gender and level, and the relationship between the transverse diameter and height and weight were analyzed. Results The transverse diameters of the thyroid cartilage or cricoid cartilage and the corresponding cervical vertebra or intervertebral disc were associated significantly with height and weight. The transverse diameters of the thyroid cartilage or cricoid cartilage gradually decreased from the level of SBTC (44.30±4.97 mm) to the level of IBTC (41.39±4.62 mm), and the latter to the level of IBCC (26.36±3.79 mm), but increased from the level of SBTC (27.47±2.66 mm) to the level of IBTC(29.00±3.15 mm), and the latter to the level of IBCC (31.48±3.49 mm) for the cervical vertebra or intervertebral disc. Differences of the transverse diameters of the thyroid cartilage or cricoid cartilage and the cervical vertebra or intervertebral disc on three levels had statistical significance. The transverse diameters of each level had individual differences, while men were greater than those for women. The thyroid cartilage was routinely located above the C5 (56.9% for male, 86.0% for female). Differences of the frequency between men and women on three levels had statistical significance. Conclusion The Individual and sex differences in the location of the thyroid cartilage and the size of the thyroid cartilage and the cricoid cartilage provided anatomical basis for predicting the difficulty of intraoperative exposure, incidence of esophageal injuries and early postoperative dysphagia. Key words: Thyroid cartilage; Cricoid cartilage; Anatomy, regional; Spinal fusion; Deglutition disorders

Severe focal myelopathy secondary to chronic compression by an arachnoid pseudocyst in a Rottweiler

A four-year old Rottweiler was presented with tetraplegia, established progressively over a 4-month period. Initiallythe dog developed paresis of the posterior limbs that subsequently evolved to tetraparesis and finally tetraplegia. Upon neurological examination the dog exhibited spastic tetraplegia with exaggerated spinal reflexes in all four limbs. The neuroanatomical lesion localization indicated a focal or diffuse cervical spinal cord disease. Cisternal myelography revealed obstruction of the contrast medium flow at the level of C5 vertebral body. Magnetic resonance imaging disclosed intradural-extramedullary compression of the spinal cord at the level of C5-C6 intervertebral disc by a spinal arachnoid pseudocyst, syrinx formation and myelopathy expressed as abnormally higher signal on T2-weighted images at the C5 segment level. Severe demyelination, involving exclusively the white matter of the grossly affected segments and extending rostrally into the brainstem and caudally into the thoracic spinal cord segments, was noticed on histopathology. The unusually severe secondary degenerative change in the cervical spinal cord white matter, inflicted by focal SAP compression, was the most interesting finding.

Transplantation of dedifferentiation fat cells promotes intervertebral disc regeneration in a rat intervertebral disc degeneration model

Our group has reported that mature adipocyte-derived dedifferentiated fat (DFAT) cells show multilineage differentiation potential similar to that observed in mesenchymal stem cells. In the present study, we examined whether DFAT cell transplantation could contribute to intervertebral disc regeneration using a rat intervertebral disc degeneration (IDD) model. The IDD was created in Sprague-Dawley rats by puncturing at level of caudal intervertebral disc under fluoroscopy. One week after injury, rat DFAT cells (5 × 104, DFAT group, n = 13) or phosphate-buffered saline (PBS, control group, n = 13) were injected into the intervertebral disc. Percent disc height index (%DHI) was measured every week and histology of injured disc was evaluated at 8 weeks after transplantation. Radiographic analysis revealed that the %DHI in the DFAT group significantly higher than that in the control group at 2–3 weeks after transplantation. Histological analysis revealed that ectopic formation of nucleus pulposus (NP)-like tissue at the outer layer of annulus fibrosus was frequently observed in the DFAT group but not in the control group. Transplantation experiments using green fluorescent protein (GFP)-labeled DFAT cells revealed that the ectopic NP-like tissue was positive for GFP, suggesting direct differentiation of DFAT cells into NP-like cells. In conclusion, DFAT cell transplantation promoted the regeneration of intervertebral disc and improved intervertebral disc height in the rat IDD model. Because adipose tissue is abundant and easily accessible, DFAT cell transplantation may be an attractive therapeutic strategy against IDD.

Age-related spontaneous lumbar intervertebral disc degeneration in a mouse model.

The pathogenesis of intervertebral disc degeneration is unclear, but it is a major cause of several spinal diseases. Animal models have historically provided an appropriate benchmark for understanding the human spine. However, there is little information about when intervertebral disc degeneration begins in the mouse or regarding the relationship between magnetic resonance imaging and histological findings. The aim for this study was to obtain information about age-related spontaneous intervertebral disc degeneration in the mouse lumbar spine using magnetic resonance imaging and a histological score regarding when the intervertebral disc degeneration started and how rapidly it progressed, as well as how our histological score detected the degeneration. The magnetic resonance imaging index yielded a moderate correlation with our Age-related model score. The Pfirrmann grade and magnetic resonance imaging index had moderate correlations with age. However, our Age-related model score had a high correlation with age. Intervertebral disc level was not a significant variable for the severity of disc degeneration. Both Pfirrmann grade and the Age-related model score were higher in the ≥14-month-old group than in the 6-month-old group. The present results indicated that mild but significant intervertebral disc degeneration occurred in 14-month-old mice, and the degree of degeneration progressed slowly, reaching a moderate to severe condition for 22-month-old mice. At least a 14-month follow-up is mandatory for evaluating spontaneous age-related mouse intervertebral disc degeneration. The histological classification score can precisely detect the gradual progression of age-related spontaneous intervertebral disc degeneration in the mouse lumbar spine, and is appropriate for evaluating it. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:224-232, 2018.

Variations of renal arteries on 64 slice Multidetector Computed Tomography

IntroductionThe incidence of accessory renal arteries is very high. Multidetector Computed Tomography (MDCT) is a minimally invasive alternative to conventional angiography in preoperative evaluation. The aim of this study was to document the incidence of accessory renal arteries and the level of origin of main renal arteries from abdominal aorta. MethodsThe study was conducted on one hundred patients in whom aortofemoropopliteal or aortic CT angiography was done for various indications at a tertiary care center in North India. CT angiography was performed on 64 slice MDCT scanner. The reconstructed images were analyzed using vessel analysis software. ResultsAccessory renal arteries were present in 36% cases with unilateral anomaly in 30% cases and bilateral in 6% cases. The dominant side of renal artery variations was the right side. All the accessory arteries took origin from the aorta and 52.8% of these supplied the inferior pole of the kidney. In 99% cases the origin of main renal artery was between upper border of L1 vertebra and lower border of L2 vertebra. The most common site of origin was at the level of intervertebral disc between L1 and L2. DiscussionThe incidence of multiple renal arteries is much higher than predicted by various studies. Comprehensive anatomic depiction of the renal arterial pattern aids in determining the technical feasibility of surgical and endourological interventions. It helps to avoid postoperative complications.

Magnetic Resonance Imaging Evaluation of the Effects of Surgical Invasiveness on Paravertebral Muscles After Muscle-preserving Interlaminar Decompression (MILD).

This is a retrospective study. The aim of this study was to determine the extent of damage to the paravertebral muscles after muscle-preserving interlaminar decompression (MILD) using magnetic resonance imaging to evaluate changes in the multifidus muscle (MF). Short-term surgical outcomes of MILD for lumbar spinal canal stenosis (LSCS) are satisfactory; however, the extent of damage to the paravertebral muscles after MILD remains unclear. Thirty-four patients (18 men/16 women; mean age: 72.6 y) who had LSCS treated with MILD were retrospectively investigated. A total of 61 decompressed disk levels [L2/3(5); L3/4(21); L4/5(30); L5/S(5)] and 34 nondecompressed levels (L1/2) were assessed. There was 1 decompressed disk level in 12 cases, 2 in 17 cases, and 3 in 5 cases. Magnetic resonance imaging scans were obtained before surgery and at 3 and 12-18 months after surgery, using the same scanner. The rate of paravertebral muscle atrophy was evaluated to compare the area of the MF in the T2-weighted axial plane (intervertebral disk level) preoperatively and postoperatively, using OsiriX Medical Imaging Software. Changes in muscle signal intensity were also recorded. Statistical analysis was performed using 3-way analysis of variance with the post hoc Fisher PSLD test. The rate of MF atrophy was 4.0% at the decompressed levels and 2.1% at the nondecompressed levels. There were no changes of signal intensity in the MF between the preoperative and postoperative periods. In decompressed levels, muscle atrophy and signal intensity were significantly improved from 3 months to 12-18 months after surgery. The number and level of the decompressed disks did not affect the extent of muscle injury. The extent of paravertebral muscle injury after MILD is satisfactory. The midline interlaminar approach used in this technique may prevent local denervation and irreversible damage to the paravertebral muscles. These results indicate that MILD is useful to treat LSCS less invasively.

Prevalence and Imaging Characteristics of Nonmyelopathic and Myelopathic Spondylotic Cervical Cord Compression.

Cross-sectional population-based observational study. To estimate the prevalence of nonmyelopathic spondylotic cervical cord compression (NMSCCC) and cervical spondylotic myelopathy (CSM) in a population older than 40 years and to evaluate the magnetic resonance imaging (MRI) characteristics of these conditions. The prevalence of neither NMSCCC nor CSM is known and there exists no commonly accepted quantitative MRI definition of cervical cord compression. A group of 183 randomly recruited volunteers, 93 women, median age 66 years, range 40-80 years, underwent MRI examination of the cervical spine and spinal cord on a 1.5 T device using conventional sequences from disc levels C2/C3 to C6/C7. The imaging criterion for cervical cord compression was defined as a change in spinal cord contour at the level of an intervertebral disc on axial or sagittal MRI scan. MRI signs of cervical cord compression were found in 108 individuals (59.0%; 95% CI: 51.5%-66.2%); their numbers increased with age from 31.6% in the fifth decade to 66.8% in the eighth. Clinical signs of symptomatic CSM were found in two cases (1.1%), and 75 cases (41.0%) were without compression. An anteroposterior cervical canal diameter at the level of intervertebral disc (CDdisc) of less than 9.9 mm was associated with the highest probability of NMSCCC-odds ratio (OR) = 32.5, followed by a compression ratio of ≤0.5: OR = 11.1. The prevalence of NMSCCC in a population older than 40 years is higher than previously reported and increases with age. CDdisc and compression ratio had the highest capacity to discriminate between subjects with and without asymptomatic compression, and their cut-off values could be used to objectify criteria for cervical cord compression. 2.

Renal artery entrapment - anatomical risk factors rating.

Cases of renal artery entrapment (RAE) by extrinsic compression have been infrequently reported in the literature. We aimed to describe RAE and elucidate anatomical factors that may be related to renal artery stenosis. Two hundred and four patients' computed tomography scans made for various reasons in Radiology Department from 2011 to 2015 were retrospectively analysed and 7 cases of RAE were found. Authors studied the level of origin of renal arteries vs. coeliac trunk (CT), superior mesenteric artery (SMA) and vertebrae. Diameter of renal arteries, distance between main left renal artery (LRA) and right renal artery (RRA) as well as renal arterial patterns were also investigated. The origin of main renal arteries off the aorta was between the upper margin of L1 and lower margin of L2 vertebra, with the predominant lower 1/3 of L1 vertebra and L1 intervertebral disc. However, in patients with highest range of stenosis of renal artery the origin was most commonly located at the level of Th12 intervertebral disc and upper part of L1. Statistically significant relationships were proven between range of stenosis and level of origin of stenotic renal artery vs. vertebrae (Pearson's correlation coefficient: -0.393, p < 0.01), distance between main LRA and RRA (Pearson's correlation coefficient: 0.398, p < 0.0001), renal artery-CT distance (Pearson's correlation coefficient: -0.263, p < 0.0001), renal artery-SMA distance (Pearson's correlation coefficient: -0.149, p < 0.033). Analysis of RAE allowed finding anatomical factors of renal artery stenosis and classifying them regarding to their importance. Relationship of renal artery origin vs. vertebrae and distance between main LRA and RRA were proven the most important. However, distances between higher originated renal artery and CT, higher originated renal artery and SMA should also be taken into consideration.

Distance between Great Vessels and the Lumbar Spine: MRI Study for Anterior Longitudinal Ligament Release Through a Lateral Approach.

Objective Anterior column reconstruction using the lateral transpsoas approach requires sectioning of the anterior longitudinal ligament while protecting the great vessels. Our aim was to study the anatomical plane of separation between the retroperitoneal vessels and the anterior aspect of the lumbar spine as they relate to safety in the lateral transpsoas anterior column reconstruction procedure. Method A total of 100 T2-weighted magnetic resonance imaging (MRI) examinations were studied. Measurements were obtained for each vertebral body and for each intervertebral disk levels from L1-L2 to L4-L5, and for these vessels: abdominal aorta, inferior vena cava , and common iliac vessels. The following parameters were obtained: (sagittal) total lumbar lordosis and segmental lordosis; (axial) closest distance (areolar space [AS]) between the lumbar spine and vessels; and position of the great vessels. Results The AS was differently distributed for the abdominal aorta and the inferior vena cava. Average values for the inferior vena cava were larger at upper levels (p < 0.001; range: 0.2-9.2 mm), and there were differences between the arteries among the levels (p < 0.001; range: 1.0-4.3 mm) but with no clear difference between the upper and lower lumbar spine. A narrower AS was found at the intervertebral disk level compared with the adjacent vertebral body. At L4-L5, the veins usually lay over the anterior border of the lumbar spine, with substantially wider AS at other lumbar levels. Conclusion The plane between the great vessels and the lumbar spine is differently distributed along the lumbar spine and is especially narrow at lower lumbar levels and in front of the intervertebral disk. The results shown here may help guide surgical decision making for the lateral anterior column reconstruction and may aggregate data from dislocation of the vessels in the lateral decubitus and individualized analysis.

Biochemical validity of imaging techniques (X-ray, MRI, and dGEMRIC) in degenerative disc disease of the human cervical spine—an in vivo study

Background ContextOn a molecular level, maturation or degeneration of human intervertebral disc is among others expressed by the content of glycosaminoglycans (GAGs). According to the degenerative status, the disc content can differ in nucleus pulposus (NP) and annulus fibrosus (AF), respectively. Research in this area was conducted mostly on postmortem samples. Although several radiological classification systems exist, none includes biochemical features. Therefore, we focused our in vivo study on a widely spread and less expensive imaging technique for the cervical spine and the correlation of radiological patterns to biochemical equivalents in the intervertebral discs. PurposeThe aim of this pilot study was to (1) measure the GAG content in human cervical discs, (2) to investigate whether a topographic biochemical GAG pattern can be found, and (3) whether there is a correlation between imaging data (X-ray and magnetic resonance imaging [MRI] including delayed gadolinium-enhanced MRI of cartilage [dGEMRIC] as a special imaging technique of cartilage) and the biochemical data. Study Design/SampleWe conducted a prospective experimental pilot study. Patient SampleOnly non-responders to conservative therapy were included. All subjects were physically and neurologically examined, and they completed their questionnaires. Outcome MeasuresVisual analogue scale neck and arm, Neck Disability Index score, radiological parameters (X-rays, MRI, dGEMRIC), and the content of GAG in the cervical disc were assessed. MethodsAfter surgical removal of 12 discs, 96 fractions of AF and NP were biochemically analyzed for the GAG content using dimethylmethylene blue assay. ResultsA quantitative pattern of GAGs in the human cervical disc was identified. There were (1) significantly (p<.001) higher values of GAGs (µg GAG/mg tissue) in the NP (169.9 SD 37.3) compared with the AF (132.4 SD 42.2), and (2) significantly (p<.005) higher values of GAGs in the posterior (right/left: 149.9/160.2) compared with the anterior (right/left: 112.0/120.2) part of the AF. Third, we found in dGEMRIC imaging a significantly (p<.008) different distribution of GAGs in the cervical disc (NP 1083.3 ms [SD 248.6], AF 925.9 ms [SD 137.6]). Finally, we found that grading of disc degeneration in X-ray and MRI was significantly correlated with neither AF- nor NP-GAG content. ConclusionsThe GAG content in human cervical discs can be detected in vivo and is subject to a significantly (p<.05) region-specific pattern (AF vs. NP; anterior vs. posterior in the AF). Up to the levels of AF and NP, this is reproducible in MRI in dGEMRIC technique, but not in X-ray or standard MRI sequences. Potentially, the MRI in dGEMRIC technique can be used as a non-invasive in vivo indicator for disc degeneration in the cervical spine.

Anatomical Study of Renal Arteries

Arterial supply of the kidney is by the Renal artery. These renal arteries are the Antero lateral branches of the abdominal Aorta at the L1 to L2 Inter vertebral disc level. During the dissection of Cadavers in the department of anatomy we observed more than one arterial supply to the kidney and a number of renal arteries showing early ramification before entering into the hilum of kidney. As per our study 70% of the kidneys are irrigated by single renal artery and 20 % irrigated by the extra renal arteries and 10% specimens showing early ramification. Variations in renal arterial pattern is more common. So it is useful to have awareness to prevent the surgical hazards because of anatomical consideration.

Lumbar intervertebral disc degeneration and related factors in Korean firefighters

ObjectivesThe job of firefighting can cause lumbar burden and low back pain. This study aimed to identify the association between age and lumbar intervertebral disc degeneration and whether the association...

Characteristics of ossification of the spinal ligament; incidence of ossification of the ligamentum flavum in patients with cervical ossification of the posterior longitudinal ligament - Analysis of the whole spine using multidetector CT.

Ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) are characterized by replacement of ligamentous tissue by ectopic new bone formation. Although the background of both diseases might be similar, there are some differences between two diseases. Some patients have both OPLL and OLF. However, the incidence of both OPLL and OLF is still unclear and the precise lesions have not been investigated, yet. This study was conducted to evaluate OLF of the whole spine in patients with cervical OPLL and to analyze the relationship of the ossified lesions between OLF and OPLL. One hundred seventy eight patients who were diagnosed as cervical OPLL by plain radiographs were included. CT images of the whole spine were taken. Ossified lesions were checked at each level of vertebral body and intervertebral disc. The ossification index of OPLL (OPLL OS index) was determined by the sum of the levels of vertebral bodies and intervertebral discs where OPLL existed. The same index was applied for detecting the level of OLF (OLF OS index). Age, gender and OPLL characteristics were compared between the OLF(+) group, OLF was seen at any levels of the spinal canal, and the OLF(-) group, OLF was not seen. The most frequent level of OPLL was at C5 vertebral level and OLF was predominant at upper and lower thoracic levels. Seventeen patients (9.6%) had OPLL and OLF at the same spinal level. The averaged OPLL OS index of the total spine in these patients was 8.7±6.1, ranged from 1 to 36. The averaged OLF OS index of the total spine was 3.1±2.2 (ranged from 1 to 13) in the patients who had OLF at any levels of the whole spine. One hundred fifteen patients (64.6%) with cervical OPLL had OLF at any levels of the whole spine. No relationship was found between the OPLL OS index and the OLF OS index. There was no significant difference among the data between the OLF(+) group and the OLF(-) group. This study demonstrated 64.6% of the patients with cervical OPLL had OLF, mainly in the thoracic spine. However, there was no relationship regarding the severity of the ossified lesions between OPLL and OLF. CT analysis of the whole spine should be carried out for the early detection of OPLL and OLF in patients with cervical OPLL.