Fourth Lumbar Research Articles

Lumbar vertebral bone density is decreased in horses with pituitary pars intermedia dysfunction.

Pathological fractures have been reported in equids with pituitary pars intermedia dysfunction (PPID) but their prevalence and pathogenesis is unknown. To compare: (1) bone mineral density (BMD) in weight bearing and nonweight bearing bones in PPID+ equids and aged and young PPID- controls; and (2) biomechanical properties of the fourth lumbar vertebral body in PPID+ equids and aged PPID- equids. Case-control study: five PPID+ equids and six aged and four young PPID- control horses. PPID status was based on clinical signs and necropsy examination of the pituitary gland (PG). The lumbar vertebral column, right front third metacarpus (MC3), left hind third metatarsus (MT3), and PG were removed after euthanasia. BMD was determined by quantitative computed tomography of regions of interest (ROI) in each bone and biomechanical testing was performed on the fourth lumbar vertebral body. Serum concentrations of parathormone (PTH), ionised Ca++ , 25-hydroxyvitamin D, and osteocalcin (OC) were also measured. Data were analysed using one-way ANOVA and correlation analyses. BMD of trabecular and cortical regions of interest (ROI) of the third, fourth (L4), and fifth lumbar vertebrae were significantly lower in PPID+ equids as compared with aged (p < 0. 001) and young (p < 0.01) PPID- controls. In contrast, no differences were found in BMD of trabecular or cortical ROIs of MC3 and MT3 between groups. No differences were detected in force at fracture, displacement at fracture, Young's modulus or strain of L4 between PPID+ and aged PPID- horses. No differences were found in serum PTH, ionised Ca++ , 25-hydroxyvitamin D, or OC concentrations between groups. Limited number of equids studied and variation in test results. BMD of nonweight bearing bones can be decreased with PPID and could increase risk of developing pathological fractures.

Assessing spontaneous sensory neuron activity using in vivo calcium imaging.

Heightened spontaneous activity in sensory neurons is often reported in individuals living with chronic pain. It is possible to study this activity in rodents using electrophysiology, but these experiments require great skill and can be prone to bias. Here, we have examined whether in vivo calcium imaging with GCaMP6s can be used as an alternative approach. We show that spontaneously active calcium transients can be visualised in the fourth lumbar dorsal root ganglion (L4 DRG) through in vivo imaging in a mouse model of inflammatory pain. Application of lidocaine to the nerve, between the inflamed site and the DRG, silenced spontaneous firing and revealed the true baseline level of calcium for spontaneously active neurons. We used these data to train a machine learning algorithm to predict when a neuron is spontaneously active. We show that our algorithm is accurate in 2 different models of pain: intraplantar complete Freund adjuvant and antigen-induced arthritis, with accuracies of 90.0% ±1.2 and 85.9% ±2.1, respectively, assessed against visual inspection by an experienced observer. The algorithm can also detect neuronal activity in imaging experiments generated in a different laboratory using a different microscope configuration (accuracy = 94.0% ±2.2). We conclude that in vivo calcium imaging can be used to assess spontaneous activity in sensory neurons and provide a Google Colaboratory Notebook to allow anyone easy access to our novel analysis tool, for the assessment of spontaneous neuronal activity in their own imaging setups.

Chronological Changes in Sagittal Femoral Bowing after Primary Cementless Total Hip Arthroplasty: A Comparative 3D CT Study.

Little is known about dynamic changes of femoral anatomy after total hip arthroplasty (THA), in particular about sagittal femoral bowing (SFB). A 3D CT study was designed to evaluate the chronological changes of SFB after cementless femoral stem implantation for primary THA. Ten patients who underwent unilateral primary THA with a cementless femoral stem, with 2 consecutive CT scans (extending from the fourth lumbar vertebra to the tibial plateaus), performed before THA and at least 3 years after THA, were enrolled. The 3D models of femurs were created using image segmentation software. Using the two CT scans, SFB values of the proximal and middle thirds were calculated on the replaced and untreated sides by two different observers. Eight anatomical stems and two conical stems were involved. The post-operative CT was performed at an average follow-up of 6.5 years after THA (range: 3-12.5). The measurements performed by the two observers did not differ in the proximal and middle regions. A significant difference between the pre-operative and post-operative SFB compared to the untreated side was found in the proximal femur segment (p = 0.004). Use of a cementless stem in THA induced chronological changes in SFB of the proximal femur, after a minimum timespan of 3 years.

Total Hip Arthroplasty for Low-Grade Developmental Hip Dysplasia Changes the Ipsilateral Knee Alignment on the Axial and Coronal Planes

Background: There is a paucity of data regarding the post-operative influence of total hip arthroplasty (THA) on the axial and coronal alignments of the ipsilateral knee. A CT study was designed to assess the post-THA changes in axial and coronal knee alignments in low-grade dysplastic hips. Methods: Forty Crowe I–II dysplastic hips in 37 patients were assessed: a pre-operative CT scan from the fourth lumbar vertebra to the tibial plateaus was compared to a similar post-operative CT scan performed after a minimum of 2 years after THA. Results: THA implantation caused significant post-operative changes in terms of the rotation height (2 mm lowering; p = 0.003); center of rotation medialization (10 mm medialization; p &lt; 0.001); femoral offset (11 mm increase; p &lt; 0.001); femoral antetorsion (22° internal rotation; p &lt; 0.001), and hip internal rotation (9° internal rotation; p &lt; 0.001). The femoral axis angle deviated in the valgus (5.5° ± 1.1°, p &lt; 0.001) and the mechanical lateral distal femoral angle deviated in the varus (86° ± 2.7°, p = 0.001). The pelvic–tibial alignment changed from 88.2° ± 11.7° to 96° ± 9.3° (p &lt; 0.001). Patellar alignment was not influenced. Conclusions: In conclusion, THA imposes significant changes in low-grade dysplastic hips: all the modifications tend to neutralize the coronal alignment and, mostly, the rotational alignment, without substantial and durable variations of the patellofemoral joint. Large clinical trials should confirm whether radiological changes impact anterior knee pain and patellar stability.

AN UNCOMMON CASE OF FILUM TERMINALE HEMANGIOBLASTOMA NON-ASSOCIATED WITH VON HIPPEL – LINDAU DISEASE

A 55-year-old man presented with low backache, paraesthesia, and spasticity of both lower limbs. He had urinary retention and constipation. Investigations revealed a vascular intradural cauda equina tumor. MRI scan demonstrated an enhancing mass at the third and fourth lumbar vertebral levels. There were multiple dilated and tortuous veins draining from both poles of the tumor. At surgery, we found a well-defined tumor with an orange hue and fleshy consistency was encountered arising from the filum terminale, comprising a few adjacent nerve roots. The tumor was excised en bloc. The filum terminale was also been resected. A sporadic hemangioblastoma arising from the filum terminale should be considered as a rare cause of back pain and sciatica. Total excision of the tumor offers a cure.

Fourth lumbar artery continuation of the common iliac artery with a retro-psoas course demonstrated by CT.

To describe a case of an anomalous common iliac artery (CIA) arising from the aorta as the fourth lumbar artery (4th LA) and following a retro-psoas course as the continuation of the 4th LA. Contrast-enhanced abdominopelvic computed tomography (CT) findings of an incidentally detected anomalous CIA are described in an 8-year-old girl. CT showed that the right CIA originated from the distal aorta at the L3-L4 level with an acute angle and continued posteriorly in the course of the 4th LA. The right CIA descended into the iliac fossa as a single artery, lying posterior to the psoas muscle. It gave off the internal iliac artery (IIA) low in the iliac fossa and continued as the external iliac artery (EIA). The median sacral artery (MSA) originated from the left proximal CIA and joined the posterior division of the right IIA. Fourth LA continuation of the CIA is a rare vascular anomaly with a few published reports to date. The anomaly occurs far more on the right side than the left and is mostly asymptomatic. An abnormal connection between the umbilical artery and the distal aorta probably results in this anomaly, as well as in another group of CIA anomalies that are characterized by the absence of one or two CIAs with trifurcation or quadrifurcation of the distal aorta. Although the vascular anomaly is mostly asymptomatic, knowledge of it is important in the interventions of the area to prevent complications.

Screening for osteoporosis based on IQon spectral CT virtual low monoenergetic images: Comparison with conventional 120 kVp images

ObjectivesTo explore the differences between low kiloelectron volt (keV) virtual monoenergetic images (VMIs) using IQon spectral CT and conventional CT (120 kVp) in the diagnosis of osteoporosis. MethodsThis retrospective study included 317 patients who underwent IQon spectral CT and dual-energy X-ray absorptiometry (DXA) examination. Commercial deep learning–based software was used for the fully automated extraction of the CT values of the first to fourth lumbar vertebrae (L1–L4) from two different low-keV levels (including 40/70 keV) VMIs and conventional 120 kVp images. The DXA examination results served as the standard of reference (normal [T-score ≥ −1], osteopenia [-2.5 < T-score < −1], and osteoporosis [T-score < −2.5]). Osteoporosis diagnosis models were constructed using machine learning classifiers (logistic regression, support vector machine, random forest, XGBoost, and multilayer perceptron) based on the average CT values of L1–L4. The area under the receiver operating characteristic curve (AUC) and DeLong test were performed to compare differences in the performance of the osteoporosis diagnosis model between virtual low-keV VMIs and standard 120 kVp images. ResultsRandom forest-based prediction model obtained good overall performance among all classifiers, and macro/micro average AUC values of 0.820/840, 0.834/853, and 0.831/852 were obtained based on 40/70 keV and 120 kVp images, respectively. The model presented no significant difference between low-keV VMIs and standard 120 kVp images for the diagnosis of osteoporosis (p > 0.05). ConclusionsThe performance of the osteoporosis diagnosis model using IQon spectral CT simulating the low tube voltage scanning condition (less than 120 kVp) was also satisfactory. Bone density screening evaluation can be performed with a combination of low-dose lung scanning CT, greatly reducing the radiation dose without affecting the diagnosis.

A preliminary study on the effect of renal function on the metabolism of 18F-FDG in the human cerebellum.

The cerebellum is less affected by normal aging or neurodegenerative diseases, the aim of this paper is to investigate the effect of renal function status on uptake of 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG) in human cerebellum based on independent creatinine (CRE) or blood urea nitrogen (BUN) levels. A total of 253 patients who underwent 18F-FDG PET/CT scans were included. The patients were divided into groups according to renal function status: 201 patients with normal renal function, 16 patients with increase CRE, 36 patients with decrease CRE, and 31 patients with abnormal BUN. The maximum standardized uptake values were obtained in regions of interest (ROIs) for multiple tissue types (right cerebellum, right lobe of liver, right lung, bone marrow and psoas muscle at the level of the fourth lumbar vertebra). Moreover, the selected normal CRE groups were pair-matched with CRE decrease group with respect to age, sex, body mass index and glucose, respectively. Among 253 patients who met the inclusion/exclusion criteria, the final analysis included 967 ROIs (244 cerebellum, 191 lungs, 230 muscles, 145 bone marrow, and 157 liver) from 18F-FDG PET/CT scans. Among patients grouped by CRE or BUN levels, the uptake of 18F-FDG by cerebellum was significantly decreased in patients with CRE decrease level (P=0.001). There were no statistically significant differences between the other groups. Matched-pair analysis indicated there were no significant changes in outcomes between the CRE decrease group and the age-, sex-, BMI-, and glucose-matched controls compared to pre-matching. In patients with normal renal function and reduced CRE concentration, decrease cerebellar glucose metabolism was observed; however, no abnormal uptake of 18F-FDG was found in the cerebellum and other normal tissues of patients with impaired renal function. Consequently, in the study of cerebellar 18F-FDG metabolism, it may be necessary to consider the influence of blood CRE level.

Morphology and morphometry of the spinal cord and meninges in Egyptian Baladi goat (Capra hircus): Stereomicroscopy of blue-stained gray matter.

The study objective is to obtain normal morphology and morphometric data from Baladi goat spinal cord segments. Using Tompsett's technique for staining gray matter with a blue stain allowed us to calculate the quantity or area of gray and white matter and thus the total area of each segment. The spinal cord of the goat started at the extent of the middle-third of the occipital condyles, and the tapered end of the spinal cord terminated at the center of the first sacral vertebra. The total length of the spinal cord was 73.3 ± 2.5 cm on average. C3 was the longest spinal segment, measuring 3.95 cm. The gray matter area had a high value at the cervical and lumbar enlargements, with C8 having the highest value of gray matter cross sectional area at 12 mm2 and C7 having the highest value of white matter cross sectional area at 42 mm2 . The area of white matter of the cervical region was higher than that of the other spinal regions. At C7, the total cross section area reached its maximum of 53 mm2 . The cervical enlargement included segments from C6 to T1, while the lumbar enlargement included L5 to S1. The dura mater is connected cranially to the dens of the axis and caudally to the fourth and fifth lumbar vertebrae. The epidural space height between lumbar vertebrae was 2 mm in all lumbar spaces and 3 mm in the lumbosacral space. The normal morphology and morphometric data of the goat spinal cord segments may be useful in pathological conditions of the spinal cord and during epidural anaesthesia technique.

Pelvic insufficiency fractures after intensity modulated radiation therapy combined with chemotherapy for cervix carcinoma: Incidence and impact of bone mineral density

Background and PurposeThe aim of this study was to evaluate the incidence and predictive factors of Pelvic Insufficiency Fractures (PIFs) occurring after Intensity Modulated Radiation Therapy (IMRT) combined with chemotherapy for locally advanced cervical cancer (CC).Material and methodsMedical records of patients receiving radio-chemotherapy with IMRT between 2010 and 2020 for advanced CC were reviewed. PIFs were detected during follow-up on pelvic Magnetic Resonance Imaging (MRI) or Computed Tomography (CT). The cumulative incidence rate of PIFs and its confidence interval were calculated at 2 and 5 years of follow-up. Pre-therapeutic Bone Mineral Density (BMD) (g/cm3) was evaluated on CT simulation for sacrum and the fourth lumbar (L4) vertebrae. Sacrum dosimetric parameters (V30Gy, V40Gy, D50%, Dmean) were analyzed.Results136 patients were included. The median follow-up was 4.4 years. Median dose of D50% and V40Gy sacrum were 35.2 Gy (20.6–46.4) and 32.2% (7.2–73.4) respectively. The 2-year and 5-year cumulative incidence rates were 15.7% (95% CI: 9.88–22.71) and 22% (95% CI: 14.58–30.45) respectively. Median time interval between RT completion and PIFs’ detection was 11.5 months (IQR: 7.4–22.3). Univariate analysis showed that older age (p < 0.01), postmenopausal status at baseline (p < 0.01), and lower sacral and spinal BMD at baseline (respectively p < 0.001 and p < 0.01) were significantly associated to all sites of PIFs, and lower sacral BMD with sacral fractures (p < 0.001).ConclusionPost-IMRT PIFs were detected in 18.4% of patients with locally advanced CC. Individual predisposing factors as older age, postmenopausal status, decreased bone density on the CT simulation were mainly predictive.

Finite element analysis of lattice designed lumbar interbody cage based on the additive manufacturing.

Additive manufacturing (AM) methods, which facilitate the production of complex structures with different geometries, have been used in producing interbody cages in recent years. In this study, the effects of Ti6Al4V alloy interbody lattice designed fusion cages between the third and fourth lumbar vertebrae where degenerative disc diseases occur were investigated using the finite element method. Face centered cubic (FCC), body centered cubic (BCC), and diamond structures were selected as the lattice structure suitable for the interbody cage. A kidney shaped interbody lumbar cage was designed. The designated lattice structures were selected by adjusting the cell sizes suitable for the designed geometry, and the mesh configuration was made by the lumbar lattice structure. 400 N Axial force and 7.5 N.m moments were applied to the spine according to lateral bending, flexion, and torsion. 400 N axial force and 7.5 N.m flexion moment is shown high strain and total deformation then lateral bending and torsion on BCC FCC and diamond lattice structured interbody cages. In addition, the effects of lattice structures under high compression forces were investigated by applying 1000 N force to the lattice structures. When von Mises stresses were examined, lower von Mises stress and strains were observed in the BCC structure. However, a lower total deformation was observed in the FCC. Due to the design of the BCC and the diamond structure, it is assumed that bone implant adhesion will increase. In the finite element analysis (FEA), the best results were shown in BCC structures.

The Role of Magnetic Resonance Imaging in the Diagnosis of Spinal Dumbell Neurofibromatosis: A Case Report from a Specialist Hospital in Port Harcourt

Neurofibromatosis occurring in the spine also known as spinal neurofibromatosis (SNF) is a rare disease entity and they occur either unilaterally or bilaterally at the spinal roots. The low prevalence rate of the disease and scarcity of previous literatures is the main aim for this report.&#x0D; Our case study is a 29-years-old lady who presented to the Radiology department for a lumbosacral spine MRI, on account of both lower limb weakness, paresthesia, unsteady gait and finally inability to walk. The symptoms have been there since she was 14 years (15 years of progressive symptoms). She also presented with multiple macules on the skin (café au lait spots). Magnetic Resonance Imaging (MRI) of the lumbosacral spine revealed bilateral spinal neurofibromas at the spinal roots of the fourth lumbar vertebra to the sacral/coccygeal vertebrae with destruction of the sacro-coccygeal bones. MRI of the brain revealed no abnormalities in the brain and optic tract. The patient fulfilled the National Institutes of Health (NIH) criteria and that of revised diagnostic criteria for Neurofibromatosis (NF1).&#x0D; The patient also presented with lack of pain which could be due to impairment in sensory neurons. We describe a case of spinal neurofibromatosis diagnosed by MRI in a young lady with progressive lower limb weakness, paresthesia, sensory loss, café-au- lait spots and paraplegia.

Spectral parameters of gait differentiate diabetic patients from healthy individuals

BackgroundDiabetes mellitus (DM) is a clinical condition that affects gait performance and control in millions of individuals worldwide. Contrary to basic spatiotemporal parameters, gait-based spectral analysis may provide useful insights into gait neuromotor control. Hence, this study was set to investigate the spectral content of gait at the preferred speed in patients with DM. MethodsTotal 1117 individuals [658 DM and 649 healthy adults (HA)] performed a 10 m walk while wearing an inertial measurement unit over the fourth lumbar vertebra. Mann-Whitney-U test was used for between-group gait parameters comparisons. ResultsDM group had a slower step time (1.2%, p < 0.05) and gait speed (2.4%, p < 0.05) than HA. Additionally, DM individuals showed reduced dominant frequency (DM:0.24 Hz vs HA:0.25 Hz on average, p < 0.05). Increased antero-posterior and vertical dominant frequency width (DM:1.73 Hz vs HA:1.76 Hz on average, p < 0.05) and medio-lateral relative power spectral density at the dominant frequency (DM:6.19% vs HA:5.96%, p < 0.05). ConclusionsIt was demonstrated for the first time that the gait spectral content, not only corroborates spatiotemporal characteristics, but also provides further insight into their neuromotor control deficits in diabetic patients. Ultimately, this type of analysis in the diabetic population can help guide the therapeutic interventions to prevent diabetic foot.

Low bone mineral density is associated with fatty liver disease and respiratory illness in a pediatric mortality sample.

Chronic illness leads to decreased bone modeling and remodeling. This can be especially problematic during childhood and adolescence, since the majority of an individual's peak bone mass is achieved by the age of 20. In this study, we examine relationships between chronic illness and low bone mineral density (BMD) in a pediatric mortality sample (aged 0.5 to 20.9years) from New Mexico. We also test whether low BMD is related to decelerated linear growth by examining its relationship to growth stunting and arrest (Harris lines). Hounsfield units (HU), a proxy for trabecular BMD, were obtained at the fourth lumbar vertebra and the femoral neck from postmortem CT scans. Linear regression was used to examine associations between z-standardized HU and age, sex, medical conditions, Harris lines, and growth stunting. We find that lumbar HU is significantly lower for individuals with fatty liver disease and respiratory illness; femoral HU is significantly lower in individuals with Harris lines. The mechanisms of low BMD in individuals with fatty liver disease and respiratory illness are likely multifactorial and involve vitamin D deficiency (malnutrition, malabsorption), systemic inflammation, and sedentary lifestyles. However, better awareness of this relationship can provide clinicians with the ability to introduce nutritional and behavioral interventions early to mitigate deleterious effects on bone. Harris lines, on the other hand, mark temporary growth cessation due to physiological stress followed by a rapid resumption of growth. Low BMD in these individuals may be due to bone mineralization lagging behind relatively rapid linear growth.

Estimating age at death by Hausdorff distance analyses of the fourth lumbar vertebral bodies using 3D postmortem CT images.

The existing methods for determining adult age from human skeletons are mostly qualitative. However, a shift in quantifying age-related skeletal morphology on a quantitative scale is emerging. This study describes an intuitive variable extraction technique and quantifies skeletal morphology in continuous data to understand their aging pattern. A total of 200 postmortem CT images from the deceased aged 25-99years (130 males, 70 females) who underwent forensic death investigations were used in the study. The 3D volume of the fourth lumbar vertebral body was segmented, smoothed, and post-processed using the open-source software ITK-SNAP and MeshLab, respectively. To measure the extent of 3D shape deformity due to aging, the Hausdorff distance (HD) analysis was performed. In our context, the maximum Hausdorff distance (maxHD) was chosen as a metric, which was subsequently studied for its correlation with age at death. A strong statistically significant positive correlation (P < 0.001) between maxHD and age at death was observed in both sexes (Spearman's rho = 0.742, male; Spearman's rho = 0.729, female). In simple linear regression analyses, the regression equations obtained yielded the standard error of estimates of 12.5years and 13.1years for males and females, respectively. Our study demonstrated that age-related vertebral morphology could be described using the HD method. Moreover, it encourages further studies with larger sample sizes and on other population backgrounds to validate the methodology.

Stabbed to death: an osteobiography example of violence among Longobards (Povegliano Veronese, Italy, 6th-8th c CE)

Herewe report the reconstruction of the osteobiography of an adult male buried in the Longobard cemetery of Povegliano Veronese (Northern Italy, late 6th – early 8th century CE), who shows signs of interpersonal violence. The palaeopathological investigation reveals sharp force traumas on the body of the fourth lumbar vertebra and on two right ribs. The absence of signs of healing or bone remodelling indicates that the defects were perimortem. The injuries probably affected vital organs, leading to death. Further macroscopic observations of the skeleton suggest horseback-riding activity. Strontium isotope data from tooth enamel indicate a non-local origin of the individual. X-ray and CT scan acquisition and Scanning Electron Microscopy analyses were performed to investigate the bone defects. His osteobiography was interpreted and contextualised in the complex socio-political scenario of post-classical Italy. The results document that he spent his childhood outside the Povegliano Veronese area, that during his life he was likely a horseback rider active in battle, but that his violent death did not happen during warfare/battle. This multi-layered approach, supported by archaeological information, osteological investigation, biomolecular analysis, and virtual imagery, allowed for the extensive reconstruction of an individual's life history.

Association between periodontitis and disc structural failure in older adults with lumbar degenerative disorders: A prospective cohort study

BackgroundBacterial microbiome as a putative trigger of inflammation might indicate the cascade of mouth-gut-disc axis for causing intervertebral disc (IVD) structural failures (such as IVD degeneration and endplate change) processed. However, direct evidence for the mouth-gut-disc axis still unclear. Therefore, it is interesting to explore periodontal inflammation related to IVD structural failures and clinical outcomes.MethodsThis prospective cohort study enrolled older adults (aged ≥ 75 years) who scheduled to undergo elective open lumbar spine surgery. Demographic, radiological, clinical, and periodontal parameters were recorded. Independent samples t-test and Pearson’s correlation analysis were calculated.ResultsA total of 141 patients with lumbar degenerative disorders (56 males and 85 females; age 79.73 ± 3.34 years) were divided into edentulous group (19 patients), No/Mild group (84 patients), and Moderate/Severe group (38 patients). The incidence rates of IVD degeneration in each lumbar segmental level based on Pfirrmann grade and endplate change in the fourth and fifth lumbar vertebrae, and Visual Analogue Scale (VAS) low back pain (LBP) and leg pain of patients at preoperative in dentate group was significantly higher compared with edentulous group, especially the comparisons between Moderate/Severe and edentulous groups. There were no significant differences in the range of motion, lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, and disc height between dentate and edentulous groups. There was a positive association between plaque index (PLI) and pain scores (VAS LBP: r = 0.215, P = 0.030 and VAS leg pain: r = 0.309, P = 0.005), but no significant difference in Oswestry disability index (ODI) score.ConclusionResults show that the severity of periodontitis is associated with higher incidence rates of IVD degeneration and endplate change and clinical outcomes in older adults with lumbar degenerative disorders. Furthermore, the discovery of these relationships unveils a novel mechanism through which the alterations in oral microbiome composition potentially promote IVD degeneration and pain.

Biomechanical investigation of long spinal fusion models using three-dimensional finite element analysis

BackgroundThis study represents the first finite element (FE) analysis of long-instrumented spinal fusion from the thoracic vertebrae to the pelvis in the context of adult spinal deformity (ASD) with osteoporosis. We aimed to evaluate the von Mises stress in long spinal instrumentation for models that differ in terms of spinal balance, fusion length, and implant type.MethodsIn this three-dimensional FE analysis, FE models were developed based on computed tomography images from a patient with osteoporosis. The von Mises stress was compared for three different sagittal vertical axes (SVAs) (0, 50, and 100 mm), two different fusion lengths (from the pelvis to the second [T2-S2AI] or 10th thoracic vertebra [T10-S2AI]), and two different types of implants (pedicle screw or transverse hook) in the upper instrumented vertebra (UIV). We created 12 models based on combinations of these conditions.ResultsThe overall von Mises stress was 3.1 times higher on the vertebrae and 3.9 times higher on implants for the 50-mm SVA models than that for the 0-mm SVA models. Similarly, the values were 5.0 times higher on the vertebrae and 6.9 times higher on implants for the 100-mm SVA models than that for the 0-mm SVA models. Higher SVA was associated with greater stress below the fourth lumbar vertebrae and implants. In the T2-S2AI models, the peaks of vertebral stress were observed at the UIV, at the apex of kyphosis, and below the lower lumbar spine. In the T10-S2AI models, the peaks of stress were observed at the UIV and below the lower lumbar region. The von Mises stress in the UIV was also higher for the screw models than for the hook models.ConclusionHigher SVA is associated with greater von Mises stress on the vertebrae and implants. The stress on the UIV is greater for the T10-S2AI models than for the T2-S2AI models. Using transverse hooks instead of screws at the UIV may reduce stress in patients with osteoporosis.

Osteoporotic vertebral compression fractures caused by Cushing’s syndrome in young women: case report and literature review

BackgroundCushing’s syndrome is known as an important cause of secondary osteoporosis, characterized by reduction of bone mineral density and potential occurrence of fragility fractures before diagnosis in young population. Therefore, for young patients with fragility fractures, especially in young women, more attention should be paid on glucocorticoid excess caused by Cushing’s syndrome, due to relatively higher rate of misdiagnosis, distinct pathological characteristics and different treatment strategies compared with violent fractures and primary osteoporosis related fractures.Case presentationWe presented an unusual case of a 26-year-old woman with multiple vertebral compression fractures and pelvis fractures, subsequently diagnosed as Cushing’s syndrome. On admission, the radiographic results showed fresh second lumbar vertebra fracture, and old fourth lumbar vertebra and pelvic fractures. The dual energy X-ray absorptiometry of lumbar spine revealed marked osteoporosis, and her plasm cortisol was extremely high. Then, Cushing’s syndrome, caused by left adrenal adenoma, was diagnosed by further endocrinological and radiographic examinations. After receiving left adrenalectomy, her plasma ACTH and cortisol values returned to normal level. In term of OVCF, we adopted conservative treatments, including pain management, brace treatment, and anti-osteoporosis measures. Three months after discharge, the patient’s low back pain was in complete remission without new onset of pain, and returned to normal life and work. Furthermore, we reviewed the literatures on advancements in the treatment of OVCF caused by Cushing’s syndrome, and based on our experiences, proposed some additional perspectives to guide treatment.ConclusionIn term of OVCF secondary to Cushing’s syndrome without neurological damage, we prefer systematic conservative treatments, including pain management, brace treatment, and anti-osteoporosis measures, to surgical treatment. Among them, anti-osteoporosis treatment has the highest priority because of the reversibility of osteoporosis caused by Cushing’s syndrome.

A novel method to estimate adult age from the lumbar vertebral body using 3D PMCT images in Japanese

This study evaluated the age-related changes in the vertebral body using 3D Postmortem CT (PMCT) images and proposed an alternative age estimation formula. The PMCT images of 200 deceased individuals aged 25 to 99 years (126 males, 74 females) were retrospectively reviewed and included in the study. Using the open-source software ITK-SNAP and MeshLab, a 3D surface mesh of the fourth lumbar vertebral body (L4) and its convex hull models were created from the PMCT data. Using their inbuilt tools, volumes (in mm3) of the L4 surface mesh and convex hull models were subsequently computed. We derived VD, defined as the difference in volumes between the convex hull and L4 surface mesh normalized by L4 mesh volume, and VR, defined as the ratio of L4 mesh volume to convex hull volume based on individual L4. Correlation and regression analyses were performed between VD, VR, and chronological age. A statistically significant positive correlation (P < 0.001) between chronological age and VD, (rs = 0.764, males; rs = 0.725, females), and a significant negative correlation between chronological age and VR (rs = -0.764, males; rs = -0.725, females) was obtained in both sexes. The lowest standard error of the estimate was demonstrated by the VR at 11.9 years and 12.5 years for males and females, respectively. As such, their regression models to estimate adult age were Age = 248.9–2.5VR years, males; Age = 258.1–2.5VR years, females. These regression equations may be useful for estimating age in Japanese adults in forensic settings.