L5 Lumbar Research Articles

Percutaneous Decompression and Fixation on Complex Spinal Metastases

Materials and Methods Retrospectively analyzed the postoperative results of a series of 6 patients with vertebral metastases, with complicated mechanical pain and neurological involvement using a decompression technique and percutaneous fixation. Discuss the results with the literature. Results Total of 6 cases, 3 men and 3 women. Average age: 67.8 years (66–85), all with known primary tumor: 2 lungs tumor, 2 breast tumor, 1 prostate tumor and 1 renal tumor. Neurological compromise: L5 radicular pain paresis and one progressive thoracic myelopathy. SINS: 8,9,10,12,13,13. Tomita: 3,5,5,6,10,10. Surgical technique: posterolateral decompression, tube 5 Kapener decompression tube type 1, all percutaneous pedicle fixation. Complications: 1 patient L5 lumbar epidural hematoma resolved with surgical evacuation. Five of six went to early radiotherapy Evolution: In all of them neurological recovery and relief of mechanical and radicular pain. Conclusions Conventional treatment of patients with neurologic involvement secondary to vertebral metastasis is surgical decompression and open setting, this depending on the vital prognosis and patient status as mayor surgeries. The high rate of complications and fixing decompression percutaneous seem to offer an effective alternative in the management of the complication with minimal complications.

Neurological Recovery in Two Patients with Cauda Equina Syndrome Secondary to L5 Lumbar Spine Giant Cell Tumour after Treatment with Denosumab without Surgery.

We report two patients with cauda equina syndrome (CES) secondary to L5 giant cell tumour (GCT) who achieved good neurological recovery after treatment with denosumab without surgery. The first patient was a 26-year-old man with L5 GCT causing CES who regained bowel and urinary control, muscle power improvement from grade 2 to grade 4 and Oswestry disability index (ODI) improvement from 48 to 23 after denosumab treatment. The second patient was a 25-year-old woman with L5 GCT causing CES who regained bowel and urinary control, muscle power improvement from grade 0 to grade 4 and ODI improvement from 42 to 20 after denosumab treatment. The usage of denosumab in the treatment of patients with CES due to GCT allows potential neurological recovery without any surgical intervention. If surgery is not contraindicated, more time is obtained to prepare the patient preoperatively to attain safer surgery and to achieve complete tumour clearance.

Diagnosis of Lumbar Foraminal Stenosis using Diffusion Tensor Imaging.

Diagnosis of lumbar foraminal stenosis remains difficult. Here, we report on a case in which bilateral lumbar foraminal stenosis was difficult to diagnose, and in which diffusion tensor imaging (DTI) was useful. The patient was a 52-year-old woman with low back pain and pain in both legs that was dominant on the right. Right lumbosacral nerve compression due to a massive uterine myoma was apparent, but the leg pain continued after a myomectomy was performed. No abnormalities were observed during nerve conduction studies. Computed tomography and magnetic resonance imaging indicated bilateral L5 lumbar foraminal stenosis. DTI imaging was done. The extraforaminal values were decreased and tractography was interrupted in the foraminal region. Bilateral L5 vertebral foraminal stenosis was treated by transforaminal lumbar interbody fusion and the pain in both legs disappeared. The case indicates the value of DTI for diagnosing vertebral foraminal stenosis.

Sacral Stress Fracture following the Bone Union of Lumbar Spondylolysis.

While 22 articles have reported on sacral stress fractures, it is a rare injury and its etiology is not well known. We present the case of a 16-year-old male who presented with low back pain in 2015. He was a high school soccer player with a previous history of a bilateral L5 lumbar spondylolysis in 2014. The patient refrained from soccer and wore a brace for six months. Two months after restarting soccer, he again complained of low back pain. After 1 year, a lumbar spine computed tomography revealed the bone union of the spondylolysis. At his first visit to our hospital, his general and neurological conditions were normal and laboratory data were within the normal range. Sacral coronal magnetic resonance imaging (MRI) of the left sacral ala revealed an oblique lineal signal void surrounding bone marrow edema. Based on his symptoms, sports history, and MRI, he was diagnosed with a sacral stress fracture. He again refrained from soccer; his low back pain soon improved, and, after 1 year, the abnormal signal change had disappeared on sacral MRI. Recurrent low back pain case caused by a sacral stress fracture occurring after the bone union of lumbar spondylolysis is uncommon.

Elevated CCL2/MCP-1 Levels are Related to Disease Severity in Postmenopausal Osteoporotic Patients.

Chemokine (C-C) ligand-2 (CCL2), also named monocyte chemoattractant protein 1 (MCP-1), is an important chemotactic factor involved in a wide range of diseases. Recent studies have shown that CCL2/MCP-1 plays crucial roles in the osteoclastogenic process. The current study was performed to measure serum CCL2 levels in postmenopausal osteoporotic patients and investigate the relationship between CCL2 concentrations in serum and disease severity in postmenopausal osteoporotic patients. A total of 62 postmenopausal osteoporotic female patients (PMOP group), 68 postmenopausal non-osteoporotic female patients (PMNOP group), and 65 healthy women of childbearing age (Control group) were enrolled in the study. The calcaneal quantitative ultrasound was utilized to conduct bone mineral density (BMD) measurements, confirmed at the left femoral neck, greater trochanter, total hip, and L1 - L4 lumbar spine by dual energy X-ray absorptiometry (DXA). Serum CCL2, TNF-α as well as IL-6 levels were measured with enzyme-linked immunosorbent assay. Estrogen-2 (E2) was measured with radioimmunoassay. The Visual Analogue Scores (VAS) was utilized to assess the extent of pain in PMOP. We demonstrated for the first time that CCL2 levels were increased in postmenopausal women compared with controls. We also found that elevated CCL2 levels were linked with decreased BMD and attenuated E2 concentrations. In addition, CCL2 levels were positively correlated with inflammation markers TNF-α, IL-6, and VAS scores. CCL2 in serum serves as a potential biomarker for reflecting disease severity in postmenopausal osteoporotic patients. Therapeutic interventions that target CCL2 and its related signaling pathways in order to delay osteoporosis development deserve further study.

Visualization of Lumbar Artery Variations by Contrast-Enhanced Multi-detector Row Computed Tomography.

This study was designed to identify the anatomical variations of lumbar arteries on contrast-enhanced multi-detector row computed tomography (MDCT). Consecutive 100 colon cancer patients underwent preoperative 3-dimensional navigation studies, which include CT colonography (CTC) and CT angiography (CTA) for evaluation of anatomical relationship between the colon cancer and mesenteric vasculatures. After exclusion of inappropriate cases, 84 cases (33 women and 51 men; mean age, 64 years) were finally analyzed. The visualization of lumbar arteries from the CTA was scored based on the agreement of two radiology specialists. Also the presence or absence of left and right common trunk of each lumbar artery was evaluated. Visualization scores on both sides of L1 were significantly lower than those of L2-L4. No significant difference could be found on visualization of L1 lumbar arteries between the young and the elderly group. The common trunk tended to be in the lower lumbar levels (L1 in 2.4%, L2 in 9.5%, L3 in 11%, and L4 in 23%). The development and variation of lumbar arteries can be evaluated with CTA. Furthermore, CTA can provide sufficient anatomical information on variations of the lumbar arteries prior to surgery or catheterization.

The diagnosis of double-crush lesion in the L5 lumbar nerve using diffusion tensor imaging

Background ContextA double-crush lesion is a condition in which the lumbar nerve is compressed both medially and laterally in the spinal canal, where diagnosis can be very difficult, and is a factor leading to poor surgical success rates. PurposeDiffusion tensor imaging (DTI) was used to determine DTI parameter fractional anisotropy (FA) values and apparent diffusion coefficient (ADC) in both intraspinal column lesions alone and in double-crush lesions. Study DesignThis study used a prospective study. Patient SampleOf the 56 cases (mean age: 72.2 years) that underwent laminectomy for lumbar spinal stenosis at our clinic between April 2013 to March, 2015, 10 cases with L5 radiculopathy caused by L4–L5 stenosis (Intraspinal stenosis group (Group I); mean age: 74.7 years), and 5 cases with persistent symptoms caused by L5 foraminal stenosis despite L4–L5 decompression surgery (Double-crush group (Group D); mean age: 77.6 years) were targeted. One patient in Group D was diagnosed through microendoscopic intrapedicular partial pediculotomy and the remaining four cases by nerve root infiltration. Five healthy cases (mean age: 54 years) were studied as controls. Outcome measuresIntraspinal zone (Iz), nerve root (N), and extraforaminal zone (Ez) were established as the regions of interest, and the L5 nerve FA and ADC values were determined on the affected side. MethodsDiffusion tensor imaging was performed prospectively by 1.5T magnetic resonance imaging before surgery, and DTI parameters of L5 nerve were evaluated in all patients and healthy volunteers. Student t test was used for group comparisons, and a p<.05 was considered statistically significant. ResultsFractional anisotropy values (Iz, N, Ez) were 0.415, 0.448, and 0.517, respectively, increasing as sites became more distal. Group I values were 0.335, 0.393, and 0.484, and Group D values were 0.296, 0.367, and 0.360. Compared with the healthy volunteers, Group D had significantly lower Iz (p<.05) and Ez (p<.001) values, while Group I had significantly lower Iz (p<.05) values. In Group D, Ez FA values were significantly lower (p<.001) than in Group I. Apparent diffusion coefficient values (Iz, N, Ez) in the healthy control group were 1.270 mm2/s, 1.151 mm2/s, and 0.937 mm2/s with values decreasing as sites grew distal. In Group I, the ADC values were 1.406 mm2/s, 1.184 mm2/s, and 1.001 mm2/s, while in Group D they were 1.551 mm2/s, 1.412 mm2/s, and 1.329 mm2/s. Compared with the healthy volunteers, Iz (p<.05) and Ez (p<.05) values were significantly higher in Group D. The N (p<.01) and Ez (p<.001) ADC values were significantly higher in Group D than in Group I. ConclusionsDepending on where the nerve was compressed, changes in DTI parameters revealed nerve damage (low FA values and increased ADC) in the intraspinal canal in the Intraspinal Group, and over a widespread area in the Double-crush Group spanning the medial to lateral spinal canal. Our research suggests that in cases where double crush is suspected before surgery, failed back surgery syndrome may be prevented by evaluating DTI images.

Associations of Computed Tomography-Based Trunk Muscle Size and Density With Balance and Falls in Older Adults.

Deficits in balance and muscle function are important risk factors for falls in older adults. Aging is associated with significant declines in muscle size and density, but associations of trunk muscle size and density with balance and falls in older adults have not been previously examined. Trunk muscle size (cross-sectional area) and attenuation (a measure of tissue density) were measured in computed tomography scans (at the L2 lumbar level) in a cohort of older adults (mean ± SD age of 81.9±6.4) residing in independent living communities. Outcome measures were postural sway measured during quiet standing and Short Physical Performance Battery (SPPB) at baseline, and falls reported by participants for up to 3 years after baseline measurements. Higher muscle density was associated with reduced postural sway, particularly sway velocities, in both men and women, and better Short Physical Performance Battery score in women, but was not associated with falls. Larger muscle size was associated with increased postural sway in men and women and with increased likelihood of falling in men. The results suggest that balance depends more on muscle quality than on the size of the muscle. The unexpected finding that larger muscle size was associated with increased postural sway and increased fall risk requires further investigation, but highlights the importance of factors besides muscle size in muscle function in older adults.

A Biomechanical Comparison of Shape Design and Positioning of Transforaminal Lumbar Interbody Fusion Cages

Study Design Cadaveric biomechanical analysis.Objective The aim of this study was to compare three interbody cage shapes and their position within the interbody space with regards to construct stability for transforaminal lumbar interbody fusion.Methods Twenty L2–L3 and L4–L5 lumbar motion segments from fresh cadavers were potted in polymethyl methacrylate and subjected to testing with a materials testing machine before and after unilateral facetectomy, diskectomy, and interbody cage insertion. The three cage types were kidney-shaped, articulated, and straight bullet-shaped. Each cage type was placed in a common anatomic area within the interbody space before testing: kidney, center; kidney, anterior; articulated, center; articulated, anterior; bullet, center; bullet, lateral. Load-deformation curves were generated for axial compression, flexion, extension, right bending, left bending, right torsion, and left torsion. Finally, load to failure was tested.Results For all applied loads, there was a statistically significant decrease in the slope of the load-displacement curves for instrumented specimens compared with the intact state (p < 0.05) with the exception of right axial torsion (p = 0.062). Among all instrumented groups, there was no statistically significant difference in stiffness for any of the loading conditions or load to failure.Conclusions Our results failed to show a clearly superior cage shape design or location within the interbody space for use in transforaminal lumbar interbody fusion.

One-stage posterior spinal shortening by L5 partial spondylectomy for spondyloptosis or L5–S1 high-grade spondylolisthesis management

A case series of seven consecutive patients with L5-S1 spondyloptosis (SPP) and Meyerding IV spondylolisthesis (HGSPL) treated consecutively by a new surgical technique with partial reduction and fixation after spinal shortening. To report clinical and radiological outcomes of a spinal shortening procedure by a single posterior approach in seven patients with HGSPL and SPP. The surgical treatment of L5-S1 SPP and HGSPL remains challenging, and numbers of surgical treatment options have been described with several principles. We reported a new surgical technique achieving partial reduction and fixation of L5-S1 SPP and HGSPL and highlighted its clinical and radiological outcomes. Seven patients with Meyerding Grade IV (2), and Grade V (5) were operated consecutively between 2004 and 2011 for HGSPL and SPP. Surgery time, blood loss and complications were collected for all patients. The slip angle or Dubousset lumbo-sacral Angle (Dub-LSA), L5 slip percentage (%slip), pelvic tilt (PT), lumbar lordosis (LL), thoracic kyphosis (TK) and C7-tilt were measured pre and postoperatively. All patients underwent posterior one-stage decompression with sacral dome osteotomy, L5 vertebrectomy with L5-S1 discectomy, and partial reduction and instrumented fusion in a single posterior approach. The mean age and follow-up were, respectively, 20 years and 65 months. The mean preoperative %slip was 115 %, which improved to 63 % postoperatively. The mean preoperative Dub-LSA, PT, LL, TK, and C7-tilt were 37°, 31°, -74°, 30°, and 6°, respectively, which improved to 94°, 25°, -44°, 42° and -0.14° postoperatively. No implant failure or pseudarthrosis were reported at last follow-up. This novel and efficient one-stage shortening technique offers the possibility to manage lumbosacral kyphosis and spinal local malalignment in L5-S1 SPP.

Anti-osteoporosis effects of 1,4-dihydroxy-2-naphthoic acid in ovariectomized mice with increasing of bone density

Objective1,4-Dihydroxy-2-naphthoic acid (DHNA) is the main component of the metabolic products after fermentation by Propionibacterium freudenreichii ET-3. In this study, DHNA, vitamin K2 (VK2), and risedronate (Ris) were administered to ovariectomized (OVX) mice to ascertain their suppressive effects on bone mass reduction. MethodsFifty mice were divided into five groups: Sham, OVX, DHNA, VK2, and Ris groups. The drugs were administered daily for 8 weeks. Subsequently, blood was collected from the orbital venous plexus. The bilateral femurs and L5 lumbar vertebra were excised. To determine the effects of the drugs, we performed histomorphometric analyses of the left femur and L5 by micro-CT, biochemical analyses of serum samples, and histological analyses of the right femur. ResultsThe results for the total bone mineral density, bone volume density, trabecular thickness, trabecular number, trabecular separation, and histological analyses showed that bone resorption was improved in the DHNA and Ris groups compared with the OVX group. Furthermore, the biochemical analyses revealed that the production of inflammatory cytokines was suppressed in the DHNA and Ris groups. ConclusionsThe present findings show that DHNA suppresses the bone mass reduction in OVX mice, suggesting that it could be an alternative treatment for postmenopausal osteoporosis.

A study of sacral anthropometry to determine S1 screw placement for spinal lumbosacral fixation in the Korean population.

1. To investigate the incidence of closed-type PSIS in the Korean population. 2. To categorize the morphological features of Korean sacrum. 3. To measure the safe marginal length and angle for screw fixation considering the PSIS and course of the external iliac vein, using a Korean sacrum model. We performed our study in 160 sacra including the pelvic ring obtained from 80 Korean cadavers. The bony measurements were obtained by performing 1-mm computed tomography cuts from the L5 lumbar vertebra to the pelvic ring and excluding other structures. We evaluated the incidence of anatomic variation of the PSIS and measured the safe marginal length and angle for screw fixation considering the PSIS and course of the external iliac vein, using a Korean sacrum model. Our study showed that the closed type of PSIS is more frequent in males than in females. The optimal angle for screw fixation is 16.91 ± 6.85 (°), while the left side S1 pedicle insertion angle is 16.00 ± 6.20 (°). The average Korean optimal screw length is 58.35 ± 14.90 (cm) for the right side and 55.89 ± 16.16 (cm) for the left side. With reference to these parameters, the optimal screw length and angle can be chosen and bicortical anteromedial screw fixation can be easily and safely performed.

Apex of deformity for three-column osteotomy. Does it matter in the occurrence of complications?

BackgroundPosterior vertebral column resection (PVCR) is a challenging but effective technique for the correction of complex spinal deformity. However, it has a high complication rate and carries a substantial risk for neurologic injury. PurposeThe aim was to test whether the apex of the deformity influences the clinical outcomes and complications in patients undergoing PVCR. Study designA historical cohort was recruited from a single center and evaluated preoperatively, postoperatively, and at final follow-up. Patient sampleNinety-eight hyperkyphotic patients undergoing PVCR were included. Inclusion criteria consisted of kyphoscoliosis and hyperkyphosis surgically treated with PVCR as a primary or revision procedure. Outcome measuresThe outcome measures included a number of neurologic complications. MethodsReceiver operator characteristic (ROC) curve analysis and Youden index (J) were used to estimate the optimum cut-off to predict neurologic complications for each potential risk factor. In three ROC analyses, we included separately body mass index (BMI), kyphosis degree, and age as independent variables and neurologic complications as the dependent variable. Logistic regression was used to estimate the odds ratios (ORs) and construct 95% confidence intervals (CIs). ResultsAmong the 98 patients, the etiologies were: post infectious (50), congenital (31), and others (17). The averages were: age 14±6.5 years, BMI 20±10 kg/m2, American Society of Anesthesiologists 3±0.7, forced vital capacity 76±23%, fusion levels 10±3, estimated blood loss 1,319±720 mL, surgical time 375±101 minutes, and preoperative localized kyphosis 104±30°. Thirty-three patients had abnormal preoperative neurologic status. Major complications occurred in 46 patients (neurologic in 25). The apex of kyphosis was proximal thoracic T1–T5 (five patients), thoracic (TH) T6–T9 (17 patients), thoracolumbar T10–L2 (55 patients), and lumbar L3–S1 (nine patients). The level of apex and BMI were independent risk factors for neurologic complications: TH apex (OR: 101.30, 95% CI: 1.420–infinite; p=.037); BMI (OR: 1.92, 95% CI: 1.110–infinite; p=.026). ConclusionsPosterior vertebral column resection for severe spine deformity is technically demanding and carries a substantial risk. The apex is a variable that influences the occurrence of neurologic complications, and the presence of a TH apex in particular could be a preoperative risk factor for neurologic complications.

Renal scarring and chronic kidney disease in children with spina bifida in a multidisciplinary Malaysian centre.

The aim of this study was to determine the occurrence of renal cortical scarring and chronic kidney disease (CKD) in children with neurogenic bladder secondary to spina bifida (SB) managed at the Universiti Kebangsaan Malaysia Medical Centre. The secondary objective was to identify the clinical factors associated with these adverse outcomes. The medical records of 56 children managed from 1997 were available. Socio-demographic and clinical data for SB children managed for a minimum of 2 years (n = 45) were reviewed. This included age at referral, gender, ethnicity, duration of care, type of SB lesion, presence of vesico-ureteric reflux (VUR), symptomatic urinary tract infections, bladder trabeculation, catheterisations and renal function. Forty-nine per cent of SB lesions were open myelomeningocoele, 40% were closed lesions and 11% were occult. Majority (96%) were at lumbar L3 or below. Twenty-nine children (64.5%) were referred before 6 months of age (mean15.8 months; range newborn to 125 months). Thirty-five (77.8%) had neurogenic bladder and 31(69%) had neurogenic bowel. Sixteen developed renal scarring and six, CKD. Late referral (≥6 months of age), small kidneys at referral, dilating VUR and bladder trabeculation were significant independent factors associated with scarring. On multivariate analysis, late referral (odds ratio (OR) 17.4; 95% confidence interval (CI) 1.26-238.7) and dilating VUR (OR 137.0; CI 6.4-2921.1) remained significant. Prevention of renal scarring and CKD remains a challenge in Malaysia even with multidisciplinary proactive care of SB children. Early referrals and more stringent management strategies for dilating VUR are still required.

Using finite element modeling to predict the positions of L4-5 lumbar disc decompression

Using finite element modeling to predict the positions of L4-5 lumbar disc decompression

Aseptic Spondylodiscitis after Lumbar Discectomy: Case Report and Literature Review

Introduction Aseptic inflammatory changes in the vertebral bone marrow, end plates and intervertebral discs have been described as part of different entities such as Modic changes (MCs). MCs are classified in three types according to the formation of vascularized fibrous, fatty, or cicatricial bone tissue. Radiologically, each type is distinguished by particular magnetic resonance imaging (MRI) findings. MCs can be seen as part of normal spinal degeneration or secondary to spine surgical procedures such as lumbar discectomy. Even though their prevalence varies between studies, in clinical practice they generally are infrequent radiological findings. Patient and Methods: A case report of a 26-year-old man with 10 days of postoperative intense low back pain refractory to oral analgesia after L4–L5 lumbar discectomy is presented. A nonsystematic literature review about postoperative MCs was conducted. Results The patient evolved with difficult pain management needing to be hospitalized and studied with laboratory examinations and spinal images. Elevation of inflammatory parameters and lumbar spine MRI with T1-weighted image hypointensity, T2-weighted image hyperintensity, and increased signal with gadolinium at vertebral bone marrow and end plates adjacent to L4–L5 disc were the main findings. Septic spondylodiscitis was suspected as differential diagnosis, but conservative treatment was followed by clinical observation and evaluation of inflammatory parameters. The patient evolved with a progressive decrease of back pain and slight elevation of control inflammatory parameters but neither antibiotic treatment nor surgery was needed. At 9th day of hospitalization, the patient was discharged given positive clinical response with no pain at rest and slight pain with movement. Ambulatory follow-up with laboratory and imaging study exhibited normalization of inflammatory parameters and resolution of vertebral bone marrow and end plates changes accompanied by remission of patient's pain. Conclusion MCs are infrequent radiological findings. Type 1 MCs show similar MRI findings to those seen in the infectious process of the spine, which turns septic discitis/spondylodiscitis the main differential diagnosis to discard. When MCs are present, laboratory and imaging evaluation has to be performed to rule out an infectious etiology. Evaluation of inflammatory parameters, diffusion-enhanced MRI, and analysis of MRI contrast enhancement patterns are useful tools for this purpose. Because of the significant association between MCs and low back pain, symptomatic MCs must be treated with a first-line conservative treatment of analgesia and physical activity restriction.

The Factors Affecting Bone Density in Cirrhosis

Background:Bone loss is common in cirrhosis. However, the prevalence of osteopenia and osteoporosis has been heterogeneous in different reports. Reduction in bone formation with or without increase in bone resorption appears to be responsible for bone loss in these patients.Objectives:We aimed to investigate bone loss in patients with cirrhosis at different anatomical sites and key factors that might affect it.Patients and Methods:In this cross-sectional study, 97 patients with cirrhosis who were referred to Razi Hospital, Rasht, Iran, from 2008 to 2010, were studied. Cirrhosis was diagnosed using biopsy and/or clinical and paraclinical findings. Bone mineral densitometry was done in L2 through L4 lumbar spine (LS) and femoral neck (FN), using dual-energy X-ray absorptiometry (DEXA) (QDR 1000, Hologic DEXA Inc, Waltham, Massachusetts, the United States). Statistical analysis was performed using SPSS 18. A P value < 0.05 was considered statistically significant.Results:A total of 97 patients with cirrhosis (55.7% male) and the mean age of 51 ± 13 years and median body mass index (BMI) of 22.7 kg/m2 were recruited over a two-year period. Etiologies of cirrhosis were hepatitis C (40.2%), hepatitis B (26.8%), cryptogenic (21.6%), and other causes (11.4%). Child A, B, and C, were seen in 16.5%, 47.4%, and 36.1% of patients, respectively. The DEXA results were abnormal in 78.4% of our participants (osteopenia, 45.4%; osteoporosis, 33%). BMI and calculated glomerular filtration rate (GFRc) had moderate positive and Child score had moderate negative significant correlation with T score in both anatomical sites. There was no significant association between abnormal DEXA and the causes of cirrhosis. The univariate analysis showed that the risk of abnormal results in DEXA was significantly higher in those with low BMI, current smoking, higher Child score, and low GFRc; however, in multivariate analysis, the abnormal results were more frequent in those with lower vitamin D, higher Child score, and less GFRc.Conclusions:Abnormal DEXA was highly prevalent among patients with cirrhosis. The risk of this finding was increased by lower vitamin D levels, advanced disease, and impaired renal function.

Characterising bone material composition and structure in the ovariectomized (OVX) rat model of osteoporosis.

The ovariectomized (OVX) rat model is well established in investigations of osteoporosis and osteoporotic therapies. Advent of techniques such as Fourier-transform infrared (FTIR) spectroscopy and small angle X-ray scattering (SAXS) facilitate characterization of bone composition and mineral structure, respectively, which are key determinants of bone strength. Limited publications exist on the implementation of these techniques in the OVX rat model. At 12 weeks of age, female Sprague-Dawley rats were either sham-operated (n = 6) or ovariectomized (n = 6) and sacrificed 18 weeks later. L2 lumbar vertebrae and proximal tibiae were assessed by µCT, FTIR and SAXS. Presence of extensive trabecular deterioration in the µCT data confirmed the onset of osteoporosis. FTIR compositional parameters were determined including measures of degree of mineralization, crystallinity, collagen maturity and acid phosphate content. Mineral crystal thickness was determined from the SAXS data using two approaches available in literature. Compositionally, a decline in the heterogeneity of acid phosphate content was observed while measures of crystallinity and collagen maturity remained unaltered. Using an iterative curve fitting method, OVX-induced increases in the mineral crystal thickness of 3.8 and 7.8 % (p < 0.05) were noted in the trabecular of the vertebra and tibia, respectively. In conclusion, implementation of FTIR and SAXS techniques in the OVX rat model, identified no significant compositional changes while substantiating thickening of the mineral crystals as a general structural feature of OVX-induced osteoporosis in rats.

Relationship of vitamin D status and bone mass according to vitamin D-binding protein genotypes.

BackgroundVitamin D-binding protein (DBP) may alter the biological activity of total 25-hydroxyvitamin D [25(OH)D]; this could influence on the effects of vitamin D in relation to bone mineral density (BMD) and fractures. Emerging data suggest that fetuin-A may be involved in bone metabolism. We aimed to investigate the influence of DBP gene polymorphism on the relationship of vitamin D status and fetuin-A levels to BMD and bone markers.MethodsThis cross-sectional study was part of a health survey of employees of the Electricity Generating Authority of Thailand (1,734 healthy subjects, 72% male). Fasting blood samples were assayed for 25(OH)D, fetuin-A, N-terminal propeptides of type 1 procollagen (P1NP), C-terminal cross-linking telopeptides of type I collagen (CTx-I), and DBP rs2282679 genotypes. L1–L4 lumbar spine and femoral BMD were measured using dual-energy X-ray absorptiometry.ResultsThe DBP rs2282679 genotype distribution conformed to the Hardy–Weinberg equilibrium. There were no correlations between 25(OH)D levels and BMD and bone markers. But a trend of positive correlation was observed for the DBP genotypes with total hip BMD, and for the interaction between 25(OH)D and DBP genotypes with BMD at all femoral sites. We further analyzed data according to DBP genotypes. Only in subjects with the AA (common) genotype, 25(OH)D levels were positively related to BMD and bone markers, while fetuin-A was negatively related to total hip BMD, independently of age, gender and BMI.ConclusionsThe interaction between vitamin D status, as measured by circulating 25(OH)D and DBP rs2282679 genotypes, modified the association between 25(OH)D and BMD and bone markers. Differences in DBP genotypes additionally influenced the correlation of fetuin-A levels with femoral BMD.Electronic supplementary materialThe online version of this article (doi:10.1186/s12937-015-0016-1) contains supplementary material, which is available to authorized users.

Worksite back and core exercise in firefighters: Effect on development of lumbar multifidus muscle size

Firefighting is a dangerous occupation with a high incidence of low back pain and injury. Abnormal back muscle function and morphology has been linked to low back pain and poor physical performance. The effect of exercise training on back muscle size and symmetry has not been investigated in firefighters. The purpose of this study was to assess the effect of worksite exercise training for eliciting lumbar multifidus muscle hypertrophy in firefighters. A cluster randomized controlled trial was conducted with healthy, career firefighters (n=64) from a medium-sized fire department. Participants were randomized by fire station to exercise training (n=36) (supervised back and core exercise performed on duty, 2X/week, 24 weeks) or control (n=28). The cross-sectional area (CSA) of the L4 and L5 lumbar multifidus muscle was assessed with ultrasonography at baseline and following the intervention. At 24 weeks, no significant differences were noted between the groups in the adjusted (by baseline scores and body mass) L4 and L5 lumbar multifidus muscle CSA and asymmetry values. A worksite exercise training program targeting the back and core is not effective for eliciting hypertrophy of the lumbar multifidus muscle in healthy firefighters.