Lumbar Spine L1 Research Articles

Guidelines for diagnostics and treatment of aromatase inhibitor-induced bone loss in women with breast cancer: A consensus of Lithuanian medical oncologists, radiation oncologists, endocrinologists, and family medicine physicians

The aim of this article is to inform about cancer treatment-induced bone loss, to identify patients at risk and those that can benefit from bone targeted treatment as well as highlight the importance of the multidisciplinary approach in the bone health in cancer care. Patients with breast cancer treated or intended to be treated with aromatase inhibitors belong to a high-risk group because their fracture risk increases up to 30% due to a significant decrease in bone mineral density within 6–12 months after the start of hormonal treatment. To evaluate bone status and predict risk for fractures, lateral thoracic and lumbar spine X-ray imaging, bone mineral density measurement by dual energy X-ray absorptiometry at the lumbar spine L1–L4 vertebrae and/or hip and fracture risk factors assessment are mandatory tests prior to hormonal treatment. Morbidity and mortality associated with bone loss can be prevented with appropriate screening, lifestyle interventions, and therapy. Algorithm for the management of bone health in breast cancer patients was established in Lithuania to screen patients with increased risk for bone loss and to provide adequate specific osteoporosis treatment.

Aging changes in lumbar discs and vertebrae and their interaction: a 15-year follow-up study

Background contextMany studies have focused on either the intervertebral disc as a culprit in back pain problems, or the vertebral body, but very few studies have examined both structures and their relationship. PurposeTo measure the concordant changes in morphology of the discs and vertebrae during 5-, 10-, and 15-year follow-ups. Study designLongitudinal study. Patient sampleAmong a general population sample of 232 men that had been scanned in 1992–1993, 105 men were reexamined in 1997–1998 and 2007–2008. Mean age at the 15-year follow-up was 63 years. A confirmatory sample with 10 years follow-up was also included. MethodsScanners (1.5 Tesla) with surface coils were used at baseline and follow-up. Image analyzing software was used to measure distances and areas of interest of midsagittal and midaxial spine images. ResultsThe disc heights decreased at 5 years by 3.4% (0.4 mm) and 3.3% (0.4 mm) and at 15 years by 8.7% (1.0 mm) and 11.3% (1.3 mm) in the upper and lower discs, respectively (p<.001). Although not clear after 5 years, vertebra heights increased in mean by 3.1% (0.8 mm) in the upper lumbar levels and by 4.7% (1.1 mm) in the lower vertebrae after 15 years (p<.001). Vertebra height increases were associated with disc narrowing (p=.001). The mean annual shortening of the lumbar spine L1–S1 block was 0.13 mm/y, which was in line with the mean standing height that decreased little (174.7 cm at baseline and 174.4 cm at the follow-up). ConclusionsDiscs and vertebrae degenerate or remodel in concert: decreases in disc height appear to be compensated, in part, by accompanying increases in adjacent vertebra heights. The mechanism behind this novel finding and its implications require further study.

In-Accuracy Of Bone Density Measurements By DXA In Patients With Hemoglobinopathies and Iron Overload

IntroductionWhen monitoring bone health in patients with hemoglobinapathies, it is unknown if iron in surrounding tissues can lead to inaccuracies in the 2-dimensional assessment by Dual Energy X-ray Absorptiometry (DXA). ObjectiveThe aims of this study were: 1) to determine if the accuracy of lumbar spine assessment by DXA is affected by high liver iron concentration in patients with Sickle Cell Disease (SCD) or Thalassemia (Thal), 2) to test the effect of high tissue iron on vertebral Z-scores using phantoms, 3) to explore the ability to account for potential high-iron content effects when performing DXA examinations. MethodsThis study consisted of a retrospective chart review of data collected by the Children's Hospital & Research Center Oakland, Bone Density Clinic and Iron Measurement Program. Data from both DXA and Super Conducting Quantum Interference Device (SQUID) examinations collected between 2002 and 2013 from were abstracted. Only those patients with a diagnosis of SCD or Thal, who had a DXA and SQUID measurement within the same year were divided into an iron overload group (liver iron concentration (LIC) >3,000 µg Fe/g wet) and low iron (LIC <500 µg Fe/g wet) group. These patients were compared with healthy controls of which only 13 had both DXA and SQUID tests, 34 had DXA only. The 34 healthy controls without a SQUID test were included because it was assumed, based on their health screen that their liver-iron content would not interfere with DXA. In order to explore aim 1, a lumbar spine scan, by DXA, of each subject was re-analyzed to compare the derived areal bone mineral density (aBMD) Z-scores of lumbar vertebrae that are covered by the liver (presumed L1 or L1/L2) with the Z-scores of the lumbar vertebrae not covered by the liver (L3/L4). To explore aim 2, phantoms were designed to mimic the geometry of iron loaded tissues in order to explore the contribution of iron in specific tissues on the accuracy of DXA assessments. Phantoms were constructed using KNOX® brand gelatin and iron(II) sulfate heptahydrate and had concentrations ranging from 3,000 to 7,000 ug Fe/g gelatin. The iron-loaded phantoms were positioned obtusely overlying L1/L2 of the DXA daily quality control phantom to mimic the position of the liver. All data were analyzed by STATA ver.9.2 and were considered significant with a p<0.05. ResultsData from 102 total visits abstracted from 88 subjects [19 SCD (13 F), 24 Thal (12 F), age: 30.1 ± 11.9 years, mean ± SD], and 45 healthy controls (24 F, age: 25.4 ± 11.0 yrs) were analyzed. The SCD and Thal group had an average LIC by SQUID of 4651 ± 2079 µg Fe/g wet tissue and serum ferritin of 5408±2706 ng/mL; while the healthy controls, with both a DXA and a SQUID (n=17), had an average LIC of 251±144. Average aBMD Z-score of the lumbar spine L1-L4 in the Thal group was -2.0 ± 1.1 , the SCD was -2.0 ± 1.6 and the healthy controls: -0.3 ± 0.9. However, when individual vertebrae are analyzed separately, a significant difference was observed between the lumbar spine L1 BMD Z-scores compared to the combined means of L3/L4 Z-scores in the iron loaded population (Table 1). The discrepancy was even greater in subjects with LIC >5000 ug/g wet tissue. These findings were reproduced using heavily iron loaded phantoms.Table1Summary of Vertebrae Analysis by DXA in Controls, Patients and PhantomsSubject groupL1 aBMD Z-ScoreAvgL3/L4 aBMD Z-scoreMean difference L1 vs AvgL3/L4Difference (L1 vs AvgL3/L4)p-valueControls (n=52)-0.29 ± 0.16-0.50 ± 0.170.21 ± 0.08-0.42 ± 0.12<0.001SCD & Thal (n=50)-1.60 ± 0.18-2.21 ± 0.180.63 ± 0.09Controls (n=52)-0.29 ± 0.16-0.50 ± 0.170.21 ± 0.080.70 ± 0.16<0.001LIC >5000 (n=18)-1.43 ± 0.28-2.35 ± 0.260.91 ± 0.15Control Phantom (n=10)0.76 ± 0.08-0.17 ± 0.070.93 ± 0.03-1.0 ± 0.16< 0.001Iron Phantom (n=10)1.70 ± 0.47-0.22 ± 0.101.92 ± 0.15 ConclusionsInitial results for this study show that there is a relationship between liver iron content and lumbar spine aBMD Z-scores when evaluated by DXA. The BMD Z-score for L1 appears to be more significantly affected by the liver iron content then L2, which was unanticipated. When evaluating patients with liver iron content >3,000 ug/g wet tissue, it is important to consider the effects of iron contribution from the liver on the DXA spine scans and delete L1 and/or L2 from the total Z-score prior to making an interpretation. Failing to do so may under diagnose low bone mass in this at risk patient population. Disclosures:No relevant conflicts of interest to declare.

English

INTRODUCTION: Ancient schwannomas are rare encapsulated tumours that derive from the nerve sheath and should be removed due to their infrequent but existent possibility of malignancy. CASE PRESENTATION: We report a case of a mass located in the L4 lumbar spine in a 50 year old woman who presented with low back ache since 6 months. Ultrasound, CT and MRI were used to examine the characteristics of the lesion. Fine needle aspiration showed cytological characteristics of a benign schwannoma and final histological diagnosis was an Ancient schwannoma. A posterior approach, through a left paraspinal incision was used to approach the site of the mass. The lesion originated from a branch of the L4 nerve root of the L4-L5 lumbar spinal space and a complete excision was achieved, preserving the nerve. CONCLUSION: Paraspinal tumours can be benign to most aggressive lesions. It is therefore a necessity for the surgeon to understand the pathology preoperatively by a MRI and FNAC, to avoid overtreatment and major complications.

In Vivo Precision of the GE Lunar iDXA for the Assessment of Lumbar Spine, Total Hip, Femoral Neck, and Total Body Bone Mineral Density in Severely Obese Patients

No study has evaluated the precision of the GE Lunar iDXATM (GE Healthcare) in measuring bone mineral density (BMD) among severely obese patients. The purpose of the study was to evaluate the precision of the GE Lunar iDXATM for assessing BMD, including the lumbar spine L1–L4, L2–L4, the total hip, femoral neck, and total body in a severely obese population (body mass index [BMI]>40 kg/m2). Sixty-four severely obese participants with a mean age of 46 ± 11 yr, BMI of 49 ± 6 kg/m2, and a mean body mass of 136.8 ± 20.4 kg took part in this investigation. Two consecutive iDXA scans (with repositioning) of the total body (total body BMD [TBBMD]), lumbar spine (L1–L4 and L2–L4), total hip (total hip BMD [THBMD]), and femoral neck (femoral neck BMD [FNBMD]) were conducted for each participant. The coefficient of variation (CV), the root mean square (RMS) averages of standard deviations of repeated measurements, the corresponding 95% least significant change, and intraclass correlations (ICCs) were calculated. In addition, analysis of bias and coefficients of repeatability were calculated. The results showed a high level of precision for total body (TBBMD), lumbar spine (L1–L4), and total hip (THBMD) with values of RMS: 0.013, 0.014, and 0.011 g/cm2; CV: 0.97%, 1.05%, and 0.99%, respectively. Precision error for the femoral neck was 2.34% (RMS: 0.025 g/cm2) but still represented high reproducibility. ICCs in all dual-energy X-ray absorptiometry measurements were 0.99 with FNBMD having the lowest at 0.98. Coefficients of repeatability for THBMD, FNBMD, L1–L4, L2–L4, and TBBMD were 0.0312, 0.0688, 0.0383, 0.0493, and 0.0312 g/cm2, respectively. The Lunar iDXA demonstrated excellent precision for BMD measurements and is the first study to assess reproducibility of the GE Lunar iDXA with severely obese adults.

Drynaria fortunei-derived total flavonoid fraction and isolated compounds exert oestrogen-like protective effects in bone

Drynaria fortunei (Kunze) J. Sm. (DF), a Chinese herb commonly used for the treatment of bone fracture, was previously shown to exert anabolic effects on bone. However, its active ingredients as well as the mechanisms of action are far from clear. The present study aimed to characterise the bone anabolic effects of DF flavonoid fraction (DFTF) in ovariectomised (OVX) mice and to determine if DFTF and its isolated compounds exert oestrogen-like effects in rat osteoblast-like UMR-106 cells. Young OVX C57/BL6J mice were treated orally with DFTF (0·087, 0·173 or 0·346 mg/g per d), 17b-oestradiol (2 mg/g per d) or its vehicle for 6 weeks. Serum and urine samples were collected for biochemical marker analysis. Bones were collected for computed tomography analysis. UMR-106 cells were treated with DFTF and isolated compounds naringin, (2S)-5,7,30,50-tetrahydroxy-flavonone 7-O-neohesperidoside (compound 1) and 5,7-dihydroxychromone 7-O-neohesperidoside (compound 2). DFTF exerted dose-dependent effects in improving bone mineral densities as well as bone strength at the femur, tibia and lumbar spine L1 in OVX mice. DFTF and the three isolated compounds stimulated osteoblastic cell proliferation and alkaline phosphatase activities in a dose-dependent manner. In addition, they stimulated the ratio of osteoprotegrin and receptor-activator NF-kB ligand mRNA expression, suggesting their involvement in inhibiting osteoclastogenesis. These stimulatory effects on osteoblastic functions were abolished in the presence of oestrogen receptor (ER) antagonist, ICI 182780. The present results suggested that DFTF is effective in protecting against OVX-induced bone loss in mice, and its actions in regulating osteoblastic activities appear to be mediated by ER.

Biomechanical analysis of lumbar interbody fusion with an anisotropic hyperelastic model for annulus fibrosis

Based on computed tomography scanning images, this paper developed a detailed finite element model for the human L2–L4 lumbar spine segment with or without L3–L4 fusion. The model included vertebrae, intervertebral disc, facet articulating surfaces and various ligaments. A previously developed hyperelastic fibre-reinforced constitutive model was used to characterize the material property of annulus fibrosus. Numerical results of L3–L4 motion unit such as load–displacement curves and nucleus pressure were compared with experimental data to validate the FE model. The normal and fused lumbar spine segments under various loading conditions, such as flexion, extension and axial rotation, were analysed. The motion range and stress distribution of the L2–L4 models under different loading conditions were then obtained to investigate the effect of lumbar fusion operation. It was shown that under the same loading condition, the fused model had a much smaller body motion range. Interbody fusion brought out obviously different stress distribution in adjacent intervertebral disc annulus fibrosus. And it also increased the intradiscal pressure of adjacent intervertebral disc significantly.

Association Between Vascular Calcification and Osteoporosis in Men With Type 2 Diabetes

Atherosclerotic vascular disease is common in diabetes, and some data support a link with bone loss. This study evaluates the association between osteoporosis and clinical and metabolic factors and chronic complications of diabetes. We studied 59 diabetic men aged 50–80yr who were assessed with bone densitometry (dual-energy X-ray absorptiometry). Of them, 10.2% of the patients were found to have osteoporosis in the lumbar spine and 45.8% osteopenia, whereas in the femoral neck, 11.8% had osteoporosis and 49% had osteopenia. There was a significant association of osteoporosis in the lumbar spine L1–L4 (p=0.004) and in the femoral neck (p=0.036) with iliac artery calcification. In addition, there was no association with any other metabolic factors, clinical factors, or chronic complications of diabetes evaluated, except for an association between a previous personal history of fractures (p=0.016) and low bone mineral density in the femoral neck. In conclusion, we found a positive association between the iliac artery calcification and osteoporosis in type 2 diabetic male patients.

Association of bone mineral density (BMD), bone mineral content (BMC) and serum lipids in Hispanics with type 2 diabetes

O: To evaluate the association of bone mineral density, bone mineral content and serum lipids in Hispanics with diabetes.M: Baseline bone density and bone mineral measurements of 39 Hispanic subjects (mean age=53.9 ± 11.2, M=16, F=23) were obtained using the Fan Beam DXA Discovery A, software V 12.6. Serum lipid values were analyzed using the Beckman CX7 (Beckman Coulter, Fullerton, California) instrument and Beckman CX4CE instrument. Pearson's correlation was used to evaluate correlations between lipids and body composition values.R: There was a significant positive correlation between HDL and lumbar spine L1 BMC (r = 0.38, p=0.012), L2 BMC (r = 0.40, p=0.011), L4 BMC (r = 0.33, p=0.04), L2 BMD (r = 0.38, p=0.017), and L total BMD (r = 0.32, p=0.04). There was a significant negative association between serum triglycerides and lumbar spine L2 BMC (r = −0.378, p = 0.017).C: Bone mineral content and bone mineral density are significantly associated with selected lipid parameters.

The association of cognitive dysfunction and osteoporosis in old age

Little is known about the association between osteoporosis and cognitive dysfunction in the elderly. The aim of the study was to explore the correlation between the bone mineral density (BMD) and cognitive function in the elderly Korean. A population-based study was performed for a total of 720 elderly Korean, from the Ansan Geriatric Study (AGE study). Dual-energy x-ray absorptiometry (DXA) was performed on L1~L4 lumbar spine for evaluation of osteoporosis state. The cognitive function was evaluated by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery and the CERAD total score was tested. The distributions of CERAD total score were 57.86±13.40 in the elderly with osteoporosis, 62.72±12.39 in osteopenia, and 65.10±14.71 in normal (F=13.94, P<0.001). The distributin of MMSE score were 25.19±4.21 in the elderly with osteoporosis, 25.93±3.67 in osteopenia, and 26.34±4.21 in normal. The cognitive dysfunction was correlated with BMD (r=0.159, P<0.01). Osteoporosis was associated with cognitive dysfunction in the elderly. Additional studies are needed to confirm this correlation.

Answer to the Letter to the Editor of A.T. Turgut et al. concerning “Intradural extramedullary primary hydatid cyst of the spine in a child: a very rare presentation”

Respected Sir, Thanks for such an in-depth critical re-review of our article, we highly appreciate it. As a part of routine investigation USG abdomen was done and no cyst was found in any other part of the abdomen, and in primary MRI itself no cystic lesion was present in any other part of the body otherwise we must have mentioned it in our case report. In fact, as mentioned in our case report, in post-operative MRI (after 6 months) there was no cystic lesion present in any part of the body. Unfortunately the CT scan of the patient was not available. The details of MRI were provided by the radiologists and they mentioned it to be the cystic lesion extending from the L1 to L4 lumbar spine. The staining was done with the hematoxylin & eosin, and the ratio of magnification for figure 3 is ×400 and that for figure 4 is ×1,000. As for not inclusion of the names of radiologists and spinal surgeon, we wanted to say that we had tried to discuss the case from the pathologists point of view and wanted to give the message to radiologists and the surgeons that although the hydatid cyst is rare in spine, the possibility should always be kept in mind especially in endemic areas, which was also not thought of in this particular case, and the diagnosis of arachnoid cyst was made by the radiologist, and the surgeon operated the patient keeping in mind the arachnoid cyst, and it was only when the material submitted for histopathological examination that the diagnosis of hydatid cyst was made. Post operatively the patient received albedazole 800 mg daily in two divided doses for 6 months. The weakness of the lower limb at the first neurological examination at the admission to the hospital was Grade 3. We totally agree that long-term follow-up is mandatory in each case of central nervous hydatidosis before any conclusion can be drawn about the value of any therapeutic agent.

The reliability of paraspinal muscles composition measurements using routine spine MRI and their association with back function

This study examines the reliability of quantitative and qualitative muscle composition measurements of paraspinal muscle cross-sectional areas (CSAs) from routine lumbar spine magnetic resonance images and their association with maximal isokinetic lifting performance. The extent of paraspinal muscle composition reflects back function is currently not known. Measurements were repeated 4–8 weeks apart and different measurements of related constructs were compared. Participants were a population-based sample of 169 males, 35–67 years old, without considering the presence or absence of a history of low back pain or related problems in the selection of subjects. The quantitative and qualitative muscle composition measurements for axial magnetic resonance (MR) images of paraspinal muscles at the L3–L4 lumbar spine level, isokinetic lifting force and work, and body fat percentage were the main outcome measures. Results showed that the reproducibility of different paraspinal muscle composition measurements at the L3–L4 level was excellent for CSAs (ICC=0.95–0.99) and quantitative muscle composition measurements using cerebrospinal fluid adjusted signal intensity (ICC=0.96–0.99), and moderate for qualitative muscle composition ratings (Kappa=0.54–0.76). The correlations of the quantitative and qualitative muscle composition measurements with isokinetic lifting force and work were generally low ( r=0.02–0.41), and favoured the qualitative assessments. In conclusion, quantitative and qualitative muscle composition measurements of paraspinal muscles are highly reproducible tissue measures, have low associations with body fat and isokinetic lifting performance, and show that paraspinal muscle morphology using routine spine magnetic resonance imaging (MRI) is poorly related to back function.

Treatment of Osteopenia/Osteoporosis after Allogeneic Hematological Cell Transplantation with Zoledronic Acid.

Decreased bone mineral density (BMD) has been found to be a relatively common complication following haematopoietic cell transplantation (HCT). Only some studies exist about therapy with antiresorptive substances such as bisphosphonates. These studies analyse either short time therapy or only the use for female patients (pts). The aim of this study was to test the effect and tolerance of zoledronic acid in long time survival pts after HCT. Methods: 40 pts with osteoporosis (WHO T-score<=−2.5 SD) or osteopenia (T-score −1,0 to −2.5) were included in this prospective phase II study. The dose was 4 mg intravenously all 3 months for 2 years (yrs) in combination with calcium, vitamin D and hormone-replacement therapy. 36 patients were evaluated, who got at least 3 doses (24 male, 12 female; mean age 43,8 yrs). The diagnoses were AML (15pts), ALL (5pts), CML (11pts), NHL (3pts), MDS (2pts). 16 pts received peripheral stem cells, 16 bone marrow, 4 pts both (median 15,6 months since HCT). All pts were evaluated according biochemical routine parameters, deoxypyridinoline (Dpd) and calcium excretion in urine by longitudinal measurements. The BMD of lumbar spine L1–L4 (LS) and total femur hip (FH) was mostly determined by dual-energy X-ray absorptiometry (Lunar Prodigy). 26 pts had at least two measurements since base line beginning of the treatment. Results: We found a significant increase of BMD at LS and FH (Table 1). The increase was better in younger pts <45yrs than in older pts at FH: 8,9 vs 2,9 % at 1 yr and 12,0 vs 3,4% at 2 yrs (p=0,007 and p=0.02). Dpd decreased from 6,2 nmol/mmol creatinine to 3,6 after 1 yr (p=0.009) and 3,2 after 2 yrs (p=0.04). By subgroup evaluation no significant changes of BMD were observed by testing pts with (n=20) or without (n=6) corticosteroid therapy for GvHD before or during the study (n= 7 and n=19) and by testing pts with osteoporosis (n=13) vs osteopenia (n=13), sex differences, diagnoses or time to HCT. Zoledronic acid was well tolerated. 1 of the 40 pts was excluded after the fist dosis because of dramatically myalgia. 6 pts had mild flu-like syndromes, bone pain, chest pain or headache. Zoledronic acid increases BMD and reduces Dpd excretion significantly in patients with bone loss after allogeneic hematological cell transplantation.Table 1:baseline °1 yr°*2 yrs°*% 1 yr*% 2 yr*LS0.97+/−0.151.04+/−0.181.10+/−0.187.4+/−4,811.6+/−6.0FH0.82+/−0.100.87+/−0.110.91+/−0.105.6+/−5.37.5+/−7.0°g/cm² mean values (+/−SD) *p=0.000 vs baseline

Changes in the iliac crest–lumbar relationship from standing to prone

Background context It is known that positioning patients on the Jackson and Andrews operative tables causes changes in lumbar lordosis and pelvic rotation. However, it is unknown if the relationship between the iliac crest and underlying lumbar levels, in particular the L4–L5 interspace, changes from standing to prone on these tables. Purpose To assess the changes in the relationship between the iliac crests and lumbar spinal levels from standing to prone on two different operative positions using the Jackson and Andrews frames. Study design/setting Comparative analysis of iliac crest position relative to spinal levels in the preoperative standing position and while positioned on the Jackson and Andrews frames. Patient sample 48 randomly selected patients who underwent spinal surgery on either the Jackson or Andrews frame. Outcome measures Imaging. Method Comparative measurements were made of the preoperative and intraoperative plain lateral lumbar radiographs. The location of the superior border of the iliac crest relative to the L4 lumbar spine level was compared between radiographs. Results Preoperatively, the iliac crest aligned with L4/L4–L5 spinal level in 79.2% of the 48 patients compared with 85.5% of intraoperative cases (p=.59). Intraoperative iliac crest level aligned with the L4/L4–L5 level in 80.8% and 90.9% of the patients on the Andrews and Jackson tables respectively (p=.43). Thirty-four patients (70.8%) demonstrated no change in iliac crest alignment between intraoperative and preoperative radiographs. There was a trend for the iliac crest to shift cephalad with operative positioning. Conclusion Approximately 30% of patients demonstrated changes in the relationship between the iliac crest and lumbar levels between standing and positioning prone. The intraoperative position of the iliac crest aligned more accurately with the L4/L4–L5 spine level on the Jackson and Andrews frame compared with preoperative standing radiographs respectively. Further biomechanical studies should investigate the implication for lumbopelvic fixation.

Bone Mineral Density And Body Composition In Female Professional Ballet Dancers

Body composition has been suggested to be an important factor influencing reproductive function and bone formation in female athletes and dancers. PURPOSE To examine relationships between body composition and bone mineral density (BMD) in a number of skeletal sites. METHODS Twenty female professional ballet dancers (mean (± SD) age 26 ± 6 years; height 165.8 ± 4.9 cm; weight 50.6 ± 5.4 kg; and body mass index (BMI) 18.3 ± 1.1 kg.m−2) volunteered to participate in this study. Dual energy x-ray absorptiometry (DXA) was used to determine bone mineral density (BMD) at the following sites: dual neck of femur (FEMUR), dominant arm ultra distal radius (RADIUS) and L2–L4 lumbar spine (LUMBAR). A total body DXA scan was also used to determine total body bone mineral content, fat mass and lean tissue mass. BMD T-scores were calculated based young adult normative data for a white female UK population for interpretation based on recognised guidelines. RESULTS The mean (± SD) BMD for RADIUS, FEMUR and LUMBAR were 0.304 ± 0.042, 1.162 ± 0.122, 1.203 ± 0.130 g.cm−2 respectively. The mean young adult T-score for these sites was – 2.0 ± 1.2 (RADIUS), 0.1 ± 1.1 (FEMUR) and 1.5 ± 1.1 (LUMBAR) respectively. Fourteen of the participants (70%) had a T score ± −1.0 for the RADIUS and therefore would be diagnosed with osteopenia based on Word Health Organisation guidelines. Multiple regression analysis revealed that LUMBAR BMD was predicted by a five factor model of BMI, total body fat mass, bone mineral content, and lean tissue mass (r2 = 0.847, F(4, 19) = 20.69, P <0.0001) with the following equation y = 0.45 + 0.03(BMI) + −2.34E−5(fat mass) + 5.84E−4(bone mineral content) + −2.19E−5 (lean tissue mass). Regression analyses revealed no significant relationship between measures of body composition and RADIUS or FEMUR BMD. CONCLUSIONS The incidence of osteopenia in the ultra distal radius of female professional ballet dancers is high but could not be predicted by measures of body composition using regression analysis. Body composition measures may be predictive of lumbar spine BMD in this group.

P0259 BONE MINERAL STATUS IN CHILDREN AGED OVER 3 YEARS UNDERGOING LIVER TRANSPLANTATION

Introduction: Children with chronic liver disease are at risk of reduced bone mineral density (BMD) which may worsen in the months following liver transplantation (OLT). Probable aetiological factors include vitamin D (vit D) malabsorption, immobility and immunosuppressive drugs. Aim: To assess bone mineral health and vit D status in children over 3 years undergoing OLT. Methods: Children with cholestatic liver disease underwent dual energy X-ray absorptiometry (DXA) at the time of listing for OLT and bone mineral density was compared to normative values for children over 3 years. Volumetric bone density (BMAD) was calculated for the lumbar spine to adjust for body size. Bone ions, parathyroid hormone (PTH) and vit D metabolites were also measured. Results: 12 children (6 M; median age 9.4 yrs (3.0 to 14.6 yrs)) underwent assessment at a median of 1.5 months pre OLT. All were ambulant and only 1 previously had fractures. 10 were receiving vit D supplements and 7 supplemental feeding. Median height and weight z-scores were −0.7 (−4.8 to 3.0) and −0.2 (−3.3 to 1.8) respectively. Ionised calcium, phosphate and magnesium were low in 4, 7 and 3 children respectively but no child had a raised serum PTH. Although 9/10 and 5/10 had low 25-OH vit D2 and 25-OH vit D3 respectively, 1,25-(OH)2 vit D was normal in all cases. Median BMD z-score for L2 to L4 lumbar spine was −1.2 (−2.5 to 0.02) and for total body was −1.0 (−1.61 to −0.34). Median BMAD z-score was −0.7 (−3.0 to −1.3). Conclusion: In children aged over 3 undergoing OLT, bone mineral density, vitamin D and PTH status were better than anticipated. Optimal bone health can be achieved in children with chronic liver disease prior to OLT using vitamin D supplementation and ensuring optimal nutrition.

The Effect of Operative Position on Lumbar Lordosis

Study Design. The effect of intraoperative positioning on lumbar lordosis was retrospectively studied by radiographic analysis of 40 patients under general anesthesia. Objectives. The aim of this study was to document changes in segmental and total lumbar lordosis between preoperative standing and intraoperative radiographs taken in the “90-90” and prone positions. Summary of Background. Preservation of physiologic lordosis was an important consideration in reconstructive lumbar spine surgery. To avoid iatrogenic loss of lordosis when using spinal instrumentation and to facilitate decompressive procedures, it was necessary to understand how segmental alignments were affected by intraoperative positioning. Although many positioning techniques were used, the effect on lumbar lordosis was not well established. Methods. Preoperative (standing 36″ lateral spine) and intraoperative radiographs (lateral lumbar spine L1 to the sacrum) in either the “90-90” position on a Hastings frame (n = 20) or the prone position on a Jackson table (n = 20) were measured twice by two independent observers using Cobb methodology for total and segmental lordosis between L1 and S1. Data were analyzed for intra- and interobserver reliability and changes in segmental and total lordosis between standing and intraoperative radiographs. Results. Analysis of intra- and interobserver reliability revealed measurements were accurate and reproducible. The “90-90” position produced significant loss (P ≤ 0.01) of total and segmental lordosis at all levels except L1-L2, which showed no change. Segmental lordosis was reduced nearly 60% at L2-L3, L3-L4, and L4-L5, and total lordosis was reduced by more than 35%. The prone position on the Jackson table increased segmental lordosis at L5-S1 by 22% (P ≤ 0.01) and preserved total and segmental standing lordosis at all other levels. Conclusions. The “90-90” position on the Hastings frame was associated with significant reduction of total and segmental lordosis in the middle and lower lumbar spine. Positioning prone on a Jackson table maintained standing lumbar lordosis and increased lumbosacral lordosis.

Prevalence of vertebral fracture in women and the relationship with bone density and symptoms: the Chingford Study.

A population survey was performed to estimate the prevalence of vertebral fractures in women aged 45-69 and to determine their relationship to bone density and symptoms. Subjects were 1035 women aged 45-69 (mean 55.4 years, response rate 77%) from the age-sex register of a large 11,000-person general practice in Chingford, London. Thoracic and lumbar spine x-rays were read by a semiautomated quantitative method. Vertebral fractures were diagnosed using a variety of morphometric methods, including a new method we recently developed and the published methods of Melton and Eastell. These methods all detect abnormal ratios between anterior, central, or posterior vertebral height and between observed posterior vertebral height and values predicted from the posterior height of adjacent vertebrae. Bone mineral density (BMD) of lumbar spine L1-4 and neck of femur was measured by dual-energy x-ray absorptiometry (DXA). Using our method, 147, 14.2% (95% CI 12.0-16.2%) of the 1035 women, had minor fractures (at least two vertebral ratios 2-2.99 SD below the mean) and 20, 1.9% (95% CI 1.2-3.0%) of the total, had severe fractures (at least two ratios more than 3 SD below the mean). In the 147 women with minor fractures, bone density of the spine was not significantly lower than in the other 868 women, and reported back pain or loss of height was no more common. Women with multiple minor fractures did have lower bone density, by 0.4 SD. In the 20 women with severe fracture, bone density was significantly lower, by 0.6 SD.(ABSTRACT TRUNCATED AT 250 WORDS)