What is the role of CT-based Hounsfield unit assessment in the evaluation of bone mineral density in patients undergoing 1- or 2-level lumbar spinal fusion for degenerative spinal pathologies? A prospective study

BACKGROUND CONTEXT

Computed tomography-based vertebral attenuation values (CT-based HU) have been shown to correlate with T-scores on DEXA scan; and have been acknowledged as an independent factor for predicting fragility fractures. Most patients undergoing lumbar surgeries require CT as part of their preoperative evaluation.

PURPOSE

The current study was thus planned to evaluate the role of lumbar CT as an opportunistic investigation in determining BMD preoperatively in patients undergoing lumbar fusion.

STUDY DESIGN

Prospective cohort study.

PATIENT SAMPLE

Patients older than 45 years, who underwent one- to two-level lumbar (L3-S1 levels) fusions.

OUTCOME MEASURES

Comparison of the quantitative assessment of osteoporosis using Hounsfield Units (HU) on CT (L1-L5) and mean lumbar T-scores on DEXA (Dual Energy X-ray Absorptiometry).

HYPOTHESIS

HU on CT is comparable to T-score on DEXA as a suitable modality for the assessment of osteoporosis in patients undergoing one- to two-level lumbar fusion.

METHODS

A prospective cohort study was conducted between January and December 2021. Patients older than 45 years, who underwent one- to two-level lumbar (L3-S1 levels) fusions and had complete clinico-radiological records, were prospectively enrolled. A comparison was drawn between the HU (measured by placing an oval region of interest [ROI] over axial, sagittal and coronal images of lumbar vertebrae) on CT and T-scores on DEXA, and analyzed statistically. The HU values correlating best with normal (group A), osteopenia (B) and osteoporosis (C) categories (classified based on T-scores of lumbar spines) were determined statistically.

RESULTS

Overall, 87 patients (mean age of 60.56±11.63 years; 63 [72.4%] female patients) were prospectively studied. There was a statistically significant difference in the mean age (p=.01) and sex distribution (predominantly female patients; p=.03) of patients belonging to groups B (osteopenic) and C (osteoporotic patients), as compared with group A. The greatest correlation between T-score (on DEXA) and HU (on CT) for differentiating osteopenia (group B) from group A was observed at levels L1 (p<.001), L2 (p<.001) and L3 (p<.001). Based on receiver-operating characteristic (ROC) curve analysis, the cut-off values for HU for identifying osteopenia were 159 (at L1; sensitivity 81.6 and specificity 80) and 162 (at L2; sensitivity 80 and specificity 71.1). In addition, there was statistically significant correlation between T-score (on DEXA) and HU at all the lumbar levels for distinguishing osteoporosis (group C), although the difference was most evident at the upper lumbar (L1 and L2) levels (p<.001). Based on ROC analysis, cut-off HU values for defining osteoporosis were 127 (at L1; sensitivity 71.3 and specificity 70) and 117 (at L2; sensitivity 65.5 and specificity 90).

CONCLUSION

Based on our study, the measurement of HU on CT at upper lumbar levels can be considered as "surrogate marker" for BMD in the diagnosis of osteopenia (cut-off: 159 at L1, 162 at L2) and osteoporosis (cut-off: 127 at L1, 117 at L2) in patients undergoing lumbar fusion surgeries. The HU measurements on CT at the lower lumbar levels (L4 and L5) are less reliable in this preoperative scenario.

Which Bone Mineral Density Measure Offers a More Reliable Prediction of Mechanical Complications in Adult Spinal Deformity Surgery: Hounsfield Units or DEXA Scan?

OBJECTIVE

In patients undergoing adult spinal deformity (ASD) surgery, we sought to: (1) determine the relationship between dual-energy x-ray absorptiometry (DEXA)-measured bone mineral density (BMD), T-scores, and Hounsfield units (HU), and (2) compare the ability of DEXA-measured BMD, T-scores, and HU to predict mechanical complications and reoperations.

METHODS

A single-institution retrospective cohort study was undertaken for cases from 2013 to 2017.

INCLUSION CRITERIA

≥5-level-fusion, sagittal/coronal deformity, and 2-year follow-up. Multivariable regression controlled for age, body mass index, receiving anabolic medications, and postoperative sagittal vertical axis and pelvic-incidence lumbar-lordosis mismatch. A subanalysis was performed for osteopenic patients (-1 < T-score < -2).

RESULTS

Of 145 patients undergoing ASD surgery, 72 (49.6%) had both preoperative DEXA and computed tomography scans. Mean DEXA-measured BMD was 0.91 ± 0.52 g/cm2, mean T-score was -1.61 ± 1.03, and mean HU was 153.5 ± 52.8. While no correlation was found between DEXA-measured BMD and HU (r = 0.17, P = 0.144), T-score and HU had a weakly positive correlation (r = 0.31, P = 0.007). Mechanical complications occurred in 48 (66.7%) patients, including 27 (37.5%) proximal junctional kyphosis (PJK), 1 (1.4%) distal junctional kyphosis, 5 (6.9%) implant failure, 30 (41.7%) rod fracture/pseudarthrosis, 42 (58.3%) reoperations, and 16 (22.2%) reoperations due to PJK. No association was found between DEXA-measured BMD or T-scores with mechanical complications or reoperations. While univariate regression showed a significant association between lower HU and PJK (OR 0.98, 95%CI 0.97-0.99, P = 0.011), the significance was lost after multivariable analysis. When considering osteopenic patients (n = 37), only DEXA-measured BMD was an independent risk factor for PJK (OR 0.01, 95%CI 0.00-0.09, P = 0.017), with a threshold of 0.82 g/cm2 (AUC 0.70, 95%CI 0.53-0.84, P = 0.019).

CONCLUSIONS

Poor correlation was found between the 3 BMD modalities. DEXA-measured BMD may be superior to T-scores and HU in predicting PJK among patients with osteopenia with a threshold of BMD <0.82 g/cm2.

Intradepartmental orthopaedic fragility fracture liaison improves osteoporosis follow-up and treatment

OBJECTIVE

Over 2 million people in the United States sustain fractures related to osteoporosis annually, but only 20% of these patients receive treatment for their osteoporosis. The purpose of this study was to evaluate the effects of a fragility fracture liaison within the orthopedic department on treatment and follow up for osteoporosis.

DESIGN

Retrospective cohort study SETTING: University Level I Trauma center PARTICIPANTS: 112 patients treated under the aegis of an interdepartmental fracture liaison and 208 patients treated following the introduction of an orthopedic fragility fracture liaison at a single institution.

INTERVENTION

Transition from referral to interdepartmental fracture liaison to intradepartmental orthopedic fragility fracture liaison for fragility fractures.

MAIN OUTCOME MEASURES

Outcomes evaluated included demographics, fracture type, DEXA scan results, follow up and treatment plan, and subsequent fracture.

RESULTS

The mean age at time of fracture was 75 years, and the mean BMI was 27. The most common fracture types were femoral neck fractures (29%), pertrochanteric fractures (30%) and femur fractures (8%). There was a statistically significant increase in adherence to follow up and treatment after the introduction of an orthopaedic fragility fracture liaison.

CONCLUSIONS

The introduction of an intradepartmental fragility fracture liaison significantly increases osteoporosis follow-up and introduces the ability to combine both osteoporosis treatment and postoperative orthopaedic care. The results of this study highlight the utility of incorporating a fragility fracture liaison within the orthopaedic department given the economic burden of fragility fractures and the morbidity associated with these fractures.

LEVEL OF EVIDENCE

III cohort study.

Risk factors for osteoporosis among postmenopausal women in a Nigerian teaching hospital

Background

Osteoporosis is a progressive bone disease characterized by a reduction in bone mass and density, leading to bone fragility and an increased risk of sustaining fractures. Several studies have shown that the risk for osteoporosis increases with age and after menopause.

Methods

A cross-sectional study was undertaken of 422 postmenopausal women at the Family Medicine Clinic of the Lagos State University Teaching Hospital (LASUTH). Variables such as socio-demographic characteristics, anthropometric indices, and lifestyle habits of participants were assessed. In addition, bone mineral density was measured using a validated portable dual-energy X-ray absorptiometry scanner. The results of the bone mineral density were analyzed based on T-scores.

Results

The mean age of the study subjects was 59.8± ±6.4 years, while the mean age at menopause was 50.15 ± 4.1 years. The majority of the subjects were obese (41.5%), while the prevalence of osteoporosis and osteopenia was 15.1% and 30.6%, respectively. The use of oral steroids was associated with osteoporosis (P < 0.05).

Conclusion

We recommend regular bone mineral density screening of postmenopausal women at the primary care level for early diagnosis and treatment of osteoporosis to prevent fragility fractures.

The prevalence of Schmorl's nodes in osteoporotic vs normal patients: a Middle Eastern population study

The study was conducted to establish the association of Schmorl's nodes and osteoporosis in a Middle Eastern cohort. The prevalence of SN in this sample was 41.1%. It was most frequent in the lumbar spine typically solitary central lesions. Over 88% Schmorl's node cases were osteoporotic/osteopenic and only 11.6% normal.

INTRODUCTION

This study aims to identify the prevalence of Schmorl's nodes (SNs) in a cohort of Omani nationals, and also to determine any relation between osteoporosis and Schmorl's nodes.

METHODS

This retrospective observational study was conducted on Omani nationals. One thousand three hundred and forty-eight DEXA scan patients were included. Of these, 545 patients had complete X-rays and MRI scans that would help determine the SN status. The X-rays and sagittal, coronal, and axial T2-weighted MR images were used to identify the presence and exact location of the Schmorl nodes by one orthopedic trainee and confirmed by the senior author. The correlation of each parameter with the presence of SN was analyzed by the independent-samples T test and one-way ANOVA.

RESULTS

The overall prevalence of SN in this population sample appeared to be 41.1%. Over 88% of the SN-positive cases were either osteopenic or frankly osteoporotic by the WHO definition. Vast majority of SNs (87.1%) occurred in the lumbar spine and were central in location and mostly solitary. Statistical analysis of the data revealed significant correlation between osteopenia or osteoporosis and the presence of SNs.

CONCLUSIONS

The prevalence of SN in the sample of Omanis studied was 41.1% and was most frequently seen in older men in the lumbar spine. It is strongly associated with osteoporosis/osteopenia (88.4%) and frequently presents as solitary central lesions.

Lower Serum Irisin Levels Are Associated with Increased Osteoporosis and Oxidative Stress in Postmenopausal

Background

Irisin as an exercise-induced myokine was proposed to improve bone health. This study investigated the role of serum irisin (s-irisin) in patients with osteoporosis (OP) through correlating to most biological bone markers and oxidative stress.

Methods

A cross-sectional study recruited an eligible 175 postmenopausal women at Al-Hussien Teaching Hospital, Iraq. They were scanned by DEXA and stratified into two groups based on T-score; the first 95 patients as control group (GI) with -1 ≤ T-score and the second 80 patients as cases group (GII) with T-score ≤ -2.5. Demographic criteria were age, bone mineral density (BMD, g/cm2) and T-score. Serum irisin, total serum calcium (s-calcium), serum inorganic phosphate (s-phosphate), serum alkaline phosphatase (s-ALP), serum 25 [OH] vitamin D, the serum parathyroid hormone (s-PTH), serum Carboxy terminal collagen crosslinks (CTx), serum procollagen type I C-termidnal peptide (s-PICP), serum malondialdehyde (s-MDA) and serum superoxide dismutase (s-SOD) were collected from blood samples.

Results

Serum irisin were 31.84 ± 2.65 vs. 20.88 ± 2.71 ng/mL for control and trial groups, respectively. Lower levels of BMD, T-score, 25 [OH] vitamin D, and s-irisin along with a higher serum levels of PTH, CTx, PICP, MDA and SOD were observed in patients with osteoporosis. All parameters were statistically meaningful upon correlation (p< 0.0001), except age and s-calcium (p= 0.0088 and p= 0.187, respectively).

Conclusion

The results showed that, a significantly lower serum irisin levels among osteoporosis women, was intimately correlated to most bone turnover markers and it can be considered as encouraging results for clinical application in prediction and treatment of osteoporosis.

Type B insulin resistance syndrome associated with connective tissue disease and psoriasis

SUMMARY

Type B insulin resistance syndrome (TBIR) is characterised by the rapid onset of severe insulin resistance due to circulating anti-insulin receptor antibodies (AIRAs). Widespread acanthosis nigricans is normally seen, and co-occurrence with other autoimmune diseases is common. We report a 27-year-old Caucasian man with psoriasis and connective tissue disease who presented with unexplained rapid weight loss, severe acanthosis nigricans, and hyperglycaemia punctuated by fasting hypoglycaemia. Severe insulin resistance was confirmed by hyperinsulinaemic euglycaemic clamping, and immunoprecipitation assay demonstrated AIRAs, confirming TBIR. Treatment with corticosteroids, metformin and hydroxychloroquine allowed withdrawal of insulin therapy, with stabilisation of glycaemia and diminished signs of insulin resistance; however, morning fasting hypoglycaemic episodes persisted. Over three years of follow-up, metabolic control remained satisfactory on a regimen of metformin, hydroxychloroquine and methotrexate; however, psoriatic arthritis developed. This case illustrates TBIR as a rare but severe form of acquired insulin resistance and describes an effective multidisciplinary approach to treatment.

LEARNING POINTS

We describe an unusual case of type B insulin resistance syndrome (TBIR) in association with mixed connective tissue disease and psoriasis. Clinical evidence of severe insulin resistance was corroborated by euglycaemic hyperinsulinaemic clamp, and anti-insulin receptor autoantibodies were confirmed by immunoprecipitation assay. Treatment with metformin, hydroxychloroquine and methotrexate ameliorated extreme insulin resistance.

The complicated clinical course in a case of atypical lipodystrophy after development of neutralizing antibody to metreleptin: treatment with setmelanotide

SUMMARY

A patient with atypical partial lipodystrophy who had a transient initial response to metreleptin experienced acute worsening of her metabolic state when neutralizing antibodies against metreleptin appeared. Because her metabolic status continued to deteriorate, a therapeutic trial with melanocortin-4 receptor agonist setmelanotide, that is believed to function downstream from leptin receptor in the leptin signaling system, was undertaken in an effort to improve her metabolic status for the first time in a patient with lipodystrophy. To achieve this, a compassionate use (investigational new drug application; IND) was initiated (NCT03262610). Glucose control, body fat by dual-energy X-ray absorptiometry and MRI, and liver fat by proton density fat fraction were monitored. Daily hunger scores were assessed by patient filled questionnaires. Although there was a slight decrease in hunger scales and visceral fat, stimulating melanocortin-4 receptor by setmelanotide did not result in any other metabolic benefit such as improvement of hypertriglyceridemia or diabetes control as desired. Targeting melanocortin-4 receptor to regulate energy metabolism in this setting was not sufficient to obtain a significant metabolic benefit. However, complex features of our case make it difficult to generalize these observations to all cases of lipodystrophy. It is still possible that melanocortin-4 receptor agonistic action may offer some therapeutic benefits in leptin-deficient patients.

LEARNING POINTS

A patient with atypical lipodystrophy with an initial benefit with metreleptin therapy developed neutralizing antibodies to metreleptin (Nab-leptin), which led to substantial worsening in metabolic control. The neutralizing activity in her serum persisted for longer than 3 years. Whether the worsening in her metabolic state was truly caused by the development of Nab-leptin cannot be fully ascertained, but there was a temporal relationship. The experience noted in our patient at least raises the possibility for concern for substantial metabolic worsening upon emergence and persistence of Nab-leptin. Further studies of cases where Nab-leptin is detected and better assay systems to detect and characterize Nab-leptin are needed. The use of setmelanotide, a selective MC4R agonist targeting specific neurons downstream from the leptin receptor activation, was not effective in restoring metabolic control in this complex patient with presumed diminished leptin action due to Nab-leptin. Although stimulating the MC4R pathway was not sufficient to obtain a significant metabolic benefit in lowering triglycerides and helping with her insulin resistance as was noted with metreleptin earlier, there was a mild reduction in reported food intake and appetite. Complex features of our case make it difficult to generalize our observation to all leptin-deficient patients. It is possible that some leptin-deficient patients (especially those who need primarily control of food intake) may still theoretically benefit from MC4R agonistic action, and further studies in carefully selected patients may help to tease out the differential pathways of metabolic regulation by the complex network of leptin signaling system.

Misdiagnosis of Mullerian agenesis in a patient with 46, XX gonadal dysgenesis: a missed opportunity for prevention of osteoporosis

SUMMARY

Primary amenorrhea could be caused by disorders of four parts: disorders of the outflow tract, disorders of the ovary, disorders of the anterior pituitary, and disorders of hypothalamus. Delay in diagnosis and hormone substitution therapy causes secondary osteoporosis. Herein, we report a case of a 23-year-old phenotypical female who presented with primary amenorrhea from 46, XX gonadal dysgenesis but had been misdiagnosed as Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome or Mullerian agenesis. The coexistence of gonadal dysgenesis and MRKH was suspected after laboratory and imaging investigations. However, the vanishing uterus reappeared after 18 months of hormone replacement therapy. Therefore, hormone profiles and karyotype should be thoroughly investigated to distinguish MRKH syndrome from other disorders of sex development (DSD). Double diagnosis of DSD is extremely rare and periodic evaluation should be reassessed. This case highlights the presence of estrogen deficiency state, the uterus may remain invisible until adequate exposure to exogenous estrogen.

LEARNING POINTS

An early diagnosis of disorders of sex development (DSD) is extremely important in order to promptly begin treatment, provide emotional support to the patient and reduce the risks of associated complications. Hormone profiles and karyotype should be investigated in all cases of the presumptive diagnosis of Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome or Mullerian agenesis. The association between 46, XX gonadal dysgenesis and Mullerian agenesis has been occasionally reported as a co-incidental event; however, reassessment of the presence of uterus should be done again after administration of exogenous estrogen replacement for at least 6-12 months. A multidisciplinary approach is necessary for patients presenting with DSD to ensure appropriate treatments and follow-up across the lifespan of individuals with DSD.

Clinical challenges of a co-secreting TSH/GH pituitary adenoma

SUMMARY

Co-secreting thyrotropin/growth hormone (GH) pituitary adenomas are rare; their clinical presentation and long-term management are challenging. There is also a paucity of long-term data. Due to the cell of origin, these can behave as aggressive tumours. We report a case of a pituitary plurihormonal pit-1-derived macroadenoma, with overt clinical hyperthyroidism and minimal GH excess symptoms. The diagnosis was confirmed by pathology showing elevated thyroid and GH axes with failure of physiological GH suppression, elevated pituitary glycoprotein hormone alpha subunit (αGSU) and macroadenoma on imaging. Pre-operatively the patient was rendered euthyroid with carbimazole and underwent successful transphenoidal adenomectomy (TSA) with surgical cure. Histopathology displayed an elevated Ki-67 of 5.2%, necessitating long-term follow-up.

LEARNING POINTS

Thyrotropinomas are rare and likely under-diagnosed due to under-recognition of secondary hyperthyroidism. Thyrotropinomas and other plurihormonal pit-1-derived adenomas are more aggressive adenomas according to WHO guidelines. Co-secretion occurs in 30% of thyrotropinomas, requiring diligent investigation and long-term follow-up of complications.

Risk factors associated with osteoporosis in a cohort of prospectively diagnosed adult coeliac patients

BACKGROUND

Up to 75% of patients with untreated coeliac disease (CD) present with osteopenia or osteoporosis. Guidelines do not express with certainty whether each patient with newly diagnosed CD should undergo a dual-energy x-ray absorptiometry (DEXA) scan.

AIM

The aim of this article is to evaluate the prevalence of bone mineral density (BMD) alterations at diagnosis and risk factors associated with osteoporosis.

METHODS

A total of 214 adult patients (median age 38 years; female = 71.5%) newly diagnosed with CD underwent DEXA. The patients were divided into three groups: patients with normal BMD, those with osteopenia and those with osteoporosis. Clinical, histological and serological features were assessed and compared among the three groups. Logistic regression including relevant independent variables was performed.

RESULTS

DEXA indicated that 39.7%, 42.5% and 17.8% of the CD patients had normal BMD, osteopenia and osteoporosis, respectively. Logistic regression indicated that features significantly associated with osteoporosis were male gender (OR 4.7; 95%CI 1.1 to 20.8), age ≥45 years (OR 6.5; 95% CI 1.3 to 32.2), underweight (OR 7.4; 95% CI 1.3 to 42.5) and greater histological damage (Marsh 3C; OR 5.8; 95% CI 1.4 to 24.1).

CONCLUSIONS

BMD alterations were found in 60.3% of newly diagnosed adult coeliac patients. Osteoporosis was significantly associated with age ≥45 years, male gender, underweight and Marsh 3C, suggesting that at CD diagnosis, a DEXA scan might be beneficial, particularly in these subgroups of patients.

The computed tomography-based fractal analysis of trabecular bone structure may help in detecting decreased quality of bone before urgent spinal procedures

BACKGROUND CONTEXT

To date, no reliable method is available to determine the parameters of bone density based on the routine spinal computed tomography (CT) in the emergency setup. We propose the use of fractal analysis to detect patients with poor quality of bone before urgent or semi-urgent spinal procedures.

PURPOSE

This study aimed to validate the hypothesis that the CT-based fractal analysis of the trabecular bone structure may help in detecting patients with poor quality of bone before urgent spinal procedures.

STUDY DESIGN

This is a retrospective analysis of prospectively collected data.

METHODS

Patients in whom the dual-energy x-ray absorptiometry (DEXA) scan and lumbar spine CT were performed at an interval of no more than 3 months were randomly selected from a prospectively collected database. Diagnostic axial CT scans of L2, L3, and L4 vertebrae were processed to determine the fractal dimension (FD) of the trabecular structure of each spinal level. Box-count method and ImageJ 1.49 software were used. The FD was compared with the results of the DEXA scan: bone mineral density (BMD) and T-score by mean of correlation coefficients. Receiver operating characteristic curve analysis was later performed to determine the cutoff value of FD.

RESULTS

A total of 102 vertebral levels obtained from 35 patients (mean age 60±18 years; 29 female) were analyzed. The FD was significantly higher in the group of patients with decreased bone density (DBD) (T-score<-1.0) (1.67 vs. 1.43; p<.0001) and negatively correlated with BMD (R Spearman, -0.53; p<.0001) and T-score (-0.49; p<.0001). Receiver operating characteristic curve analysis revealed that a cutoff value of FD>1.53 indicates DBD (p<.0001; area under the ROC curve [AUC], 0.84; 95% confidence interval [CI], 0.76-0.91).

CONCLUSIONS

This study shows that fractal analysis of the lumbar spine CT images may be used to determine bone density before spinal instrumentation (eg, metastatic or traumatic cord compression). Further prospective studies comparing results of the fractal analysis of CT scans with quantitative CT (qCT) are warranted.

Lower Leg Length is Associated with Running Economy in High Level Caucasian Distance Runners

The aim of the present study was to investigate lower limb anthropometric and composition variables related to running economy (RE) and running performance in a homogeneous group of high level European distance runners. RE at the speeds of 14, 16 and 18 km·h⁻¹ (189 ± 12; 188 ± 11; 187 ± 11 O₂ ml·kg⁻¹·km⁻¹) and maximal oxygen uptake (VO_2max) (67.3 ± 2.9 ml·kg⁻¹·min⁻¹) of 13 high level distance runners were determined on a motorised treadmill. Anthropometric variables and body composition were measured. The BMI was related to RE at the speed of 14 (r² = 0.434; p = 0.014), 16 (r² = 0.436; p = 0.014) and 18 km·h⁻¹ (r² = 0.389; p = 0.023). Lower leg length was negatively related to RE at the speed of 16 and showed such a tendency at the speed of 14 and 18 km·h⁻¹. VO_2max indicated a moderate relationship with RE at the speeds of 14, 16 and 18 km·h⁻¹ (r² = 0.372, p = 0.030; r² = 0.350, p = 0.033; r² = 0.376, p = 0.026, respectively) which was confirmed by subsequent partial correlation analysis. While lower leg length and the BMI presented a relationship with RE, none of the calculated body composition and anthropometric proportions were related to RE or performance. The relationship between RE and VO_2max would confirm the notion that RE could be at least partly compensated by VO_2max to achieve high performance results.

Qualitative Evaluation of Digital Hand X-rays Is Not a Reliable Method to Assess Bone Mineral Density

BACKGROUND

The gold standard for evaluating bone mineral density is dual energy x-ray absorptiometry (DEXA). Prior studies have shown poor reliability using analog wrist X-rays in diagnosing osteoporosis. Our goal was to investigate if there was improved diagnostic value to visual assessment of digital hand X-rays in osteoporosis screening. We hypothesized that similar to analog counterparts, digital hand X-rays have poor correlation and reliability in determining bone mineral density (BMD) relative to DEXA.

METHODS

We prospectively evaluated female patients older than 65 years who presented to our hand clinic with digital hand and wrist X-rays as part of their evaluation over six months. Patients who had a fracture and were without DEXA scans within the past two years were excluded. Five fellowship-trained hand surgeons, blinded to DEXA T-scores, evaluated the x-rays over two assessments separated by four weeks and classified them as osteoporotic, osteopenic, or normal BMD. Accuracy relative to DEXA T-score, interobserver and intraobserver rates were calculated.

RESULTS

Thirty four patients met the inclusion criteria and a total of 340 x-rays reviews were performed. The assessments were correct in 169 cases (49%) as compared to the DEXA T-scores. A mean weighted kappa coefficient of agreement between observers was 0.29 (range 0.02-0.41) reflecting a fair agreement. The first and second assessment for all five physicians was 0.46 (range 0.19-0.78) reflecting a moderate agreement. Grouping osteoporosis and osteopenia together compared to normal, the accuracy, interobserver and intraobserver rates increased to 63%, 0.42 and 0.54 respectively.

CONCLUSION

Abnormally low BMD is a common occurrence in patients treated for upper extremity disorders. There is poor accuracy relative to DEXA scan and only fair agreement in diagnosing osteoporosis using visual assessments of digital x-rays.

[Osteoporosis detection using cone-beam computed tomography]

BACKGROUND

Osteoporosis is still underdiagnosed in Germany.

OBJECTIVES

Is it possible to detect osteoporosis on the basis of a cone-beam computed tomography image of the mandible and several measuring methods?

MATERIALS AND METHODS

Sixteen cone-beam computed tomography (CBCT) images from patients of the dental clinic at the University of Ulm were reinvestigated. When the CBCT images were processed the subjects were at least 55 years old, and the mandible was completely mapped on the image. Furthermore, a dual-energy X‑ray absorptiometry scan or a CT bone mineral density test was required for every subject. The subjects were divided into an osteoporosis group and a control group. The computed tomography mental index (CTMI), the computed tomography mandibular index superior (CTI[S]) and the computed tomography mandibular index inferior (CTI[I]) were deployed for comparison of the groups. In the first instance a comparison of the osteoporosis and control groups was made for both male and female subjects. Subsequently, only the images of the female subjects were compared to each other.

RESULTS

A possibility for osteoporosis can be expressed at CTMI values located < 3.0 mm. As well for CTI(S) < 0.18 and CTI(I) < 0.23. There arises a 66.7 % sensitivity and 70 % specificity for the mixed subject group and an 80 % sensitivity and 57.1 % specificity for the female subject group for CTMI and CTI(S). Furthermore, there are 50.0 % sensitivity and 70 % specificity for the mixed subject group and 60.0 % sensitivity and 57.1 % specificity for the female subject group for the CTI(I).

CONCLUSION

CTMI, CTI(S) and CTI(I) are only suitable for osteoporosis detection to a limited extent.

Diagnostic efficacy of Hounsfield units in spine CT for the assessment of real bone mineral density of degenerative spine: correlation study between T-scores determined by DEXA scan and Hounsfield units from CT

BACKGROUND

Dual-energy X-ray absorptiometry (DEXA) scan is an easy and cost-effective method of assessing bone mineral density (BMD). However, in patients with degenerative changes of the spine, overestimation of T-score on DEXA scan can occur despite low BMD during pedicle screw placement in spine surgery. The goal of this study is to assess BMD using Hounsfield unit (HU) measurements from computed tomography (CT) and to correlate these with DEXA-assessed T-scores in non-degenerative and degenerative patients.

METHODS

This study included 80 non-degenerative and 30 degenerative patients who underwent DEXA and spine CT assessment. The HU value on the mid-body axial images of CT and DEXA-assessed T-scores were measured from the L1-4 vertebrae.

RESULTS

In the non-degenerative group, HU values had a strong positive correlation with BMD and T-score, exhibiting correlation coefficients (r) greater than 0.7: the r-value (p value) between HU and T-score of the L1 vertebra was 0.701 (<0.001); 0.709 (<0.001) for L2; 0.709 (<0.001) for L3; 0.649 (<0.001) for L4; and 0.734 (<0.001) for L1-4. BMD assessed as +100 HU matched a T-score of -2.0 while +150, +200 HU matched T-scores of -1.0, 0.0. The differences were significant (p < 0.001). In the degenerative group, there was a weak positive correlation with r of approximately 0.4: the r-value (p value) was 0.300 (0.104); 0.457 (0.013); 0.433 (0.017); 0.447 (0.013) at each segment and 0.398 (0.031) for L1-4.

CONCLUSIONS

HU values provide a meaningful assessment of BMD and have a strong correlation with T-score. However, in degenerative patients, the T-score tended to be higher than the actual BMD. BMD assessment using HU might be helpful in predicting real BMD in patients undergoing instrumentation surgery with degenerative changes of the spine.

Assessment of bone health in breast cancer patients starting adjuvant aromatase inhibitors: A quality improvement clinical audit

Introduction

Adjuvant Aromatase Inhibitors (AIs) predispose breast cancer patients to accelerated bone loss. Guidelines recommend initial screening and follow up of bone mineral density with dual energy X-ray absorptiometry (DEXA) scan. In this audit we assessed the rate of adherence to these guidelines and introduced awareness measures to improve it.

Methods

All post-menopausal women who started upfront adjuvant AIs (letrozole in all patients) between January 2007 and December 2013 were retrospectively identified. The standard to be audited was “These patients should have a baseline DEXA scan requested within the first 3 months of starting adjuvant AIs therapy”. A 90% or more compliance was accepted as satisfactory. Corrective measures in the form of educational and awareness sessions followed by re-auditing of the practice over the subsequent 12 months were planned in case of lower compliance rate.

Results

Three hundred and sixty seven eligible patients were identified. Baseline DEXA scan was performed in 188 (51.2%) patients. As planned, this result triggered the conduction of 4 consecutive educational sessions over a period of 2 weeks. Re-auditing the practice in the pre-defined subsequent subjects showed compliance in 47/52 (90.4%) patients.

Conclusion

This study of a sizable cohort confirms previous observations that adherence to skeletal health guidelines in this patient population is less than adequate. Adherence is improved dramatically by raising the awareness of relevant physicians.

Bone Mineral Density in Sjögren Syndrome Patients with and Without Distal Renal Tubular Acidosis

Primary Sjögren's syndrome (pSS) can be complicated by distal renal tubular acidosis (dRTA), which may contribute to low bone mineral density (BMD). Our objective was to evaluate BMD in pSS patients with and without dRTA as compared with healthy controls. BMD of lumbar spine (LS) and femoral neck (FN) was measured in 54 pSS patients and 162 healthy age- and sex-matched controls by dual-energy X-ray absorptiometry (DXA). dRTA was defined as inability to reach urinary pH <5.3 after an ammonium chloride (NH4Cl) test. LS- and FN-BMD were significantly higher in pSS patients compared with controls (1.18 ± 0.21 g/cm(2) for patients vs. 1.10 ± 0.18 g/cm(2) for controls, P = 0.008 and 0.9 ± 0.16 g/cm(2) for patients vs. 0.85 ± 0.13 g/cm(2) for controls, P = 0.009, respectively). After adjustment for BMI and smoking, the LS- and FN-BMD remained significantly higher. Patients with dRTA (N = 15) did not have a significantly different LS- and FN-BMD compared with those without dRTA (N = 39) after adjustment for BMI, age, and gender. Thirty-seven (69 %) pSS patients were using hydroxychloroquine (HCQ). Unexpectedly, pSS patients had a significantly higher LS- and FN-BMD compared with healthy controls. Patients with dRTA had similar BMD compared with patients without dRTA. We postulate that an explanation for the higher BMD in pSS patients may be the frequent use of HCQ.

Body Fat Composition: A Predictive Factor for Sleep Related Breathing Disorder in Obese Children

INTRODUCTION

The association between body fat composition as measured by dual energy x-ray absorptiometry (DEXA) scanning and pediatric sleep related breathing disorder (SRBD) is not well established. We investigated the relationship between body mass index (BMI) and DEXA parameters and their association with SRBD in obese children.

PATIENTS AND METHODS

Overnight polysomnography was performed on obese/overweight children (10-17 years) with habitual snoring. Total body fat mass (g), trunk fat mass (g), total body % fat, and trunk % fat were determined by DEXA.

RESULTS

Forty-one subjects were studied. Logarithm (Log) total arousal index correlated with BMI (p < 0.01, r = 0.473), total body fat mass (p < 0.05, r = 0.331), and trunk fat mass (p < 0.05, r = 0.319). Log desaturation index correlated with BMI (p < 0.05, r = 0.313), total body fat mass (p < 0.05, r = 0.375), and trunk fat mass (p < 0.05, r = 0.391), whereas obstructive apnea hypopnea index (OAHI) did not. In males 10-12 years, there was a significant correlation between Log total arousal index and obesity parameters, but not for males aged 13-17 years. BMI correlated with DEXA parameters in all subjects: total body fat mass (p < 0.001, r = 0.850); total body % fat (p < 0.01, r = 0.425); trunk fat mass (p < 0.001, r = 0.792) and trunk % fat (p < 0.05, r = 0.318) and in 10-12 year old males. This relationship was not significant in males aged 13-17 years.

CONCLUSIONS

Total body fat mass and trunk fat mass as well as BMI correlated with total arousal index and desaturation index. BMI correlated with DEXA parameters in 10-12 year old males but not in 13-17 year old males. The value of using DEXA scanning to study the relationship between obesity and SRBD may depend on age and pubertal stage.

Adolescent pregnancy; a determinant of bone mineral density in peri-menopausal women?

OBJECTIVE

The present study aims to determine the effects of a history of adolescent pregnancy (AP) on the bone mineral density (BMD) of perimenopausal women.

METHODS

Overall, 240 women aged between 40 and 55 years, with a complaint of oligomenorrhea or amenorrhea not exceeding 1 year in duration, were evaluated. Evaluation included a DEXA scan and a detailed demographic survey for bone health. Comparison was made between women with a history of AP and those without.

RESULTS

In total, 87 women who had a history of AP were compared with 153 women who did not have a history of AP. The study groups did not differ significantly for most of the evaluated demographic factors. Women with a history of AP had higher gravidity and parity. Comparison of T-scores revealed lumbar BMD to be unaffected by AP (P=0.184), whereas femoral BMD was positively influenced by a history of AP (0.78±0.65 vs -1.06±0.67; P=0.042). In covariance regression models, after adjusting for parity and age of first menarche, AP still positively influenced femoral BMD. Without a history of AP, women were at increased risk for osteoporosis of femoral neck (odds ratio, 2.8, 95% CI 1.75-4.8).

CONCLUSIONS

The effects of AP on BMD are not well elucidated. Women with a history of AP had better femoral BMD scores, indicating a possible protective influence of AP on bone health.

BRIEF SUMMARY

Pregnancy during adolescence is associated with a better femoral bone mineral density than pregnancy at an older age. However, the effects did not extend to lumbar spine bone mineral density.

Prevalence and correlates of osteoporosis in chronic obstructive pulmonary disease patients in India

Background:

Chronic obstructive pulmonary disease (COPD) is a syndrome of progressive airflow limitation caused by the abnormal inflammatory reaction of the airway and lung parenchyma. Osteoporosis is one of the major extrapulmonary manifestations of COPD. The, prevalence of osteoporosis in COPD patients in Indian population is unknown.

Objectives:

To study the prevalence of osteoporosis in COPD and to define various risk factors associated with reduced bone mineral density (BMD) in COPD.

Materials and Methods:

The study was done in the department of Pulmonary Medicine of a tertiary care hospital. All the diagnosed cases of COPD according to the Global Initiative for Obstructive Lung Disease (GOLD) guidelines were included in this study. The present study was a prospective study in for a period of 1 year. A brief history of the patients was taken, especially regarding duration of illness, number of exacerbations in the past 3 years, smoking in pack years, and history of steroid use (both systemic and inhaled steroids) after which cumulative dose of steroids was calculated. Spirometry was done in all these patients to stage the severity of COPD according to GOLD criteria. DEXA scan of the lumbar spine was done using bone densitometer to determine osteoporosis. A world Health Organization (WHO) criterion for definition of osteoporosis was applied and patients with T-score of > –2.5 standard deviation (SD) were diagnosed to have osteoporosis, –1 SD to –2.5 SD were diagnosed to have osteopenia and < –1 SD as normal. Statistical analysis for association of COPD with osteoporosis was done using chi-square test. Risk factors for osteoporosis were identified by univariate and multivariate logistic regression analysis.

Results:

A total of 102 COPD patients were included in the study. Among these, 68 patients (66.6%) had osteoporosis and 20 patients (19.6%) had osteopenia. Majority (64.7%) of the patients who had osteoporosis had stage III and stage IV COPD disease. It was observed that as the severity grade of COPD increased, the risk of osteoporosis also increased. The bone mineral density (BMD) showed a significant difference among different stages of COPD. As the severity of the stage of COPD increased, BMD decreased. It was also observed that patients with lower body mass index (BMI) had higher prevalence of osteoporosis (37.3%) as compared to overweight patients. On univariate analysis, it was observed that risk factors for osteoporosis were female sex, higher number of exacerbations, BMI, and severity of COPD. After using multivariate logistic regression analysis, stage IV COPD (odds ratio (OR): 34.48, 95% confidence interval (CI): 1.59–1,000, P < 0.02), number of acute exacerbations >3 (OR: 30.3, 95% CI: 4.74–200, P < 0.01), and steroid cumulative dose >1,000 mg (OR: 7.35, 95% CI: 0.92–58.5, P < 0.04) were observed to be significant risk factors for osteoporosis in COPD patients.

Conclusions:

In the present study, the prevalence of osteoporosis was 66.6% and another 19.6% had osteopenia. As the severity of COPD increased, the risk of osteoporosis increased. GOLD stage III and stage IV patient had significantly lower BMD as compared to stage I and stage II of COPD disease. Stage IV COPD disease, use of oral or parenteral glucocorticoids, and repeated number of exacerbations were found to be independent risk factors for osteoporosis in COPD patients. Thus, high clinical suspicion and early diagnosis and treatment is required in the evaluation of osteoporosis in COPD patients so that the quality of life can be improved in these patients.