Predictive factors for conversion from conservatively to surgically treatment osteoporotic thoracolumbar compression fractures based on sagittal parameters and magnetic resonance imaging features

PURPOSE

To investigate the relationship between sagittal plane characteristics of the spinal column and conservative treatment failure in acute osteoporotic spinal fractures (OSFs).

METHODS

As a retrospective study of single-institute data, thoracolumbar OSF patients with similar propensities in terms of location of fractures and results of bone mineral density were analyzed. Among them, 43 patients (group I) who needed reconstructive surgical interventions and 39 patients (group II) who obtained successful treatment through conservative care were included. General demographic data, radiographic features of fractures, and magnetic resonance imaging (MRI) features of fractures were analyzed. To investigate the relationship between global sagittal alignment of the spine and occurrence of delayed complication following OSFs, radiological sagittal parameters were analyzed.

RESULTS

The number of cases requiring reconstructive surgery was significantly higher when the index vertebra showed diffuse or mid-portion bone marrow changes in MRI. In terms of sagittal parameters, pelvic incidence (group I 59.1° ± 11.9°, group II 54.6° ± 9.8°) and thoracolumbar angle (group I 26.5° ± 14.1°, group II 17.4° ± 11.2°) were significantly higher in group I. Logistic regression analysis showed that higher pelvic incidence (OR 1.09, 95% CI 1.01-1.18, p value < 0.05) and higher thoracolumbar angle (OR 1.09, 95% CI 1.02-1.17, p value < 0.05) were significant risk factors for delayed complications requiring reconstructive surgery following OSFs.

CONCLUSION

Delayed complications requiring reconstructive surgery following OSFs are related to sagittal plane parameters of the spine such as high pelvic incidences, in addition to previously known radiographic characteristics of fractures.

Inter-observer agreement of vertebral fracture assessment with dual-energy x-ray absorptiometry equipment

PURPOSE

To investigate the time and effort needed to perform vertebral morphometry, as well as inter-observer agreement for identification of vertebral fractures on vertebral fracture assessment (VFA) images.

METHODS

Ninety-six images were retrospectively selected, and three radiographers independently performed semi-automatic 6-point morphometry. Fractures were identified and graded using the Genant classification. Time needed to annotate each image was recorded, and reader fatigue was assessed using a modified Simulator Sickness Questionnaire (SSQ). Inter-observer agreement was assessed per-patient and per-vertebra for detecting fractures of all grades (grades 1-3) and for grade 2 and 3 fractures using the kappa statistic. Variability in measured vertebral height was evaluated using the intraclass correlation coefficient (ICC).

RESULTS

Per-patient agreement was 0.59 for grades 1-3 fracture detection, and 0.65 for grades 2-3 only. Agreement for per-vertebra fracture classification was 0.92. Vertebral height measurements had an ICC of 0.96. Time needed to annotate VFA images ranged between 91 and 540 s, with a mean annotation time of 259 s. Mean SSQ scores were significantly lower at the start of a reading session (1.29; 95% CI: 0.81-1.77) compared to the end of a session (3.25; 95% CI: 2.60-3.90; p < 0.001).

CONCLUSION

Agreement for detection of patients with vertebral fractures was only moderate, and vertebral morphometry requires substantial time investment. This indicates that there is a potential benefit for automating VFA, both in improving inter-observer agreement and in decreasing reading time and burden on readers.

Asymptomatic vertebral fracture in Tunisian post-menopausal women at risk: prevalence and risk factors

Data are still scarce regarding the prevalence and the associated factors of vertebral fractures (VF) in the North Africa and the Middle East region. In this study, VF were common in at risk Tunisian women with a prevalence of 26.19%. Lower total hip T-score, having severe back pain, and being physically inactive were independently associated with VF.

INTRODUCTION

Vertebral fractures are related to a marked increase in morbidity and mortality and they are associated with a definite risk of subsequent fracture. Nevertheless, they remain underdiagnosed and little is known about their epidemiology in the African countries. In this first Tunisian study, we aimed to assess the prevalence and the associated factors of asymptomatic VF among at risk Tunisian post-menopausal women.

METHODS

In this cross-sectional study, we included post-menopausal women without a previous diagnosis of VF and who were referred for bone mineral density (BMD) measurement. Each participant had had an extensive medical history investigation, a BMD assessment, and a vertebral fracture assessment (VFA) scan using a dual energy X-ray absorptiometry. VF were defined using Genant semi-quantitative method.

RESULTS

Two hundred and ten post-menopausal women were included. The overall prevalence of VF was 26.19% and 9.52% of our participants had multiple VF. The prevalence of VF was significantly higher in older participants, those having a history of prior severe fragility fracture, or having at least one intrinsic fall. The percentage of low bone mineral density and osteoporosis were significantly higher in women with VF. After binary logistic regression analysis, severe back pain (OR = 3.016; 95% CI 1.304-6.974), regular physical activity (OR = 0.065; 95% CI 0.02-0.213), and total hip T-score (OR = 0.56; 95% CI 0.383-0.820) were independently associated with VF.

CONCLUSION

VF are very prevalent among at risk Tunisian post-menopausal women and their incorporation in a clinical and densitometric tool might identify more effectively subsequent fracture.

Vertebral fracture: epidemiology, impact and use of DXA vertebral fracture assessment in fracture liaison services

Vertebral fractures are independent risk factors for vertebral and nonvertebral fractures. Since vertebral fractures are often missed, the relatively new introduction of vertebral fracture assessment (VFA) for imaging of the lateral spine during DXA-measurement of the spine and hips may contribute to detect vertebral fractures. We advocate performing a VFA in all patients with a recent fracture visiting a fracture liaison service (FLS). Fracture liaison services (FLS) are important service models for delivering secondary fracture prevention for older adults presenting with a fragility fracture. While commonly age, clinical risk factors (including fracture site and number of prior fracture) and BMD play a crucial role in determining fracture risk and indications for treatment with antiosteoporosis medications, prevalent vertebral fractures usually remain undetected. However, vertebral fractures are important independent risk factors for future vertebral and nonvertebral fractures. A development of the DXA technology, vertebral fracture assessment (VFA), allows for assessment of the lateral spine during the regular DXA bone mineral density measurement of the lumbar spine and hips. Recent approaches to the stratification of antiosteoporosis medication type according to baseline fracture risk, and differences by age in the indication for treatment by prior fracture mean that additional information from VFA may influence initiation and type of treatment. Furthermore, knowledge of baseline vertebral fractures allows reliable definition of incident vertebral fracture events during treatment, which may modify the approach to therapy. In this manuscript, we will discuss the epidemiology and clinical significance of vertebral fractures, the different methods of detecting vertebral fractures, and the rationale for, and implications of, use of VFA routinely in FLS. • Vertebral fracture assessment is a tool available on modern DXA instruments and has proven ability to detect vertebral fractures, the majority of which occur without a fall and without the signs and symptoms of an acute fracture. • Most osteoporosis guidelines internationally suggest that treatment with antiosteoporosis medications should be considered for older individuals (e.g., 65 years +) with a recent low trauma fracture without the need for DXA. • Younger individuals postfracture may be risk-assessed on the basis of FRAX® probability including DXA and associated treatment thresholds. • Future fracture risk is markedly influenced by both site, number, severity, and recency of prior fracture; awareness of baseline vertebral fractures facilitates definition of true incident vertebral fracture events occurring during antiosteoporosis treatment. • Detection of previously clinically silent vertebral fractures, defining site of prior fracture, might alter treatment decisions in younger or older FLS patients, consistent with recent IOF-ESCEO guidance on baseline-risk-stratified therapy, and provides a reliable baseline from which to define new, potentially therapy-altering, vertebral fracture events.

Vertebral fracture assessment (VFA) in patients over 50 years of age with a non-severe peripheral fracture

The prevalence of unknown vertebral fractures evaluated by systematic vertebral fracture assessment (VFA) was 21% in patients over 50 years of age who suffered from a recent low-trauma non-severe peripheral fracture. The outcome of VFA resulted in changes in the management of osteoporosis.

INTRODUCTION

The aim of this study was to evaluate the utility of VFA in detecting vertebral fractures (VFs) in patients over 50 years of age, who suffered from a recent low-trauma non-severe peripheral fracture.

METHODS

This was an observational, single-center, cross-sectional study conducted in patients over 50 years of age, who presented a recent low-trauma non-severe peripheral fracture and were identified by the Fracture Liaison Service (FLS) of Amiens University Hospital between December 2017 and March 2019. VFA was interpreted by two trained rheumatologists providing a consensual reading using Genant semi-quantitative assessment.

RESULTS

Of the 359 eligible patients, 114 patients (31.8%) were included (mean age 65.6 ± 8.4 years; 89.5% female). Twenty-four patients (21%) had one or more VF diagnosed by VFA. The total number of VF diagnosed by VFA was 30: 20 VF (66.7%) grade 1, 7 VF (23.3%) grade 2, and 3 VF (10%) grade 3. Among the 24 patients with at least one prevalent VF diagnosed by VFA, 18 patients had an osteoporosis medication adaptation after the VFA results (16 osteoporosis medication initiation and 2 treatment intensification), and 6 patients would have had an osteoporosis medication even without the VFA results (66.7% versus 33.3% respectively, p < 0.001). Of the 51 patients receiving an osteoporosis medication after DXA and VFA, 18 patients (35.3%) had a change in the management of osteoporosis after knowing the outcome of VFA. All the VFs diagnosed by VFA were unknown before. We did not evidence any threshold (age, T-score, height loss) below which no VF was detected.

CONCLUSIONS

Our study demonstrates the usefulness of systematic VFA to detect prevalent VF in patients over 50 years of age who suffer from a recent non-severe peripheral fracture.

Accuracy of densitometric vertebral fracture assessment when performed by DXA technicians--a cross-sectional, multiobserver study

Six dual-energy X-ray absorptiometry (DXA) technicians reviewed lateral images of the spine for deformed vertebrae. The images were acquired with a DXA scanner in 235 patients referred for osteoporosis assessment. The outcome was compared to findings on spinal radiographs assessed by two radiologists. Three DXA technicians performed acceptable or better in identifying patients with fractured vertebrae.

INTRODUCTION

This is the first study to evaluate the accuracy of vertebral fracture assessment (VFA) when used by DXA technicians as a triage test to select patients with deformed vertebrae for spinal radiographs.

METHODS

Lateral single-energy scans and radiographs of the thoracolumbar spine (T4-L4) were acquired in 235 patients aged 65 years or more referred for osteoporosis assessment. Six DXA technicians evaluated lateral scans using dedicated software. The DXA technicians were trained to identify deformed vertebrae, but they did not assess the aetiology of deformity. Two radiologists evaluated the radiographs and their consensus evaluation served as the reference test for vertebral fracture. The main outcome was sensitivity and specificity of the DXA technicians' identification of patients with one or more grade II-III deformities according to Genant's classification.

RESULTS

The proportion of patients with one or more grade II-III vertebral fractures was 0.35. Sensitivity ranged from 0.61 to 0.83 and specificity ranged from 0.78 to 0.95 across the DXA technicians. In patients with grade II-III deformities on VFA, the mean probability of one or more grade II-III fractures was 0.74 (range 0.66-0.86). Conversely, in patients without such deformities, the mean probability of grade II-III fractures was 0.14 (range 0.10-0.18). Accuracy was lower for grade I-III deformities for all the DXA technicians.

CONCLUSION

Three of six DXA technicians achieved acceptable or better accuracy when using VFA to triage patients with grade II-III vertebral deformities for spinal radiographs. Heterogeneity between DXA technicians appears to be due to differences in subjective thresholds. VFA triage by DXA technicians to identify patients with grade II-III fractures is feasible.

Diagnosis of vertebral fractures using a low-dose biplanar imaging system

Vertebral fractures (VFs) are independent risk factors for new fractures. However, spine radiographs cannot be used as a screening method. EOS® has a good diagnostic value for the diagnosis of VF with a better legibility of upper thoracic spine and a higher concordance between readers compared to vertebral fracture assessment (VFA).

INTRODUCTION

Vertebral fractures (VFs) are risk factors for new fractures. However, spine radiographs cannot be used as a screening method for both cost and radiation concerns. EOS® X-ray imaging system which allows the acquisition of biplane images in an upright weight-bearing position with low radiation dose was used. The objective of this study was to compare EOS® to VFA for the diagnosis of VF.

METHODS

We conducted a cross-sectional study in subjects aged above 50 years with indication for spine imaging. EOS® and VFA of the spine were performed the same day. Sensitivity (Se), specificity (Sp), negative predictive value (NPV), and the interobserver precision of EOS® were compared to VFA for the diagnosis of VF.

RESULTS

Two hundred patients (mean age 66.2 years) were included. At the vertebral level, 2.4 and 3.6 % of vertebrae were not legible using EOS® and VFA, respectively (p = 0.0007). The legibility of spine was significantly affected by scoliosis (odds ratio (OR) = 2.8, p < 0.0001, for EOS®, and OR = 1.8, p = 0.0041, for VFA). Sixty-six patients (33.0 %) and 69 (34.5 %) had at least one VF using VFA and EOS®, respectively. At patient level, Se, Sp, and NPV for the diagnosis of VF of EOS® were 79.7, 91.6, and 99 %, respectively. Concordance between both observers was very good for EOS® (kappa-score = 0.89), higher than for VFA (κ = 0.67).

CONCLUSIONS

This study shows that EOS® has a good diagnostic value for the diagnosis of VF with a better legibility of upper thoracic spine and a higher concordance between readers compared to VFA.

Survey of French spine surgeons reveals significant variability in spine trauma practices in 2013

BACKGROUND

In France, attempts to define common ground during spine surgery meetings have revealed significant variability in clinical practices across different schools of surgery and the two specialities involved in spine surgery, namely, neurosurgery and orthopaedic surgery.

OBJECTIVES

To objectively characterise this variability by performing a survey based on a fictitious spine trauma case. Our working hypothesis was that significant variability existed in trauma practices and that this variability was related to a lack of strong scientific evidence in spine trauma care.

METHODS

We performed a cross-sectional survey based on a clinical vignette describing a 31-year-old male with an L1 burst fracture and neurologic symptoms (numbness). Surgeons received the vignette and a 14-item questionnaire on the management of this patient. For each question, surgeons had to choose among five possible answers. Differences in answers across surgeons were assessed using the Index of Qualitative Variability (IQV), in which 0 indicates no variability and 1 maximal variability. Surgeons also received a questionnaire about their demographics and surgical experience.

RESULTS

Of 405 invited spine surgeons, 200 responded to the survey. Five questions had an IQV greater than 0.9, seven an IQV between 0.5 and 0.9, and two an IQV lower than 0.5. Variability was greatest about the need for MRI (IQV=0.93), degree of urgency (IQV=0.93), need for fusion (IQV=0.92), need for post-operative bracing (IQV=0.91), and routine removal of instrumentation (IQV=0.94). Variability was lowest for questions about the need for surgery (IQV=0.42) and use of the posterior approach (IQV=0.36). Answers were influenced by surgeon specialty, age, experience level, and type of centre.

CONCLUSION

Clinical practice regarding spine trauma varies widely in France. Little published evidence is available on which to base recommendations that would diminish this variability.

Added value of trabecular bone score over bone mineral density for identification of vertebral fractures in patients with areal bone mineral density in the non-osteoporotic range

Detection of patients with vertebral fracture is similar for areal bone mineral density (aBMD) and trabecular bone score (TBS) in patients with non-vertebral fracture. In non-osteoporotic patients, TBS adds information to lumbar spine aBMD and is related to an index of spine deterioration.

INTRODUCTION

Vertebral fractures (VFs) are more predictive of future fracture than aBMD. The number and severity of VFs are related to microarchitecture deterioration. TBS has been shown to be related to microarchitecture. The study aimed at evaluating TBS in the prediction of the presence and severity of VFs.

METHODS

Patients were selected from a Fracture Liaison Service (FLS): aBMD and vertebral fracture assessment (VFA) were assessed after the fracture, using dual-energy X-ray-absorptiometry (DXA). VFs were classified using Genant's semiquantitative method and severity, using the spinal deformity index (SDI). TBS was obtained after analysis of DXA scans. Performance of TBS and aBMD was assessed using areas under the curves (AUCs).

RESULTS

A total of 362 patients (77.3% women; mean age 74.3 ± 11.7 years) were analysed. Prevalence of VFs was 36.7%, and 189 patients (52.2%) were osteoporotic. Performance of TBS was similar to lumbar spine (LS) aBMD and hip aBMD for the identification of patients with VFs. In the population with aBMD in the non-osteoporotic range (n = 173), AUC of TBS for the discrimination of VFs was higher than the AUC of LS aBMD (0.670 vs 0.541, p = 0.035) but not of hip aBMD; there was a negative correlation between TBS and SDI (r = -0.31; p < 0.0001).

CONCLUSION

Detection of patients with vertebral fracture is similar for aBMD and TBS in patients with non-vertebral fracture. In patients with aBMD in the non-osteoporotic range, TBS adds information to lumbar spine aBMD alone and is related to an index of spine deterioration.

Combined vertebral assessment and bone densitometry increases the prevalence and severity of osteoporosis in patients referred to DXA scanning

We performed a retrospective study to assess if vertebral fracture assessment (VFA) after routine bone mineral density (BMD) measurement on a dual-energy X-ray absorptiometry (DXA) machine had increased the number of patients diagnosed with osteoporosis and revealed previous unknown incident vertebral fractures. A total of 3275 patients were referred to bone densitometry by DXA to be screened for osteoporosis or evaluation of ongoing antiosteoporotic treatment. All spine X-rays obtained at our hospital from the same patients in the period from 3 mo before to 3 mo after the date of DXA scans were reviewed. Among the 3275 patients, 85% were females and 15% were males. In total, 68% of the patients had normal BMD, and 32% had osteoporosis. Vertebral fractures diagnosed by VFA were seen in 7.9% patients, of which 3.2% had normal BMD and 4.8% had osteoporosis assessed by BMD. The relative number of patients diagnosed with osteoporosis increased 9.79% and in absolute terms from 32.4% to 35.6% of patients referred to DXA. Addition of VFA to routine BMD measurement increased clinically significant the number of patients diagnosed with osteoporosis as well as the number of patients with fractures and thereby altered the severity and prognosis.

Validity and role of vertebral fracture assessment in detecting prevalent vertebral fracture in patients with rheumatoid arthritis

OBJECTIVES

We aimed to identify the validity and the role of vertebral fracture assessment (VFA) for the diagnosis of prevalent vertebral fracture (VF) in rheumatoid arthritis (RA) patients.

METHODS

Total of 100 women with RA who were 50 years or older were enrolled. All participants underwent lateral imaging of the thoraco-lumbar spine by radiography and VFA. All radiographs were analyzed by two radiologists. Discrepancies between radiologists for spine radiography were resolved by consensus and these results were defined as the reference standard. VFA interpretation was done independently by two nuclear medicine physicians. Fracture defined by VFA measure was done only when two physicians both independently reported fracture. The inter-rater agreement for the detection of VF on VFA was evaluated by kappa statistics. We calculated percent values for the diagnostic validity of VFA in detecting VF in the 100 women as a whole and according to the presence of previous fracture or back pain.

RESULTS

The prevalence of VF identified by spine radiography was 47%. Inter-rater agreement of VFA per vertebra by two VFA readers showed moderate agreement (kappa=0.60). The sensitivity, PPV, specificity and NPV of VFA compared to spine radiography were 57.3%, 30.9%, 89.1% and 96.1% for total vertebrae. All patients with history of previous VF (n=13) were visualized with VFA with 100% sensitivity but it has 64.7% sensitivity and 79.3% specificity in patients without previous VF (n=87).

CONCLUSION

VFA is most useful to identify patients without VF because of its high specificity and NPV in all spine level.

A review of the use of dual-energy X-ray absorptiometry (DXA) in rheumatology

The principal use of dual-energy X-ray absorptiometry (DXA) is to diagnose and monitor osteoporosis and therefore reduce fracture risk, associated morbidity, and mortality. In the field of rheumatology, DXA is an essential component of patient care because of both rheumatologists’ prescription of glucocorticoid treatment as well as the effects of rheumatological diseases on bone health. This review will summarize the use of DXA in the field of rheumatology, including the concern for glucocorticoid-induced osteoporosis, as well as the association of osteoporosis with a sampling of such rheumatologic conditions as rheumatoid arthritis (RA), systemic lupus erythematosus, ankylosing spondylitis, juvenile idiopathic arthritis, and scleroderma or systemic sclerosis. Medicare guidelines recognize the need to perform DXA studies in patients treated with glucocorticoids, and the World Health Organization FRAX tool uses data from DXA as well as the independent risk factors of RA and glucocorticoid use to predict fracture risk. However, patient access to DXA measurement in the US is in jeopardy as a result of reimbursement restrictions. DXA technology can simultaneously be used to discover vertebral fractures with vertebral fracture assessment and provide patients with a rapid, convenient, and low-radiation opportunity to clarify future fracture and comorbidity risks. An emerging use of DXA technology is the analysis of body composition of RA patients and thus the recognition of “rheumatoid cachexia,” in which patients are noted to have a worse prognosis even when the RA appears well controlled. Therefore, the use of DXA in rheumatology is an important tool for detecting osteoporosis, reducing fracture risk and unfavorable outcomes in rheumatological conditions. The widespread use of glucocorticoids and the underlying inflammatory conditions create a need for assessment with DXA. There are complications of conditions found in rheumatology that could be prevented with more widespread patient access to DXA.

Vertebral fracture assessment by new dual-energy X-ray absorptiometry

The aim of this study was to investigate the diagnostic performance of new dual-energy X-ray absorptiometry (DXA) technologies in the detection of vertebral fractures (VFs). Sixty-eight patients were submitted to DXA and conventional radiography (XR) on the same day. Lateral images of the spine were independently evaluated by three radiologists with different experience in skeletal imaging, in two sessions with 7 days between evaluations of the same anonymous images. The most expert physician repeated the analysis in a subsequent reading session after further 7 days. Results from expert XR evaluation were considered as gold standard. A semiquantitative approach was used to interpret images and morphometric analysis was performed when a VF was suspected. Seventy vertebrae (70/884, 7.9%) were excluded from the lesion-based analysis, as not evaluable: 11/70 (15.7%) missed by XR only, 56/70 (80.0%) missed by DXA only, 3/70 (4.3%) missed by both techniques (upper thoracic spine). Forty "true" fractures were detected (4.9% out of 814 vertebrae) in 26 patients (38.2% of the 68 studied patients). Twenty-five (62.5%) were mild fractures. DXA sensitivity and specificity were 70.0% and 98.3% on a lesion-based analysis, 73.1% and 90.5% on a patient-based analysis. Intra-observer agreement was excellent with no significant difference between the two techniques. Inter-observer agreement among the 3 observers was higher for XR (k=0.824 versus 0.720 in the detection of VFs, p=0.011). DXA accuracy was not influenced by radiologist experience; T4-L4 assessability as well as reproducibility and repeatability of the two techniques and accuracy of DXA were independent from sex, age, body mass index, grade of arthrosis. However DXA sensitivity was affected by mild VFs. Vertebral level did not affect the diagnostic performance with exception of vertebral body assessability. Latest improvements make VFs assessment by DXA competitive with traditional radiographic gold standard, providing consistent advantages and attractions. Few limitations still affect DXA performance and need to be overcome.