Vertebral Fractures: Which Radiological Criteria Are Better Associated With the Clinical Course of Osteoporosis?

Radiological diagnosis of prevalent osteoporotic vertebral fracture on radiographs: an interim consensus from a group of experts of the ESSR osteoporosis and metabolism subcommittee

When a low-energy trauma induces an acute vertebral fracture (VF) with clinical symptoms, a definitive diagnosis of osteoporotic vertebral fracture (OVF) can be made. Beyond that, a "gold" radiographic standard to distinguish osteoporotic from non-osteoporotic VFs does not exist. Fracture-shaped vertebral deformity (FSVD) is defined as a deformity radiographically indistinguishable from vertebral fracture according to the best of the reading radiologist's knowledge. FSVD is not uncommon among young populations with normal bone strength. FSVD among an older population is called osteoporotic-like vertebral fracture (OLVF) when the FSVD is likely to be associated with compromised bone strength. In more severe grade deformities or when a vertebra is collapsed, OVF diagnosis can be made with a relatively high degree of certainty by experienced readers. In "milder" cases, OVF is often diagnosed based on a high probability rather than an absolute diagnosis. After excluding known mimickers, singular vertebral wedging in older women is statistically most likely an OLVF. For older women, three non-adjacent minimal grade OLVF (< 20% height loss), one minimal grade OLVF and one mild OLVF (20-25% height loss), or one OLVF with ≥ 25% height loss, meet the diagnosis of osteoporosis. For older men, a single OLVF with < 40% height loss may be insufficient to suggest the subject is osteoporotic. Common OLVF differential diagnoses include X-ray projection artifacts and scoliosis, acquired and developmental short vertebrae, osteoarthritic wedging, oncological deformities, deformity due to high-energy trauma VF, lateral hyperosteogeny of a vertebral body, Cupid's bow, and expansive endplate, among others.

CT detects more osteoporotic endplate depressions than radiograph: a descriptive comparison of 76 vertebrae

This study analyzed elderly women who had chest radiograph and chest CT with indications other than spine disorders. Using CT images as reference, the study demonstrates that radiograph can miss a high portion of mild endplate depression. Detection of endplate depression is confounded by the limitation of projectional overlay for radiograph.

INTRODUCTION

The definition of radiographic OVF (osteoporotic vertebral fracture) remains controversial. Some authors suggest all OVFs should demonstrate endplate fracture/depression on radiograph. Using CT image as the reference, our study tests the hypothesis that a considerable portion of endplate depressions not seen on radiograph can be detected on CT.

METHODS

We retrospectively analyzed 46 female cases (age: 67-94 years) who had both chest radiography and chest CT with indications other than spine disorders. Sixty-six "vertebrae of interest" were identified on radiograph; then, CT images were read side-by-side with lateral chest radiograph.

RESULTS

Thirty-eight vertebrae (38/66) had anterior wedging deformity with height loss of < 20% while without radiographic endplate depression. Among them, 28 vertebrae had endplate depression and 8 vertebrae had no endplate depression on CT, while 2 vertebrae with "very" minimal deformity were read as normal on CT. In 9 vertebrae (9/66) with anterior wedging and height loss of ≥ 20%, all had additional endplate depression seen on CT. Five vertebrae (5/66) had ambiguous endplate depression on radiograph, 3 had endplate depression on CT while the other 2 vertebrae in one patient were false positive due to X-ray projection. There were 14 short height vertebrae (14/66) where middle and anterior heights were reduced to the same extent while did not show apparent anterior wedging or bi-concaving. Four cases each had one short height vertebra, and all had endplate depression on CT. Another 4 cases had 2, 2, 3, and 3 adjacent short height vertebrae, respectively, and all did not show endplate depression on CT. In addition, inspection of spine CT showed 10 vertebrae in 9 cases appeared normal on radiograph while demonstrated endplate depression on CT.

CONCLUSION

With CT images as reference, radiograph can miss a high portion of mild endplate depressions.

'Healthier Chinese spine': an update of osteoporotic fractures in men (MrOS) and in women (MsOS) Hong Kong spine radiograph studies

For the MrOS (Hong Kong) and MsOS (Hong Kong) baseline (BL) studies, community-dwelling 2,000 Chinese men (mean age: 72.3 years) and 2,000 Chinese women (mean age: 72.5 years) were recruited from 2001 to 2003. These two studies have spanned two decades till now. This review summarizes our spine radiograph results. Senile and post-menopausal osteoporosis were associated with intervertebral disc volume reduction; and in women, menopause accelerates disc degeneration. Elderly women's osteoporotic vertebral fracture (OVF) prevalence was double of that of elderly men. For year-4 follow-up (FU), male participants with BL OVF had little increased risk for further OVF. In our study comparing OVF rates in age-matched Hong Kong Chinese women and Italian Caucasian women (mean age: 74.1 years), endplate and/or cortex fracture (ECF) prevalence was 26% for Chinese and 47% for Italian. OVF with ≥40% vertebral height loss was recorded among 9.5% of the Chinese subjects while among 26% of the Italian subjects. OVFs in Italian subjects were more likely to be multiple and generally severer. Clinical spine fractures were recorded 133 cases/100,000 person-years in MrOS (Hong Kong) participants and 273 cases/100,000 person-years in MsOS (Hong Kong) participants. Literature review suggests the clinical vertebral fracture rates among elderly Hong Kong Chinese subjects are approximately half of those of American, Australian, and Canadian subjects. Data synthesis suggests elderly Caucasians have a higher degenerative spondylolisthesis prevalence, being approximately 70% higher than that of elderly Hong Kong Chinese. Literature review of other authors' publications shows, compared with Caucasians, Chinese have a much lower incident rate of back pain. We conclude that elderly Chinese have a generally healthier spine relative to elderly Caucasians.

Much lower prevalence and severity of radiographic osteoporotic vertebral fracture in elderly Hong Kong Chinese women than in age-matched Rome Caucasian women: a cross-sectional study

INTRODUCTION

Many earlier studies reported that East Asians and Caucasians have similar radiographic osteoporotic vertebral fracture (OVF) prevalence. Since elderly Chinese's osteoporotic hip fracture prevalence is half (or less than half) of that of their age-match Caucasians, we hypothesize that elderly Chinese's OVF prevalence could be only half, or even less than half, of that of their age-match Caucasians.

MATERIALS

Age-matched (mean: 74.1 years; range: 65-87 years) elderly women's radiographs (T4-L5) were from two OVF population-based epidemiological studies conducted in Hong Kong (n = 200) and in Rome (n = 200). All radiographs were double read by one reader in Hong Kong and one reader in Rome. Radiological osteoporotic vertebral deformity (ROVD) classification included no ROVD (grade 0), and ROVDs with < 20%, 20 ~ 25%, ≥ 25% ~ 1/3, ≥ 1/3 ~ 40%, ≥ 40% ~ 2/3, and ≥ 2/3 height loss (grade 1 ~ 6) as well as endplate/cortex fracture (ECF). Spinal deformity index (SDI) was calculated with each vertebra assigned a score of 0, 0.5, 1, 1.5, 2, 2.5, and 3 for no ROVD or ROVDs grade 1 ~ 6.

RESULTS

Seventy-seven (38.5%) Chinese subjects and 123 Italian subjects (61.5%) had ROVD respectively (p < 0.0001). Chinese subjects had ECF in 52 (26%) cases involving 100 vertebrae, while Italian subjects had ECF in 93 (47%) cases involving 230 vertebrae. ROVDs in Italian subjects tended to be more severe (total and mean SDI: 454.5 and 3.71 for Italian, and 212 and 2.72 for Chinese, p < 0.05), more likely to be multiple, more likely to have severe and collapsed grades. The slope of the relationship between age vs. SDI was steeper for the Italian subjects than for the Chinese subjects, suggesting ROVD severity developed faster for aging Italian subjects. A trend suggested earlier onset of ROVD among Italian.

CONCLUSION

OVFs in Chinese women tend to be less common, less severe, and less likely to have multiple fractures.

Improving osteoporotic vertebral deformity detection on chest frontal view radiograph by adjusted X-ray beam positioning

Purpose

In clinics, chest frontal view radiograph (CFR) is often taken for patients suspected of respiratory diseases and for assessing the heart and big vessels. CFR can be utilised to opportunistically detect osteoporotic vertebral fracture (OVF). However, for standard CFR, the site of highest OVF prevalence, i.e., the thoracolumbar junction, is usually 'off-centre' to the X-ray beam focus. This study tested the hypothesis that, if a CRF is taken with approximately two vertebrae lower than the standard X-ray beam positioning, the visualization of thoraco-lumbar junction can be much improved.

Materials

Four hospitals (A, B, C, D) provided 101 elderly women's digital CFRs with standard filming (28, 20, 24, and 21 cases respectively). Eighty four elderly female patients were prospectively recruited from hospitals-A and B, who were consecutive patients referred for chest radiograph with indications other than spine disorders. For theses prospective CFRs, the focus of X-ray beam was adjusted from towards vertebra T6 to towards T8, and standard lateral radiographs were obtained for reference. Visibility of spine and detectability of OVF were assessed on the CFRs. OVF was diagnosed based on chest lateral radiograph (CLR) after excluding other potential causes both radiographically and clinically.

Results

For standardly filmed CFR, spine readability was similar among those from Hospitals-A, B, and C, while performed less well for those from Hospital-D. With the prospective cases from Hospitals-A and B, spines readable to vertebra L1 level or lower increased from 48.2% for standard filming to 80.7% for adjusted filming. Spines with 'blurry' labelling decreased from 35.7% for standard filming to 15.7% for adjusted filming. For the 84 prospective cases, 42.9% (36/84) of the patients had OVF, and 26 cases of CLR positive cases were detected as having vertebral deformity on CFR. For minimal OVF cases (<20% height loss), 38% (5/13) were detected on CFR. Among 22 cases with apparent OVF (≥20% height loss), two cases were missed on CFR. False positivity was labelled in five cases, among them four cases had 'burry' spines.

Conclusion

CFR can help opportunistically detect OVF, which can be further improved if X-ray beam is adjusted to towards vertebra T8 instead of towards vertebra T6.

The translational potential of this article

This study confirms that CFR can help detect OVF opportunistically, and the visibility of the mid/lower thoracic spine and thoracolumbar junction can be much improved after minor adjustment of X-ray beam positioning. This study also suggests high positive rate of OVF in elderly Chinese female patients indicated for chest radiograph. Radiologists should be trained and sensitized in vertebral deformity identification on CFR as the clinical management can be improved by opportunistic detection of OVF.