Impact of degenerative radiographic abnormalities and vertebral fractures on spinal bone density of women with osteoporosis

Abstract

CONTEXT: Measurements of bone density taken by dual-energy x-ray absorptiometry are the most accurate procedure for the diagnosis of osteoporosis. This procedure has the disadvantage of measuring the density of all mineral components, including osteophytes, vascular and extra vertebral calcifications. These alterations can influence bone density results and densitometry interpretation. OBJECTIVE: To correlate radiography and densitometry findings from women with osteoporosis, analyzing the influence of degenerative processes and vertebral fractures on the evaluation of bone density. DESIGN: Retrospective study. SETTING: Osteoporosis outpatients' clinic at Hospital das Clínicas, Universidade Estadual de Campinas. PARTICIPANTS: Ninety-six postmenopausal women presenting osteoporosis diagnosed by bone density. MAIN MEASUREMENTS: Bone mineral density of the lumbar spine and femoral neck were measured by the technique of dual-energy x-ray absorptiometry, using a LUNAR-DPX densitometer. Fractures, osteophytes and aortic calcifications were evaluated by simple x-rays of the thoracic and lumbar spine. RESULTS: The x-rays confirmed vertebral fractures in 41.6%, osteophytes in 33.3% and calcifications of the aorta in 30.2%. The prevalence of fractures and aortic calcifications increased with age. The mean bone mineral density was 0.783g/cm² and the mean T-score was --3.47 DP. Neither fractures nor aortic calcifications had significant influence on bone mineral density (P = 0.36 and P = 0.09, respectively), despite the fractured vertebrae having greater bone mineral density (P < 0.02). Patients with lumbar spine osteophytes showed greater bone mineral density (P = 0.04). Osteophytosis was associated with lumbar spine bone mineral density after adjustment for fractures and aortic calcifications by multiple regression (P = 0.01). CONCLUSION: Osteophytes and lumbar spine fractures can overestimate bone density interpretation. The interpretation of densitometry results should be carried out together with the interpretation of a simple lumbar spine x-ray in elderly women.

Degenerative changes at the lumbar spine—implications for bone mineral density measurement in elderly women

“…However, with increasing age, degenerative manifestations in the lumbar spine such as osteophytes and subchondral sclerosis become increasingly common. Such degenerative changes, and to a lesser extent clinically diagnosed or un-diagnosed vertebral compression fractures, scoliosis and aortic calcification, may result in artificially elevated spine BMD (4)(5)(6)(7)(8)(9)(10)(11)(12)(13). Hence the clinical use of spinal BMD measurements becomes increasingly problematic with age, and in fact difficulties in accurately assessing spinal BMD may already be apparent soon after menopause (14).…”

Variation in the PTH2R gene is associated with age-related degenerative changes in the lumbar spine

“…Furthermore, degenerative manifestations in the lumbar spine becomes increasingly common with advancing age and we have recently reported a gradient of vertebra being affected by these changes (L1 least and L4 most affected), with up to 36% of all L4 vertebrae having degenerative manifestations in elderly women [6]. Vertebral degenerative manifestations are a phenotype not commonly investigated in genetic studies of osteoporosis, yet in addition to the diagnostic implications of falsely elevated BMD readings [3,21], there is also the possibility that in genetic studies using elderly cohorts, potential associations with BMD may be masked.…”

“…The preferred measurement site for the diagnosis of spinal osteoporosis and prediction of vertebral fracture risk is the lumbar spine, however, it has long been observed that spinal DXA assessment is less reliable in the elderly as a result of degenerative manifestations including osteophytes, disc degeneration and subchondral sclerosis, vertebral compression fractures, degenerative scoliosis and aortic calcification [2,3].…”

Avaliação da cifose torácica em mulheres idosas portadoras de osteoporose por meio da biofotogrametria computadorizada

“…Osteoporosis is a common condition in one-third of white women over 65 years of age and after menopause, and its main complication is fractures of the vertebral body 4 , which intensify thoracic kyphosis 19 . Cortet 20 verified that postmenopausal, osteoporotic women with at least one fracture had a significant increase in thoracic kyphosis (63º) compared to the women without osteoporosis (52º), values similar to the ones observed in the present study.…”

“…In Brazil, it is estimated that osteoporosis affects approximately 35% of women over 45 years of age 4 . One of the criteria for an early osteoporosis detection proposed by the World Health Organization (WHO) is the measurement of the bone mineral density (BMD) by means of bone densitometry 5,6 , a method capable of measuring the amount of bone (mineral content) in a defined area or defined volumes in absolute values (g/cm²) 1 …”