Women with vertebral fracture have less bone mass than those with Colles' fracture

Abstract

Background. Fractures are the most outstanding clinical complication of osteoporosis. Both vertebral and Colles' fractures are indistinctically associated to type I (postmenopausal) osteoporosis. It has not been clearly defined the possible differences, either in mineral metabolism regulation or in bone mass, between both type of fractures. Objective. To compare bone mass and biochemical bone remodeling markers in two groups of postmenopausal women, one composed by patients with vertebral fractures and another with patients with Colles' fracture. The results are compared to those obtained in a control group. Design. Descriptive, cross-sectional study. Patients. 408 Caucasian, Canarian, postmenopausal women. Group 1 was composed by 56 women who had suffered a Colles' fracture in the last two years. Group II was composed by 70 women with at least a vertebral fracture diagnosed by a lateral dorso-lumbar X-ray study. Control group composed by 282 healthy postmenopausal canary women, without fractures. Methods. Bone mineral density was determined in lumbar spine by Dual X-ray absorptiometry (DXA) and Quantitative Computed Tomography (TCC) and in proximal femur by DXA. The following biochemical bone remodeling markers (MBRO) were also determined: Alkaline Phosphatase (FAT), osteocalcin (GLA), rattrare-resistant acid phosphatase (FATR), 24 urine calcium and 24 hours urine hydroxyproline excretion; serum parathyroid hormone (PTH) and Calcitonin (CT) were also measured and a lateral dorso-lumbar X-ray study was also performed. Results. Patients with vertebral fractures have less height than other two groups. The weight mean of the whole women of the study shows the existence of overweight. Women with fractures, either vertebral o Colles' fractures have less bone mass than controls in the lumbar spine, by absolute figures (gr/cm2) or expressed as Tscore or Zscore. Following WHO densitometric criteria, in Colles' fracture patients, Tscore mean of bone mass measured at lumbar spine is osteopenic (-2.28), while this same mean in patients with vertebral fracture is osteoporotic (-2.75). 62.3% of patients with vertebral fractures have osteoporotic values by densitometry, while only 47.7% of Colles' fracture patients do so. Less than 15% of the fractured patients from both groups have normal values of bone mass, following WHO criteria. MBRO do not change. Conclusions. Women with vertebral fractures have less bone mass than those with Colles' fracture. The proportion of women with osteoporosis is higher in the women with vertebral fracture than in women with Colles' fracture.