Densitometric patterns of spinal cord injury associated bone loss

Abstract

The purpose of the study was to use dual energy X-ray absorptiometry to measure bone mineral density (BMD) in the lumbar spine, the femoral neck, Ward's triangle, and the greater trochanter in 204 men (69 able-bodies controls and 135 spinal cord injured patients) strati®ed according to age (20 ± 39, 40 ± 59, and 60+ years old) in order to determine whether changes in BMD were age related, and to determine when these changes began to appear. The BMDs of the lumbar spine of both the 40 ± 59 year old and the 60+ year old patients were signi®cantly higher (P40.012) than the 40 ± 59 year old and 60+ year old controls, respectively. The femoral region BMDs of the 20 ± 39 year old and the 40 ± 59 year old patients were all signi®cantly lower (P40.027) than the 20 ± 39 year old and 40 ± 59 year old controls, respectively. When patients were grouped according to the time since their injury (0 ± 1, 1 ± 5, 6 ± 9, 10 ± 19, 20 ± 29, 30 ± 39, 40 ± 49, and 50 ± 59 years post injury) within the various age categories di erent results were obtained. In all the age categories, BMD loss occurred starting one year after spinal cord injury in the hip region. This bone loss took place gradually, reaching a signi®cant plateau (P40.017) at 19 years post injury and then started improving. The spine BMD in our patient population never signi®cantly decreased, and started improving as the age of the injury increased. Findings presented for the femoral regions were similar to other investigators' ®ndings; however, the steady bone mass maintained in the lumbar area, which increased with age regardless of the age of the injury, with the bone mass loss in the hip area, were the most notable new ®ndings.Keywords: spinal cord injury; spinal cord injury associated bone mass loss; bone mineral density (BMD); dual energy X-ray absorptometry (DEXA)

Intensive exercise may preserve bone mass of the upper limbs in spinal cord injured males but does not retard demineralisation of the lower body

“…Hip region BMD in our SCI group was 67, 66 and 63% that of the control group, for FN, WT and T, respectively. These ®gures are slightly lower than those found by BeDell et al 21 and Szollar et al, 36 but do support the extent of bone loss at these sites in our SCI individuals.…”

“…35,36 We found no in¯uence of DOI on any bone mass measurement. However our SCI group average for DOI was approximately 10 years, suggesting a plateau at a reduced BMD for the lower limbs and hip region, had been reached.…”

Osteoporosis after spinal cord injury

“…The patients older than 60 years had a nonsigni®cant increase in the BMD's of the spine and hip regions during this time. 17 We noticed no relation between age and sex of the patients and BMD loss. This may be related to the youth of our patients and the premenopausal status of our female patients.…”

“…13 Biering-Sorensen et al 16 showed that BMD of the femoral bone was continuously and signi®cantly decreased in SCI patients aged between 20 ± 55 compared to healthy individuals, while BMD of the lumbar spine was nearly unchanged. Szollar et al 17 showed that during the ®rst year of injury patients between the age of 20 ± 59 displayed a non signi®cant decrease in the BMD's of the spine and the hip regions. The patients older than 60 years had a nonsigni®cant increase in the BMD's of the spine and hip regions during this time.…”

The course of bone mineral density and biochemical markers of bone turnover in early postmenopausal spinal cord-lesioned females

“…Preservation of normal spine BMD in persons with SCL has been seen in many studies, [1][2][3][16][17][18][19] as opposed to findings in the general older female population and in patients with endocrine disorders, who do lose bone in the spine. 20 In individuals with SCL, however, secondary progressive skeletal abnormalities can lead to significantly increased vertebral bone densitometry results and thereby obscure an underlying osteoporosis.…”