Bone mineral density and bone turnover in spinal osteoarthrosis.

Abstract

Objectives-To determine whether there was a generalised increase in bone mineral density (BMD) in spinal osteoarthrosis (OA), and to determine the mechanism of this possible protection against osteoporosis as assessed by biochemical markers ofbone turnover. Methods-We studied 375 women (ages 50 to 85) from a population based group. Spinal OA was defined from radiographs as the presence of degenerative changes affecting intervertebral or facet joints. BMD of the lumbar spine (LS), femoral neck (FN) and total body (TB) was measured by dual energy x ray absorptiometry (Lunar DPX). Bone turnover rates were estimated from measurement of biochemical markers of bone formation and resorption (urine deoxypyridinoline (Dpyr) and serum bone specific alkaline phosphatase (BAP)). Results-BMD at each site was greater in the women with spinal OA (mean increase in LS-BMD 7 9%, 95%0 confidence interval (CI) 1-0 to 15-1; TB-BMD 8-4%, 95% CI 1P9 to 9 7; FN-BMD 6-4/o, 95% CI 0-3 to 12.6). (FN), although the increase at this site was smaller. Increased BMD in the presence of OA may, therefore, be greatest in the region affected by OA, but may also affect the skeleton generally.An increase in measured BMD in a region affected by OA may result from artefactual error caused by the presence of osteophytes, joint space narrowing and sclerosis within the region of interest. Alternatively, it may reflect a generalised effect of OA on the skeleton, or a combination of the two. If OA has a generalised effect on the skeleton, then study of bone metabolism in patients with OA may be important in understanding the pathophysiology of osteoporosis.Studies in patients with OA are complicated by the heterogeneous nature of the disease and by the poor correlation between symptoms and radiological signs.8 It is therefore necessary to determine the prevalence of OA from radiological surveys. It is also unknown whether all degenerative changes identified on radiographs are pathological, or whether minor changes may represent physiological changes of aging.There has been little study of the underlying mechanism of the interaction between bone mass and OA. The development of noninvasive biochemical assays for markers ofbone resorption and formation enable estimation of bone turnover in large cohorts of subjects. The urinary excretion of pyridinium crosslinks has been shown to be increased in patients with large joint OA,"'2 suggesting an increased rate of bone turnover in this condition; however, none of these studies allowed for the fact that there may have been an increased skeletal mass to account for the increase in crosslink excretion. There have been no reports of biochemical markers in subjects with spinal OA.It is now possible to make accurate and precise measurements of BMD using dual energy x ray absorptiometry (DXA). This technique enables measurement of the BMD of the whole skeleton, in addition to measurements at the IS and EN. It is also possible to make accurate measurements of the BMC of the whole skeleton which can be used to no...

Study of Peripheral Bone Mineral Density in Patients with Diffuse Idiopathic Skeletal Hyperostosis

“…The findings showed the global skeletal involvement in OA, being the changes present not only at the affected joints but also in other articular areas. More recent studies have confirmed these findings [20][21][22].…”

Osteoarthritis and bone mineral density: are strong bones bad for joints?

“…The hip and knee joints have been most studied, with several groups finding evidence of higher systemic BMD in those with OA at these joint sites in a variety of populations. [7][8][9][10][11] Higher BMD has also been reported in association with OA of the spine 10,12 and hand. 9,10,13 A limitation of cross-sectional studies is that the direction of causality cannot be formally assessed.…”

“…Cross-sectional investigations into the relationship between OA and bone turnover, which is generally inversely related to BMD owing to its role in bone loss, 33 have yielded conflicting findings. Levels of serum or urine bone turnover markers have been reported as both increased 34 and decreased 12,16 in individuals with radiographic OA of different joints compared with controls, with other studies reporting no association between bone turnover markers and radiographic OA severity. 35 Conversely, prospective studies suggest that higher rates of bone turnover may be related to more rapid OA progression.…”

Quantitative ultrasound measurements of the calcaneus in the prediction of lumbar spine degeneration

“…Ultrasound techniques are radiation-free, easy-tooperate, inexpensive and rapid, and they offer a reasonable alternative for the initial evaluation of elderly patients with osteoporosis [13]. Since several studies have reported finding a direct association between high BMD and osteoarthritis in the lumbar spine [7,15,16,27], we carried out this study to find out whether QUS might be useful in predicting the extent of degenerative changes in the lumbar spine of subjects experiencing pain. Our results showed a significant direct correlation between lumbar spinal stenosis and QUS parameters.…”