Sarikaya Selda, Basaran Aynur, Tekin Yasin, Ozdolap Senay, Ortancil Ozgur
Department of Physical Medicine and Rehabilitation, Zonguldak Karaelmas University Faculty of Medicine, Zonguldak, Turkey.
J Clin Rheumatol. 2007 Feb;13(1):20-4. doi: 10.1097/01.rhu.0000255688.83037.42.
Osteoporosis at the lumbar spine and at the femur is a well-established complication in ankylosing spondylitis (AS), but the exact mechanism and the distribution of osteoporosis are not known absolutely.
To determine whether the osteoporosis is generalized or localized to central skeleton and to examine the relation between bone mineral density (BMD) and disease activity and radiologic progression in patients with AS.
In this study, 26 patients with AS and 33 healthy controls matched for age and sex were recruited to the study. Hip and forearm BMD were measured by dual energy X-ray absorptiometry (DEXA). Laboratory and clinical disease activity parameters were documented, and anteroposterior sacroiliac radiographs were taken to determine the radiologic progression.
The urine deoxypyridinoline levels of the patients with AS were statistically significantly higher (P = 0.02) and the serum osteocalcin levels were significantly lower with respect to controls (P = 0.03). The femoral neck and femur BMD values and T scores were significantly lower in patients with AS compared with the controls (P = 0.019, 0.003, 0.01, and 0.01, respectively). The differences in BMD values and T scores of the distal 1/3 radius between 2 groups were not statistically significant. The relation between BMD and disease activity, and radiologic progression in patients with AS could not detected.
Sparing of distal regions such as the as radius suggests that osteoporosis might be due to localized effects of inflammatory activity or immobility rather than a systemic effect. Both increased resorption and decreased formation might be involved in the pathogenesis of osteoporosis. Radius BMD may not be appropriate to evaluate bone loss in patients with AS.
腰椎和股骨骨质疏松是强直性脊柱炎（AS）中已被充分证实的并发症，但骨质疏松的确切机制及分布情况尚未完全明确。
确定AS患者的骨质疏松是全身性的还是局限于中轴骨骼，并研究骨密度（BMD）与疾病活动度及放射学进展之间的关系。
本研究纳入了26例AS患者及33例年龄和性别相匹配的健康对照者。采用双能X线吸收法（DEXA）测量髋部和前臂骨密度。记录实验室及临床疾病活动参数，并拍摄骶髂关节前后位X线片以确定放射学进展情况。
AS患者的尿脱氧吡啶啉水平显著高于对照组（P = 0.02），血清骨钙素水平则显著低于对照组（P = 0.03）。与对照组相比，AS患者的股骨颈和股骨骨密度值及T值显著降低（分别为P = 0.019、0.003、0.01和0.01）。两组间桡骨远端1/3的骨密度值及T值差异无统计学意义。未检测到AS患者的骨密度与疾病活动度及放射学进展之间的关系。
桡骨等远端部位未受累提示骨质疏松可能是炎症活动或制动的局部效应而非全身效应所致。骨吸收增加和骨形成减少可能均参与了骨质疏松的发病机制。桡骨骨密度可能不适用于评估AS患者的骨质流失情况。
