Bone and Cartilage Research Unit (BCRU), University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland,
J Bone Miner Metab. 2013 Sep;31(5):585-94. doi: 10.1007/s00774-013-0448-7. Epub 2013 Apr 4.
Bisphosphonates are widely used in the treatment of osteoporosis. It has been suggested that bisphosphonate treatment may be associated with atypical femoral fractures (AFFs), severely suppressed bone turnover rate, and decreased mineralization. We studied bone properties using bone quantitative histomorphometry and Fourier transform infrared spectroscopic imaging (FTIRI) on patients with AFFs. Further, the incidence of AFFs was estimated. Patient records of Kuopio University Hospital, Finland from January 2007 to June 2009 were reviewed to identify all patients who had sustained and had been operated for AFF (n = 8). The incidence of AFFs among patients on bisphosphonates was 0.61 fractures/1,000 patients per year, compared to 0.0067/1,000 per year among untreated patients. The patients that underwent bone biopsy (n = 4) were postmenopausal women (aged 55.5-81.1 years) who had been treated with bisphosphonates for over 4 years. Histomorphometry revealed low trabecular bone volume. Bone formation and resorption parameters tended to be low. Trabecular bone single labels were detected in one patient in the region of interest. In the extended label search, trabecular bone double labels were found in two patients. Based on FTIRI results, higher phosphate-to-amide I ratio and collagen maturity were found compared to normal samples. The heterogeneity of phosphate-to-amide I ratio was low. Overall incidence of atypical femoral fractures is low. The poor fracture resistance in some patients on long-term bisphosphonate-therapy could be explained by low bone formation, and changes in bone composition, i.e., higher degree of mineralization, increased collagen maturity, and decreased heterogeneity of the degree of mineralization.
双膦酸盐广泛用于骨质疏松症的治疗。有人认为，双膦酸盐治疗可能与非典型股骨骨折（AFF）、严重抑制骨转换率和矿物质化减少有关。我们使用骨定量组织形态计量学和傅里叶变换红外光谱成像（FTIRI）研究了 AFF 患者的骨特性。此外，还估计了 AFF 的发病率。回顾了芬兰库奥皮奥大学医院 2007 年 1 月至 2009 年 6 月的患者记录，以确定所有发生并接受 AFF 手术的患者（n=8）。接受双膦酸盐治疗的患者 AFF 发病率为 0.61/1000 名患者/年，而未接受治疗的患者为 0.0067/1000 名患者/年。接受骨活检的患者（n=4）为绝经后妇女（年龄 55.5-81.1 岁），接受双膦酸盐治疗超过 4 年。组织形态计量学显示低小梁骨体积。骨形成和吸收参数往往较低。在一个感兴趣区域的患者中检测到一个骨小梁单标记。在扩展标记搜索中，在两名患者中发现了骨小梁双标记。根据 FTIRI 结果，与正常样本相比，磷酸盐与酰胺 I 比和胶原成熟度更高。磷酸盐与酰胺 I 比的异质性较低。总体而言，AFF 的发病率较低。一些长期接受双膦酸盐治疗的患者骨折抵抗力差，可能是由于骨形成减少以及骨成分变化所致，即矿物质化程度增加、胶原成熟度增加和矿物质化程度异质性降低。
