Baylor College of Medicine and Houston VA Health Services Research & Development Center for Innovations in Quality, Effectiveness and Safety, Michael E. DeBakey Medical Center, Houston, Texas.
Nova Scotia Health Authority, Dalhousie University, Halifax, Nova Scotia, Canada.
Arthritis Rheumatol. 2018 Feb;70(2):212-221. doi: 10.1002/art.40325. Epub 2018 Jan 9.
Static alignment influences knee loading and predicts osteoarthritis (OA) progression. Periarticular bone is important in dispersing forces across the knee, and there is substantial evidence for molecular crosstalk between cartilage and subchondral bone. The aim of this study was to evaluate the relationship between periarticular trabecular bone morphology and bone mineral density (BMD) and knee alignment in OA.
This was a cross-sectional analysis of participants in the Osteoarthritis Initiative Bone Ancillary Study. Dual x-ray absorptiometry (DXA) was performed to measure tibial periarticular bone mineral density (paBMD). Magnetic resonance imaging of knee trabecular bone was performed to calculate the apparent bone volume fraction (aBVF), apparent trabecular number (aTbN), apparent trabecular spacing (aTbSp), and apparent trabecular thickness (aTbTh). Static alignment was assessed by measuring the hip-knee-ankle (HKA) angle on long-limb films.
The study group comprised 436 participants (mean ± SD age 65.4 ± 9.2 years, 46% female, mean ± SD body mass index 29.6 ± 4.6 kg/m ), 71% of whom had OA. Correlations between the HKA angle and medial:lateral paBMD, medial paBMD, aBVF, aTbN, aTbTh, and aTbSp were -0.63, -0.34, -0.29, -0.32, -0.22, and 0.30, respectively. More varus alignment was associated with higher medial:lateral paBMD, medial paBMD, aBVF, aTbN, aTbTh, and lower aTbSp. In OA knees, the results were more pronounced. In non-OA knees, the most consistent association was with medial:lateral paBMD.
Static alignment was associated with medial:lateral paBMD in all knees and with medial paBMD and trabecular morphometry in OA knees only. Aberrant knee loading may lead to increased relative subchondral bone density, which is partly related to a higher aBVF and a greater number of thicker trabeculae with smaller intertrabecular spacing. Knee DXA may be a useful early biomarker of knee OA.
静态对线会影响膝关节受力，进而预测骨关节炎（OA）的进展。关节周围骨在分散膝关节力方面很重要，并且有大量证据表明软骨和软骨下骨之间存在分子串扰。本研究旨在评估 OA 患者膝关节周围小梁骨形态和骨密度（BMD）与膝关节对线之间的关系。
这是一项对 Osteoarthritis Initiative Bone Ancillary Study 参与者的横断面分析。采用双能 X 线吸收法（DXA）测量胫骨关节周围骨矿物质密度（paBMD）。对膝关节小梁骨进行磁共振成像，计算表观骨体积分数（aBVF）、表观骨小梁数量（aTbN）、表观骨小梁间距（aTbSp）和表观骨小梁厚度（aTbTh）。通过测量长肢片上的髋膝踝（HKA）角来评估静态对线。
研究组包括 436 名参与者（平均年龄 65.4 ± 9.2 岁，46%为女性，平均体重指数 29.6 ± 4.6 kg/m ），其中 71%患有 OA。HKA 角与内侧：外侧 paBMD、内侧 paBMD、aBVF、aTbN、aTbTh 和 aTbSp 之间的相关性分别为-0.63、-0.34、-0.29、-0.32、-0.22 和 0.30。较大的内翻对线与较高的内侧：外侧 paBMD、内侧 paBMD、aBVF、aTbN、aTbTh 和较低的 aTbSp 相关。在 OA 膝关节中，结果更为明显。在非 OA 膝关节中，与内侧：外侧 paBMD 的相关性最一致。
在所有膝关节中，静态对线与内侧：外侧 paBMD 相关，而在 OA 膝关节中，仅与内侧 paBMD 和小梁形态相关。异常的膝关节受力可能导致相对软骨下骨密度增加，这部分与较高的 aBVF 和更大数量的更厚小梁以及更小的小梁间间距有关。膝关节 DXA 可能是膝关节 OA 的一种有用的早期生物标志物。
