Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
J Clin Densitom. 2023 Oct-Dec;26(4):101433. doi: 10.1016/j.jocd.2023.101433. Epub 2023 Oct 8.
Trabecular bone score (TBS) is a bone mineral density (BMD)-independent risk factor for fracture. During DXA analysis and BMD reporting, it is standard practice to exclude lumbar vertebral levels affected by structural artifact. Although TBS is relatively insensitive to degenerative artifact, it is uncertain whether TBS is still useful in the presence extreme structural artifact that precludes reliable spine BMD measurement even after vertebral exclusions. Among individuals aged 40 years and older undergoing baseline DXA assessment from September 2012 to March 2018 we identified three mutually exclusive groups: spine BMD reporting performed without exclusions (Group 1, N=12,865), spine BMD reporting performed with vertebral exclusions (Group 2, N=4867), and spine BMD reporting not performed due to severe structural artifact (Group 3, N=1541). No significant TBS difference was seen for Group 2 versus Group 1 (referent), whereas TBS was significantly greater in Group 3 (+0.041 partially adjusted, +0.043 fully adjusted). When analyzed by the reason for vertebral exclusion, multilevel degenerative changes significantly increased TBS (+0.041 partially adjusted, +0.042 fully adjusted), while instrumentation significantly reduced TBS (-0.059 partially adjusted, -0.051 fully adjusted). Similar results were seen when analyses were restricted to those in Group 3 with a single reason for vertebral exclusions, and when follow up scans were also included. During mean follow-up of 2.5 years there were 802 (4.2 %) individuals with one or more incident fractures. L1-L4 TBS showed significant fracture risk stratification in all groups including Group 3 (P-interaction >0.4). In conclusion, lumbar spine TBS can be reliably measured in the majority of lumbar spine DXA scans, including those with artifact affecting up to two vertebral levels. However, TBS is significantly affected by the presence of extreme structural artifact in the lumbar spine, especially those with multilevel degenerative disc changes and/or instrumentation that precludes reliable BMD reporting.
骨小梁评分（TBS）是一种与骨密度（BMD）无关的骨折风险因素。在 DXA 分析和 BMD 报告中，标准做法是排除受结构性伪影影响的腰椎水平。虽然 TBS 对退行性伪影相对不敏感，但尚不确定 TBS 是否仍然有用，尤其是在存在严重结构性伪影的情况下，即使排除了椎体，也无法可靠地测量脊柱 BMD。在 2012 年 9 月至 2018 年 3 月期间接受基线 DXA 评估的 40 岁及以上个体中，我们确定了三个相互排斥的组：无椎体排除的脊柱 BMD 报告（第 1 组，N=12865）、有椎体排除的脊柱 BMD 报告（第 2 组，N=4867）和由于严重结构性伪影而未进行脊柱 BMD 报告的（第 3 组，N=1541）。第 2 组与第 1 组（参照组）相比，TBS 无显著差异，而第 3 组的 TBS 显著更高（部分调整后为+0.041，完全调整后为+0.043）。当按椎体排除的原因进行分析时，多节段退行性改变显著增加 TBS（部分调整后+0.041，完全调整后+0.042），而内固定显著降低 TBS（部分调整后-0.059，完全调整后-0.051）。当将分析仅限于第 3 组中具有单一椎体排除原因的个体，以及包括随访扫描时，也观察到类似的结果。在平均 2.5 年的随访期间，有 802 人（4.2%）发生了 1 次或多次骨折。在包括第 3 组在内的所有组中，L1-L4 TBS 均显示出显著的骨折风险分层（P 交互作用>0.4）。总之，大多数腰椎 DXA 扫描都可以可靠地测量腰椎 TBS，包括受影响达两个椎体水平的结构性伪影的扫描。然而，TBS 受腰椎严重结构性伪影的显著影响，尤其是那些存在多节段退行性椎间盘改变和/或内固定导致无法可靠报告 BMD 的情况。
