Wagner Scott C, Formby Peter M, Helgeson Melvin D, Kang Daniel G
Department of Orthopedics, Walter Reed National Military Medical Center, Bethesda, MD.
Department of Orthopedic Surgery, Madigan Army Medical Center, Tacoma WA.
Spine (Phila Pa 1976). 2016 Nov 1;41(21):E1279-E1283. doi: 10.1097/BRS.0000000000001612.
Retrospective analysis.
The aim of the study was to report the incidence of undiagnosed osteoporosis in patients undergoing lumbar spine fusion using computed tomography (CT) Hounsfield units (HU).
We used a recent technique utilizing HU to estimate bone mineral density (BMD) of the lumbar spine and hypothesized that this technique would reveal a high percentage of undiagnosed osteoporotic patients undergoing transforaminal lumbar interbody fusion (TLIF).
We reviewed patients older than 50 years undergoing TLIF from a single-center and multiple surgeons. We determined the mean HU of L4 on axial CT. Average HU values for patients with diagnosed lumbar osteoporosis (DEXA BMD <0.75 g/cm) were compared to patients with osteopenia and normal BMD (between 0.75 and 0.9 g/cm and >0.9 g/cm, respectively). The percentage of patients with HU values consistent with osteoporosis, but without any formal evaluation, was also calculated.
Over 10 years, 143 patients older than 50 years underwent TLIF, and 128 had available perioperative lumbar CT scans. Men and Women comprised 60.2% and 39.8% of the population, respectively. Average age was 61.5 years (range: 50.0-83.5 years). Twenty-nine patients had both dual-energy X-ray absorptiometry and CT data available for analysis. There was a significant association with decreased HU in patients with lumbar BMD less than 0.75 g/cm (105.6 HU, 95% confidence interval [CI] 6.76) in comparison to patients with osteopenia (146.0 HU, 95% CI 4.09) and with normal BMD (165.9, 95% CI 21.35). Ten men (7.8%) and 15 women (11.7%) had HU values consistent with osteoporosis. Sixty-four percent of patients with osteoporotic HU values had never been formally evaluated for the disease.
HU may be an alternative to screening preoperative dual-energy X-ray absorptiometry scan and can minimize costs and resource utilization. We found a large proportion of patients older than 50 years undergoing TLIF had HU levels consistent with undiagnosed osteoporosis of the lumbar spine.
回顾性分析。
本研究旨在报告使用计算机断层扫描（CT）霍氏单位（HU）对接受腰椎融合术患者进行未诊断骨质疏松症的发病率。
我们采用了一种利用HU来估计腰椎骨密度（BMD）的最新技术，并假设该技术将揭示接受经椎间孔腰椎椎间融合术（TLIF）的未诊断骨质疏松症患者的高比例。
我们回顾了来自单中心和多位外科医生的年龄大于50岁接受TLIF的患者。我们在轴向CT上确定L4的平均HU。将诊断为腰椎骨质疏松症（双能X线吸收法BMD<0.75g/cm）患者的平均HU值与骨质减少和骨密度正常（分别在0.75至0.9g/cm和>0.9g/cm之间）的患者进行比较。还计算了HU值与骨质疏松症一致但未进行任何正式评估的患者百分比。
在10年期间，143名年龄大于50岁的患者接受了TLIF，其中128名患者有可用的围手术期腰椎CT扫描。男性和女性分别占该人群的60.2%和39.8%。平均年龄为61.5岁（范围：50.0 - 83.5岁）。29名患者同时有双能X线吸收法和CT数据可用于分析。与骨质减少（146.0HU，95%置信区间[CI]4.09）和骨密度正常（165.9，95%CI21.35）的患者相比，腰椎BMD小于0.75g/cm的患者HU降低存在显著相关性。10名男性（7.8%）和15名女性（11.7%）的HU值与骨质疏松症一致。HU值与骨质疏松症一致的患者中有64%从未接受过该疾病的正式评估。
HU可能是术前双能X线吸收法扫描筛查的替代方法，并且可以最小化成本和资源利用。我们发现很大比例年龄大于50岁接受TLIF的患者的HU水平与未诊断的腰椎骨质疏松症一致。
4级。
