Department of Orthopaedic Surgery, Rothman Institute, Thomas Jefferson University, Philadelphia, PA.
Spine (Phila Pa 1976). 2022 Dec 1;47(23):1620-1626. doi: 10.1097/BRS.0000000000004430. Epub 2022 Jul 15.
Retrospective cohort.
To determine if intraoperative on-table lumbar lordosis (LL) and segmental lordosis (SL) coincide with perioperative change in lordosis.
Improvements in sagittal alignment are believed to correlate with improvements in clinical outcomes. Thus, it is important to establish whether intraoperative radiographs predict postoperative improvements in LL or SL.
Electronic medical records were reviewed for patients ≥18 years old who underwent single-level and two-level anterior lumbar interbody fusion with posterior instrumentation between 2016 and 2020. LL, SL, and the lordosis distribution index were compared between preoperative, intraoperative, and postoperative radiographs using paired t tests. A linear regression determined the effect of subsidence on SL and LL.
A total of 118 patients met inclusion criteria. Of those, 75 patients had one-level fusions and 43 had a two-level fusion. LL significantly increased following on-table positioning [delta (Δ): 5.7°, P <0.001]. However, LL significantly decreased between the intraoperative to postoperative radiographs at two to six weeks (Δ: -3.4°, P =0.001), while no change was identified between the intraoperative and more than three-month postoperative radiographs (Δ: -1.6°, P =0.143). SL was found to significantly increase from the preoperative to intraoperative radiographs (Δ: 10.9°, P <0.001), but it subsequently decreased at the two to six weeks follow up (Δ: -2.7, P <0.001) and at the final follow up (Δ: -4.1, P <0.001). On linear regression, cage subsidence/allograft resorption was predictive of the Δ SL (β=0.55; 95% confidence interval: 0.16-0.94; P =0.006), but not LL (β=0.10; 95% confidence interval: -0.44 to 0.65; P =0.708).
Early postoperative radiographs may not accurately reflect the improvement in LL seen on intraoperative radiographic imaging, but they are predictive of long-term lumbar sagittal alignment. Each millimeter of cage subsidence or allograft resorption reduces SL by 0.55°, but subsidence does not significantly affect LL.
回顾性队列研究。
确定术中台上腰椎前凸（LL）和节段前凸（SL）是否与术后前凸变化一致。
矢状面排列的改善被认为与临床结果的改善相关。因此，确定术中影像学是否能预测术后 LL 或 SL 的改善非常重要。
对 2016 年至 2020 年间接受单节段和双节段前路腰椎体间融合术并联合后路器械固定的≥18 岁患者的电子病历进行了回顾性分析。使用配对 t 检验比较术前、术中、术后 X 线片上的 LL、SL 和前凸分布指数。线性回归确定沉降对 SL 和 LL 的影响。
共有 118 名患者符合纳入标准。其中，75 例为单节段融合，43 例为双节段融合。术中台上定位后 LL 明显增加[差值（Δ）：5.7°，P<0.001]。然而，术中至术后 2 至 6 周的 X 线片上 LL 明显减少（Δ：-3.4°，P=0.001），而术中至术后 3 个月以上的 X 线片上没有发现变化（Δ：-1.6°，P=0.143）。术前至术中 X 线片上 SL 发现明显增加（Δ：10.9°，P<0.001），但在 2 至 6 周的随访中（Δ：-2.7，P<0.001）和最终随访中（Δ：-4.1，P<0.001）减少。线性回归显示，椎间融合器沉降/移植物吸收能预测 SL 的变化（β=0.55；95%置信区间：0.16-0.94；P=0.006），但不能预测 LL 的变化（β=0.10；95%置信区间：-0.44 至 0.65；P=0.708）。
术后早期 X 线片可能无法准确反映术中影像学上看到的 LL 改善，但能预测长期腰椎矢状面排列。每毫米椎间融合器沉降或移植物吸收会使 SL 减少 0.55°，但沉降对 LL 没有显著影响。
4 级。
