Doherty Patrick, Welch Arthur, Tharpe Jason, Moore Camille, Ferry Chris
Neurosurgery, Lawrence + Memorial Hospital.
Division of Biostatistics and Bioinformatics, National Jewish Health.
Cureus. 2017 May 30;9(5):e1290. doi: 10.7759/cureus.1290.
Studies have shown that a significant learning curve may be associated with adopting minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) with bilateral pedicle screw fixation (BPSF). Accordingly, several hybrid TLIF techniques have been proposed as surrogates to the accepted BPSF technique, asserting that less/fewer fixation(s) or less disruptive fixation may decrease the learning curve while still maintaining the minimally disruptive benefits. TLIF with interspinous process fixation (ISPF) is one such surrogate procedure. However, despite perceived ease of adaptability given the favorable proximity of the spinous processes, no evidence exists demonstrating whether or not the technique may possess its own inherent learning curve. The purpose of this study was to determine whether an intraoperative learning curve for one- and two-level TLIF + ISPF may exist for a single lead surgeon.
Seventy-four consecutive patients who received one- or two-Level TLIF with rigid ISPF by a single lead surgeon were retrospectively reviewed. It was the first TLIF + ISPF case series for the lead surgeon. Intraoperative blood loss (EBL), hospitalization length-of-stay (LOS), fluoroscopy time, and postoperative complications were collected. EBL, LOS, and fluoroscopy time were modeled as a function of case number using multiple linear regression methods. A change point was included in each model to allow the trajectory of the outcomes to change during the duration of the case series. These change points were determined using profile likelihood methods. Models were fit using the maximum likelihood estimates for the change points. Age, sex, body mass index (BMI), and the number of treated levels were included as covariates.
EBL, LOS, and fluoroscopy time did not significantly differ by age, sex, or BMI (p ≥ 0.12). Only EBL differed significantly by the number of levels (p = 0.026). The case number was not a significant predictor of EBL, LOS, or fluoroscopy time (p ≥ 0.21). At the time of data collection (mean time from surgery: 13.3 months), six patients had undergone revision due to interbody migration. No ISPF device complications were observed.
Study outcomes support the ideal that TLIF + ISPF can be a readily adopted procedure without a significant intraoperative learning curve. However, the authors emphasize that further assessment of long-term healing outcomes is essential in fully characterizing both the efficacy and the indication learning curve for the TLIF + ISPF technique.
研究表明，采用双侧椎弓根螺钉固定（BPSF）的微创经椎间孔腰椎椎间融合术（MIS TLIF）可能存在显著的学习曲线。因此，有人提出了几种混合 TLIF 技术作为公认的 BPSF 技术的替代方法，声称减少固定或采用破坏性较小的固定方式可能会缩短学习曲线，同时仍能保持最小的破坏性益处。经棘突间固定（ISPF）的 TLIF 就是这样一种替代手术。然而，尽管考虑到棘突的有利位置，人们认为该技术易于适应，但尚无证据表明该技术是否有其自身固有的学习曲线。本研究的目的是确定单一主刀医生在进行单节段和双节段 TLIF + ISPF 时是否存在术中学习曲线。
回顾性分析了由单一主刀医生进行的 74 例连续接受单节段或双节段 TLIF 并采用刚性 ISPF 的患者。这是该主刀医生的首个 TLIF + ISPF 病例系列。收集术中失血量（EBL）、住院时间（LOS）、透视时间和术后并发症。使用多元线性回归方法将 EBL、LOS 和透视时间建模为病例数的函数。每个模型都包含一个变化点，以允许结果轨迹在病例系列期间发生变化。这些变化点使用轮廓似然法确定。使用变化点的最大似然估计值拟合模型。将年龄、性别、体重指数（BMI）和治疗节段数作为协变量纳入。
EBL、LOS 和透视时间在年龄、性别或 BMI 方面无显著差异（p≥0.12）。仅 EBL 在节段数方面有显著差异（p = 0.026）。病例数不是 EBL、LOS 或透视时间的显著预测因素（p≥0.21）。在数据收集时（距手术的平均时间：13.3 个月），6 例患者因椎间融合器移位接受了翻修手术。未观察到 ISPF 装置并发症。
研究结果支持 TLIF + ISPF 可以是一种易于采用的手术，且无显著术中学习曲线这一观点。然而，作者强调，对长期愈合结果进行进一步评估对于全面描述 TLIF + ISPF 技术的疗效和适应证学习曲线至关重要。
