Iweala Uchechi, Zhong Jack, Varlotta Caroline, Ber Roee, Fernandez Laviel, Balouch Eaman, Kim Yong, Protopsaltis Themistocles, Buckland Aaron J
Division of Spine, Department of Orthopedic Surgery, New York University Langone Health, New York City, NY.
Int J Spine Surg. 2021 Oct;15(5):953-961. doi: 10.14444/8125. Epub 2021 Oct 14.
There is controversy as to whether fusions should have the upper instrumented vertebrae (UIV) end in the upper lumbar spine or cross the thoracolumbar junction. This study compares outcomes and reoperation rates for thoracolumbar fusions to the sacrum or pelvis with UIV in the lower thoracic versus lumbar spine to determine if there is an increased reoperation rate depending on UIV selection.
A retrospective review of prospectively collected data was conducted from a single-center database on adult patients with degeneration and deformity who underwent primary and revision fusions with a caudal level of S1 or ilium between 2012 and 2018. Fusions were classified as anterior, posterior, or combination approach. Revision fusions included patients who had spinal surgery at another institution prior to their revision surgery at the center. Patients were categorized into 1 of 3 groups based on UIV: T9-T11, upper lumbar region (L1-L2), and lower lumbar region (L3-L5). Inclusion criteria were age 18 years or older and at least 1 year of clinical follow-up. Patients were excluded from analysis if they had tumors, infections, or less than 1 year of follow-up after the index procedure.
The reoperation rates for the UIV groups in the thoracic (28%) and upper lumbar (27%) spine were nearly equal in magnitude and were both significantly higher than the reoperation rate in the lower lumbar group (18%, = .046). Reoperation for the diagnosis of adjacent segment disease was 8.3% in the upper lumbar spine and statistically significantly higher than the reoperation rates for adjacent segment disease in the thoracic (1%) or lower lumbar (4.5%, = .042) spine. Reoperations for pseudoarthrosis and proximal junctional kyphosis were 13% and 4%, respectively, in the thoracic spine, both of which were statistically significantly different (pseudoarthrosis, = .035; proximal junctional kyphosis, = .002) from the reoperation rates for the same diagnoses in the upper lumbar spine (4.6% and 1%) or lower lumbar spine (6.2% and 0%). A multivariate logistical regression model at 2-year follow up did not show a statistically significant difference between reoperation rates between the thoracic and upper lumbar spine UIV groups.
Constructs with UIV in the thoracic spine suffer from higher rates of proximal junctional kyphosis and pseudoarthrosis, whereas those with UIV in the upper lumbar spine have higher rates of adjacent segment disease. Given this tradeoff, there is no certain recommendation on what UIV will result in a lower reoperation rate in thoracolumbar fusion constructs to the sacrum or pelvis. Surgeons must evaluate patient characteristics and risks to make the optimal decision.
关于融合术的上固定椎（UIV）应止于上腰椎还是跨越胸腰段交界处存在争议。本研究比较了下胸椎与腰椎的胸腰段至骶骨或骨盆融合术的疗效及再次手术率，以确定根据UIV的选择再次手术率是否会增加。
对一个单中心数据库中2012年至2018年接受初次和翻修融合术且尾端水平为S1或髂骨的成年退变和畸形患者的前瞻性收集数据进行回顾性分析。融合术分为前路、后路或联合入路。翻修融合术包括在该中心进行翻修手术前曾在其他机构接受脊柱手术的患者。根据UIV将患者分为3组中的1组：T9 - T11、上腰椎区域（L1 - L2）和下腰椎区域（L3 - L5）。纳入标准为年龄18岁及以上且至少有1年的临床随访。如果患者患有肿瘤、感染或在索引手术后随访时间少于1年，则排除在分析之外。
胸椎（28%）和上腰椎（27%）UIV组的再次手术率在数值上几乎相等，且均显著高于下腰椎组的再次手术率（18%，P = 0.046）。上腰椎因相邻节段疾病进行再次手术的比例为8.3%，在统计学上显著高于胸椎（1%）或下腰椎（4.5%，P = 0.042）因相邻节段疾病的再次手术率。胸椎因假关节形成和近端交界性后凸进行再次手术的比例分别为13%和4%，这两者与上腰椎（4.6%和1%）或下腰椎（6.2%和0%）相同诊断的再次手术率在统计学上均有显著差异（假关节形成，P = 0.035；近端交界性后凸，P = 0.002）。在2年随访时的多因素逻辑回归模型未显示胸椎和上腰椎UIV组之间的再次手术率有统计学上的显著差异。
胸椎UIV的固定结构近端交界性后凸和假关节形成的发生率较高，而上腰椎UIV的固定结构相邻节段疾病的发生率较高。鉴于这种权衡，对于胸腰段至骶骨或骨盆融合结构中何种UIV会导致较低的再次手术率，尚无明确建议。外科医生必须评估患者特征和风险以做出最佳决策。
