Murphy Joshua S, Upasani Vidyadhar V, Yaszay Burt, Bastrom Tracey P, Bartley Carrie E, Samdani Amer, Lenke Lawrence G, Newton Peter O
Children's Orthopedics of Atlanta, Atlanta, GA.
Department of Orthopedics, Rady Children's Hospital, San Diego, CA.
Spine (Phila Pa 1976). 2017 Feb 15;42(4):E211-E218. doi: 10.1097/BRS.0000000000001761.
Retrospective review of prospectively collected data.
To determine whether the last substantially touched vertebra (LSTV) is a valid lowest instrumented vertebra (LIV) for both Lenke 1 and 2 curve patterns with AR lumbar modifiers, and to identify preoperative risk factors of distal adding-on.
Previous studies have recommended selecting the LSTV as the LIV for Lenke 1AR curves (main thoracic curve with A lumbar modifier and L4 tilt to the right (thoracic overhang/King type IV curve).
One-hundred sixty patients with a Lenke 1 or 2 curve pattern and AR lumbar modifier who underwent posterior spinal fusion between 2008 and 2012 were reviewed. All patients had minimum 2-year follow up. Patients were identified with distal adding-on between first erect radiographs and 2-year follow up based on previously defined parameters. Factors predictive of the adding-on phenomenon were identified in a multivariate binary logistic regression model.
Twenty-seven patients (17%) were identified as having distal adding-on of their primary thoracic curve; however, only 8 of 89 patients (9%) fused to the LSTV developed adding-on (P = 0.005). Three variables were found to be significant predictors of adding-on: LIV proximal to LSTV (odds ratio, OR 3.63; P = 0.01), Risser zero (OR 4.93; P = 0.02), and C7-CSVL distance <2 cm (OR 3.97; P = 0.01). The risk of adding-on increased as the number of predictors increased from 16% with one risk factor to 80% when all three preoperative risk factors were present (P < 0.001).
Choosing the LSTV as the LIV in Lenke 1 and 2 curve patterns with an AR lumbar modifier significantly decreases the risk of distal adding-on. Skeletally immature patients, those fused short of LSTV, and those with relative coronal balance preoperatively are at increased risk of distal adding-on between the initial postoperative visit and 2-year follow up.
对前瞻性收集的数据进行回顾性分析。
确定最后一个实质性触及椎体（LSTV）对于伴有AR腰椎修饰的Lenke 1型和2型脊柱侧凸是否为有效的最低固定椎体（LIV），并确定远端附加的术前危险因素。
既往研究推荐将LSTV选作Lenke 1AR型脊柱侧凸（主胸弯伴A腰椎修饰且L4向右侧倾斜（胸段悬垂/ King IV型曲线））的LIV。
回顾了2008年至2012年间接受后路脊柱融合术的160例Lenke 1或2型脊柱侧凸且伴有AR腰椎修饰的患者。所有患者均至少随访2年。根据先前定义的参数，在首次站立位X线片与2年随访之间确定出现远端附加的患者。在多因素二元逻辑回归模型中确定预测附加现象的因素。
27例患者（17%）被确定为其原发性胸弯出现远端附加；然而，在融合至LSTV的89例患者中，只有8例（9%）出现附加（P = 0.005）。发现三个变量是附加的显著预测因素：LIV位于LSTV近端（比值比，OR 3.63；P = 0.01）、Risser征为零（OR 4.93；P = 0.02）以及C7-CSVL距离<2 cm（OR 3.97；P = 0.01）。随着预测因素数量从1个危险因素时的16%增加到所有三个术前危险因素都存在时的80%，附加风险增加（P < 0.001）。
对于伴有AR腰椎修饰的Lenke 1型和2型脊柱侧凸模式，选择LSTV作为LIV可显著降低远端附加的风险。骨骼未成熟的患者、融合至LSTV以下的患者以及术前存在相对冠状面失衡的患者在术后首次随访至2年随访期间远端附加的风险增加。
4级。
