Fusini Federico, Pizones Javier, Moreno-Manzanaro Lucía, Sánchez Márquez José Miguel, Talavera Gloria, Fernández-Baíllo Nicomedes, Sánchez Pérez-Grueso Francisco Javier
Department of Orthopaedic and Traumatology, Orthopaedic and Trauma Centre, Città della Salute e della Scienza di Torino, University of Turin, Turin, Italy.
Spine Unit, Department of Orthopedic Surgery, Hospital Universitario La Paz, Madrid, Spain.
Int J Spine Surg. 2021 Jun;15(3):577-584. doi: 10.14444/8078. Epub 2021 May 7.
There are still no consensus criteria on how to select the lower instrumented vertebra (LIV) for traditional growing rods (TGRs) at index surgery. The aim was to evaluate whether the criteria used for adolescent idiopathic scoliosis fusion adapts to early onset scoliosis (EOS).
Retrospective analysis of prospectively longitudinal collected data in a consecutive cohort of patients with EOS treated with TGR, expanding from index surgery to 2 years after graduation. The LIV was analyzed regarding its relation to the stable vertebra (SV), substantially touched vertebra (STV), and not STV (NSTV). Failure of LIV selection was considered when revision surgery with distal extension was needed during follow up, due to adding on (ΔLIV tilt > 10°).
A total of 25 patients met inclusion criteria. Mean age was 8.6 ± 3 (at index surgery), 15.1 ± 1.8 (at graduation), and 17.8 ± 1.6 (at final follow up). The most frequent LIV at index surgery was L3 (13/25); in 13 cases, STV was selected as LIV; in 7, it was NSTV; and in 5, SV on the standard postero-anterior radiographs. During follow up, a significant increase in the mean LIV tilt ( = .049) and distal junctional angle ( = .017) was found. Nine of the 25 patients (36%) developed adding on: 20% (1/5) of those with LIV at SV, 38.5% (5/13) at STV, and 42.8% (3/7) at NSTV. Of those 9 cases of adding on, only four needed distal extension (mean LIV tilt = 17.6°): 2 STV patients (15.4%), and 2 NSTV patients (28.6%). None of the patients with the LIV chosen at SV needed distal extension due to adding on.
The more cranial the selection of the LIV above the SV, the higher the risk of adding on and of revision surgery with distal extension during follow up. Saving motion segments could be justified by choosing STV as LIV because the need for distal extension is not high, and it can be scheduled during lengthening procedures or at graduation surgery.
Choosing the correct LIV in TGR index surgery is crucial to have a secure distal foundation, control and correct the deformity during growth, and save distal segments to allow growth and mobility.
在初次手术时，对于传统生长棒（TGR）如何选择下固定椎（LIV）尚无共识标准。本研究旨在评估青少年特发性脊柱侧凸融合术所采用的标准是否适用于早发性脊柱侧凸（EOS）。
对前瞻性纵向收集的连续队列中接受TGR治疗的EOS患者的数据进行回顾性分析，范围从初次手术至毕业2年后。分析LIV与稳定椎（SV）、显著触碰椎（STV）和非显著触碰椎（NSTV）的关系。当随访期间因附加（ΔLIV倾斜>10°）而需要进行远端延长的翻修手术时，则认为LIV选择失败。
共有25例患者符合纳入标准。平均年龄为8.6±3岁（初次手术时）、15.1±1.8岁（毕业时）和17.8±1.6岁（末次随访时）。初次手术时最常见的LIV为L3（13/25）；13例中，选择STV作为LIV；7例中，选择NSTV；5例中，在标准正位X线片上选择SV。随访期间，平均LIV倾斜度（P = 0.049）和远端交界角（P = 0.017）显著增加。25例患者中有9例（36%）出现附加：LIV位于SV的患者中有20%（1/5）、位于STV的患者中有38.5%（5/13）、位于NSTV的患者中有42.8%（3/7）。在这9例附加病例中，只有4例需要远端延长（平均LIV倾斜度 = 17.6°）：2例STV患者（15.4%）和2例NSTV患者（28.6%）。LIV选择为SV的患者中，无一例因附加而需要远端延长。
在SV上方选择LIV的位置越高，随访期间附加和远端延长翻修手术的风险越高。选择STV作为LIV以保留运动节段可能是合理的，因为远端延长的需求不高，并且可以在延长手术期间或毕业手术时安排。
4级。
在TGR初次手术中选择正确的LIV对于获得稳固的远端基础、在生长过程中控制和纠正畸形以及保留远端节段以允许生长和活动至关重要。
