Sun Zhijian, Qiu Guixing, Zhao Yu, Wang Yipeng, Zhang Jianguo, Shen Jianxiong
Department of Orthopaedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Dongcheng District Shuaifuyuan No. 1, Beijing, 100730, China.
Eur Spine J. 2014 Jun;23(6):1251-7. doi: 10.1007/s00586-014-3276-0. Epub 2014 Mar 25.
To determine fusion necessity to one level below lower-end vertebra (LEV+1) in selective posterior fusion of moderate thoracolumbar/lumbar (TL/L) idiopathic scoliosis.
A total of 37 patients with moderate TL/L idiopathic scoliosis (Cobb angle of TL/L curve between 30° and 60°) were identified and three patients with TL/L curve Cobb angle more than 60° were excluded. And the follow-up period was at least 2 years. Lowest instrumented vertebra (LIV) was one level proximal to LEV in three patients, LEV in 22 patients and LEV+1 in 12 patients. The three patients with TL/L Cobb angle more than 60° were all fused to LEV+1. Clinical and various radiographic measurements were collected before surgery, post-surgery and during last follow-up, and analytical comparisons were made between LIV = LEV patients and LIV = LEV+1 patients.
No significant difference was observed regarding clinical and radiographic parameters between LEV group and LEV+1 group preoperatively except LIV disc angle and LIV translation. The correction rate of unfused thoracic curve and TL/L curve was 52.7 and 79.9 % in LEV group and 52.5 and 83.7 % in LEV+1 group at the last follow-up, indicating no significant difference (P = 0.976 and P = 0.415, respectively). Coronal balance and sagittal alignments were also comparable between the two groups. LIV translation was slightly less in LEV+1 group (P = 0.028) at the last follow-up on the basis that LEV+1 was less translated than LEV preoperatively.
Our analysis almost showed no benefit for fusing to LEV+1 in moderate TL/L idiopathic scoliosis patients undergoing posterior selective fusion with pedicle screws. For patients with TL/L Cobb angle more than 60°, the distal fusion level probably needs to be LEV+1.
确定中度胸腰段/腰椎（TL/L）特发性脊柱侧凸选择性后路融合术中融合至下端椎（LEV）以下一个节段（LEV+1）的必要性。
共纳入37例中度TL/L特发性脊柱侧凸患者（TL/L曲线Cobb角在30°至60°之间），排除3例TL/L曲线Cobb角大于60°的患者。随访期至少2年。3例患者的最低固定椎（LIV）为LEV近端一个节段，22例患者为LEV，12例患者为LEV+1。3例TL/L Cobb角大于60°的患者均融合至LEV+1。收集术前、术后及末次随访时的临床和各种影像学测量数据，并对LIV = LEV组和LIV = LEV+1组进行分析比较。
术前LEV组和LEV+1组除LIV椎间盘角度和LIV平移外，临床和影像学参数无显著差异。末次随访时，LEV组未融合胸段曲线和TL/L曲线的矫正率分别为52.7%和79.9%，LEV+1组分别为52.5%和83.7%，差异无统计学意义（P分别为0.976和0.415）。两组冠状面平衡和矢状面排列也具有可比性。末次随访时，基于术前LEV+1的平移小于LEV，LEV+1组的LIV平移略少（P = 0.028）。
我们的分析几乎表明，对于接受椎弓根螺钉后路选择性融合的中度TL/L特发性脊柱侧凸患者，融合至LEV+1并无益处。对于TL/L Cobb角大于60°的患者，远端融合节段可能需要为LEV+1。
