Yazici Muharrem, Akel Ibrahim, Demirkiran Halil Gokhan
J Child Orthop. 2011 Feb;5(1):55-61. doi: 10.1007/s11832-010-0322-2. Epub 2011 Jan 1.
Patients with lumbosacral agenesis characteristically sit on their iliac wings with their torsos bent forward, which yields an increase in intra-abdominal pressure and, subsequently, negative effects on their diaphragm. The sacrum is not available as an anchor point for instrumentation. Dunn-McCarthy rods or Galveston fixations cannot be performed due to these limited anatomic properties. On the other hand, the absence of necessary bone mass for fusion anteriorly limits the fusion interventions to the posterior. Therefore, a secure and rigid fixation is essential to preclude the need for an external support. There are limited publications discussing different techniques due to the relatively rare incidence of the disease. We report the clinical and radiological results of a new technique applied to three patients in which previously recommended methods are modified.
Two 6-year-old female patients and one 5-year-old male patient with lumbosacral agenesis underwent posterior lumbopelvic instrumentation and fusion. Together with standard pedicle screw spinal instrumentation, pelvic fixation is obtained with a combination of supero-inferior directed rod and/or screw to overcome deforming forces created at the flexion-extension pivot points of the lumbopelvic junction. Autogenic anterior tibial cortical structural graft is used for laminopelvic bridging, and demineralized bone matrix is used for the augmentation of osteoinduction. A single leg hip spica is applied for 4 months to protect the fixation.
Total correction yielded an aligned spine with a posture that allows for sitting on the ischial spines for all three patients. Solid fusion was observed to maintain this correction at the final follow-up.
The use of new-generation pediatric spinal instrumentation systems with a new technique without knee disarticulation provides a safe and effective fixation and fusion in lumbosacral agenesis.
腰骶部发育不全的患者通常以躯干向前弯曲的姿势坐在髂骨翼上，这会导致腹内压升高，进而对其膈肌产生负面影响。骶骨无法作为器械固定的锚定点。由于这些有限的解剖特性，无法进行邓恩 - 麦卡锡棒或加尔维斯顿固定。另一方面，前方缺乏融合所需的骨量限制了融合干预仅能在后方进行。因此，牢固而稳定的固定对于避免使用外部支撑至关重要。由于该疾病发病率相对较低，讨论不同技术的出版物有限。我们报告了应用于三名患者的一种新技术的临床和放射学结果，该技术对先前推荐的方法进行了改进。
两名6岁女性患者和一名5岁男性患者患有腰骶部发育不全，接受了后路腰骶骨盆器械固定和融合术。除了标准的椎弓根螺钉脊柱器械固定外，通过上下方向的棒和/或螺钉组合来获得骨盆固定，以克服在腰骶关节屈伸枢轴点产生的变形力。自体胫骨前皮质结构骨移植用于椎板骨盆桥接，脱矿骨基质用于增强骨诱导。应用单腿髋人字石膏固定4个月以保护固定。
完全矫正使所有三名患者的脊柱排列整齐，姿势允许坐在坐骨棘上。在最后一次随访时观察到坚实的融合维持了这种矫正。
使用新一代儿科脊柱器械系统并采用一种不进行膝关节离断的新技术，可为腰骶部发育不全提供安全有效的固定和融合。
