Cohen Lara L, Yang Brian W, O'Neill Nora P, Proctor Mark R, Glotzbecker Michael P, Hedequist Daniel J
Departments of1Orthopaedic Surgery and.
2Neurosurgery, Harvard Medical School/Boston Children's Hospital, Boston, Massachusetts.
J Neurosurg Pediatr. 2020 Jan 31;25(5):535-539. doi: 10.3171/2019.11.PEDS19622. Print 2020 May 1.
Patients with trisomy 21 (Down syndrome; DS) often have atlantoaxial instability (AAI), which, if severe, causes myelopathy and neurological deterioration. Children with DS and AAI who undergo cervical spine fusion have a high rate of nonunion requiring revision surgery. Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a TGF-β growth factor that is used to induce bone formation in spine fusion. Although previous studies in the adult population have reported no reduction in pseudarthrosis rates with the use of rhBMP-2, there is a lack of literature in the pediatric DS population. This study describes the use of rhBMP-2 in children with DS and AAI during revision to treat nonunion.
A retrospective review of a cervical spine fusion database (n = 175) was conducted. This database included all cervical spine fusions using modern instrumentation at the authors' institution from 2002 to 2019. Patients with DS who underwent a revision utilizing rhBMP-2 were included in the study. The number of prior fusions, use of rhBMP-2 in fusions, length of stay, halo use, and surgical data were collected. Postoperative complications and length of follow-up were also recorded.
Eight patients (75% female) met the inclusion criteria. The average age at revision with rhBMP-2 was 11 years (range 3-19 years). All patients were diagnosed with nonunion after an initial cervical fusion. All revisions were posterior fusions of C1-2 (n = 2) or occiput to cervical (n = 6). All revisions included implant revisions, iliac crest bone grafting, and rhBMP-2 use. One patient required irrigation and debridement of an rhBMP-induced seroma. Another patient required return to the operating room to repair a dural tear. There were no neurological, infectious, airway, or implant-related complications. Revision utilizing rhBMP-2 achieved fusion in 100% (n = 8) of patients. The average length of follow-up was 42.6 months. All patients demonstrated solid fusion mass on the last radiograph.
This is the first case series reporting the successful use of rhBMP-2 to facilitate cervical spine fusion in patients with DS after previous nonunion. In addition, few rhBMP-2-related postoperative complications occurred.
21三体综合征（唐氏综合征；DS）患者常伴有寰枢椎不稳（AAI），严重时可导致脊髓病和神经功能恶化。患有DS和AAI的儿童接受颈椎融合手术后，骨不连发生率很高，需要进行翻修手术。重组人骨形态发生蛋白-2（rhBMP-2）是一种转化生长因子-β，用于诱导脊柱融合中的骨形成。尽管此前针对成年人群的研究报告称，使用rhBMP-2并未降低假关节形成率，但儿科DS人群中缺乏相关文献。本研究描述了rhBMP-2在患有DS和AAI的儿童翻修手术中用于治疗骨不连的情况。
对一个颈椎融合数据库（n = 175）进行回顾性分析。该数据库包括了作者所在机构在2002年至2019年期间使用现代器械进行的所有颈椎融合手术。本研究纳入了接受使用rhBMP-2进行翻修手术的DS患者。收集了既往融合手术次数、融合手术中rhBMP-2的使用情况、住院时间、头环使用情况及手术数据。还记录了术后并发症及随访时间。
8例患者（75%为女性）符合纳入标准。使用rhBMP-2进行翻修手术时的平均年龄为11岁（范围3 - 19岁）。所有患者在初次颈椎融合术后均被诊断为骨不连。所有翻修手术均为C1 - 2后路融合（n = 2）或枕颈后路融合（n = 6）。所有翻修手术均包括植入物翻修、髂嵴植骨及rhBMP-2的使用。1例患者需要对rhBMP诱导的血清肿进行冲洗和清创。另1例患者需要返回手术室修复硬脑膜撕裂。未发生神经、感染、气道或植入物相关并发症。使用rhBMP-2进行翻修手术的患者融合成功率达100%（n = 8）。平均随访时间为42.6个月。所有患者在最后一次影像学检查中均显示有坚实的融合块。
这是首个报道成功使用rhBMP-2促进既往骨不连的DS患者颈椎融合的病例系列。此外，rhBMP-2相关的术后并发症很少发生。
