Children's Hospital Colorado, Aurora, CO United States.
Children's Hospital of Los Angeles, Los Angeles, CA United States.
J Pediatr Orthop. 2024;44(10):586-591. doi: 10.1097/BPO.0000000000002806. Epub 2024 Oct 9.
Magnetic controlled growth rods (MCGR) are the most common type of implant used for operative treatment of patients with early-onset scoliosis (EOS). Rods can have either a 7-cm actuator, allowing 2.8 cm of potential expansion, or a 9-cm actuator which allows 4.8 cm potential expansion. We hypothesized that the rate of unplanned return to the operating room (UPROR) will be increased when the 9-cm actuator is implanted in smaller patients. In addition, we aimed to identify a cutoff for spine length between planned upper and lower instrumented MCGR levels that best differentiated between patients having a high versus low risk of UPROR.
We identified 167 patients from a prospectively collected registry of EOS patients who began MCGR treatment at 9 years of age or younger, with greater than 1 year of follow-up, and had adequate radiographs. Demographic, clinical, and surgical characteristics were analyzed for 7-cm and 9-cm actuator patients. Chi-square tests and Student t tests were used to test for differences between the 2 actuator rod groups. A predictive model for UPROR within 2 years was developed based on variables significantly predictive of UPROR.
The average follow-up was 2.6 years (range, 1 to 5 y) in both the 7 cm (n=74) and 9 cm (n=93) groups. Twenty-five complications in 14 patients led to UPROR within 2 years of MCGR insertion, 8% incidence (95% CI, 4%-13%). Device-related complications (n=15) were the most common reason for UPROR, followed by wound complications (n=4), pain-related complications (n=3), junctional kyphosis (n=2), and incarcerated umbilical hernia (n=1). After adjusting for age, spine height, number of spine anchors, sex, and diagnosis, there was no significant difference in UPROR rates between groups. Fewer proximal anchors, smaller T1-S1 height, and more caudal mid-point of primary coronal curvature were significantly associated with UPROR in the predictive model.
MCGR actuator size is not a significant factor in predicted UPROR. Smaller height, fewer anchors, and caudal apex increased UPROR risk.
This is a retrospective, multicenter comparative cohort study (Level III therapeutic).
磁控生长棒（MCGR）是治疗早发性脊柱侧凸（EOS）患者的最常用植入物。棒可以有 7 厘米的执行器，允许 2.8 厘米的潜在扩张，或 9 厘米的执行器，允许 4.8 厘米的潜在扩张。我们假设，当在较小的患者中植入 9 厘米的执行器时，计划外返回手术室（UPROR）的比率会增加。此外，我们旨在确定计划上的上下仪器 MCGR 水平之间的脊柱长度的截止值，以最佳地区分具有高或低 UPROR 风险的患者。
我们从一个前瞻性收集的 EOS 患者登记处确定了 167 名患者，这些患者在 9 岁或以下开始 MCGR 治疗，随访时间大于 1 年，且有足够的影像学资料。对 7 厘米和 9 厘米执行器患者进行了人口统计学、临床和手术特征分析。使用卡方检验和学生 t 检验比较两组之间的差异。根据对 UPROR 有显著预测作用的变量，建立了 2 年内 UPROR 的预测模型。
7 厘米（n=74）和 9 厘米（n=93）两组的平均随访时间为 2.6 年（范围，1 至 5 年）。在 MCGR 插入后 2 年内，25 例并发症导致 14 例患者发生 UPROR，发生率为 8%（95%CI，4%-13%）。器械相关并发症（n=15）是 UPROR 最常见的原因，其次是伤口并发症（n=4）、疼痛相关并发症（n=3）、交界性后凸（n=2）和脐疝嵌顿（n=1）。在调整年龄、脊柱高度、脊柱锚定数量、性别和诊断后，两组 UPROR 发生率无显著差异。较小的近端锚定、较小的 T1-S1 高度和更尾侧的原发性冠状曲率中点与预测模型中的 UPROR 显著相关。
MCGR 执行器尺寸不是预测 UPROR 的重要因素。较小的高度、较少的锚定和尾侧顶点增加了 UPROR 的风险。
这是一项回顾性、多中心比较队列研究（III 级治疗）。
