Pediatric Orthopedics, Deformity Reconstruction and Foot Surgery, Muenster University Hospital; General Orthopedics and Tumor Orthopedics, Muenster University Hospital, Germany.
Pediatric Orthopedics, Deformity Reconstruction and Foot Surgery, Muenster University Hospital.
Acta Orthop. 2024 Jul 15;95:364-372. doi: 10.2340/17453674.2024.40947.
Magnetically controlled motorized intramedullary lengthening nails (ILNs) can be employed for simultaneous correction of angular deformities of the distal femur and leg length discrepancy. This spares typical complications of external fixators but requires precise preoperative planning and exact intraoperative execution. To date, its results are insufficiently reported. We aimed to elucidate the following questions: (i) Is acute angular deformity correction and gradual femoral lengthening via a retrograde ILN a reliable and precise treatment option? (ii) What are the most common complications of treatment?
Acute angular deformity correction and subsequent gradual lengthening of the distal femur with retrograde ILN was retrospectively analyzed in 45 patients (median patient age: 15 years, interquartile range [IQR] 13-19 and median follow-up: 40 months, IQR 31-50). Outcome parameters were accuracy, precision, reliability, bone healing, and complications of treatment.
The median distraction was 46 mm (IQR 29-49), median distraction and consolidation index 0.9 mm/day (IQR 0.7-1.0) and 29 days/cm (IQR 24-43), respectively. The median preoperative mechanical axis deviation (MAD) was 30 mm (IQR 23-39) in the varus cohort and -25 mm (IQR -29 to -15) in the valgus cohort and reduced to a mean of 8 mm (standard deviation [SD] 8) and -3 (SD 10), respectively. Accuracy, precision, and reliability of lengthening were 94%, 95% and 96%, respectively. Accuracy and precision of deformity correction were 92% and 89%, respectively. In total, 40/45 of patients achieved distraction with a difference of less than 1 cm from the initial plan and a postoperative MAD ranging from -10 mm to +15 mm. In 13/45 patients unplanned additional surgeries were conducted to achieve treatment goal with nonunion being the most frequent (4/45) and knee subluxation (3/45) the most severe complication.
Acute deformity correction and subsequent lengthening of the distal femur with retrograde ILN is a reliable and accurate treatment achieving treatment goal in 89% but unplanned additional surgeries in 29% of patients should be anticipated.
磁控机动髓内延长钉（ILN）可用于同时矫正股骨远端的成角畸形和肢体长度差异。这种方法避免了典型的外固定器并发症，但需要精确的术前规划和准确的术中执行。迄今为止，其结果报告不足。我们旨在阐明以下问题：（i）通过逆行 ILN 进行急性成角畸形矫正和逐渐股骨延长是否是一种可靠和精确的治疗选择？（ii）治疗的最常见并发症是什么？
回顾性分析了 45 例（中位患者年龄：15 岁，四分位距 [IQR] 13-19 岁，中位随访时间：40 个月，IQR 31-50 个月）采用逆行 ILN 急性矫正成角畸形并随后逐渐延长股骨远端的患者。观察指标包括准确性、精度、可靠性、骨愈合和治疗并发症。
平均延长距离为 46mm（IQR 29-49），平均延长和骨整合指数分别为 0.9mm/天（IQR 0.7-1.0）和 29 天/cm（IQR 24-43）。术前机械轴偏差（MAD）中位数在 30mm（IQR 23-39）的内翻组和-25mm（IQR-29 至-15）的外翻组，分别减少到平均 8mm（标准差 [SD] 8）和-3mm（SD 10）。延长的准确性、精度和可靠性分别为 94%、95%和 96%。成角畸形矫正的准确性和精度分别为 92%和 89%。总的来说，45 例患者中有 40 例实现了与初始计划相差小于 1cm 的延长，术后 MAD 范围从-10mm 到+15mm。在 13 例患者中，计划外的附加手术用于实现治疗目标，其中不愈合是最常见的（4/45），膝关节半脱位（3/45）是最严重的并发症。
逆行 ILN 急性矫正和随后的股骨远端延长是一种可靠且准确的治疗方法，可使 89%的患者达到治疗目标，但 29%的患者需要计划外的附加手术。
