External validation of the BABY-Knee Algorithm for treatment decision-making in skeletally immature patients with anterior cruciate ligament injuries: A Dutch cohort study

IF 3.2 Q2 ORTHOPEDICS

Journal of Experimental Orthopaedics Pub Date : 2026-08-18 DOI:10.1002/jeo2.70891

Annika Babette Ito, Rob Paulus Augustinus Janssen, Stijn Thomas Henricus Croes, Robin Nicolaas Julian Voskuilen, Alberto Grassi, Maria Christine van der Steen, Martijn Dietvorst

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引用次数: 0

Abstract

Purpose

The aim of this study was to investigate the external validity of the Best anterior cruciate ligament (ACL)-treatment Based on the Years of the Knee (BABY-Knee) Algorithm, developed based on an Italian population and to assess its applicability to a Dutch patient population treated in accordance with the 2018 International Olympic Committee (IOC) consensus statement.

Methods

A total of 109 skeletally immature patients with ACL injuries were included from the Dutch contribution to the European Society of Sport Traumatology, Knee Surgery and Arthroscopy (ESSKA) Paediatric Monitoring Initiative (PAMI). The BABY-Knee Algorithm was retrospectively applied to all patients, and corresponding scores were calculated. The predictive performance of the BABY-Knee Algorithm was assessed using the validation approach of the original validation study and an additional failure criterion based on hard clinical endpoints. Results were compared with the previously reported results.

Results

Of the 109 patients included, 78 (71.6%) were treated non-operatively, while the remaining 31 (28.4%) underwent operative treatment. However, according to the algorithm, 34 patients (31.2%) had a score of <3, indicating non-operative treatment, whereas 75 patients (68.8%) had a score of ≥3, indicating operative treatment. A statistically significant difference was observed between the algorithm's prediction and the performed treatment (p = 0.003). The original internal validation study reported a positive predictive value (PPV) of 91.7% and a negative predictive value (NPV) of 87.5%. In contrast, application of the BABY-Knee Algorithm to the present study population resulted in a PPV of 51.1% or 31.9% and an NPV of 64.5% or 67.7%, depending on the applied definition of failure.

Conclusion

The external validation of the BABY-Knee Algorithm showed inferior predictive performance compared with the original internal validation study in an Italian population. These findings suggest that the BABY-Knee Algorithm is not directly applicable to other populations of skeletally immature patients with ACL injuries.

Level of Evidence

Level III.

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婴儿-膝关节算法在前交叉韧带损伤骨骼不成熟患者治疗决策中的外部验证：荷兰队列研究。

目的：本研究的目的是调查基于膝关节年龄（BABY-Knee）算法的最佳前交叉韧带（ACL）治疗的外部有效性，该算法是基于意大利人群开发的，并评估其对荷兰患者群体的适用性，该患者群体按照2018年国际奥林匹克委员会（IOC）共识声明进行治疗。方法：从荷兰对欧洲运动创伤学、膝关节外科和关节镜学会（ESSKA）儿科监测倡议（PAMI）的贡献中，共纳入109例未成熟的前交叉韧带损伤患者。对所有患者回顾性应用BABY-Knee算法，并计算相应的评分。使用原始验证研究的验证方法和基于硬临床终点的额外失败标准来评估BABY-Knee算法的预测性能。结果与先前报道的结果进行比较。结果：109例患者中，非手术治疗78例（71.6%），手术治疗31例（28.4%）。然而，根据该算法，34例（31.2%）患者的评分为p = 0.003。最初的内部验证研究报告阳性预测值（PPV）为91.7%，阴性预测值（NPV）为87.5%。相比之下，将BABY-Knee算法应用于目前的研究人群，PPV为51.1%或31.9%，NPV为64.5%或67.7%，具体取决于所应用的失败定义。结论：在意大利人群中，与最初的内部验证研究相比，BABY-Knee算法的外部验证显示出较差的预测性能。这些发现表明BABY-Knee算法并不直接适用于其他未成熟的前交叉韧带损伤患者。证据等级：三级。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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