Purpose

Voluntary femoro-tibial subluxation is a rare entity predominantly found in pretoddlers. It presents as a dynamic phenomenon with uni- or bilateral audible snapping of the knee, often in a context of fatigue or irritation at the end of the day. The aim of the study was to observe the evolution and recovery in these patients.

Methods

Ten children were included. Other causes of dislocating joints and pathologies with snapping of the lateral meniscus were excluded from this study. Six-week immobilisation with a splint at 70° of knee flexion was primarily recommended to all patients.

Results

The mean age at onset of symptoms was 10 months. Forty percent of the patients presented with bilateral symptoms. Clinically, four patients were hyperlax. In all patients, subluxations could be reproduced passively by rotating the foot externally and advancing the internal tibial plateau anteriorly. Three of the patients were treated with a dorsal splint and experienced significantly less or cessation of symptoms. Two patients underwent surgery, one for a concomitant anterior cruciate ligament (ACL) rupture and meniscus tear that worsened the symptoms, another for concomitant patella dislocation and a meniscus tear. One patient’s parents refused treatment and four patients experienced less symptoms at the time of consultation and were not immobilized. Except for the two patients undergoing surgeries, no sequelae were observed. In general, the symptoms got less frequent when the patient began to walk.

Conclusion

Voluntary femoro-tibial subluxation in children is a rare and benign condition that often resolves spontaneously without sequelae. The risk of meniscus tear should, however, be considered if subluxations do not cease.

Level of evidence

IV.

中文翻译：

---

自愿性股胫半脱位：儿童膝关节snap裂的良性鉴别诊断。

目的

自愿性股胫半脱位是一种罕见的个体，主要存在于幼儿中。它表现为一种动态现象，通常在一天结束时出现疲劳或刺激的情况下，膝盖出现单侧或双侧可听见的snap啪声。该研究的目的是观察这些患者的进化和恢复。

方法

包括十个孩子。本研究排除了因半月板弯折引起的关节脱位和病理的其他原因。对于所有患者，主要推荐在70°屈膝时用夹板固定6周。

结果

症状发作的平均年龄为10个月。40％的患者出现双侧症状。临床上有四例患者松弛。在所有患者中，可以通过向外旋转脚并向前推动胫骨内侧平台来被动复制半脱位。其中三名患者接受了背板夹板治疗，症状明显减轻或停止。两名患者接受了手术，一名因前交叉韧带（ACL）破裂和半月板撕裂而使症状恶化，另一名因for骨脱位和半月板撕裂而接受手术。一位患者的父母拒绝了治疗，四位患者在咨询时症状减轻并且没有固定。除两名接受手术的患者外，未观察到任何后遗症。一般来说，

结论

儿童自愿性股骨半脱位是一种罕见的良性疾病，通常会自发消退而没有后遗症。但是，如果半脱位不停止，则应考虑半月板撕裂的风险。

证据水平

IV。