The influence of 3D printed prostheses on neural activation patterns of the primary motor cortex in children with unilateral congenital upper-limb reductions

在美国，超过541，000人患有先天性上肢缩小或截肢。 全球上肢先天性缩小的估计范围为4-5/10，000至1/100活产婴儿。使用 身体动力上肢假肢帮助上肢缩小的儿童进行功能活动 对正常生长和运动发育至关重要。然而，假体的发展， 儿童由于其快速和持续的成长而变得复杂。高达58%的上肢复位儿童 由于体重过重、缺乏视觉吸引力、功能有限和复杂性而拒绝或放弃假肢 控制力3D打印假肢为开发轻量化、定制化的假肢提供了一种具有成本效益的解决方案 视觉上吸引儿童的假肢，可能会鼓励使用。从理论上讲，使用假肢 可能导致位于与运动有关的皮质区的初级神经元网络的扩大 控制受影响的肢体。最终，这可能会导致更大的运动策略和整合 将假体的运动控制转化为儿童的运动控制，从而促进假体的接受。但是，很少或 没有证据支持这一假设。儿童运动成绩的神经基础 假体研究严重不足，导致经验证据极少。这主要是由于i） 在该儿科人群中观察到较高的假体排斥率和废弃率， 监测使用假肢前后的行为或神经变化，以及ii） 传统的神经成像技术，如功能性磁共振成像（fMRI）， 脑电图（EEG），用于评估儿科人群的脑功能。功能接近- 红外光谱（fNIRS）已成为一种对噪声不太敏感的实用神经成像技术 与脑电图和功能磁共振成像相比，它更容易让孩子们忍受测试。FNIRS在 结合定制和视觉上吸引人的3D打印假体将提供独特的机会 定量评估上肢假体对主动脉神经激活模式的影响， 运动皮层和儿童运动表现。我们的初步研究表明，大脑皮层激活减少， 更有效的运动反应，并在长时间使用3D打印上肢后提高协调性 假肢这项研究将确定使用假体对神经激活模式的影响。 单侧先天性部分手缩小儿童的初级运动皮层中心假设是 长期使用假体将导致初级皮质激活减少，这表明佩戴假体 可以帮助初级运动皮层产生更精细、专门和有效的运动皮层反应 改善假体的运动性能和功能使用。

In the United States, more than 541,000 individuals live with congenital upper-limb reductions or amputations. Worldwide estimates for upper-limb congenital reductions range from 4-5/10,000 to 1/100 live births. The use of body-powered upper-limb prostheses helps children with upper-limb reductions to engage in functional activities that are fundamental to normal growth and motor development. However, the development of prostheses for children is complex due to their rapid and continuous growth. Up to 58% of children with upper-limb reductions reject or abandon their prosthesis due to excessive weight, lack of visual appeal, limited function and complexity of control. 3D printed prostheses provide a cost-effective solution to the development of light-weight, customized and visually appealing prostheses for children, potentially encouraging use. Theoretically, the use of a prosthesis may lead to an enlargement of the primary neuronal networks located in the cortical area involved with motor control of the affected limb. Ultimately, this might lead to a larger repertoire of motor strategies and integration of the prosthesis into the motor control of the child facilitating prosthesis acceptance. However, there is little or no evidence supporting this hypothesis. The neural basis underlying motor performance in children using a prosthesis has been severely understudied resulting in minimal empirical evidence. This is largely due to i) the high prosthesis rejection rate and abandonment observed in this pediatric population making it difficult to properly monitor behavioral or neural changes before and after using a prosthesis, and ii) technological constraints of traditional neuroimaging techniques, such as functional magnetic resonance imaging (fMRI) and electroencephalography (EEG), in the assessment of brain function of pediatric populations. Functional near- infrared spectroscopy (fNIRS) has emerged as a practical neuroimaging technique that is less sensitive to noise and movement artifacts than EEG and fMRI, making it easier for children to tolerate testing. The use of fNIRS in conjunction with customized and visually appealing 3D printed prostheses would provide the unique opportunity to quantitatively assess the influence of upper-limb prostheses in the neural activation patterns of the primary motor cortex and motor performance of children. Our pilot work has shown a reduction of cortical activation, a more efficient motor response, and increased coordination after prolonged use of a 3D printed upper-limb prosthesis. This study will determine the influence of using a prosthesis on the neural activation patterns of the primary motor cortex in children with unilateral congenital partial hand reductions. The central hypothesis is that prolonged prosthesis use will result in a reduced primary cortex activation indicating that wearing a prosthesis may assist the primary motor cortex to produce a more refined, specialized, and efficient motor cortex response improving motor performance and the functional use of the prosthesis.