Sensorimotor integration underlying hand control in Carpal Tunnel Syndrome

物体抓取和操纵的有效控制依赖于个体力量的调节能力 数字与被抓物体的属性，如重量、质心或质地。这些 调整依赖于（a）通过主要来自受体的感觉反馈来检测对象特性 以及（B）将该反馈与手部肌肉的激活相结合 适合抓握和操作。然而，手部肌肉活动对物体的微调 一些神经和肌肉骨骼疾病，如腕管综合征， 综合征（CTS）。这种正中神经的扩张性神经病是最常见的， 影响手功能的衰弱性疾病。CTS导致自我报告的手部灵活性丧失（例如， 精细操作困难、掉落物体等）这是由于拇指的躯体感觉缺陷， 无名指的食指、中指和侧半部分，在严重的情况下，拇指的运动缺陷。整体而言- 手抓握需要从所有手指感知物体属性，以准确地调整它们的力量， CTS提供了一个独特的机会，以提高我们的理解机制的感觉运动 在全手抓握和操作过程中的整合。这一主要目标将通过使用 CTS作为一个研究模型，以解决这些重要的问题的感觉运动控制的把握。一个 另一个次要目标是利用拟议研究的结果来提高我们的认识 神经功能受损程度的增加影响感觉运动转换 学习和执行熟练的对象操作的特定方面所必需的。 我们将追求两个具体目标：（1）量化CTS患者能够在多大程度上 协调所有手指的力量和接触点时，改变对象属性（质心，重量和 纹理）及其在五指抓握期间的可预测性;以及（2）确定患者 CTS能够协调手指力量作为手指数量的函数（2、3、4和5） 参与了抓。在这两个目标中，对轻度和重度抑郁症患者的抓握控制进行了多维测量， 将中重度CTS与从年龄和性别匹配的健康对照中获得的那些进行比较。拟议研究的目标与公共卫生有关，因为它们涉及 一种使人衰弱的手部神经肌肉疾病，腕管综合征（CTS）， 影响了美国600万到1400万成年人的生活质量。我们建议使用 CTS作为一种模型，以提高我们对潜在机制的理解 负责熟练的物体操作的感觉运动整合。知识 通过我们提出的研究获得的信息将提供重要的洞察力， 神经功能的电诊断测量涉及抓握控制的特定方面， 从而改进这些临床测量的可解释性和应用。

Effective control of object grasping and manipulation relies on the ability to adjust forces of individual digits to the properties of the object being grasped such as its weight, center of mass or texture. These adjustments rely on (a) detecting object properties through sensory feedback derived primarily from receptors in the fingertips and hand muscles and (b) integrating this feedback with activation of hand muscles appropriate for grasping and manipulation. However, the fine tuning of hand muscle activity to object properties can be disrupted by a number of neurological and musculo-skeletal diseases such as Carpal Tunnel Syndrome (CTS). This compresion neuropathy of the median nerve is one of the most common and debilitating diseases affecting hand function. CTS results in self-reported loss of manual dexterity (e.g., difficulties with fine manipulation, dropping objects, etc.) which is due to somatosensory deficits in the thumb, index, middle and lateral half of the ring finger, and, in severe cases, motor deficits in the thumb. As whole- hand grasping require sensing object properties from all digits to accurately adjust their forces, the study of CTS offers a unique opportunity to improve our understanding the mechanisms underlying sensorimotor integration during whole-hand grasping and manipulation. This primary objective will be pursued by using CTS as a research model to address these important questions of sensorimotor control of grasping. An additional secondary objective is to use the results of the proposed research to improve our understanding of the extent to which increasing impairment in nerve function affects sensorimotor transformations necessary for learning and executing specific aspects of skilled object manipulation. We will pursue two Specific Aims: (1) to quantify the extent to which patients with CTS are able to coordinate all digit forces and contact points when altering object properties (center of mass, weight and texture) and their predictability during five-digit grasping; and (2) to determine the extent to which patients with CTS are able to coordinate digit forces as a function of the number of digits (two, three, four, and five) involved in the grasp. In both Aims, multi-dimensional measures of grasp control from patients with mild and moderately severe CTS will be compared with those obtained from age- and gender-matched healthy controls. The objectives of the proposed research are relevant to public health as they address a debilitating neuromuscular disease of the hand, Carpal Tunnel Syndrome (CTS), that affects the quality of life in 6 to 14 million adults in the United States. We propose to use CTS as a model to improve our understanding of the mechanisms underlying sensorimotor integration responsible for skilled object manipulation. The knowledge gained through our proposed research will provide significant insight into how electrodiagnostic measures of nerve function relate to specific aspects of grasp control, thus improving the interpretability and applications of these clinical measures.