Background and Purpose—Dexterous object manipulation, requiring generation and control of finger forces, is often impaired after stroke. This study aimed to describe recovery of precision grip force control after stroke and to determine clinical and imaging predictors of 6-month performance.Methods—Eighty first-ever stroke patients with varying degrees of upper limb weakness were evaluated at 3 weeks, 3 months, and 6 months after stroke. Twenty-three healthy individuals of comparable age were also studied. The Strength-Dexterity test was used to quantify index finger and thumb forces during compression of springs of varying length in a precision grip. The coordination between finger forces (CorrForce), along with Dexterity-score and Repeatability-score, was calculated. Anatomical magnetic resonance imaging was used to calculate weighted corticospinal tract lesion load (wCST-LL).Results—CorrForce, Dexterity-score, and Repeatability-score in the affected hand were dramatically lower at each time point compared with the less-affected hand and the control group, even in patients with mild motor impairment according to Fugl-Meyer assessment. Improved performance over time occurred in CorrForce and Dexterity-score but not in Repeatability-score. The Fugl-Meyer assessment hand subscale, sensory function, and wCST-LL best predicted CorrForce and Dexterity-score status at 6 months (R²=0.56 and 0.87, respectively). wCST-LL explained substantial variance in CorrForce (R²=0.34) and Dexterity-score (R²=0.50) at 6 months; two-point discrimination and Fugl-Meyer score accounted for considerable additional variance. Absence of recovery in CorrForce was predicted by wCST-LL >4 cc and in Dexterity-score by wCST-LL >6 cc.Conclusions—Findings highlight persisting deficits in the ability to grasp and control finger forces after stroke. wCST-LL was the strongest predictor of performance at 6 months, but early two-point discrimination and Fugl-Meyer score had substantial additional predictive value.Registration—URL: https://www.clinicaltrials.gov. Unique identifier: NCT02878304.

中文翻译：

---

行程后动态精确抓地力控制的恢复和预测。

背景与目的—需要在手指产生和控制手指力的情况下进行各种物体操作，通常会在中风后对其进行削弱。这项研究旨在描述卒中后精确抓握力控制的恢复，并确定6个月表现的临床和影像学预测指标。方法-在3周，3个月时对80例上肢无力程度不同的首次卒中患者进行评估和中风后6个月。还研究了二十三个可比较年龄的健康个体。强度-灵活性测试用于量化精确握持中不同长度的弹簧压缩过程中的食指和拇指力。计算手指力（CorrForce）之间的协调度，以及敏捷得分和重复性得分。使用解剖磁共振成像来计算加权的皮质脊髓束病变负荷（wCST-LL）。与受影响程度较小的手相比，在每个时间点，患手的CorrForce，敏捷得分和重复性得分均显着降低。对照组，即使是根据Fugl-Meyer评估的轻度运动障碍患者。随着时间的推移，改进的性能出现在CorrForce和Dexterity得分中，而重复性得分则没有。Fugl-Meyer评估手部分量表，感觉功能和wCST-LL可以最佳预测6个月时的CorrForce和敏捷得分状态（R 即使根据Fugl-Meyer评估，即使是轻度运动障碍患者。随着时间的推移，改进的性能出现在CorrForce和Dexterity得分中，而重复性得分则没有。Fugl-Meyer评估手部分量表，感觉功能和wCST-LL可以最佳预测6个月时的CorrForce和敏捷得分状态（R 即使根据Fugl-Meyer评估，即使是轻度运动障碍患者。随着时间的推移，改进的性能出现在CorrForce和Dexterity得分中，而重复性得分则没有。Fugl-Meyer评估手部分量表，感觉功能和wCST-LL可以最佳预测6个月时的CorrForce和敏捷得分状态（R² = 0.56和0.87）。wCST-LL解释了6个月时CorrForce（R ² = 0.34）和敏捷得分（R ² = 0.50）的显着差异；两点歧视和Fugl-Meyer得分造成了较大的额外差异。wCST-LL> 4 cc预测CorrForce缺乏恢复，wCST-LL> 6 cc预测敏捷得分。结论—研究结果突显了中风后抓握和控制手指力的能力持续存在缺陷。wCST-LL是6个月时表现的最强预测指标，但早期的两点歧视和Fugl-Meyer评分具有更大的预测价值。注册网址：https：//www.clinicaltrials.gov。唯一标识符：NCT02878304。