背景：选择性电机控制（SMC）是典型人体运动的基本组成部分。由于脑损伤,受损的SMC往往导致协调困难，balance,步态效率和对称性。
目的：SMC受损与下肢运动能力有什么关联，双侧痉挛型脑瘫（CP）儿童的功能平衡和步态表现？
方法：在粗大运动功能分类系统（GMFCS）I至II级中，36名患有痉挛型双侧CP的儿童（5-16岁）被纳入本研究。使用下肢选择性对照评估(SCALE)评估SMC。使用粗大运动功能测量-88项目D和E维度(GMFM-88D&E)评估粗大运动功能。使用儿科平衡量表(PBS)和定时向上并进行测试(TUG)评估功能平衡。使用爱丁堡视觉步态评分（EVGS）和10米步行测试（10MWT）评估步态质量。Spearman的等级相关分析用于确定SMC与其他因素之间的关联。
结果：相关分析表明，SCALE与GMFM-88（D＆E）呈强烈正相关（rs=0.756，p<0.001），PBS（rs=0.769，p<0.001），和身高归一化的快速步行速度(rs=0.632，p<0.001)，与TUG（rs=-0.766，p<0.001）和EVGS（rs=-0.893，p<0.001）呈显著负相关。
结论：下肢SMC缺陷与粗大运动功能和平衡控制不良有关，双侧痉挛型CP患儿的整体步态偏差更严重，步行速度更快。物理疗法应包括促进选择性运动控制的干预措施，以提高整体功能能力。
Selective motor control (SMC) is a fundamental component of typical human motion. As a result of brain damage, impaired SMC often leads to difficulties with coordination, balance, gait efficiency and symmetry.
What is the association between impaired SMC and lower limb motor ability, functional balance and gait performance in children with bilateral spastic cerebral palsy (CP)?
Thirty-six children (aged 5-16 years) with spastic bilateral CP in Gross Motor Function Classification System (GMFCS) level I to II were included in this study. SMC was assessed using Selective Control Assessment of the Lower Extremity (SCALE). Gross motor function was assessed using Gross Motor Function Measure-88 items D and E dimension (GMFM-88 D&E). Functional balance was assessed using Pediatric Balance Scale (PBS) and Timed Up and Go Test (TUG). Gait quality was assessed using Edinburg Visual Gait Score (EVGS) and 10-Meter Walk Test (10MWT). Spearman\'s rank correlation analyses were used to determine the association between SMC and other factors.
Correlation analyses showed that SCALE was strongly positively correlated with GMFM-88 (D&E) (rs=0.756, p < 0.001), PBS (rs=0.769, p < 0.001), and height-normalized fast walking speed (rs=0.632, p < 0.001), and strongly negatively correlated with TUG (rs=-0.766, p < 0.001) and EVGS (rs=-0.893, p < 0.001).
Lower extremity SMC deficits are associated with poor gross motor function and balance control, more severe overall gait deviations and decreased fast walking speed in children with bilateral spastic CP. Physical therapy should include interventions that promote selective motor control in order to improve overall functional ability.
