Tabard-Fougère Anne, Rutz Dionys, Pouliot-Laforte Annie, De Coulon Geraldo, Newman Christopher J, Armand Stéphane, Wegrzyk Jennifer
Willy Taillard Laboratory of Kinesiology, Geneva University Hospitals and Geneva University, Geneva, Switzerland.
Physical Therapy Unit, Department of Clinical Neurosciences, Lausanne University Hospital, Lausanne, Switzerland.
Front Hum Neurosci. 2022 Mar 2;16:816088. doi: 10.3389/fnhum.2022.816088. eCollection 2022.
Intrinsic gait variability (GV), i.e., fluctuations in the regularity of gait patterns between repetitive cycles, is inherent to the sensorimotor system and influenced by factors such as age and pathology. Increased GV is associated with gait impairments in individuals with cerebral palsy (CP) and has been mainly studied based on spatiotemporal parameters. The present study aimed to describe kinematic GV in young people with CP and its associations with clinical impairments [i.e., passive range of motion (pROM), muscle weakness, reduced selective motor control (selectivity), and spasticity]. This retrospective study included 177 participants with CP (age range 5-25 years; Gross Motor Function Classification System I-III) representing 289 clinical gait analyses [ = 172 for unilateral CP (uCP) vs. 117 for bilateral CP (bCP)]. As variability metrics, Root Mean Square Deviation (RMSD) for nine lower-limb kinematic parameters and Gait Standard Deviation (GaitSD) - as composite score of the kinematic parameters - were computed for the affected (unilateral = uCP) and most affected side (bilateral = bCP), respectively, as defined by clinical scores. GaitSD was then computed for the non/less-affected side for between leg comparisons. Uni- and multivariate linear regressions were subsequently performed on GaitSD of the affected/most affected side with all clinical impairments (composite scores) as independent variables. Highest RMSD were found in the transverse plane (hip, pelvis), for distal joints in the sagittal plane (knee, ankle) and for foot progression. GaitSD was not different between uCP and bCP (affected/most affected side) but higher in the non-affected vs. affected side in uCP. GaitSD was associated with age ( < 0.001), gait deviation index (GDI) ( < 0.05), muscle weakness ( < 0.001), selectivity ( < 0.05), and pROM ( < 0.001). After adjustment for age and GDI, GaitSD remained associated with muscle weakness (uCP: = 0.003, bCP: < 0.001) and selectivity (bCP: = 0.024). Kinematic GV can be expressed as global indicator of variability (GaitSD) in young people with CP given the strong correlation of RMSD for lower-limb kinematic parameters. In terms of asymmetry, increased variability of the non-affected vs. affected side may indicate contralateral compensation mechanisms in uCP. Notably muscle weakness (uCP, bCP) and selectivity (bCP) - but not spasticity - were associated with GaitSD. Further studies need to explore the clinical relevance of kinematic GV in CP to support the interpretation of clinical gait analyses and therapeutic decision-making.
内在步态变异性（GV），即重复周期之间步态模式规律性的波动，是感觉运动系统所固有的，并受年龄和病理等因素影响。GV增加与脑瘫（CP）患者的步态障碍有关，并且主要基于时空参数进行研究。本研究旨在描述CP青年患者的运动学GV及其与临床损伤[即被动活动范围（pROM）、肌肉无力、选择性运动控制降低（选择性）和痉挛]的关联。这项回顾性研究纳入了177例CP患者（年龄范围5 - 25岁；粗大运动功能分类系统I - III级），代表289次临床步态分析[单侧CP（uCP）为172例，双侧CP（bCP）为117例]。作为变异性指标，分别针对受影响侧（单侧 = uCP）和受影响最严重侧（双侧 = bCP），计算九个下肢运动学参数的均方根偏差（RMSD）以及运动学参数的综合评分步态标准差（GaitSD），受影响侧由临床评分定义。然后计算非/受影响较小侧的GaitSD用于双腿间比较。随后以所有临床损伤（综合评分）作为自变量，对受影响/受影响最严重侧的GaitSD进行单因素和多因素线性回归分析。在横断面（髋、骨盆）、矢状面远端关节（膝、踝）以及足部前进方向发现最高的RMSD。uCP和bCP（受影响/受影响最严重侧）之间的GaitSD无差异，但uCP中未受影响侧的GaitSD高于受影响侧。GaitSD与年龄（<0.001）、步态偏差指数（GDI）（<0.05）、肌肉无力（<0.001）、选择性（<0.05）和pROM（<0.001）相关。在调整年龄和GDI后，GaitSD仍与肌肉无力（uCP：=0.003，bCP：<0.001）和选择性（bCP：=0.024）相关。鉴于下肢运动学参数的RMSD之间具有强相关性，运动学GV可表示为CP青年患者变异性的总体指标。就不对称性而言，未受影响侧与受影响侧相比变异性增加可能表明uCP中存在对侧补偿机制。值得注意的是，肌肉无力（uCP、bCP）和选择性（bCP）——而非痉挛——与GaitSD相关。进一步的研究需要探索CP中运动学GV的临床相关性，以支持临床步态分析的解读和治疗决策。
