Most clinical tools for measuring spasticity, such as the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale (MTS), are not sufficiently accurate or reliable. This study investigated the clinimetric properties of an instrumented spasticity assessment. Twenty-eight children with spastic cerebral palsy (CP) and 10 typically developing (TD) children were included. Six of the children with CP were retested to evaluate reliability. To quantify spasticity in the gastrocnemius (GAS) and medial hamstrings (MEH), three synchronized signals were collected and integrated: surface electromyography (sEMG); joint-angle characteristics; and torque. Muscles were manually stretched at low velocity (LV) and high velocity (HV). Spasticity parameters were extracted from the change in sEMG and in torque between LV and HV. Reliability was determined with intraclass-correlation coefficients and the standard error of measurement; validity by assessing group differences and correlating spasticity parameters with the MAS and MTS. Reliability was moderately high for both muscles. Spasticity parameters in both muscles were higher in children with CP than in TD children, showed moderate correlation with the MAS for both muscles and good correlation to the MTS for the MEH. Spasticity assessment based on multidimensional signals therefore provides reliable and clinically relevant measures of spasticity. Moreover, the moderate correlations of the MAS and MTS with the objective parameters further stress the added value of the instrumented measurements to detect and investigate spasticity, especially for the GAS.

For all motor and sensory assessments, interrater and test-retest reliability was moderate to very high. Test-retest reliability was clearly higher than interrater reliability. To improve interrater reliability, it was recommended to strictly standardize the test procedure, refine the scoring criteria and provide intensive rater trainings.

The present study documents the correlation between gait analysis data and clinical measurements and evaluates the combined predictive value of static and dynamic clinical measurements on gait data of children with cerebral palsy. Two hundred patients were evaluated using a set of measurements of range of motion (ROM), alignment, spasticity, strength and selectivity, and by three-dimensional gait analysis. Fair to moderate correlations were found between clinical measurements and gait data, the overall highest correlation being 0.60. Clinical data of strength and selectivity had the highest degree of significant correlations with gait data, compared to the ROM and spasticity. ROM, spasticity and strength measurements for the hip in the coronal plane and spasticity of rectus femoris most frequently showed fair to moderate correlations to gait data. Time and distance and EMG parameters mainly correlated with strength and selectivity parameters. Unexpectedly, alignment parameters only fairly correlated with hip rotation in stance. Multiple regression analysis revealed that adding dynamic clinical measurements (spasticity, strength and selectivity) to a static model (ROM) enhanced the link between clinical measurements and gait data. The variance of gait parameters was better explained by a combined model of static and dynamic clinical measurements, compared to a purely static model. However, R 2 -values were low. Gait analysis data cannot be sufficiently predicted by a combination of clinical measurements. The independence of the measurements supports the notion that both, clinical examination and gait analysis data provide important information for delineating the problems of children with CP. #

Several studies indicated that walking with an ankle foot orthosis (AFO) impaired third rocker. The purpose of this study was to evaluate the effects of two types of orthoses, with similar goal settings, on gait, in a homogeneous group of children, using both barefoot and shoe walking as control conditions. Fifteen children with hemiplegia, aged between 4 and 10 years, received two types of individually tuned AFOs: common posterior leaf-spring (PLS) and Dual Carbon Fiber Spring AFO (CFO) (with carbon fibre at the dorsal part of the orthosis). Both orthoses were expected to prevent plantar flexion, thus improving first rocker, allowing dorsiflexion to improve second rocker, absorbing energy during second rocker, and returning it during the third rocker. The effect of the AFOs was studied using objective gait analysis, including 3D kinematics, and kinetics in four conditions: barefoot, shoes without AFO, and PLS and CFO combined with shoes. Several gait parameters significantly changed in shoe walking compared to barefoot walking (cadence, ankle ROM and velocity, knee shock absorption, and knee angle in swing). The CFO produced a significantly larger ankle ROM and ankle velocity during push-off, and an increased plantar flexion moment and power generation at pre-swing compared to the PLS (<0.01). The results of this study further support the findings of previous studies indicating that orthoses improve specific gait parameters compared to barefoot walking (velocity, step length, first and second ankle rocker, sagittal knee and hip ROM). However, compared to shoes, not all improvements were statistically significant.

The instrumented spasticity assessment showed higher responsiveness than the clinical scales. The amount of RMS electromyography is considered a promising parameter to predict treatment response.