Obstacle Crossing During Gait in Children With Cerebral Palsy: Cross-Sectional Study With Kinematic Analysis of Dynamic Balance and Trunk Control.

Balance problems are common in children who have cerebral palsy (CP) but are active and ambulant. Control of the whole-body center of mass is critical in maintaining dynamic stability during challenging mobility tasks, such as clearing an obstacle while walking. The objective of this study was to compare trunk and lower limb kinematics and center-of-mass control in children with CP and those in children with typical development during obstacle crossing. This was a cross-sectional study. Thirty-four children who were 5 to 17 years of age (17 with CP and 17 with typical development) and matched in age and height completed 2 gait trials involving crossing a 10-cm obstacle. Three-dimensional kinematic and kinetic data were captured with a general-purpose 3-dimensional motion tracking system and forceplates. Trunk data were captured with a validated model. All children cleared the obstacle with similar hip and knee kinematics, step length, and single-support duration. In children with CP, step width was increased by 4.81 cm, and center-of-mass velocity was significantly slower at lead limb toe-off (0.31 m/s) and during lead limb clearance (0.2 m/s). Children with CP showed altered trunk and pelvis movement, characterized by significantly greater pelvic obliquity, pelvic tilt, and trunk rotation throughout the task, increased lateral trunk lean during lead limb crossing (3.7°), and greater sagittal trunk movement as the trail limb crossed (5.1°). The study was not powered to analyze differences between children with diplegia and those with hemiplegia. Children with CP required greater adjustments at the trunk and pelvis to achieve successful obstacle crossing. The increase in trunk movement could have been compensatory for reduced stability distally or for a primary problem reflecting poor proximal control. The findings suggest that rehabilitation should focus on both proximal trunk control and distal stability to improve balance.

Malone A ，Kiernan D ，French H ，Saunders V ，O'Brien T ... -  《-》

Do children with cerebral palsy change their gait when walking over uneven ground?

Independently ambulant children with Cerebral Palsy (CP) often report balance difficulties when walking in challenging settings. The aim of this study was to compare gait in children with CP to typically developing (TD) children walking over level ground and uneven ground, as an evaluation of dynamic balance. Thirty-four children participated, 17 with CP (10 hemiplegia and 7 diplegia, mean age 10 years) and 17 TD (mean age 10 years 1 month). Three-dimensional kinematic and kinetic data of the lower limbs and trunk were captured during walking over level and uneven ground using Codamotion®. Statistical analysis was performed using a mixed-effects model two-factor Analysis of Variance (Group×Surface). Over both surfaces, children with CP showed increased trunk movement in the sagittal (Group effect, p<0.001) and transverse planes (p<0.001), and increased pelvic movement in the coronal plane (p=0.008), indicating impaired trunk control. Peak separation between the centre of mass and centre of pressure was reduced in CP, indicating impaired dynamic balance (p=0.027). TD children made a number of significant adaptations to uneven ground, including reduced hip extension (mean difference 3.4°, 95% CI [-5.3, -1.0] p=0.006), and reduced ankle movement in the sagittal (5.2°, 95% CI [0.01, 10] p=0.049) and coronal planes (2.4°, 95% CI [0.3, 4.5], p=0.029), but these adaptations were not measured in CP. A significant Group×Surface interaction was detected for knee sagittal range (p=0.009). The findings indicate that children with CP walk show impaired control of trunk movement and are less able to adapt their gait to uneven ground, particularly at the ankle.

Malone A ，Kiernan D ，French H ，Saunders V ，O'Brien T ... -  《-》

The influence of hip abductor weakness on frontal plane motion of the trunk and pelvis in patients with cerebral palsy.

Trendelenburg walking pattern is a common finding in various disorders, including cerebral palsy (CP), where it is seen in children and adults. Clinically, this deviation is viewed as a consequence of hip abductor weakness resulting in pelvic obliquity. Trunk lean to the ipsilateral side is a common compensatory mechanism to counteract pelvic obliquity and to maintain gait stability. However, no published investigations objectively address pelvic and trunk motions in the frontal plane or examine the correlation with hip abductor weakness in patients with CP. We selected 375 ambulatory (GMFCS I-III) patients with spastic bilateral CP and 24 healthy controls from our gait laboratory database. They had all undergone a standardized three-dimensional analysis of gait, including trunk motion, and a clinical examination including hip abductor strength testing. Selected frontal plane kinematic and kinetic parameters were investigated and statistically tested for correlation (Spearman rank) with hip abductor strength. Only a weak (r=0.278) yet highly significant correlation between trunk lean and hip abductor strength was found. Hip abductor weakness was accompanied by decreased hip abduction moment. However, no significant differences in pelvic position were found between the different strength groups, indicating that the pelvis remained stable regardless of the patients' strength. Our findings indicate that weak hip abductors in patients with CP are accompanied by increased trunk lean to the ipsilateral side while pelvic position is preserved by this compensatory mechanism. However, since this correlation is weak, other factors influencing lateral trunk lean should be considered. In patients with severe weakness of the hip abductors compensatory trunk lean is no longer fully able to stabilize the pelvis, and frontal pelvic kinematics differs from normal during loading response. The results indicate that the stable pelvic position seems to be of greater importance than trunk position for patients with CP. Further studies are needed to investigate other factors influencing lateral trunk lean.

Krautwurst BK ，Wolf SI ，Heitzmann DW ，Gantz S ，Braatz F ，Dreher T ... -  《-》

Pathological Movements of the Pelvis and Trunk During Gait in Children With Cerebral Palsy: A Cross-Sectional Study With 3-Dimensional Kinematics and Lower Lumbar Spinal Loading.

Increased loading at the lumbar spine, particularly in the coronal plane, has been reported in children with cerebral palsy (CP). As pelvic and trunk movements associated with Trendelenburg and Duchenne type gait are most significant in the coronal plane, the potential exists for lower lumbar spinal loading to be negatively affected in children with CP and these types of movement patterns. The objective of this study was to assess trunk and pelvic kinematics and lower lumbar spinal loading patterns in children with CP and Trendelenburg and Duchenne type gait. This was a cross-sectional study. Three-dimensional kinematic (lower limb and thorax) and L5-S1 kinetic data were recorded. Children were divided according to clinical presentation of Trendelenburg or Duchenne type gait. Several discrete kinematic and kinetic parameters were assessed between groups. Three distinct pelvic and trunk movement patterns were identified for children with CP: Trendelenburg, Duchenne, and complex Trendelenburg-Duchenne. Peak L5-S1 lateral bending moments were increased by 62% in children with CP and Duchenne type gait. Children with CP and complex Trendelenburg-Duchenne gait demonstrated the largest deviations from normal, with increased peak ipsilateral and contralateral directed moments of 69% and 54%, respectively, compared with children with typical development. A test-retest reliability analysis or measure of minimal detectable change was not conducted as part of this study. Results suggest that measures of minimal detectable change may be high for some of the reported variables. In addition, the inverse dynamic approach determines only the net intersegmental reactive forces that reflect the effect of external loads. Previous studies have shown that spinal loads may be larger than the net intersegmental force. Trendelenburg and Duchenne type movements were not always distinct, and a third type of movement, a combination of the two, was the most common in this study. Clinicians should be aware that children with CP and the Duchenne type or the complex Trendelenburg-Duchenne type of gait pattern experience abnormal loading that may have significant implications for the lower spine in the long term.

Kiernan D ，O'Sullivan R ，Malone A ，O'Brien T ，Simms CK ... -  《-》

How do children with bilateral spastic cerebral palsy manage walking on inclines?

Walking on inclined surfaces is an everyday task, which challenges stability and propulsion even in healthy adults. Children with cerebral palsy adapt similarly to inclines like healthy children do. However, how stability and propulsion in these subjects are influenced by different inclines remained unaddressed as of yet. The aim was to examine the feeling of safety, stability and propulsion of children with cerebral palsy when walking on inclines to gain insight into the challenges they might face on these conditions. Eighteen children with bilateral spastic cerebral palsy with gross motor function classification scale level I and II and nineteen healthy children underwent instrumented 3D gait analysis on level ground and on a 5° and a 10° incline. A mixed linear model was used to draw between and within group comparisons. Reduced lateral trunk sway, a relative lengthening of the lower limb at initial contact and a controlled walking speed were employed during downhill gait compared to level walking. Patients showed an increased sagittal ROM of trunk (3-4°) and pelvis (2-3°) and a decreased sagittal knee ROM (13°) compared to the typically developed children. During uphill gait, an insufficient increase of push-off power at the ankle (increase by 0.48 W/kg) was noted in children with CP, which appeared to lead to particularly shorter strides (about 0.1 m) in patients compared to healthy children (increase by 1.32 W/kg). Depending on inclination angle, children with cerebral palsy managed to walk on inclines in a controlled manner. The steeper the incline, the more the gait appeared to be affected: decreased feeling of safety, increased need for stabilising mechanisms for downhill gait and less sufficient uphill propulsion were seen. Helping these patients to attain better control during downhill gait and strengthening uphill gait mechanisms may support their participation in everyday life.

Yılmaz Topçuoğlu MS ，Krautwurst BK ，Klotz M ，Dreher T ，Wolf SI ... -  《-》