Motor control of the lower extremity musculature in children with cerebral palsy

The aim of this investigation was to quantify the differences in torque steadiness and variability of the muscular control in children with cerebral palsy (CP) and typically developing (TD) children. Fifteen children with CP (age=14.2±0.7 years) that had a Gross Motor Function Classification System (GMFCS) score of I-III and 15 age and gender matched TD children (age=14.1±0.7 years) participated in this investigation. The participants performed submaximal steady-state isometric contractions with the ankle, knee, and hip while surface electromyography (sEMG) was recorded. An isokinetic dynamometer was used to measure the steady-state isometric torques while the participants matched a target torque of 20% of the subject's maximum voluntary torque value. The coefficient of variation was used to assess the amount of variability in the steady-state torque, while approximate entropy was used to assess the regularity of the steady-state torque over time. Lastly, the distribution of the power spectrum of the respective sEMG was evaluated. The results of this investigation were: 1) children with CP had a greater amount of variability in their torque steadiness at the ankle than TD children, 2) children with CP had a greater amount of variability at the ankle joint than at the knee and hip joint, 3) the children with CP had a more regular steady-state torque pattern than TD children for all the joints, 4) the ankle sEMG of children with CP was composed of higher harmonics than that of the TD children.

Effects of a supported speed treadmill training exercise program on impairment and function for children with cerebral palsy

AIM

To compare the effects of a supported speed treadmill training exercise program (SSTTEP) with exercise on spasticity, strength, motor control, gait spatiotemporal parameters, gross motor skills, and physical function.

METHOD

Twenty-six children (14 males, 12 females; mean age 9y 6mo, SD 2y 2mo) with spastic cerebral palsy (CP; diplegia, n=12; triplegia, n=2; quadriplegia n=12; Gross Motor Function Classification System levels II-IV) were randomly assigned to the SSTTEP or exercise (strengthening) group. After a twice daily, 2-week induction, children continued the intervention at home 5 days a week for 10 weeks. Data collected at baseline, after 12-weeks' intervention, and 4 weeks after the intervention stopped included spasticity, motor control, and strength; gait spatiotemporal parameters; Gross Motor Function Measure (GMFM); and Pediatric Outcomes Data Collection Instrument (PODCI).

RESULTS

Gait speed, cadence, and PODCI global scores improved, with no difference between groups. No significant changes were seen in spasticity, strength, motor control, GMFM scores, or PODCI transfers and mobility. Post-hoc testing showed that gains in gait speed and PODCI global scores were maintained in the SSTTEP group after withdrawal of the intervention.

INTERPRETATION

Although our hypothesis that the SSTTEP group would have better outcomes was not supported, results are encouraging as children in both groups showed changes in function and gait. Only the SSTTEP group maintained gains after withdrawal of intervention.

Predicting functional change from preintervention measures in selective dorsal rhizotomy

OBJECT

In this investigation the authors attempted to predict change in function following selective dorsal rhizotomy (SDR) and intensive physical therapy in patients with spastic diplegic cerebral palsy (CP) based on multidomain preintervention measures.

METHODS

Data pertaining to 22 children with CP were collected before the SDR and again 20 months afterward. Although equations for predicting change in gait speed and function (such as the Gross Motor Function Measure) were derived, the 95% confidence interval (CI) widths were too broad to make accurate predictions that were clinically useful outside the study group.

CONCLUSIONS

Future work should be focused on developing additional measures such as lower-extremity motor control and balance in an attempt to reduce the CIs to more clinically relevant values.

Rehabilitation management of Friedreich ataxia: lower extremity force-control variability and gait performance

We describe the rehabilitation management during a 12-month period of a 14-year-old female with Friedreich ataxia. Interventions included task-oriented bimanual reaching activities, functional strengthening, and gait training using a walker featuring tension-controlled wheels and a reverse-braking system. Her physical status was assessed with the Nine-Hole Peg Test, single limb stance time, manual muscle testing, self-reported falls, isometric force control testing, and 3-dimensional gait analysis in a motion-capture laboratory. Although measures of the patient's Nine-Hole Peg Test, single limb stance time, and manual muscle testing reflected minimal changes, her gait speed decreased by 69.4%. However, the force-control targeting of her dominant knee extensors showed a 43.7% increase in force variability that was concomitant with her decline in gait performance. The decrement of her initial gait speed was reduced to 42.9% on replacing the wheeled walker with the U-Step Walking Stabilizer at the end of the intervention period. Although the patient's gait remained significantly impaired, extended use of the U-Step Walking Stabilizer modestly improved her gait performance, and her rate of falls decreased from 10 to 3 per month. Our observations suggest that use of force-control testing as proxy measures of ataxia and tension-controlled gait aids show promise in the management of Friedreich ataxia and merit further investigation.

Quantifying Active Ankle Range of Motion in Cerebral Palsy Following Selective Dorsal Rhizotomy

This study was conducted to determine whether an objective and quantitative measure for active ankle range of motion would be sensitive to differences between persons of able body and those with cerebral palsy (CP), and between pre- and postselective dorsal rhizotomy (SDR). Twelve children with spastic diplegia CP were tested before undergoing an SDR, and again after 8 months of intensive physical therapy (SDR group). Fourteen other children with spastic diplegia were tested initially and again 8 months following no intervention but maintaining their existing level of physical therapy (CP group). Twenty age-matched children of able body were tested once (AB group). A video system recorded active sagittal plane ankle movements as the seated child independently performed maximum dorsiflexion and plantarflexion. The data were tracked and analyzed to determine end-range dorsiflexion and plantarflexion, and total active ankle range of motion. Repeated-measures ANOVA and Tukey post hoc tests were used to test for significant differences among and between groups, p < 0. 05. Results for the SDR group indicated a significant increase in end-range dorsiflexion and total range of motion following the surgery, with no changes in any measures for the CP group. Results for both groups with CP indicated differences vs. the AB group. The measure provided additional information from what has previously been reported for active ankle range of motion. The integration of this measure with other objective measures for quantifying impairments and presurgical function may be useful in predicting post-SDR gait status and other functional activities.