Reducing spasticity and enhancing postural control for the creation of a functional sitting position in children with cerebral palsy: A pilot study

The International Classification of Functioning, Disability and Health provides a Model for Adaptive Seating Interventions for Children with Cerebral Palsy

Children with severe types of cerebral palsy use adaptive seating systems to encourage function and assist in delaying the development of deformity. These systems are often assessed for and provided by occupational therapists. However, there has been no unifying policy or theoretical basis on which these systems are provided and research evidence is lacking, with studies tending to be small and non-controlled.

The International Classification of Functioning, Disability and Health (World Health Organisation 2001a,b) aims to establish a common language for clinical practice as well as research, while bringing together the opposing social and medical models of health care delivery. This paper suggests that the ICF model is an ideal theoretical basis for adaptive seating system assessment and provision, given that these systems often conflict between the medical model of reducing or delaying impairment of body functions and structures and the social model of children and families accessing life and environmental situations through mobility and seating equipment.

The paper considers all the domains of the ICF with regard to the current literature. It concludes that using the model in the context of providing adaptive seating gives occupational therapists both a powerful tool for communicating with children and families as well as managers and a basis for evaluating practice.

The effect of lower body stabilization and different writing tools on writing biomechanics in children with cerebral palsy

A high percentage of children with cerebral palsy (CP) have difficulty keeping up with the handwriting demands at school. Previous studies have addressed the effects of proper sitting and writing tool on writing performance, but less on body biomechanics. The aim of this study was to investigate the influence of lower body stabilization and pencil design on body biomechanics in children with CP. Fourteen children (12.31±4.13 years old) with CP were recruited for this study. A crossover repeated measures design was employed, with two independent variables: lower body stabilization (with/without) and pencil (regular/assigned grip height/biaxial). The writing task was to trace the Archimedean spiral mazes. Electromyography (EMG) of the upper extremity, the wrist flexion/extension movements, and the whole body photography were recorded to quantify the changes in posture and upper extremity biomechanics. Two-way repeated measures ANOVA was used for statistical analysis. No significant main effects were revealed in the EMG and wrist kinematics. The lower body stabilization significantly decreased the trunk lateral and forward deviations, and the visual focus-vertical angle. The biaxial pencil and the assigned grip height design significantly decreased the head, shoulder, trunk, and pelvic deviations compared with the regular design. The results indicated that the lower body positioning was effective in improving the trunk posture. A pencil with an assigned grip height or with a biaxial design could improve head, shoulder, trunk and pelvic alignment, but did not influence the muscle exertion of the upper extremity. This study could provide guidelines for parents, teachers and clinicians regarding the selection of writing tools and the knowledge of proper positioning for the children with handwriting difficulties. Further analyses can focus on the design, modification and clinical application of assitive sitting and writing devices for the use in children with handwriting difficulties.

Longitudinal study evaluating a seating system using a sacral pad and kneeblock for children with cerebral palsy

PURPOSE

Adaptive seating systems using sacral pads and kneeblocks are commonly used throughout the UK with children with complex motor disorders to improve their posture and stability in sitting. We sought to evaluate how effective these systems are for a group of children with cerebral palsy.

METHOD

A six-visit trial was performed to examine whether this combination controls pelvic and hip positioning. Twenty-three children with cerebral palsy aged 7 - 14 years participated (11 females and 12 males). The kneeblocks (active intervention) were removed for a period in the middle of the trial. Force exerted through the kneeblock, pressure exerted on the sacral pad and postural alignment was measured for change.

RESULTS

Statistically significant differences before and after kneeblock removal were found for force at the kneeblock, but no difference was found in pressure at the sacral pad. No statistically significant correlations between force and pressure or posture were found.

CONCLUSION

The results indicate that seating systems using a sacral pad and kneeblock may not improve overall posture but may improve hip position in children with cerebral palsy.

Effectiveness of adaptive seating on sitting posture and postural control in children with cerebral palsy

PURPOSE

We reviewed research on the effect of adaptive seating on sitting posture/postural control in children with cerebral palsy. Second, we examined whether changes in postural control related to changes in other aspects of functioning.

METHODS

Electronic database/hand searches were undertaken to locate studies published in English. Reviewers screened studies for inclusion criteria, extracted data, indexed outcomes to the International Classification of Functioning, Disability and Health, assigned levels of evidence, and assessed study quality.

RESULTS

Thirteen of 14 articles used group designs and the other a single-subject design. Conflicting findings were reported for saddle seats and optimal seat/back angle for improving sitting posture/postural control. Significant improvements were reported with seat inserts, external supports, and modular seating systems. Evidence supporting effects of postural control on functional abilities was limited.

CONCLUSIONS

Future studies on the effects of adaptive seating should describe participants with standardized classification systems and employ stronger research designs.

The effects of the saddle seat on seated postural control and upper-extremity movement in children with cerebral palsy

A repeated-measures experimental cross-over study was conducted with school-aged children with spastic cerebral palsy (spastic CP) to compare the effects of flat-bench versus saddle-bench seating on postural control and reaching motions. The saddle bench allowed significantly better postural control as measured by the clinical rating scale Sitting Assessment for Children with Neuromotor Dysfunction and by a study-defined variable, Spinal Extension. No statistically significant differences were found for any other variables using aggregate data-analysis techniques. However, the group results and those of single-subject data analysis suggest that the saddle seat may help such children to develop and maintain seated postural control and upper-extremity movement patterns.

Five-year follow-up of functional sitting position in children with cerebral palsy

Ten children with cerebral palsy (CP) were videotaped and photographed after the introduction to a functional sitting position (FSP--defined as a position in which children with CP could gain head-, trunk- and foot-control and the maximum degree of independent function when performing arm and hand movements during tasks) and again five years later. Head-, trunk- and foot-control, and arm- and hand-function were assessed from video-tapes by the Sitting Assessment Scale. The eight children who had been using the FSP throughout this period showed slight but significant improvement; the remaining two had deteriorated. Since all 10 children had undergone similar rehabilitation programmes, it is concluded that sitting in an FSP contributed to their improvement in the ability to use the hand and arm.

Development and preliminary validation of an instrument to assess quality of sitting of children with neuromotor dysfunction

The development of a clinical instrument to assess static and dynamic postural control in sitting in children with neuromotor dysfunction is described. A review of the literature has supported the need for objective assessment tools for measuring various aspects of functioning with this population. In this paper the conceptual basis and preliminary validation study results of a new instrument, the Sitting Assessment for Children with Neuromotor Dysfunction (SACND) are presented. Initial results show the SACND to have good inter-rater reliability, and discriminant validity. Construct validity testing suggest the SACND shows promise for use by clinicians and researchers. Further research is needed to assess the SACND's test-retest reliability, the major underlying test constructs, and the effects of intervention on test scores.

Influence of different sitting positions and abduction orthoses on leg muscle activity in children with cerebral palsy

A surface electromyogram (EMG) was recorded from four leg muscles to measure the effects of various seat inclinations and an abduction orthosis on eight children with cerebral palsy and controls during performance of an upper-extremity task and while listening to a story. EMG responses were lowest in the forward-leaning and horizontal positions with the abduction orthosis, and highest in reclined and horizontal positions without the orthosis for both groups of children during the performance of an upper-extremity task. While listening to a story, there was no median EMG activity in any muscles of the controls, but there were wide variations in those of the children with cerebral palsy. The results indicate that the use of an abduction orthosis and horizontal and forward-leaning seats decrease lower-extremity muscle activity, and so it is possible that it might also improve upper-extremity function.

Reviewing Muscle Cocontraction

From a purely mechanical standpoint, muscle cocontraction is an inefficient utilization of muscle forces. Muscles resist each other producing little, if any, net movement. In mature gait and posture, as well as in many skilled motor activities, reciprocal activation or inhibition commonly occurs. Muscle cocontraction is frequently seen in infants and toddlers, in persons with central nervous system (CNS) damage, and interestingly, it is also seen in normal adults when they are attempting a novel complex motor skill. How might these three situations be related? This article summarizes the developmental trend of decreasing cocontraction with age. The relationship of cocontraction to motor skill development is described. Finally, the role of co contraction in movement disorders of persons with CNS deficits is explored, and an attempt is made to synthesize the presented material.

Effects of seat-surface inclination on postural stability and function of the upper extremities of children with cerebral palsy

This study investigated the effects of seat-surface inclination on parameters of postural stability and functional use of the upper extremity. 10 non-impaired children and 10 children with cerebral palsy, aged between four and 15 years, were studied. Seat-surface inclinations of 0 degree, 5 degrees anteriorly and 5 degrees posteriorly were used as the experimental conditions. Significant differences were observed on most dependent measures between the two groups. The results suggest that anteriorly tilting the seats of children with cerebral palsy may disturb postural stability, without improving performance of the upper extremity.

Improvement of functional sitting position for children with cerebral palsy

Twenty-three children with cerebral palsy were photographed and video-filmed in six different sitting positions--including a hypothetical functional position--and the video-films and photographs were analysed. It was found that pathological movements were minimised and postural control and arm and hand function best when the child was sitting in a forward-tipped seat, with a firm backrest supporting the pelvis, arms supported against a table and feet permitted to move backward.