Head stability during quiet sitting in children with cerebral palsy: effect of vision and trunk support

Abstract

Deficits in postural control are one of the hallmarks of disability in children with cerebral palsy. Yet, much remains unknown regarding the etiology of postural deficits in these children. Here we evaluated postural control at a simplified task level by measuring head stability during quiet sitting while systematically manipulating the level of trunk support and vision in 15 children with CP (6-16 years), 26 typically developing (TD) children (4-14 years), and 11 adults. While TD children did not differ significantly from adults, children with CP had greater head movement than adults in both the sagittal and frontal planes under all conditions except frontal plane movement with Torso Support. Vision did not affect head stability in the sagittal plane for any group while it had differential effects on head stability in the frontal plane. Lack of vision improved head stability in adults and older TD children while destabilizing the head in young children (TD and CP) during the most unstable sitting position. Moreover, vision affected children with CP differently depending on their movement disorder. Children with spastic CP performed worse with eyes closed while those with dyskinetic CP had improved head stability with eyes closed. Our results demonstrate that children with mild to moderate CP have deficits in head stability even during quiet sitting. Keywords posture control; developmentDeficits in postural control are one of the hallmarks of disability in children with cerebral palsy (CP) (Bax, 2005, Rosenbaum et al 2002. One of the primary goals of postural control is to stabilize the head in space (Pozzo et al 1990, Prince et al. 1994, Assaiante & Amblard 1995. The sensory organs for visual and vestibular systems are embedded in the head, making refined head control of critical importance for both orientation and balance. (Liao et al. 2003b). Studies examining sitting control during surface perturbations have shown that children with spastic CP have increased frequency of antagonist activation, increased number of muscles recruited and a tendency for rostral to caudal muscle recruitment (Brogren et al 1996(Brogren et al , 2001). These researchers have suggested that "top down" recruitment of postural muscles may be a strategy used by children with CP to ensure stabilization of the head in space. Taken together these studies indicate that children with CP are unable to adequately stabilize their head in space during dynamic tasks and this may be related to immature or abnormal patterns of trunk muscle activation.It is unknown whether head instability in children with CP is related to coordination for dynamic tasks such as reaching or if there is an underlying deficit of postural control that constrains head stability even during quiet sitting. To our knowledge no studies have examined postural constraints in regards to head stability in children with CP. Therefore we have undertaken an evaluation of the contributions of trunk control and vision to head stability during quiet sitting in children with C...

The effects of different physiotherapy interventions on the activities of daily living and the quality of life in children with cerebral palsy

“…Gövde kaslarının en önemli görevi omurgada stabilizasyon sağlamak-tır. Bu stabilizasyon çocuğun bağımsızlığında, baş ve ekstremitelerin selektif hareketlerinde oldukça önemlidir (14)(15)(16)(17).…”

Postural Control Influence on Upper Extremity Function among Children with Cerebral Palsy: A Literature Review

“…The onset of reaching occurs after head and upper extremity control (Ju et al 2010). In order to achieve a stabilized head, good postural control is needed (Saavedra et al 2010).…”

“…Compared to the TD children, the spastic and ataxia types of CP rely totally on somatosensory information for postural control (Brogren et al 2001;Reilly 2005) and experience instability when only vestibular information is available (Reilly 2005;Saavedra et al 2010). The second level of adaptation of the direction-specific adjustments is based on the multisensory afferent input from somatosensory, visual, and vestibular systems (Hadders-Algra 2013).…”

“…The skill of a stabilized head may be achieved through practice of new experience involving balance problem (Saavedra et al 2010) and from trial and error (Hadders-Algra 2005). CWCP head instability while performing dynamic tasks is due to trunk muscle activation in abnormal patterns (Saavedra et al 2010). …”

“…Besides that, changing sensory environment also contributes to the postural stability (Reilly 2005) and CWCP have deficits of the sensory system (Saavedra et al 2010). Compared to the TD children, the spastic and ataxia types of CP rely totally on somatosensory information for postural control (Brogren et al 2001;Reilly 2005) and experience instability when only vestibular information is available (Reilly 2005;Saavedra et al 2010).…”