Dynamic Surface Exercise Training in Improving Trunk Control and Gross Motor Functions among Children with Quadriplegic Cerebral Palsy: A Single Center, Randomized Controlled Trial.

BACKGROUND: Dynamic surface provides proprioceptive and vestibular feedback with optimal level of arousal. The activities on unstable environment have greater sensorimotor experiences. There is a lack of evidence examining the benefits of dynamic surface exercise training (DSET) among the children with spastic quadriplegic cerebral palsy (CP). AIM: The aim of the study was to analyze the effect of dynamic surface exercises on trunk control and gross motor functions in children with quadriplegic CP.
MATERIALS AND METHODS: A total of 30 children with spastic quadriplegic CP with Gross Motor Function Classification System of levels III and IV were recruited by the simple random sampling method (random number generator) to participate in this randomized controlled study. Recruited children were randomly divided into two groups, DSET group and standard physiotherapy training group. Both the groups received active training program lasting for 60 min, 4 days/week for 6 weeks. Gross Motor Function Measure (GMFM)-88 and Pediatric Balance Scale (PBS) scores were recorded at baseline, and at the end of 6-week post-intervention.
RESULTS: Total 30 children with quadriplegic CP with mean age 6.64 ± 2.15 years in experimental group and 6.50 ±1.59 years in control group participated in the study. Experimental group showed a significant difference for GMFM and PBS scores between pre- and post-intervention with P < 0.005. A significant difference was observed in GMFM scores between experimental and control group with P < 0.005.
CONCLUSION: Six-week dynamic surface exercise therapy along with standard physiotherapy was effective in improving trunk control and gross motor function performance among children with spastic quadriplegic CP aged 6-12 years. Copyright:

INTRODUCTION

Cerebral palsy (CP) is a well-documented nonprogressive neurodevelopmental condition commencing in early childhood and persisting throughout life.[1] CP is the leading cause of chronic disability in children, making them physically and mentally handicapped and socially unapproachable.[2] The worldwide incidence of CP is approximately 2–2.5 cases per 1000 live births. In India, it is estimated at around three cases per 1000 live births. There are approximately 25 lakh children with CP in India as per the last statistical information. A study conducted in Jalandhar District of Punjab reported the prevalence of quadriplegic CP accounting for 10%–15% in 1000 cases of CP from India with complex motor skill disorders.[3]

The neuromuscular deficits observed in children with CP include abnormal muscle tone that affects posture, movement, alteration of balance and motor coordination, decrease in strength, and loss of selective motor control, leading to functional limitation.[4] Most children with CP have difficulty in walking, show poor balance control that leads to poor gait. Therapies tend to address the impairments in body structure and function (i.e., spasticity, decreased strength, and range of motion) associated with CP. Interventions for these impairments, such as physical therapy or injections and orthopedic and neurological surgeries, may have the desired goal of improving walking activity, and overall health related quality of life.

Neurodevelopmental principles state that the control of movement proceeds from the proximal to the distal part of the body. The trunk being the central key point of the body, proximal trunk control is a prerequisite for distal limb movement control, balance, and functional mobility. Using dynamic surface for exercise provides proprioceptive and vestibular feedback about the position of their body segments in space with adaptive motor control response to stimuli. The activities on unstable environment with feedback system can have greater sensorimotor experiences.[56] It is proven that trunk muscle exercises performed on a physio ball lead to better trunk muscle activity in healthy individuals. Dynamic surface will maintain the arousal level at optimal in three-dimensional plane. The potential activation of musculature is better when the exercises are performed on unstable surface rather than when they are performed on a plinth. Since, the movement of a surface beneath the participants provides a postural perturbation to which the muscles respond in order to maintain the desired posture will be greater.[789]

Standard physiotherapy based on motor-learning principle is task-specific training, which involves practice of functional movements in activities of daily living. Previous literatures have shown that the practice of task-specific activities results in an optimal improvement in functional movement in children with CP. Rehabilitation outcomes are more successful when the tasks are of greater functional reorganization. Repetition and consistency in practice play important roles in inducing reorganization of cortical maps and maintaining long-lasting cortical changes acquired in task-specific therapy.[101112] But, there is a lack of evidence, which examines the benefits of dynamic surface exercise training (DSET) among the children with spastic quadriplegic CP.

MATERIALS AND METHODS

Ethical statement and recruitment

By screening 60 children with spastic quadriplegic CP, 30 children, aged between 5 and 12 years, including both male and female were recruited for the two-group randomized single centre clinical trial by simple random sampling technique. The study was conducted in tertiary care teaching hospital and recognized center for special children. Children with spastic diplegic CP who were able to follow verbal commands and who were having level III and IV of Gross Motor Function Classification System (GMFCS) were included in the study. Children who were uncooperative, having visual or intellectual impairments, on antiepileptic and antispasticity medications, with hearing deficit, any cardiac anomalies affecting exercise tolerance, and less than 4 months after undergoing orthopedic surgery or botulinum toxin injections were excluded from the study. After obtaining ethical approval from the recognized hospital ethics committee, Mohali, India, the study protocol was uploaded in open access clinical trial registry platform, Clinical Trials Registry, India (http://ctri.nic.in/) approved by the World Health Organization’s International Clinical Trials Registry Platform and International Committee of Medical Journal Editors. Written informed consent was obtained from the participants’ caregiver or parents before the commencement of the study.

Random allocation

Block randomization was used to allocate the children with spastic quadriplegic CP into DSET group and standard physiotherapy training (SPT) group. The method of allocation was concealed in sequentially numbered, sealed, opaque envelopes. Active training was provided for 6 weeks followed by 2-month follow-up without intervention. Before the beginning of the actual intervention, the anthropometric measures, such as age, height, and weight, were recorded. The blueprint of study plan is displayed in Figure 1 as consolidated standards of reporting trials (CONSORT) flowchart.

Figure 1

Consolidated standards of reporting trials (CONSORT) flowchart of the study

Intervention

DSET group

The DSET group followed a 6-week dynamic surface training for 60 min/day for 4 days/week. The details of DSET given to the children with spastic quadriplegic CP is shown in Table 1.

Table 1

Dynamic surface exercise therapy along with standard physiotherapy given to the children with quadriplegic CP

S. no.	Principles	Equipment	Activity	No. repetitions	Sets
1	Optimal arousal	Physio ball	Make the child bounce, active/passive on the Swiss ball, slow/fast	5 times	5 sets
2	Combined frontal and transverse plane movements	Physio ball/ bolster	High sitting: one hand weight bearing followed by trunk rotation to reach the toy on opposite side	5–7 each side	1 set
3	Combined frontal and transverse plane movements	Platform swing	Reaching the toy with both the hands kept overhead and 45°–60° diagonal to the mid line	5–7 times each side	1 set
4	Trunk activation activities	Physio ball/ bolster	High sitting foot placing on the ground: throwing the ball with both the hands.	5 times	1 set
			Roll the ball/bolster maximum backward and hold for 10s, keeping pelvis in neutral, knee in extension, foot in plantar flexion	5 times	1 set
5	Dynamic trunk activities in sitting (transverse and frontal plane)	Physio ball/ bolster	High sitting foot placing on the ground	5 times each side	1 set
			Reaching the toy sideways with one hand by shifting the body weight toward the reaching side Reaching the toy with both the hands kept little back with trunk rotation toward the reaching side	5 times each side	1 set

SPT group

Children with spastic quadriplegic CP in SPT group followed a 6-week dynamic surface training for 60 min/day for 4 days/week. The details of SPT given to the children with spastic quadriplegic CP is present in Table 2.

Table 2

Standard physiotherapy provided to the children with quadriplegic cerebral palsy

S. no.	Equipment	Activity	Repetitions	Sets
1	Floor mat	Side sitting to quadriped–quadriped to side sit (transition activity)	5 times each side	1 set
2	On bench/stool	Sitting and reaching	5 times each side	1 set
		Side ways
		Overhead
3	On floor	Standing: throwing and catching the ball from different direction	10 times each side	1 set
4	On bench/stool	Forward bend and pick the ball come back to sitting and through the ball	10 times	1 set
5	On mat	Long sitting reaching for a toy sideways both the sides	10 times each side	1 set

Outcome measures

Gross Motor Function Measure (GMFM) and Pediatric Balance Scale (PBS) were the outcome measures used in this trial. GMFM-88 has excellent relative reliability of excellent (Intraclass correlation coefficient (ICC) = 0.952–1.000). The responsiveness of the GMFM-88 is reasonable for measuring gross motor function in children with CP.[13] According to the scoring sheet, activities were scored as 0, 1, 2, 3, and not tested by observing the child’s performance with higher rating representing better performance. PBS has extremely high intra-rater reliability with ICC = 0.99 and its inter-rater reliability is ICC = 0.99.[14] GMFM-88 and PBS were recorded at baseline and at the end of 6-week post-intervention.

Data analysis

The collected demographic and outcome measures were assessed for their normality using Shapiro–Wilk test. As the demographic data follow normal distribution, all the descriptive statistics were expressed in mean ± standard deviation (SD). The outcome measures, GMFM-88 and PBS score, follow normal distribution. Hence, they were expressed in mean and ± SD. Paired t test was adopted to find the differences between baseline and after 6-week intervention in DSET group and SPT group in the outcome measure. The data were analyzed using statistical software, Statistical Package for the Social Sciences (SPSS), version 20.0 (IBM SPSS, Armonk, New York). The P value ≤ 0.05 was considered to be statistically significant.

RESULTS

Thirty children with spastic quadriplegic CP were recruited for the study. Among them, 15 were randomly allocated into DSET group and remaining 15 to SPT group. The demographic characteristics of the recruited children with spastic quadriplegic CP are present in Table 3. Within the group comparisons at baseline and at the end of 6-week training, intervention for the outcome measures, GMFM-88 and PBS, is present in Table 4 and Table 5, respectively.

Table 3

Baseline demographic characteristics of the children with quadriplegic CP recruited

Demographic dimensions		DSET group (n = 15)	SPT group (n = 15)
Age (years)		6.64 ± 2.2	6.50 ±1.6
Gender	Male	09	09
	Female	06	06
GMFCS	Level 3	10	08
	Level 4	05	07

Table 4

Baseline and post 6-week intervention changes in GMFM and PBS scores among the children with quadriplegic CP recruited in dynamic surface exercise therapy group

Outcome measures	Baseline Mean (SD)	Post 6-week intervention Mean (SD)	P value
GMFM	44.07 ± 17.16	58.19 ± 16.84	0.001
PBS	4.13 ± 1.06	5.13 ± 1.45	0.002

Table 5

Baseline and post 6-week intervention changes in GMFM and PBS scores among the children with quadriplegic CP recruited in SPT group

Outcome measures	Baseline Mean (SD)	Post 6-week intervention Mean (SD)	P value
GMFM	50.88 ± 16.58	53.11 ± 17.56	0.005
PBS	4.13 ± 1.06	4.60 ± 1.12	0.008

DISCUSSION

The aim of this study was to analyze the effect of dynamic surface exercises along with standard physiotherapy (DSET group) and SPT alone (SPT group) on trunk control and gross motor functions in children with quadriplegic CP.

Results of this study showed a significant difference between pre- and posttreatment sessions for both GMFM and PBS within experimental group and control group. On comparing between the groups, the experimental group, which used dynamic surface along with standard physiotherapy, showed a significant improvement on GMFM scores when compared with control group, which received standard physiotherapy alone. However, the PBS scores were equal in both groups.

To the best of our knowledge, this is the first study evaluating the effect of dynamic surface exercises to improve trunk control and gross motor functions in children with quadriplegic CP. The treatment techniques incorporated in this study were based on motor learning theory. Standard physiotherapy based on task-specific interventions was incorporated in both the groups. The experimental group received additional dynamic surface exercise intervention. Furthermore, the advantage of the dynamic surface is that it provided a postural perturbation, which caused muscle activation to maintain a posture.

The brain plasticity and behavioral changes of children with CP are enhanced when they are given a task or treated with a therapeutic method that requires troubleshooting ability. In this study, we have taken scores of sitting, crawling and kneeling, and standing (GMFM Domains B, C and D) in GMFM-88 to analyze the trunk control in both the groups for pre-intervention and post-intervention. Hence, it was hypothesized that trunk control should impact the gross motor function.

The results of this study are similar with those of a study by Bae et al.[15] on changes in the cross-sectional area of the muscles with trunk stabilization exercise on different support surfaces in adult patients of stroke, which were examined using computed tomography. The study showed that exercise on the unstable support surface enhanced the size of the cross-sectional area of the trunk muscles and balance ability significantly more than exercise on the stable support.

Shin et al.[16] conducted a case series on trunk stability exercise in school-going children for 8 weeks, and the results indicated that neck and trunk stabilization exercises that require children’s active participation were helpful in improving static and dynamic balance ability among children diagnosed with CP.

Possible mechanisms of action of dynamic surface exercise on trunk control and gross motor function might be due to the following three components.[17] First, dynamic surface deliver feedback mechanisms that generate an appropriate corrective torque based on how the vestibular sensory cues detect deviations of head orientation from the vertical (gravity); second, the proprioceptors detect orientation relative to the support surface; and third, the visual sensors detect head orientation relative to the visual field.[17] In this way, visual receptors, proprioceptors, and mechanoreceptors are the direct route of input entry provided by dynamic surface.[17]

Karthikbabu et al.[7] reported similar results on adult patients with acute stroke and concluded that the group, which performed task-specific trunk exercises on an unstable surface, improved more significantly on trunk control and functional balance than the group that performed the exercises on a stable surface.

A number of studies have emphasized the requirement for rehabilitation methods that are both relevant to the patient’s real-world environment, and that can also be transferred to other daily living tasks.[15161718] In this study, greater improvement was observed in trunk control and gross motor function. Limitation of the study is that this study did not focus on the different types of CP and the age group of the children in this study was 6-12 years. Strength of the study was that to the best of our knowledge, there are no studies on quadriplegic CP to investigate the effect of DSET along with standard physiotherapy between the age 6 and 12 years on trunk control and gross motor function among children with spastic quadriplegic CP. As CP rehabilitation is a long-term process, this system provides a good alternative tool for evaluation and treatment planning.

CONCLUSION

Six-week study result showed that dynamic surface exercise therapy along with standard physiotherapy was effective in improving trunk control and gross motor function performance among children with spastic quadriplegic CP aged 6–12 years. DSET is a safe and sensory feedback-involved therapeutic program.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.