http://informahealthcare.com/dre ISSN 0963-8288 print/ISSN 1464-5165 online Disabil Rehabil, Early Online: 1–8 ! 2014 Informa UK Ltd. DOI: 10.3109/09638288.2014.972592
RESEARCH PAPER
Sit-to-stand movement changes in preschool-aged children with spastic diplegia following one neurodevelopmental treatment session – a pilot study Ryo Yonetsu1, Akira Iwata1, John Surya2, Kazunori Unase3, and Junichi Shimizu4 Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
1
Department of Physical Therapy, Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Osaka, Japan, 2Department of Physical Therapy, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan, 3Osaka Developmental Rehabilitation Center, Osaka, Japan, and 4Department of Occupational Therapy, Tokyo University of Technology, Tokyo, Japan
Abstract
Keywords
Purpose: This study was designed to provide a better understanding of how a single neurodevelopmental treatment (NDT) session affects sit-to-stand (STS) movements in children with cerebral palsy (CP). Methods: Eight children with spastic diplegia and five typically developing children, aged 4–6 years, participated in this study. The CP participants performed STS movements immediately before and after a 40-min NDT session. Using a three-dimensional, four-camera analysis system, angular movements involving the hip, knee and ankle joints of the participants were obtained. Results: During forward tilt of the trunk, the maximum and final angles after the NDT session significantly decreased compared with those before the session (p50.05, p50.01). Moreover, the final hip flexion after the session also significantly decreased compared with that before the session (p50.01). On the other hand, the initial, maximum and final ankle dorsiflexion angles after the session were significantly greater (p50.05, p50.01 and p50.05, respectively) than before the session. Conclusions: These findings suggest that a single NDT session enables children with CP to stand from a seated position without using some atypical movement patterns.
Motion analysis, neurodevelopmental treatment, sit-to-stand movement, spastic diplegia History Received 5 December 2013 Revised 19 September 2014 Accepted 30 September 2014 Published online 20 October 2014
ä Implications for Rehabilitation
Preschool-aged children with spastic diplegia, with limited ability to independently transfer from a sitting position, and dependent on a wheelchair for mobility experience obstacles to enhanced activities of daily life and social participation. A single neurodevelopmental treatment session would enable children with spastic diplegia to perform sit-to-stand movements more efficiently, with selective muscle control. Understanding how a single neurodevelopmental treatment session affects sit-to-stand movements in children with spastic diplegia is invaluable for therapists planning more efficient therapeutic programs and may enable children with spastic diplegia to develop improved mobility
Introduction The ability to stand after being seated in a chair, called the sit-tostand (STS) movement, is a fundamental activity for upright mobility and a prerequisite for many functional activities. Thus, STS movement is an important goal for improving mobility in children with cerebral palsy (CP). Recently, the five-repetition STS test that has good reliability and validity was introduced for the assessment of muscle weakness and its post-interventional clinical change as an outcome variable for children with CP [1,2]. However, assessments using this test are limited to children with CP in a prestanding status because many children with CP Address for correspondence: Ryo Yonetsu, 3-7-30 Habikino, Habikino, Osaka 583-8555, Japan. Tel: +81 72 950 2872. Fax: +81 72 950 2130. E-mail: [email protected]
demonstrate difficulty in independently accomplishing the STS movement. Particularly, early in life, children with CP manifest loss of selective muscle control, dependence on primitive reflex patterns, relative imbalance between muscle agonist and antagonist activities and deficient equilibrium reactions [3]. Therefore, STS movements in children with CP are characterised by various compensatory patterns [4–6]. Based on the International Classification System of Functioning Disability and Health framework [7], preschool-aged children with CP who are dependent on a wheelchair or assistive buggy for functional mobility have a limited ability to independently transfer from a sitting position, which becomes an obstacle to activities of daily life (ADL) and social participation. Neurodevelopmental treatment (NDT) is the predominant method for treating children with CP [2,8]. This approach focuses on establishing normal sensorimotor components such as muscle
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
2
R. Yonetsu et al.
tone and reflexes or on inhibiting atypical movement patterns to improve functional movements. This treatment outcome is achieved through physical support of the child during movement. As the child gains postural control, the therapist gradually withdraws support. In this way, one of the goals of NDT is to facilitate repeated, active movements involving postural control and functional goals [9]. Most studies on the effectiveness of NDT have found motor performance improvements, especially in gross motor ability [10–15]. Although few studies have demonstrated how NDT encourages normal movement patterns and diminishes atypical patterns during functional movements (reaching, standing and gait) in individuals with CP [16–18], a study focused on STS movements has not been reported. More information regarding how NDT affects STS movements would be advantageous for therapists designing and planning more efficient programs. A previous case study [6] attempted to assess the STS movement immediately before and after a single NDT session in a child with spastic diplegia CP who could not stand without assistance. The study found that after one NDT session, the subject could maintain ankle dorsiflexion from the initial to the final position, decrease forward tilt of the trunk when the subject’s hips lifted off the chair seat and lock the hip and knee joints in a linear extension pattern after the hips were off the seat during the STS movement. These findings led to the conclusion that after one NDT session, STS movements were more efficient. However, this conclusion was based on data from a single subject. Therefore, using a larger sample, this pilot study was designed to provide a better understanding of the effects of a single NDT session on the STS movements in preschool-aged children with CP who had a limited ability to transfer from sitting positions. The primary goal of this study was to asses STS movements before and after one NDT session in these children. The working hypothesis was that a single NDT session would enable these children to stand from a chair without using atypical movement patterns. Based on a previous case study [6], STS movements after single NDT sessions were hypothesised to have the following characteristics compared to those before the session: (i) diminished excessive trunk forward tilt, (ii) maintenance of ankle dorsiflexion and (iii) hip and knee joints locked in a linear pattern of extension. Thus, children with CP would be able to extend their body vertically without increasing their ankle plantarflexion while standing. The secondary goal was to understand how far STS movements, after one NDT session, moved towards normal in subjects with CP. These efforts would help children with CP enhance their ADL and social participation.
Methods Study design The aim of this pilot study was to provide a better understanding of the effects of one NDT session on STS movements in subjects with CP. A single-group, before-and-after design was employed. Children with CP received a single, 40-min physiotherapy session at their convenience. One session of regular NDT-based physiotherapy was regarded as a single NDT session. Each patient completed a pretest and posttest assessment immediately before and after their sessions. By assessing the STS movements in normally developing children, the extent to which STS movements moved towards normal after a single NDT session for CP patients was also investigated. Participants Participants were recruited from the Osaka (Japan) Developmental Rehabilitation Centre between March 2010 and December 2012. A convenience sampling of eight preschool-aged
Disabil Rehabil, Early Online: 1–8
Table 1. Participant profiles. Age Height Weight Participant (months) Gender (cm) (kg) 1 2 3 4 5 6 7 8
50 52 52 55 62 69 69 69
Boy Girl Boy Boy Boy Boy Girl Boy
97 86 87 85 91 93 98 102
13.7 10.2 13.5 12.6 11.2 15.9 12.6 15.8
Functional mobility Wheelchair Wheelchair Buggy Buggy Wheelchair or walker Wheelchair or walker Walker or wheelchair Wheelchair or walker
children with spastic diplegia CP (six boys, two girls), with limited ability to transfer from sitting positions, participated in this pilot study (Table 1). All participants had received regular NDT-based physiotherapy more than once a week (40 min per session) for the previous three months at this rehabilitation centre. The study’s inclusion criteria were as follows: (i) ability to independently maintain a sitting position on a bench and the ability to stand with the assistance of a grip bar; (ii) 4–6 years of age; (iii) grade 1 to grade 2 score according to the modified Ashworth scale [19]; (iv) absence of joint contracture and fixed deformities; (v) no previous remedial orthopaedic surgery or medication to reduce spasticity during the previous 6 months [1,2]; (vi) absence of visual or auditory problems; and (vii) ability to understand verbal commands. Consequently, all participants were classified as Gross Motor Function Classification System [20]. Level III; three children had undergone muscle release operations or received botulinum toxin type A (BTA) injections. In addition, five match-aged typically developing children (two boys, three girls; mean age, 61 years; SD 10 months) were included as normal controls. This research was conducted after the Osaka Prefecture University Research Ethics Committee (2009–06) had approved the study. The purpose of this study was explained to the participants’ parents both orally and in writing, and written consent was obtained. Intervention Three physiotherapists administered the interventions. Each therapist was certified in paediatric NDT and had more than 10 years’ experience [6]. Each CP participant received one, 40-min NDT session from one of the physiotherapists. Although the treatment activities varied for each CP participant, the overall goals (improved smoothness and efficiency of movement), which included improved trunk, hip, knee and ankle control during the STS movement, were the same for all CP participants. All sessions incorporated handling techniques that aimed to alter muscle tone during movement and to facilitate antigravity, weight-shifting and postural reactions [9]. Consequently, the standing position accounted for more than half of each participant’s total treatment. An adjustable-height desk with toys placed on it was prepared in front of each CP participant. The height of this desk was as high each CP participant’s sternal xiphoid process when the participant was standing. The support surface of this desk was 60 cm wide and 50 cm long. The toys that were selected were ones that could be held and manually manipulated by the child (e.g. cups, spoons and stones). The physiotherapist manipulated both knee joints of each CP participant to facilitate hip and knee extension (Figure 1A). Moreover, the physiotherapist facilitated weight-shifting and postural reactions during reaching actions (Figure 1B). If the CP participant could extend their hips and knees easily, the physiotherapist gradually decreased the degree of handling (Figure 1C). With this
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
STS movement changes in CP following NDT
3
Figure 1. Examples of the neurodevelopmental training approach for children with spastic diplegia cerebral palsy. (A) The physiotherapist manipulates both knee joints of the participant to facilitate hip and knee extension and postural reactions. (B) The physiotherapist facilitates weight-shifting and postural reactions during forward reaching actions (C) If the participant can extend their hips and knees easily, the physiotherapist gradually decreases the degree of handling.
type of support, each CP participant developed enhanced control of their posture and motion while playing [9]. Incidentally, since NDT focuses on enhancing body righting and equilibrium reactions [9], each physiotherapist was prohibited from intentionally duplicating STS movement, which may have affected the final outcome. Procedures In order to assess STS movements, a grip bar, a motion analysis system (Kinema Tracer, Kissei Comtec, Matsumoto, Japan) with four cameras (30 Hz), and a novel pressure-sensitive trigger device (100 Hz) were used. Two cameras were placed on each side of the child, perpendicular and oblique to their sagittal plane. The pressure-sensitive trigger device, which detected and recorded the loss of contact with the seat (when the participant’s weight was reduced by 53 kg), was placed on the bench and was synchronised with the four-camera motion analysis system. Markers were placed on both sides of the lateral aspect of each participant’s fifth metatarsal head, lateral malleolus, lateral femoral condyle, greater trochanter and acromion [6]. The STS movements were performed with each participant barefoot and their feet on the floor. Each participant used a bench, the height of which was adjusted to the leg length of each participant to allow positioning of the ankle, knee and hip joints as close to 90 as possible. Both feet were kept at shoulder-width apart on the floor, with the hands on the knees. A bar at the height of the seated participant’s shoulder joint was placed in front of the bench at a distance equal to the length of the upper extremity with the shoulder joint at 90 flexion. Each participant was asked to rise from the bench in his or her usual manner by using the grip bar. If a participant performed the STS movement with additional antics, such as rotating head or pulling the bar backwards and forwards in the standing posture, additional instructions were given. Instructions that might affect STS movement patterns, such as ‘‘Pull your feet’’, were not given [21,22]. Each participant executed the STS movements three times before and after the single NDT session; for analysis, the most symmetric movement among each of the three trials was selected [6]. Data analysis Data analysis was performed by another physiotherapist who did not administer the intervention. The initial point of the STS
motion (T1) was defined as the point at which each hand started to move, and the end point of the STS motion (T3) was defined as the point at which the motion of the trunk or knees stopped. The point at which the individual’s weight was off the buttocks (T2) was measured, based on data derived from the trigger device, and was defined as the point at which the electrical waveform was at its lowest voltage. In this way, the total duration of the STS movement and the durations of the other phases (phase I [T1 to T2], forward transfer to phase II [T2 to T3] and standing) of the STS movement from the three transitional points were also assessed. Angular movements involving the trunk and hips, the knees and the ankle joints of the participants (involving the 16 lower limbs) were collected. The angular movements of each joint are defined in Figure 2. Briefly, the angular movement of the trunk forward tilt (A) occurred between an imaginary line extending from the acromion to the greater trochanter and a vertical line extending through the greater trochanter. Similarly, angular hip movement (B) occurred between the line extended from the acromion to the greater trochanter and a line connecting the greater trochanter and the lateral femoral condyle. Angular knee movement (C) occurred between the line extended from the greater trochanter to the lateral femoral condyle and a line connecting the lateral femoral condyle and the lateral malleolus. Angular ankle movement (D) occurred between a vertical line extended from the lateral femoral condyle to the lateral malleolus and a line connecting the lateral malleolus and the lateral aspect of the fifth metatarsal head. In healthy young adults, the hip and knee joints extend and lock together in a linear pattern after a subject’s hips lift off the seat [23]. The angular movements of the hip and knee joints between T2 and T3 were converted to 100% to reveal the relationship between the hip and knee joints after the hips were lifted off the seat. In this manner, averaged kinematic curves were drawn to represent the relationship between the movements of these joints. In order to examine within-group differences, before and after the NDT session, descriptive statistics were generated for all demographic variables. Based on the output from the Shapiro– Wilk’s test, the angular movement data, except for hip flexion after NDT at T1 and T2, were normally distributed; therefore, parametric tests were used for the analysis. A paired t-test was conducted to examine within-group differences before and after
4
R. Yonetsu et al.
Disabil Rehabil, Early Online: 1–8
the NDT session. Wilcoxon’s signed rank-sum test was conducted for the assessment of hip flexion at T1 and T2 due to the nonnormal distribution of data. For the analysis of the duration of the STS time, Wilcoxon’s signed rank-sum test was used due to the small number of data. p Values50.05 were considered statistically significant.
Effect sizes were calculated to examine the magnitude of change and interpreted based on Cohen’s proposed conventional values for t-tests for means that are small ¼ 0.2, medium ¼ 0.5 and large ¼ 0.8 [24]. Data comparison between normal control and CP participants after the NDT session were not subject to a statistical analysis; these data were regarded as supplemental reference values.
Results
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
Total duration of the STS movement After the NDT session, seven of the eight CP participants showed a decreased total duration of the STS movements compared with that before the NDT session (Figure 3A). The average duration of the STS movements, after the NDT session was less than before the intervention (p50.05, d ¼ 0.73) (Table 2). Moreover, the duration of phase II decreased, for all CP participants, after the NDT session (p50.05, d ¼ 0.78) (Figure 3C and Table 2). The duration of STS movements in the children with CP lasted longer even after the NDT session than in the normal control children (Table 2). Angular movements of each joint
Figure 2. The definitions of angular movements of each joint (A, trunk; B, hip; C, knee; and D, ankle).
The averaged kinematic curves are shown in Figure 4 (A, trunk; B, hip; C, knee; and D, ankle joints, respectively). After the NDT session, the maximum and the final angles of the trunk’s forward tilt significantly decreased compared with those before the session (p50.05, d ¼ 0.49 and p50.01, d ¼ 0.88, respectively; Table 3). Although the maximum angle after the session was not different between the children with CP and the normal controls, the point of maximum angle occurred later than in the controls (Figure 4A). After the session, the final hip flexion angles were also significantly decreased compared with those before the session (p50.01, d ¼ 0.93; Table 3). However, the knee flexion angles, measured after the session, were not significantly
Figure 3. The duration of sit-to-stand movements before and after one neurodevelopmental treatment (A, total duration; B, phase I; and C, phase II) in children with spastic diplegia cerebral palsy. *p50.05.
Table 2. The duration of sit-to-stand movements. Spastic diplegia cerebral palsy (n ¼ 8)
Total duration (s) Phase I (s) Phase II (s)
Typically developing children (n ¼ 5)
Before NDT Mean (SD)
After NDT Mean (SD)
p
d
Mean (SD)
3.82 (1.69) 1.94 (0.73) 1.88 (1.02)
2.88 (0.71) 1.65 (0.22) 1.23 (0.59)
0.036 0.223 0.012
0.73 0.54 0.78
2.19 (0.59) 1.20 (0.59) 0.99 (0.34)
NDT, neurodevelopmental treatment and SD, standard deviation. Phase I, the time between T1 and T2 and Phase II, the time between T2 and T3. Cohen’s d: small 0.2; medium 0.5; and large 0.8.
STS movement changes in CP following NDT
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
5
Figure 4. The averaged curves of angular movement (A, trunk; B, hip; C, knee; and D, ankle joints) in typically-developing (dashed line) children and in children with spastic diplegia cerebral palsy before (fine solid line) and after (bold solid line) neurodevelopmental training. Increasing degree of each angular movement indicates flexion (dorsiflexion). T1 and T3 indicate the initial and end points of the sit-to-stand movement, respectively. T2 indicates the point when the participant’s weight was off the buttocks; T2 was the mid-point of the movement duration. Table 3. Sit-to-stand angular movements. Spastic diplegia cerebral palsy (n ¼ 16 limbs)
Typically developing children (n ¼ 10 limbs)
Before NDT Mean (SD)
After NDT Mean (SD)
p
d
Mean (SD)
Trunk forward tilt Initial angle Maximum angle Final angle
16.4 (10.1) 33.1 (11.9) 24.6 (6.9)
15.4 (9.0) 28.0 (8.7) 18.3 (7.5)
0.691 0.032 50.01
0.11 0.49 0.88
6.8 (3.2) 31.0 (5.4) 7.0 (3.2)
Hip flexion Initial anglea Maximum anglea Final angle
101.4 (15.0) 112.0 (12.4) 54.7 (13.5)
98.7 (13.7) 106.4 (10.0) 43.9 (9.5)
0.196 0.121 50.01
0.19 0.50 0.93
89.8 (10.0) 109.7 (8.3) 15.9 (8.3)
Knee flexion Initial angle Maximum angle Final angle
88.1 (8.6) 98.2 (9.6) 45.3 (13.8)
89.8 (6.1) 97.0 (7.7) 42.3 (7.5)
0.310 0.613 0.360
0.23 0.14 0.27
91.3 (11.2) 94.0 (11.5) 16.8 (10.3)
15.1 (11.2) 8.4 (12.6) 19.9 (15.5)
7.5 (9.0) 0.4 (9.6) 10.4 (9.6)
0.040 50.01 0.030
0.75 0.79 0.74
2.4 (7.2) 14.4 (8.2) 1.9 (7.2)
Joint angle
Ankle dorsiflexion Initial angle Maximum angle Final angle
NDT, neurodevelopmental treatment and SD, standard deviation. Cohen’s d: small 0.2; medium 0.5; and large 0.8. Median (range) reported due to non-normal distribution of data, analyzed with Wilcoxon’s signed rank-sum test.
a
6
R. Yonetsu et al.
Disabil Rehabil, Early Online: 1–8
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
Figure 5. The averaged kinematic curves (A, typically-developing children; B, before neurodevelopmental training in children with spastic diplegia cerebral palsy; and C, after neurodevelopmental training in children with spastic diplegia cerebral palsy) for the hip and the knee joints. Solid and dashed lines indicate the hip and knee angular movements, respectively. Gray space represents from T2 to T3 (Phase II).
different from those before the session. On the other hand, the initial, maximum and final ankle dorsiflexion angles measured after the session increased significantly (p50.05, d ¼ 0.75; p50.01, d ¼ 0.79; p50.05, d ¼ 0.74, respectively) compared with those before the intervention (Table 3). Moreover, after the session, the point of maximum angle in the CP participants occurred earlier than in the normal controls (Figure 4D). Finally, the final angles for the trunk forward tilt and hip and knee flexion after the session remained greater than those for the normal controls; whereas, those for ankle dorsiflexion remained lower (Table 3). The averaged kinematic curves for the hip and knee joints during phase II, in the control and CP children, before and after NDT, are also shown in Figure 5 (A, control children; B, CP children before the NDT session; and C, CP children after the NDT session). This figure indicates that both joints were locked together in a more linear extension pattern after the NDT session (Figure 5C) than before the NDT session (Figure 5B).
Discussion The primary goal of this study was to asses STS movements before and after a single NDT session in preschool-aged children with CP who had limited ability to transfer from sitting positions. The secondary goal was to understand how far STS movements, in subjects with CP, moved towards normal after one NDT session. Thus, this pilot study attempted to provide a better understanding of the effects of a single NDT session on changes in STS movements in children with CP. Based on the results of a previous case study [6], the NDT session was hypothesised to enable children with CP to stand after being seated on a bench without using atypical movement patterns. Although the findings of this study are preliminary because of its small sample size and research design, the statistically significant findings and the medium to large effect sizes, support the hypothesis to some extent. Trunk forward tilt during the STS movement is important when shifting the body’s centre of mass forward [25,26]. As shown in Figure 4A, this trunk movement generally occurs until the hips lift off the seat and the base of support transfers from the buttocks to the feet. However, in CP participants, the point of the maximum angle, before the session, occurred after the hips were raised off the seat (Figure 4A). This finding suggests that children with spastic diplegia CP have difficulty shifting their centre of mass forward, resulting in the use of excessive forward tilt to accomplish this task [4,6]. This study also showed that the maximum angle of the forward trunk tilt was significantly larger (Table 3) prior to the intervention, corresponding with the reports
of earlier studies [4,6]. In contrast, this angle decreased significantly after the NDT session, suggesting that the atypical compensatory trunk movement diminished and that the centre of mass shifted forward more efficiently. The trunk forward tilt movements, observed during phase I, might affect the shanks during forward tilt. In general, the shanks also tilt forward during the STS movement, aiding the forward shift towards the centre of mass, following the forward tilt of the trunk [25]. Consequently, as shown in Figure 4D, ankle dorsiflexion was observed during the STS movement immediately after the hips were raised off the seat [25]. However, this study demonstrated that before the intervention, the maximum angle in CP participants was observed when the hips were lifted off the seat (Figure 4D). Moreover, the ankle joints showed minimal dorsiflexion during phase I (Figure 4D), indicating that the CP participants could not completely tilt their shanks forward. After the NDT session, the maximum angle was still observed when the hips were lifted off the seat and the ankle joints were still in plantarflexion, but dorsiflexion occurred between T1 and T2. Thus, the maximum angle of ankle dorsiflexion after NDT session was significantly larger (Table 3). This finding helps explain why the CP participants could more efficiently shift their centre of mass forward after the NDT session. Moreover, different movements, while shifting the centre of mass forward in phase I, require each participant to select a different strategy for aligning the body between the hip and knee joints during phase II. During the STS movement in healthy young adults, the hip and knee joints extend and lock together in a linear pattern after the hips have lifted off the seat [23], similar to that observed in the normal controls (Figure 5A). However, excessive hip flexion was observed among our CP children before the NDT session (Table 3), indicating that they could not extend their hip and knee joints in a coordinated manner (Figure 5B). After the NDT session, however, these joints locked together in a linear pattern to a greater extent than they did before the session (Figure 5C). This phenomenon could be due to hip extension, as shown in Figure 4B. Hence, the duration of phase II, after the NDT session, was significantly shorter (Table 2). Finally, contrasting findings were observed between the measurements at T3 before and after the NDT session. Although the final angles of the joints after the NDT session, for the CP participants, were drastically different from those of the normal controls, there were significant changes in the trunk forward tilt and hip flexion angles at T3 following the intervention (Table 3). These findings demonstrate that the CP participants gained the ability to extend their body vertically after the session. Moreover, the ankle dorsiflexion angle at T3 increased after the
STS movement changes in CP following NDT
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
NDT session (Table 3), suggesting that the CP participants gained the ability to shift their weight from their forefoot to their heels while standing. Thus, the total duration of the STS movements was significantly less after the NDT session (Table 2). However, the STS movement changes may be due to the initial position of the ankle joint, before the intervention, being significantly different from that after the intervention (Table 3). In other words, the increased ankle dorsiflexion angle at T1, after the NDT session, might have led each CP participant to perform the STS movement without some atypical movement patterns. This was addressed in a study by Park et al. [27] that investigated the use of ankle foot orthoses (AFOs) on STS movements in children with CP. Their study demonstrated that the proximal compensatory strategy of the increased pelvic tilt and hip flexion did not change despite increased initial ankle dorsiflexion resulting from the use of AFOs. Thus, movements in CP patients might be affected by strong, atypical compensatory patterns rather than by the initial position of the ankle joint. Improved alignment and/or equilibrium reactions and body coordination could, therefore, be assumed to improve because the NDT session, contradicting the observations of Park et al. [27]. Therefore, facilitating more normalised movements instead of repeated atypical movement patterns is important for improving mobility in young children with CP. There were several limitations to this study. A major limitation was the lack of a control group undergoing a different intervention; the inclusion of such a group would have increased the possibility of detecting a learning effect caused by repeated STS movements instead of observing a real improvement caused by the NDT session. Moreover, we cannot present a reliability index, such as an intraclass correlation coefficient. Our data from the three trials differed since each participant could not always perform accurately, according to our instructions. This issue might be attributable to younger age of the participants and/or the longer measurement. Just like the small sample size, this limitation also restricts the generalisation of these findings. Furthermore, this study could not clarify how using upper limbs affects STS movements before and after the NDT session. By recruiting CP participants who can stand up without using a grip bar, a better understanding of STS movements would be obtained. Finally, the outcome measurement of this study was range of motion. Another outcome, such as electromyography, would provide a multilateral understanding of the effects of NDT on STS movements in children with CP. Recent investigations of lower limb strength training programs have demonstrated increased muscle strength in children with CP without evidence of increased spasticity or atypical movements [28–30]. To plan a more efficient therapeutic program, further studies involving a different study design and a larger number of participants is needed. To some extent, our findings support the hypothesis that a single NDT session can enable preschool-aged children with CP to stand using proper body mechanics. That is, after the NDT session, STS movements were more efficient in terms of selective muscle control. However, this study only showed the immediate effect of NDT, without assessing the long-term effects of NDT. Although the NDT session inhibited atypical movement patterns, this study demonstrated that the ankle joints angles, after the session, remained drastically smaller than those of the normal control children (Table 3 and Figure 4D). In this sense, increasing ankle dorsiflexion during STS might facilitate children with CP developing more coordinated STS movements. Park et al. [31] investigated the effects of BTA injection into the gastrocnemius muscle on STS movements in children with CP. That study suggested that a large reduction in spasticity could increase the ankle dorsiflexion angle and decrease the trunk forward tilt and
7
hip flexion angles. Thus, combining NDT with BTA injections is worth considering for children with CP, as this combination may enhance carryover in the STS movements. Maintaining these improvements might lead preschool-aged children with spastic diplegia CP to develop improved mobility, which would enhance their ADL and social participation.
Conclusions This study demonstrated that a single NDT session can improve STS movements by allowing the use of forward shank tilting in CP participants, without increasing the trunk forward tilt. After the subject’s hips were off the seat, the hip and knee joints locked together to balance the STS movements. Finally, the CP participants could extend their body vertically, without increasing ankle plantarflexion, while standing. These findings indicate that a single NDT session enabled preschool-aged children with spastic diplegia CP to stand from a seated position without using some of their atypical compensatory movement patterns immediately after the NDT session. Although this study could not examine the long-term effects of NDT, this information is invaluable for therapists planning NDT therapeutic programs for children with CP.
Declaration of interest The authors report no conflicts of interest. This study was supported by a Grant-in-Aid for Young Scientists (B) from the Japan Society for the Promotion of Science (23700618).
References 1. Wang T-H, Liao H-F, Peng Y-C. Reliability and validity of the fiverepetition sit-to-stand test for children with cerebral palsy. Clin Rehabil 2012;26:664–71. 2. Chrysagis N, Skordilis E, Koutsouki D. Validity and clinical utility of functional assessments in children with cerebral palsy. Arch Phys Med Rehab 2014;95:369–74. 3. Bobath K. Neurophysiological basis for the treatment of cerebral palsy. London: Mac Keith Press; 1991. 4. Park ES, Park CI, Lee HJ, et al. The characteristics of sit-to-stand transfer in young children with spastic cerebral palsy based on kinematic and kinetic data. Gait Posture 2003;17:43–9. 5. Hennington G, Johnson J, Penrose J, et al. Effect of bench height on sit-to-stand in children without disabilities and children with cerebral palsy. Arch Phys Med Rehabil 2004;85:70–6. 6. Yonetsu R, Shimizu J, Surya J. The effect of physiotherapy on sit-tostand movements in a child with spastic diplegia. Disabil Rehabil 2010;32:598–605. 7. World Health Organization. International Classification of Functioning, Disability and Health. ICF. Geneva: WHO Publishing; 2001. 8. Butler C, Darrah J. Effects of neurodevelopmental treatment (NDT) for cerebral palsy: an AACPDM evidence report. Dev Med Child Neurol 2001;43:778–90. 9. Raine S, Meadows L, Lynch-Ellerington M. Bobath concept: theory and clinical practice in neurological rehabilitation. London: WileyBlackwell; 2009. 10. Tsorlakis N, Evaggelinou C, Grouios G, Tsorbatzoudis C. Effect of intensive neurodevelopmental treatment in gross motor function of children with cerebral palsy. Dev Med Child Neurol 2004;46: 740–5. 11. Ketelaar M, Vermeer A, Hart H, et al. Effects of a functional therapy program on motor abilities of children with cerebral palsy. Phys Ther 2001;81:1534–45. 12. Adams M, Chandler L, Schulmann K. Gait change in children with cerebral palsy following a neurodevelopmental treatment course. Pediatr Phys Ther 2000;12:114–20. 13. Trahan J, Malouin F. Changes in the gross motor function measure in children with different types of cerebral palsy: an eight-month follow-up study. Pediatr Phys Ther 1999;11:12–17.
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
8
R. Yonetsu et al.
14. Bower E, Mclellan D. Assessing motor-skill acquisition in four centres for the treatment of children with cerebral palsy. Dev Med Child Neurol 1994;36:902–9. 15. Palmer FB, Shapiro BK, Wachtel RC, et al. The effects of physical therapy on cerebral palsy: a controlled trial in infants with spastic diplegia. N Engl J Med 1988;318:803–8. 16. Embery D, Yates L, Mott D. Effects of neurodevelopmental treatment and orthoses on knee flexion during gait: a single-subject design. Phys Ther 1990;70:626–37. 17. Laskas C, Mullen S, Nelson D, Willson-Broyles M. Enhancement of two motor functions of the lower extremity in a child with cerebral palsy. Phys Ther 1985;65:11–16. 18. Jonsdottir J, Fetter L, Kluzik J. Effects of physical therapy on postural control in children with cerebral palsy. Pediatr Phys Ther 1997;9:68–75. 19. Bohannon RW, Smith MB. Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther 1987;67: 206–7. 20. Palisano RJ, Rosenbaum P, Bartlett D, Livingston MH. Content validity of the expanded and revised Gross Motor Function Classification System. Dev Med Child Neurol 2008;50: 744–50. 21. Roy G, Nadeau S, Gravel D, et al. The effect of foot position and chair height on the asymmetry of vertical forces during sit-to-stand and stand-to-sit tasks in individuals with hemiparesis. Clin Biomech (Bristol, Avon) 2006;21:585–93. 22. Camargos AC, Rodrigues-de-Paula-Goulart F, Teixeira-Salmela LF. The effects of foot position on the performance of the sit-to-stand
Disabil Rehabil, Early Online: 1–8
23. 24. 25. 26. 27. 28. 29. 30.
31.
movement with chronic stroke subjects. Arch Phys Med Rehabil 2009;90:314–19. Tully EA, Fotoohabadi MR, Galea MP. Sagittal spine and lower limb movement during sit-to-stand in healthy young subjects. Gait Posture 2005;19:338–45. Cohen J. A power primer. Psychol Bull 1992;11:155–9. Riley PO, Schneckman ML, Mann RW, Hodge WA. Mechanics of a constrained chair-rise. J Biomech 1991;24:77–85. Rodosky MW, Andriacchi TP, Andersson GB. The influence of chair height on lower limb mechanics during rising. J Orthop Res 1989;7: 266–71. Park ES, Park CI, Chang HJ, et al. The effect of hinged ankle-foot orthoses on sit-to-stand transfer in children with spastic cerebral palsy. Arch Phys Med Rehabil 2004;85:2053–7. Dodd KJ, Taylor NF, Damiano DL. A systematic review of the effectiveness of strength-training programs for people with cerebral palsy. Arch Phys Med Rehabil 2002;83:1157–64. Fowler EG, Ho TW, Nwigwe AI, Dorey FJ. The effect of quadriceps femoris muscle strengthening exercises on spasticity in children with cerebral palsy. Phys Ther 2001;81:1215–23. Liao HF, Gan SM, Lin KH, Lin JJ. Effects of weight resistance on the temporal parameters and electromyography of sit-to-stand movements in children with and without cerebral palsy. Am J Phys Med Rehabil 2010;89:99–106. Park ES, Park CI, Chang HC, et al. The effect of botulinum toxin type A injection into the gastrocnemius muscle on sit-to-stand transfer in children with spastic diplegic cerebral palsy. Clin Rehabil 2006;20:668–74.
RESEARCH PAPER
Sit-to-stand movement changes in preschool-aged children with spastic diplegia following one neurodevelopmental treatment session – a pilot study Ryo Yonetsu1, Akira Iwata1, John Surya2, Kazunori Unase3, and Junichi Shimizu4 Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
1
Department of Physical Therapy, Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Osaka, Japan, 2Department of Physical Therapy, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan, 3Osaka Developmental Rehabilitation Center, Osaka, Japan, and 4Department of Occupational Therapy, Tokyo University of Technology, Tokyo, Japan
Abstract
Keywords
Purpose: This study was designed to provide a better understanding of how a single neurodevelopmental treatment (NDT) session affects sit-to-stand (STS) movements in children with cerebral palsy (CP). Methods: Eight children with spastic diplegia and five typically developing children, aged 4–6 years, participated in this study. The CP participants performed STS movements immediately before and after a 40-min NDT session. Using a three-dimensional, four-camera analysis system, angular movements involving the hip, knee and ankle joints of the participants were obtained. Results: During forward tilt of the trunk, the maximum and final angles after the NDT session significantly decreased compared with those before the session (p50.05, p50.01). Moreover, the final hip flexion after the session also significantly decreased compared with that before the session (p50.01). On the other hand, the initial, maximum and final ankle dorsiflexion angles after the session were significantly greater (p50.05, p50.01 and p50.05, respectively) than before the session. Conclusions: These findings suggest that a single NDT session enables children with CP to stand from a seated position without using some atypical movement patterns.
Motion analysis, neurodevelopmental treatment, sit-to-stand movement, spastic diplegia History Received 5 December 2013 Revised 19 September 2014 Accepted 30 September 2014 Published online 20 October 2014
ä Implications for Rehabilitation
Preschool-aged children with spastic diplegia, with limited ability to independently transfer from a sitting position, and dependent on a wheelchair for mobility experience obstacles to enhanced activities of daily life and social participation. A single neurodevelopmental treatment session would enable children with spastic diplegia to perform sit-to-stand movements more efficiently, with selective muscle control. Understanding how a single neurodevelopmental treatment session affects sit-to-stand movements in children with spastic diplegia is invaluable for therapists planning more efficient therapeutic programs and may enable children with spastic diplegia to develop improved mobility
Introduction The ability to stand after being seated in a chair, called the sit-tostand (STS) movement, is a fundamental activity for upright mobility and a prerequisite for many functional activities. Thus, STS movement is an important goal for improving mobility in children with cerebral palsy (CP). Recently, the five-repetition STS test that has good reliability and validity was introduced for the assessment of muscle weakness and its post-interventional clinical change as an outcome variable for children with CP [1,2]. However, assessments using this test are limited to children with CP in a prestanding status because many children with CP Address for correspondence: Ryo Yonetsu, 3-7-30 Habikino, Habikino, Osaka 583-8555, Japan. Tel: +81 72 950 2872. Fax: +81 72 950 2130. E-mail: [email protected]
demonstrate difficulty in independently accomplishing the STS movement. Particularly, early in life, children with CP manifest loss of selective muscle control, dependence on primitive reflex patterns, relative imbalance between muscle agonist and antagonist activities and deficient equilibrium reactions [3]. Therefore, STS movements in children with CP are characterised by various compensatory patterns [4–6]. Based on the International Classification System of Functioning Disability and Health framework [7], preschool-aged children with CP who are dependent on a wheelchair or assistive buggy for functional mobility have a limited ability to independently transfer from a sitting position, which becomes an obstacle to activities of daily life (ADL) and social participation. Neurodevelopmental treatment (NDT) is the predominant method for treating children with CP [2,8]. This approach focuses on establishing normal sensorimotor components such as muscle
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
2
R. Yonetsu et al.
tone and reflexes or on inhibiting atypical movement patterns to improve functional movements. This treatment outcome is achieved through physical support of the child during movement. As the child gains postural control, the therapist gradually withdraws support. In this way, one of the goals of NDT is to facilitate repeated, active movements involving postural control and functional goals [9]. Most studies on the effectiveness of NDT have found motor performance improvements, especially in gross motor ability [10–15]. Although few studies have demonstrated how NDT encourages normal movement patterns and diminishes atypical patterns during functional movements (reaching, standing and gait) in individuals with CP [16–18], a study focused on STS movements has not been reported. More information regarding how NDT affects STS movements would be advantageous for therapists designing and planning more efficient programs. A previous case study [6] attempted to assess the STS movement immediately before and after a single NDT session in a child with spastic diplegia CP who could not stand without assistance. The study found that after one NDT session, the subject could maintain ankle dorsiflexion from the initial to the final position, decrease forward tilt of the trunk when the subject’s hips lifted off the chair seat and lock the hip and knee joints in a linear extension pattern after the hips were off the seat during the STS movement. These findings led to the conclusion that after one NDT session, STS movements were more efficient. However, this conclusion was based on data from a single subject. Therefore, using a larger sample, this pilot study was designed to provide a better understanding of the effects of a single NDT session on the STS movements in preschool-aged children with CP who had a limited ability to transfer from sitting positions. The primary goal of this study was to asses STS movements before and after one NDT session in these children. The working hypothesis was that a single NDT session would enable these children to stand from a chair without using atypical movement patterns. Based on a previous case study [6], STS movements after single NDT sessions were hypothesised to have the following characteristics compared to those before the session: (i) diminished excessive trunk forward tilt, (ii) maintenance of ankle dorsiflexion and (iii) hip and knee joints locked in a linear pattern of extension. Thus, children with CP would be able to extend their body vertically without increasing their ankle plantarflexion while standing. The secondary goal was to understand how far STS movements, after one NDT session, moved towards normal in subjects with CP. These efforts would help children with CP enhance their ADL and social participation.
Methods Study design The aim of this pilot study was to provide a better understanding of the effects of one NDT session on STS movements in subjects with CP. A single-group, before-and-after design was employed. Children with CP received a single, 40-min physiotherapy session at their convenience. One session of regular NDT-based physiotherapy was regarded as a single NDT session. Each patient completed a pretest and posttest assessment immediately before and after their sessions. By assessing the STS movements in normally developing children, the extent to which STS movements moved towards normal after a single NDT session for CP patients was also investigated. Participants Participants were recruited from the Osaka (Japan) Developmental Rehabilitation Centre between March 2010 and December 2012. A convenience sampling of eight preschool-aged
Disabil Rehabil, Early Online: 1–8
Table 1. Participant profiles. Age Height Weight Participant (months) Gender (cm) (kg) 1 2 3 4 5 6 7 8
50 52 52 55 62 69 69 69
Boy Girl Boy Boy Boy Boy Girl Boy
97 86 87 85 91 93 98 102
13.7 10.2 13.5 12.6 11.2 15.9 12.6 15.8
Functional mobility Wheelchair Wheelchair Buggy Buggy Wheelchair or walker Wheelchair or walker Walker or wheelchair Wheelchair or walker
children with spastic diplegia CP (six boys, two girls), with limited ability to transfer from sitting positions, participated in this pilot study (Table 1). All participants had received regular NDT-based physiotherapy more than once a week (40 min per session) for the previous three months at this rehabilitation centre. The study’s inclusion criteria were as follows: (i) ability to independently maintain a sitting position on a bench and the ability to stand with the assistance of a grip bar; (ii) 4–6 years of age; (iii) grade 1 to grade 2 score according to the modified Ashworth scale [19]; (iv) absence of joint contracture and fixed deformities; (v) no previous remedial orthopaedic surgery or medication to reduce spasticity during the previous 6 months [1,2]; (vi) absence of visual or auditory problems; and (vii) ability to understand verbal commands. Consequently, all participants were classified as Gross Motor Function Classification System [20]. Level III; three children had undergone muscle release operations or received botulinum toxin type A (BTA) injections. In addition, five match-aged typically developing children (two boys, three girls; mean age, 61 years; SD 10 months) were included as normal controls. This research was conducted after the Osaka Prefecture University Research Ethics Committee (2009–06) had approved the study. The purpose of this study was explained to the participants’ parents both orally and in writing, and written consent was obtained. Intervention Three physiotherapists administered the interventions. Each therapist was certified in paediatric NDT and had more than 10 years’ experience [6]. Each CP participant received one, 40-min NDT session from one of the physiotherapists. Although the treatment activities varied for each CP participant, the overall goals (improved smoothness and efficiency of movement), which included improved trunk, hip, knee and ankle control during the STS movement, were the same for all CP participants. All sessions incorporated handling techniques that aimed to alter muscle tone during movement and to facilitate antigravity, weight-shifting and postural reactions [9]. Consequently, the standing position accounted for more than half of each participant’s total treatment. An adjustable-height desk with toys placed on it was prepared in front of each CP participant. The height of this desk was as high each CP participant’s sternal xiphoid process when the participant was standing. The support surface of this desk was 60 cm wide and 50 cm long. The toys that were selected were ones that could be held and manually manipulated by the child (e.g. cups, spoons and stones). The physiotherapist manipulated both knee joints of each CP participant to facilitate hip and knee extension (Figure 1A). Moreover, the physiotherapist facilitated weight-shifting and postural reactions during reaching actions (Figure 1B). If the CP participant could extend their hips and knees easily, the physiotherapist gradually decreased the degree of handling (Figure 1C). With this
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
STS movement changes in CP following NDT
3
Figure 1. Examples of the neurodevelopmental training approach for children with spastic diplegia cerebral palsy. (A) The physiotherapist manipulates both knee joints of the participant to facilitate hip and knee extension and postural reactions. (B) The physiotherapist facilitates weight-shifting and postural reactions during forward reaching actions (C) If the participant can extend their hips and knees easily, the physiotherapist gradually decreases the degree of handling.
type of support, each CP participant developed enhanced control of their posture and motion while playing [9]. Incidentally, since NDT focuses on enhancing body righting and equilibrium reactions [9], each physiotherapist was prohibited from intentionally duplicating STS movement, which may have affected the final outcome. Procedures In order to assess STS movements, a grip bar, a motion analysis system (Kinema Tracer, Kissei Comtec, Matsumoto, Japan) with four cameras (30 Hz), and a novel pressure-sensitive trigger device (100 Hz) were used. Two cameras were placed on each side of the child, perpendicular and oblique to their sagittal plane. The pressure-sensitive trigger device, which detected and recorded the loss of contact with the seat (when the participant’s weight was reduced by 53 kg), was placed on the bench and was synchronised with the four-camera motion analysis system. Markers were placed on both sides of the lateral aspect of each participant’s fifth metatarsal head, lateral malleolus, lateral femoral condyle, greater trochanter and acromion [6]. The STS movements were performed with each participant barefoot and their feet on the floor. Each participant used a bench, the height of which was adjusted to the leg length of each participant to allow positioning of the ankle, knee and hip joints as close to 90 as possible. Both feet were kept at shoulder-width apart on the floor, with the hands on the knees. A bar at the height of the seated participant’s shoulder joint was placed in front of the bench at a distance equal to the length of the upper extremity with the shoulder joint at 90 flexion. Each participant was asked to rise from the bench in his or her usual manner by using the grip bar. If a participant performed the STS movement with additional antics, such as rotating head or pulling the bar backwards and forwards in the standing posture, additional instructions were given. Instructions that might affect STS movement patterns, such as ‘‘Pull your feet’’, were not given [21,22]. Each participant executed the STS movements three times before and after the single NDT session; for analysis, the most symmetric movement among each of the three trials was selected [6]. Data analysis Data analysis was performed by another physiotherapist who did not administer the intervention. The initial point of the STS
motion (T1) was defined as the point at which each hand started to move, and the end point of the STS motion (T3) was defined as the point at which the motion of the trunk or knees stopped. The point at which the individual’s weight was off the buttocks (T2) was measured, based on data derived from the trigger device, and was defined as the point at which the electrical waveform was at its lowest voltage. In this way, the total duration of the STS movement and the durations of the other phases (phase I [T1 to T2], forward transfer to phase II [T2 to T3] and standing) of the STS movement from the three transitional points were also assessed. Angular movements involving the trunk and hips, the knees and the ankle joints of the participants (involving the 16 lower limbs) were collected. The angular movements of each joint are defined in Figure 2. Briefly, the angular movement of the trunk forward tilt (A) occurred between an imaginary line extending from the acromion to the greater trochanter and a vertical line extending through the greater trochanter. Similarly, angular hip movement (B) occurred between the line extended from the acromion to the greater trochanter and a line connecting the greater trochanter and the lateral femoral condyle. Angular knee movement (C) occurred between the line extended from the greater trochanter to the lateral femoral condyle and a line connecting the lateral femoral condyle and the lateral malleolus. Angular ankle movement (D) occurred between a vertical line extended from the lateral femoral condyle to the lateral malleolus and a line connecting the lateral malleolus and the lateral aspect of the fifth metatarsal head. In healthy young adults, the hip and knee joints extend and lock together in a linear pattern after a subject’s hips lift off the seat [23]. The angular movements of the hip and knee joints between T2 and T3 were converted to 100% to reveal the relationship between the hip and knee joints after the hips were lifted off the seat. In this manner, averaged kinematic curves were drawn to represent the relationship between the movements of these joints. In order to examine within-group differences, before and after the NDT session, descriptive statistics were generated for all demographic variables. Based on the output from the Shapiro– Wilk’s test, the angular movement data, except for hip flexion after NDT at T1 and T2, were normally distributed; therefore, parametric tests were used for the analysis. A paired t-test was conducted to examine within-group differences before and after
4
R. Yonetsu et al.
Disabil Rehabil, Early Online: 1–8
the NDT session. Wilcoxon’s signed rank-sum test was conducted for the assessment of hip flexion at T1 and T2 due to the nonnormal distribution of data. For the analysis of the duration of the STS time, Wilcoxon’s signed rank-sum test was used due to the small number of data. p Values50.05 were considered statistically significant.
Effect sizes were calculated to examine the magnitude of change and interpreted based on Cohen’s proposed conventional values for t-tests for means that are small ¼ 0.2, medium ¼ 0.5 and large ¼ 0.8 [24]. Data comparison between normal control and CP participants after the NDT session were not subject to a statistical analysis; these data were regarded as supplemental reference values.
Results
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
Total duration of the STS movement After the NDT session, seven of the eight CP participants showed a decreased total duration of the STS movements compared with that before the NDT session (Figure 3A). The average duration of the STS movements, after the NDT session was less than before the intervention (p50.05, d ¼ 0.73) (Table 2). Moreover, the duration of phase II decreased, for all CP participants, after the NDT session (p50.05, d ¼ 0.78) (Figure 3C and Table 2). The duration of STS movements in the children with CP lasted longer even after the NDT session than in the normal control children (Table 2). Angular movements of each joint
Figure 2. The definitions of angular movements of each joint (A, trunk; B, hip; C, knee; and D, ankle).
The averaged kinematic curves are shown in Figure 4 (A, trunk; B, hip; C, knee; and D, ankle joints, respectively). After the NDT session, the maximum and the final angles of the trunk’s forward tilt significantly decreased compared with those before the session (p50.05, d ¼ 0.49 and p50.01, d ¼ 0.88, respectively; Table 3). Although the maximum angle after the session was not different between the children with CP and the normal controls, the point of maximum angle occurred later than in the controls (Figure 4A). After the session, the final hip flexion angles were also significantly decreased compared with those before the session (p50.01, d ¼ 0.93; Table 3). However, the knee flexion angles, measured after the session, were not significantly
Figure 3. The duration of sit-to-stand movements before and after one neurodevelopmental treatment (A, total duration; B, phase I; and C, phase II) in children with spastic diplegia cerebral palsy. *p50.05.
Table 2. The duration of sit-to-stand movements. Spastic diplegia cerebral palsy (n ¼ 8)
Total duration (s) Phase I (s) Phase II (s)
Typically developing children (n ¼ 5)
Before NDT Mean (SD)
After NDT Mean (SD)
p
d
Mean (SD)
3.82 (1.69) 1.94 (0.73) 1.88 (1.02)
2.88 (0.71) 1.65 (0.22) 1.23 (0.59)
0.036 0.223 0.012
0.73 0.54 0.78
2.19 (0.59) 1.20 (0.59) 0.99 (0.34)
NDT, neurodevelopmental treatment and SD, standard deviation. Phase I, the time between T1 and T2 and Phase II, the time between T2 and T3. Cohen’s d: small 0.2; medium 0.5; and large 0.8.
STS movement changes in CP following NDT
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
5
Figure 4. The averaged curves of angular movement (A, trunk; B, hip; C, knee; and D, ankle joints) in typically-developing (dashed line) children and in children with spastic diplegia cerebral palsy before (fine solid line) and after (bold solid line) neurodevelopmental training. Increasing degree of each angular movement indicates flexion (dorsiflexion). T1 and T3 indicate the initial and end points of the sit-to-stand movement, respectively. T2 indicates the point when the participant’s weight was off the buttocks; T2 was the mid-point of the movement duration. Table 3. Sit-to-stand angular movements. Spastic diplegia cerebral palsy (n ¼ 16 limbs)
Typically developing children (n ¼ 10 limbs)
Before NDT Mean (SD)
After NDT Mean (SD)
p
d
Mean (SD)
Trunk forward tilt Initial angle Maximum angle Final angle
16.4 (10.1) 33.1 (11.9) 24.6 (6.9)
15.4 (9.0) 28.0 (8.7) 18.3 (7.5)
0.691 0.032 50.01
0.11 0.49 0.88
6.8 (3.2) 31.0 (5.4) 7.0 (3.2)
Hip flexion Initial anglea Maximum anglea Final angle
101.4 (15.0) 112.0 (12.4) 54.7 (13.5)
98.7 (13.7) 106.4 (10.0) 43.9 (9.5)
0.196 0.121 50.01
0.19 0.50 0.93
89.8 (10.0) 109.7 (8.3) 15.9 (8.3)
Knee flexion Initial angle Maximum angle Final angle
88.1 (8.6) 98.2 (9.6) 45.3 (13.8)
89.8 (6.1) 97.0 (7.7) 42.3 (7.5)
0.310 0.613 0.360
0.23 0.14 0.27
91.3 (11.2) 94.0 (11.5) 16.8 (10.3)
15.1 (11.2) 8.4 (12.6) 19.9 (15.5)
7.5 (9.0) 0.4 (9.6) 10.4 (9.6)
0.040 50.01 0.030
0.75 0.79 0.74
2.4 (7.2) 14.4 (8.2) 1.9 (7.2)
Joint angle
Ankle dorsiflexion Initial angle Maximum angle Final angle
NDT, neurodevelopmental treatment and SD, standard deviation. Cohen’s d: small 0.2; medium 0.5; and large 0.8. Median (range) reported due to non-normal distribution of data, analyzed with Wilcoxon’s signed rank-sum test.
a
6
R. Yonetsu et al.
Disabil Rehabil, Early Online: 1–8
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
Figure 5. The averaged kinematic curves (A, typically-developing children; B, before neurodevelopmental training in children with spastic diplegia cerebral palsy; and C, after neurodevelopmental training in children with spastic diplegia cerebral palsy) for the hip and the knee joints. Solid and dashed lines indicate the hip and knee angular movements, respectively. Gray space represents from T2 to T3 (Phase II).
different from those before the session. On the other hand, the initial, maximum and final ankle dorsiflexion angles measured after the session increased significantly (p50.05, d ¼ 0.75; p50.01, d ¼ 0.79; p50.05, d ¼ 0.74, respectively) compared with those before the intervention (Table 3). Moreover, after the session, the point of maximum angle in the CP participants occurred earlier than in the normal controls (Figure 4D). Finally, the final angles for the trunk forward tilt and hip and knee flexion after the session remained greater than those for the normal controls; whereas, those for ankle dorsiflexion remained lower (Table 3). The averaged kinematic curves for the hip and knee joints during phase II, in the control and CP children, before and after NDT, are also shown in Figure 5 (A, control children; B, CP children before the NDT session; and C, CP children after the NDT session). This figure indicates that both joints were locked together in a more linear extension pattern after the NDT session (Figure 5C) than before the NDT session (Figure 5B).
Discussion The primary goal of this study was to asses STS movements before and after a single NDT session in preschool-aged children with CP who had limited ability to transfer from sitting positions. The secondary goal was to understand how far STS movements, in subjects with CP, moved towards normal after one NDT session. Thus, this pilot study attempted to provide a better understanding of the effects of a single NDT session on changes in STS movements in children with CP. Based on the results of a previous case study [6], the NDT session was hypothesised to enable children with CP to stand after being seated on a bench without using atypical movement patterns. Although the findings of this study are preliminary because of its small sample size and research design, the statistically significant findings and the medium to large effect sizes, support the hypothesis to some extent. Trunk forward tilt during the STS movement is important when shifting the body’s centre of mass forward [25,26]. As shown in Figure 4A, this trunk movement generally occurs until the hips lift off the seat and the base of support transfers from the buttocks to the feet. However, in CP participants, the point of the maximum angle, before the session, occurred after the hips were raised off the seat (Figure 4A). This finding suggests that children with spastic diplegia CP have difficulty shifting their centre of mass forward, resulting in the use of excessive forward tilt to accomplish this task [4,6]. This study also showed that the maximum angle of the forward trunk tilt was significantly larger (Table 3) prior to the intervention, corresponding with the reports
of earlier studies [4,6]. In contrast, this angle decreased significantly after the NDT session, suggesting that the atypical compensatory trunk movement diminished and that the centre of mass shifted forward more efficiently. The trunk forward tilt movements, observed during phase I, might affect the shanks during forward tilt. In general, the shanks also tilt forward during the STS movement, aiding the forward shift towards the centre of mass, following the forward tilt of the trunk [25]. Consequently, as shown in Figure 4D, ankle dorsiflexion was observed during the STS movement immediately after the hips were raised off the seat [25]. However, this study demonstrated that before the intervention, the maximum angle in CP participants was observed when the hips were lifted off the seat (Figure 4D). Moreover, the ankle joints showed minimal dorsiflexion during phase I (Figure 4D), indicating that the CP participants could not completely tilt their shanks forward. After the NDT session, the maximum angle was still observed when the hips were lifted off the seat and the ankle joints were still in plantarflexion, but dorsiflexion occurred between T1 and T2. Thus, the maximum angle of ankle dorsiflexion after NDT session was significantly larger (Table 3). This finding helps explain why the CP participants could more efficiently shift their centre of mass forward after the NDT session. Moreover, different movements, while shifting the centre of mass forward in phase I, require each participant to select a different strategy for aligning the body between the hip and knee joints during phase II. During the STS movement in healthy young adults, the hip and knee joints extend and lock together in a linear pattern after the hips have lifted off the seat [23], similar to that observed in the normal controls (Figure 5A). However, excessive hip flexion was observed among our CP children before the NDT session (Table 3), indicating that they could not extend their hip and knee joints in a coordinated manner (Figure 5B). After the NDT session, however, these joints locked together in a linear pattern to a greater extent than they did before the session (Figure 5C). This phenomenon could be due to hip extension, as shown in Figure 4B. Hence, the duration of phase II, after the NDT session, was significantly shorter (Table 2). Finally, contrasting findings were observed between the measurements at T3 before and after the NDT session. Although the final angles of the joints after the NDT session, for the CP participants, were drastically different from those of the normal controls, there were significant changes in the trunk forward tilt and hip flexion angles at T3 following the intervention (Table 3). These findings demonstrate that the CP participants gained the ability to extend their body vertically after the session. Moreover, the ankle dorsiflexion angle at T3 increased after the
STS movement changes in CP following NDT
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
DOI: 10.3109/09638288.2014.972592
NDT session (Table 3), suggesting that the CP participants gained the ability to shift their weight from their forefoot to their heels while standing. Thus, the total duration of the STS movements was significantly less after the NDT session (Table 2). However, the STS movement changes may be due to the initial position of the ankle joint, before the intervention, being significantly different from that after the intervention (Table 3). In other words, the increased ankle dorsiflexion angle at T1, after the NDT session, might have led each CP participant to perform the STS movement without some atypical movement patterns. This was addressed in a study by Park et al. [27] that investigated the use of ankle foot orthoses (AFOs) on STS movements in children with CP. Their study demonstrated that the proximal compensatory strategy of the increased pelvic tilt and hip flexion did not change despite increased initial ankle dorsiflexion resulting from the use of AFOs. Thus, movements in CP patients might be affected by strong, atypical compensatory patterns rather than by the initial position of the ankle joint. Improved alignment and/or equilibrium reactions and body coordination could, therefore, be assumed to improve because the NDT session, contradicting the observations of Park et al. [27]. Therefore, facilitating more normalised movements instead of repeated atypical movement patterns is important for improving mobility in young children with CP. There were several limitations to this study. A major limitation was the lack of a control group undergoing a different intervention; the inclusion of such a group would have increased the possibility of detecting a learning effect caused by repeated STS movements instead of observing a real improvement caused by the NDT session. Moreover, we cannot present a reliability index, such as an intraclass correlation coefficient. Our data from the three trials differed since each participant could not always perform accurately, according to our instructions. This issue might be attributable to younger age of the participants and/or the longer measurement. Just like the small sample size, this limitation also restricts the generalisation of these findings. Furthermore, this study could not clarify how using upper limbs affects STS movements before and after the NDT session. By recruiting CP participants who can stand up without using a grip bar, a better understanding of STS movements would be obtained. Finally, the outcome measurement of this study was range of motion. Another outcome, such as electromyography, would provide a multilateral understanding of the effects of NDT on STS movements in children with CP. Recent investigations of lower limb strength training programs have demonstrated increased muscle strength in children with CP without evidence of increased spasticity or atypical movements [28–30]. To plan a more efficient therapeutic program, further studies involving a different study design and a larger number of participants is needed. To some extent, our findings support the hypothesis that a single NDT session can enable preschool-aged children with CP to stand using proper body mechanics. That is, after the NDT session, STS movements were more efficient in terms of selective muscle control. However, this study only showed the immediate effect of NDT, without assessing the long-term effects of NDT. Although the NDT session inhibited atypical movement patterns, this study demonstrated that the ankle joints angles, after the session, remained drastically smaller than those of the normal control children (Table 3 and Figure 4D). In this sense, increasing ankle dorsiflexion during STS might facilitate children with CP developing more coordinated STS movements. Park et al. [31] investigated the effects of BTA injection into the gastrocnemius muscle on STS movements in children with CP. That study suggested that a large reduction in spasticity could increase the ankle dorsiflexion angle and decrease the trunk forward tilt and
7
hip flexion angles. Thus, combining NDT with BTA injections is worth considering for children with CP, as this combination may enhance carryover in the STS movements. Maintaining these improvements might lead preschool-aged children with spastic diplegia CP to develop improved mobility, which would enhance their ADL and social participation.
Conclusions This study demonstrated that a single NDT session can improve STS movements by allowing the use of forward shank tilting in CP participants, without increasing the trunk forward tilt. After the subject’s hips were off the seat, the hip and knee joints locked together to balance the STS movements. Finally, the CP participants could extend their body vertically, without increasing ankle plantarflexion, while standing. These findings indicate that a single NDT session enabled preschool-aged children with spastic diplegia CP to stand from a seated position without using some of their atypical compensatory movement patterns immediately after the NDT session. Although this study could not examine the long-term effects of NDT, this information is invaluable for therapists planning NDT therapeutic programs for children with CP.
Declaration of interest The authors report no conflicts of interest. This study was supported by a Grant-in-Aid for Young Scientists (B) from the Japan Society for the Promotion of Science (23700618).
References 1. Wang T-H, Liao H-F, Peng Y-C. Reliability and validity of the fiverepetition sit-to-stand test for children with cerebral palsy. Clin Rehabil 2012;26:664–71. 2. Chrysagis N, Skordilis E, Koutsouki D. Validity and clinical utility of functional assessments in children with cerebral palsy. Arch Phys Med Rehab 2014;95:369–74. 3. Bobath K. Neurophysiological basis for the treatment of cerebral palsy. London: Mac Keith Press; 1991. 4. Park ES, Park CI, Lee HJ, et al. The characteristics of sit-to-stand transfer in young children with spastic cerebral palsy based on kinematic and kinetic data. Gait Posture 2003;17:43–9. 5. Hennington G, Johnson J, Penrose J, et al. Effect of bench height on sit-to-stand in children without disabilities and children with cerebral palsy. Arch Phys Med Rehabil 2004;85:70–6. 6. Yonetsu R, Shimizu J, Surya J. The effect of physiotherapy on sit-tostand movements in a child with spastic diplegia. Disabil Rehabil 2010;32:598–605. 7. World Health Organization. International Classification of Functioning, Disability and Health. ICF. Geneva: WHO Publishing; 2001. 8. Butler C, Darrah J. Effects of neurodevelopmental treatment (NDT) for cerebral palsy: an AACPDM evidence report. Dev Med Child Neurol 2001;43:778–90. 9. Raine S, Meadows L, Lynch-Ellerington M. Bobath concept: theory and clinical practice in neurological rehabilitation. London: WileyBlackwell; 2009. 10. Tsorlakis N, Evaggelinou C, Grouios G, Tsorbatzoudis C. Effect of intensive neurodevelopmental treatment in gross motor function of children with cerebral palsy. Dev Med Child Neurol 2004;46: 740–5. 11. Ketelaar M, Vermeer A, Hart H, et al. Effects of a functional therapy program on motor abilities of children with cerebral palsy. Phys Ther 2001;81:1534–45. 12. Adams M, Chandler L, Schulmann K. Gait change in children with cerebral palsy following a neurodevelopmental treatment course. Pediatr Phys Ther 2000;12:114–20. 13. Trahan J, Malouin F. Changes in the gross motor function measure in children with different types of cerebral palsy: an eight-month follow-up study. Pediatr Phys Ther 1999;11:12–17.
Disabil Rehabil Downloaded from informahealthcare.com by Mcgill University on 11/24/14 For personal use only.
8
R. Yonetsu et al.
14. Bower E, Mclellan D. Assessing motor-skill acquisition in four centres for the treatment of children with cerebral palsy. Dev Med Child Neurol 1994;36:902–9. 15. Palmer FB, Shapiro BK, Wachtel RC, et al. The effects of physical therapy on cerebral palsy: a controlled trial in infants with spastic diplegia. N Engl J Med 1988;318:803–8. 16. Embery D, Yates L, Mott D. Effects of neurodevelopmental treatment and orthoses on knee flexion during gait: a single-subject design. Phys Ther 1990;70:626–37. 17. Laskas C, Mullen S, Nelson D, Willson-Broyles M. Enhancement of two motor functions of the lower extremity in a child with cerebral palsy. Phys Ther 1985;65:11–16. 18. Jonsdottir J, Fetter L, Kluzik J. Effects of physical therapy on postural control in children with cerebral palsy. Pediatr Phys Ther 1997;9:68–75. 19. Bohannon RW, Smith MB. Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther 1987;67: 206–7. 20. Palisano RJ, Rosenbaum P, Bartlett D, Livingston MH. Content validity of the expanded and revised Gross Motor Function Classification System. Dev Med Child Neurol 2008;50: 744–50. 21. Roy G, Nadeau S, Gravel D, et al. The effect of foot position and chair height on the asymmetry of vertical forces during sit-to-stand and stand-to-sit tasks in individuals with hemiparesis. Clin Biomech (Bristol, Avon) 2006;21:585–93. 22. Camargos AC, Rodrigues-de-Paula-Goulart F, Teixeira-Salmela LF. The effects of foot position on the performance of the sit-to-stand
Disabil Rehabil, Early Online: 1–8
23. 24. 25. 26. 27. 28. 29. 30.
31.
movement with chronic stroke subjects. Arch Phys Med Rehabil 2009;90:314–19. Tully EA, Fotoohabadi MR, Galea MP. Sagittal spine and lower limb movement during sit-to-stand in healthy young subjects. Gait Posture 2005;19:338–45. Cohen J. A power primer. Psychol Bull 1992;11:155–9. Riley PO, Schneckman ML, Mann RW, Hodge WA. Mechanics of a constrained chair-rise. J Biomech 1991;24:77–85. Rodosky MW, Andriacchi TP, Andersson GB. The influence of chair height on lower limb mechanics during rising. J Orthop Res 1989;7: 266–71. Park ES, Park CI, Chang HJ, et al. The effect of hinged ankle-foot orthoses on sit-to-stand transfer in children with spastic cerebral palsy. Arch Phys Med Rehabil 2004;85:2053–7. Dodd KJ, Taylor NF, Damiano DL. A systematic review of the effectiveness of strength-training programs for people with cerebral palsy. Arch Phys Med Rehabil 2002;83:1157–64. Fowler EG, Ho TW, Nwigwe AI, Dorey FJ. The effect of quadriceps femoris muscle strengthening exercises on spasticity in children with cerebral palsy. Phys Ther 2001;81:1215–23. Liao HF, Gan SM, Lin KH, Lin JJ. Effects of weight resistance on the temporal parameters and electromyography of sit-to-stand movements in children with and without cerebral palsy. Am J Phys Med Rehabil 2010;89:99–106. Park ES, Park CI, Chang HC, et al. The effect of botulinum toxin type A injection into the gastrocnemius muscle on sit-to-stand transfer in children with spastic diplegic cerebral palsy. Clin Rehabil 2006;20:668–74.
