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Table of Contents
ORIGINAL ARTICLE
Year : 2022  |  Volume : 4  |  Issue : 1  |  Page : 14-21

Prognosis in the functional status of children with duchenne muscular dystrophy with physiotherapy and yoga exercise protocols – A randomized controlled trial


Physiotherapy Center, National Institute of Mental Health and Neuro Sciences, Bengaluru, Karnataka, India

Date of Submission22-Jan-2022
Date of Decision27-May-2022
Date of Acceptance07-Jun-2022
Date of Web Publication30-Jul-2022

Correspondence Address:
Dr. Pradnya Dhargave
Physiotherapy Center, National Institute of Mental Health and Neuro Sciences, Bengaluru - 560 029, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijptr.ijptr_8_22

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  Abstract 


Context: Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disease leading to destruction of the skeletal muscles, causing limitations in the activities of daily living, and ambulation at a later stage.
Aims: The present study intended to identify the effect of add-on yoga with physiotherapy intervention compared to physiotherapy exercise program on the functional status of children with DMD.
Settings and Design: A randomized controlled study was conducted at the physiotherapy center of a tertiary care hospital.
Subjects and Methods: The study recruited 124 boys diagnosed with DMD who were randomly divided into two groups. Group I received home-based physiotherapy exercise program and was advised to perform twice daily for all days of the week. Group II was advised to perform physiotherapy and yoga at home. Functional status of the participants was assessed using muscular dystrophy functional rating scale (MDFRS) and timed functional test (TFT), taken at baseline, and on regular intervals of 3 months, up to 1 year.
Statistical Analysis Used: Repeated measures ANOVA, Fisher's least significant difference analysis, and t-test analysis were used for statistical analysis. P < 0.05 was considered statistically significant.
Results: Eighty-eight participants completed the entire study with 45 in Group I and 43 in Group II. Significant time effect was demonstrated in both the groups for MDFRS (P < 0.05) and TFT (P < 0.01) measures, demonstrating beneficial effects of treatment protocols of both groups.
Conclusions: The study identified that the combined yoga and physiotherapy interventions were as effective as physiotherapy alone.

Keywords: Duchenne muscular dystrophy, Functional status, Home exercise program, Physiotherapy, Yoga


How to cite this article:
Dhargave P, Sendhilkumar R, James TT. Prognosis in the functional status of children with duchenne muscular dystrophy with physiotherapy and yoga exercise protocols – A randomized controlled trial. Indian J Phys Ther Res 2022;4:14-21

How to cite this URL:
Dhargave P, Sendhilkumar R, James TT. Prognosis in the functional status of children with duchenne muscular dystrophy with physiotherapy and yoga exercise protocols – A randomized controlled trial. Indian J Phys Ther Res [serial online] 2022 [cited 2022 Nov 27];4:14-21. Available from: https://www.ijptr.org/text.asp?2022/4/1/14/353010




  Introduction Top


Duchenne muscular dystrophy (DMD) is a progressive primary muscle disorder with an X-linked recessive pattern of inheritance.[1],[2] It is considered to occur by the mutation in the dystrophin gene at locus Xp21.[3],[4] Cell death occurs with an increased oxidative stress placed by the excess calcium which penetrates the cell membrane due to the absence of dystrophin.[5],[6] DMD accounts for 30% of the muscular dystrophies reported in India.[7] Children demonstrate limitations in the range of movement at the age of 5 years, progressing to a difficulty in activity of daily living (ADL). Assistance in ambulation is usually required by the age of nine.[8] Secondary respiratory complications as well as scoliosis and contractures develop with the use of wheelchair in the later stages.

Functional status has been defined as “an individual's ability to perform normal daily activities that are essential to meet basic needs, fulfill usual roles, and maintain health and well-being.”[9] This can be further explained with two concepts; the functional capacity which reflects the maximum capacity of the individual for performing ADL, and functional performance which reflects the activities performed by an individual in a day-to-day life.[10] Health perceptions, mood, physiological and biological impairments, or symptoms can influence the functional status of an individual.[9] Other factors include a reduction in muscle strength as well as cardiovascular endurance.

Physical therapy is found to be an essential therapeutic interventions in those with impaired mobility.[11] Studies have identified a superior effect of physiotherapy in disabled children.[12],[13] Physiotherapy interventions focus on maintaining the movement and prolonging the functional capacity, preventing deformities, and also in educating the family regarding the disease. Yoga is an ancient Indian science and a complementary mind-body therapy practiced globally, providing therapeutic benefits. Research has shown that the problem of disability can be taken care of by the practice of yoga, improving the motor control and performance.[14],[15] A clinical study on 46 children with DMD reported a reduction in creatine kinase levels and improved functional capacity in 40%–60% of the study population with ayurvedic Panchkarma and yoga interventions involving Pawanmuktasana and Bhastrika Pranayama.[16]

DMD is a progressive disease and as yet there is no cure for it. There is a demand to develop a comprehensive rehabilitation program focusing on the improvements in the functional capacity as well as the prevention and treatment of complications. There is a paucity of evidence suggesting an appropriate therapeutic protocol in DMD for the same. Moreover, if the regime of exercise is home based, it would be more cost-effective in implementation and thus, perhaps ensure better and longer participation from the patients' family. There is also lack of literature on the benefits of yoga on the clinical and functional parameters of DMD. Hence, this study was intended to see the efficacy of a home-based physiotherapy program and the combination of physiotherapy with yoga and their beneficial effects on the functional status in children with DMD.


  Subjects and Methods Top


The present study was primarily conducted in the physiotherapy section of a tertiary care hospital. Children from the outpatient department confirmed genetically and/or immunohistochemically to have DMD and those who met all the study criteria were recruited into the study. The inclusion criteria include those who are between the ages of 5–10 years and could able to walk independently or with minimal assistance. Muscular dystrophies other than DMD, nonambulant children, those who are already undergoing yoga and physiotherapy, those who were on steroids for more than 3 months, and those with associated cardiopulmonary symptoms were excluded. The CONSORT flow diagram is illustrated in [Figure 1]. The study was approved by the Institutional Ethics Committee. Written informed consent was obtained from the parents or guardians prior to the recruitment.
Figure 1: CONSORT Flow Diagram

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The sample size was calculated based on statistical requirements to achieve a power of 80% for the study design, in consideration with the previous studies within the same population.[17] The study recruited 124 boys who satisfy the study criteria. Each group had 62 participants and was assessed at baseline and every 3 months, for 1 year. At various timeframes of assessments, 36 children (29%) dropped out from the study (Group I: 17 (27.4%), Group II: 19 (30.6%). Eighty-eight boys (70.9%) completed all the five follow-up assessments.

The subjects were paired for age and randomly allocated to two groups by age-matched simple random sampling procedure using computer-generated Tippet's random number table. Sealed opaque envelopes were utilized for the concealment of allocation sequence. Group I received physiotherapy only whereas Group II received physiotherapy with yoga. The assessment and treatment were performed by the same researcher, hence were not blinded.

On the day of recruitment, the child was assessed for baseline parameters and was taught either physiotherapy exercises or yoga as per randomization [Table 1]. The detailed explanation of the protocol is available in our earlier studies.[18],[19] The physiotherapy exercises were taught by the expert physiotherapist and for teaching yoga, assistance was sought from an expert in yoga practice. The researcher got trained for more than 3 months in conducting the yoga program for children with DMD from a qualified yoga teacher with a Master's Degree in Yoga. The caregivers were also made to practice yoga/physiotherapy techniques to offer assistance during the physiotherapy or yoga when the child found it difficult to reach the desirable posture or the position. Frequent rest was given in between the periods of assessment, teaching, and supervision. The child and the caregivers were instructed to strictly follow the prescribed program at home daily. Each child was followed up for 1 year at intervals of 3 months. The functional status of children was assessed in baseline as well as at the time of follow-up using muscular dystrophy functional rating scale (MDFRS) and timed functional test (TFT).
Table 1: Physiotherapy and Yoga protocol

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MDFRS is a disease-specific measure of the functional status in for patients with muscular dystrophies, which is found to be both reliable and valid.[20] The four domains of MDFRS include mobility, basic activities of daily living (BADL), arm function, and impairment. The total MDFRS score indicating the score of all 4 domains ranges from 33 to 132 (132 being the highest score: Higher score = higher functional score).[20] For assessing TFT, the following activities were performed by the child and the time (in seconds) required to do these activities was recorded using a stopwatch; (1) standing from lying supine, (2) climbing 4 standard stairs, (3) walking 30 feet as fast as possible, (4) standing from sitting on a chair, (5) wearing a T-shirt, and (6) cutting out a 3 × 3 inch square of paper with scissors. TFT has found to be reliable in patients with DMD in assessing their functional improvement.[17] Both outcome tools were measured by a qualified physiotherapist holding a master's degree. All the tests were carried out with loose clothing and bare feet as described earlier.[17]

The child and caregivers in both the groups were taught home-based program during the supervised treatment sessions, which lasted for 1 week. Group I was advised to administer physiotherapy exercises twice daily for 45 min, and each exercise were carried out for ten times each on both the sides. Group II was advised to administer yoga for 45 min in the morning session and physiotherapy for 45 min in the afternoon. Standing and walking were done by both the groups for 1 h in one complete day with frequent rests in between. Participants were asked to do the exercises all the days of the week and were called for follow-up at every 3 months. They were also asked to maintain an exercise diary and to mention the time of each day when they have performed the exercises, which was counter-checked by parents. The diary was assessed at each follow-up to assess the compliance toward exercises.

The data analysis was performed by IBM SPSS statistics software version 20.0 (IBM Corp. Released 2011.IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp). Data were expressed as mean ± standard deviation for continuous variables, and in percentage for categorical variables. Repeated measures ANOVA were performed to compare the groups with different timeframes of assessment. The pairwise comparison was assessed by Fisher's least significant difference post hoc test. Independent t-test was performed to analyze the baseline values of both groups. Non-parametric data were analyzed using Mann–Whitney U-test. P < 0.05 was considered statistically significant.


  Results Top


Among the 124 boys recruited (mean age 7.9 ± 1.5 years), the mean weight was 20.6 ± 4.3 kg and height was 118.2 ± 8.4 cm. The demographic data of participants and baseline assessment of ambulation are depicted in [Table 2]. MDFRS and TFT tests were assessed at baseline and the groups were found to be homogeneous [Table 3].
Table 2: Demographic data of study population

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Table 3: Muscular Dystrophy Functional Rating Scale scores of two groups at various timeframes

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Comparing the baseline data in Group I, significant improvements were observed in the mobility (P = 0.039), BADL (P = 0.009), impairment domain (P = 0.020), and total MDFRS scores (P = 0.009), but failed to demonstrate a significant change in the arm function domain (P = 0.236). In Group II, only the mobility domain and total MDFRS scores demonstrated improvements from baseline to 1 year (P < 0.05) [Table 3]. The trend of changes in MDFRS within two groups across the timeframe is illustrated in [Figure 2].
Figure 2: Trend of changes in MDFRS within two groups across the timeframe. MDFRS: Muscular dystrophy functional rating scale

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In Group I, the time taken for climbing the stairs improved from baseline up to 1 year, wearing a “T” shirt and cutting a paper improved from baseline to 9 months, standing from sitting posture improved significantly from baseline to 6 months, standing from supine improved from 3 months up to 1 year and no significant change was noticed in the walking domain of TFT. In Group II, walking, standing from supine, and sitting showed significant improvement from baseline up to 1 year; wearing a t-shirt and cutting a paper from baseline to 9 months, and no significant change was noticed in climbing stairs domain of TFT [Table 4]. The trend of changes in TFT within two groups across the timeframe is illustrated in [Figure 3].
Figure 3: Trend of changes in TFT within two groups across the timeframe. TFT: Timed functional test

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Table 4: Timed functional test scores of two groups at various timeframes

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There was a significant time effect observed for all the components in the TFT between groups, but the significant interaction effect was reported only for standing from sitting (P = 0.027). There was a mean difference of −2.20 ± 0.70 s in Group I denoting a reduction in time to perform standing from sitting, whereas Group II showed an increase in the time taken at 12 months, with a mean difference of 0.50 ± 0.97 s. The results suggest a similar effect for both treatment protocols on the various domains of MDFRS and TFT scores, with an upper hand in few domains for the physiotherapy protocol provided to Group I.


  Discussion Top


In essence, DMD is progressive and has a limited prognosis with therapeutic interventions and also causes a reduction in life expectancy.[21],[22] Improved life expectancy with comprehensive therapeutic approaches warrants interventions focused on maintaining the strength of the muscles and functions in patients with DMD.[23],[24] This prospective randomized active control study is the first of its kind of intervention study, which compared the physiotherapy protocol in DMD to a combined physiotherapy and yoga to identify the changes in the functional status in individuals with DMD.

With progressing muscle weakness in DMD, functional ability eventually becomes impaired. Other factors include disuse atrophy or a reduction in functional muscle tissue, injury due to overuse of muscles or an increased fat deposit, presence of secondary cardiopulmonary and musculoskeletal complications including contractures, and increased energy requirements for activities. Psychosocial factors such as mood, depression, decreased motivation for activity, or an increased barriers within society can influence their functional ability.[25] Studies have reported increased dependence on activities such as stair climbing, bathing, and toileting.[26],[27],[28] All children in the current study had reduced mobility, BADL, arm function, impairment, and total MDFRS scores. All children had more difficulty with stair climbing, sitting from supine position and standing from sitting and less difficulty with rolling, transfers, and outdoor and indoor mobility. Many children in the study population had an intact capability for ambulation even with an advanced age making locomotion one of the easy tasks.

Physiotherapy has found to be effective in improving muscle strength, minimizing the progression of contractures and deformities, improving respiratory capacity, and also extends independent or assisted locomotion as much as possible.[21],[24] This study identified that although physiotherapy showed better improvement in more domains of MDFRS than combined yoga and physiotherapy protocol, there was no significant difference in the improvement noted between the two groups. At the end of 1 year, individuals who received physiotherapy was better in maintaining ambulation in almost all children than with yoga and physiotherapy combined. Improvements were also evident in functional activities with physiotherapy protocol than the combined therapy. The combined protocol of yoga and physiotherapy failed to demonstrate improvements in climbing activity even after 12 months of intervention.

Abranson and Rogoff conducted a study on 27 DMD children and found that physiotherapy had a positive result on strength, contracture, and mobility and the maximum improvement was noted within the first 8–10 weeks.[29] Vignos, in their study, could not identify an improvement in timed functional activity with physiotherapy.[30] However, with a good physiotherapy protocol, it is possible to minimize deformity and weakness in the early stages and keep the child erect and active for a prolonged period.

Regular practice of yoga is known to increase physical endurance and also helps in effectively coping with the emotional and physical stress by improving one's perception and consideration of the situations.[31] Yoga enhances physical health by improving the performance and control of motor activities, altering autonomic and metabolic functions, and improving the respiratory functions.[14],[15],[32] Several authors investigated the effect of yoga on physiological parameters and reported that yoga promotes physical health by improving performance.[15],[33],[34] It is difficult for a child with DMD to achieve all these steps and perform the practices with understating of the subtle aspects mentioned above. Hence, the expected benefits could match only those similar to any low-intensity physical activity but with the difference that yoga postures offer more spinal stretches, involve girdle muscles, and are maintained with effortlessness and repeated with least strain on the muscles and hence would be best suited for DMD children. The mechanism by which individuals demonstrated improvements in functional outcome can be hypothesized to an improved stability with exercises, which helps in reducing muscle hyperactivity and overloading, thus minimizing muscle damage.[35]

The limitations of the study include a higher dropout rate of 29%. Few parents were also reluctant to continue the treatment to explore alternative therapies. Other reasons identified for the lack of participation were monetary insufficiency, difficulty in long distances of travel to the hospital for follow-up, nonavailability of disabled-friendly public transport system, and the decision of parents in planning for another child leading to decrease in attention toward the child with DMD. Future studies can incorporate long-term home-based supervised interventional programs to increase the rate of participation and adherence to treatment protocols.


  Conclusion Top


Combination of yoga and physiotherapy protocol was as effective as physiotherapy interventions alone in children with DMD. Yoga can be incorporated into the rehabilitation of individuals with DMD to improve the functional status. Yoga can be considered for daily therapy routine to avoid boredom in children with DMD during exercise therapy.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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