Comparative Efficacy of Medical Rehabilitation Methods in Children with Spastic Diplegia: Multichannel Myostimulation and Hydro-Kinesiotherapy in a Resort Setting

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RATIONALE Introduction Cerebral palsy (CP), which occupies a leading position in the structure of childhood neurological disabilities, is a significant medical and social problem. According to the Ministry of Health of Russia (2022), the prevalence of CP in the country reaches 2.4-3.1 cases per 1000 children, while spastic diplegia is diagnosed in 35-40% of patients [1]. The socio-economic burden of the disease remains high: according to estimates of the Research Institute of Rehabilitation, the annual costs of rehabilitation of one child with CP are 1.2-1.8 million rubles, and the total lifetime costs exceed 25 million rubles [2]. Despite the widespread use of spa treatment (SRT), including balneotherapy, peloidotherapy and massage, its effectiveness in spastic diplegia requires optimization through combination with modern rehabilitation methods [3]. A systematic review by Santos et al. (2022) confirmed that hydrokinesiotherapy improves motor function in children with CP, but most studies included heterogeneous groups (hemiplegia, tetraplegia), which limits the extrapolation of results to spastic diplegia [4]. A randomized clinical trial evaluating the Halliwick method demonstrated a positive effect of aquatic therapy on balance, but did not take into account long-term effects [5]. Similar limitations are characteristic of studies of multichannel myostimulation (NMES): a meta-analysis by Kwon et al. (2021) revealed an improvement in mobility, but long-term outcomes (>6 months) remain unexplored, and variability in stimulation parameters (frequency, duration) makes it difficult to form universal recommendations [6-8]. A critical drawback of many studies is the small sample size (<30 participants) and the lack of stratification by CP severity, which reduces the reliability of the conclusions [9]. Unlike previous studies, this work focuses exclusively on spastic diplegia (GMFCS I-III), excluding patients with severe forms (GMFCS IV-V), which minimizes the impact of population heterogeneity. The novelty of the study lies in the comprehensive assessment of both short-term (21 days) and long-term (6 months) effects of combinations of SCL with hydrokinesiotherapy, myostimulation, vibration therapy and exercise therapy with weights. For the first time, objective instrumental methods (stabilometry, electromyography) were used within a single protocol along with clinical scales (Ashworth, GMFM), which increases the validity of the results. OBJECTIVE To compare the effectiveness of the selected rehabilitation methods in children aged 8-13 years with spastic diplegia, paying special attention to the sustainability of the achieved improvements.

METHODS Study design A prospective interventional cohort, single-center, selective, controlled, randomized study was conducted at the state sanatorium of the Republic of Crimea "Sanatorium for children and children with parents "Chaika" named after Gelilovich" in accordance with the protocol reviewed and approved by the bioethics committee. Conclusion of the Bioethics Commission of the State Budgetary Healthcare Institution of the Republic of Karelia “Research Institute of Children's Balneology, Physiotherapy and Medical Rehabilitation” dated 12/14/2022, No. 7. The participants were divided into five groups: the main group (basic spa treatment (BST) + hydrokinesiotherapy, n=45), comparison groups (BST + multichannel myostimulation, n=30; BST + vibration therapy, n=30; BST + exercise therapy with weighting, n=30) and the control group (BST, n=50). The distribution was carried out by random accessibility depending on the availability of free places for the procedures. Eligibility criteria Inclusion criteria: Children aged 8–13 years with spastic diplegia (GMFCS I-III). Exclusion criteria: GMFCS IV-V; Severe cognitive impairment, epilepsy with uncontrolled seizures; Acute infections, decompensated somatic diseases; Contraindications to procedures (skin pathologies, metal implants, pacemakers); Botulinum toxin therapy or surgical interventions in the previous 6 months. Conditions of the procedure State Budgetary Institution of the Republic of Crimea "SDDR "Chaika" named after Gelilovich" Basic SCL: Balneotherapy: Sodium chloride baths (concentration 5-10 g / l, temperature 35-37 ° C, duration 8-12 minutes, course of 10-12 procedures); Peloidotherapy: Sulfide silt mud (temperature 37-38 ° C, applications to [specify zones], duration 10-15 minutes, course of 10 procedures); Standard physiotherapy and massage procedures. Hydrokinesiotherapy: 30-minute sessions (3 times a week) in a pool (depth 1.2–1.5 m, temperature 34–36°C); Exercises: active (swimming with boards, walking in water) and passive (stretching with an instructor); Use of equipment: noodles, weights (1–3% of body weight). Multichannel myostimulation: VY-1000 device (frequency 10–150 Hz), electrodes are applied to the motor points m. tibialis anteriot and m. gastrocnemius lateralis 20–30-minute sessions (2–3 times a week, course of 10–20 procedures). Vibration therapy: VMP-1 device (frequency 50 Hz, amplitude 2–4 mm); Local impact on the antagonist muscles of spastic zones (3-5 minutes per zone, a course of 10-15 procedures). Exercise therapy with weights: Weights (1-5% of body weight), exercises for the lower and upper extremities (squats, toe raises, dumbbell curls); Session duration: 25-30 minutes (3-4 times a week, a course of 12-15 procedures). Primary outcome of the study Reduction in spasticity: Assessment according to the modified Ashworth scale (all muscle groups of the legs, neurologist); Dynamics of motor functions: GMFM (Gross Motor Function Measure) scale. Additional outcomes of the study Muscle strength: Modified MRC (Medical Research Council) scale; Balance: Pediatric Balance Scale (PBS) - 14 tasks, including standing on one leg, 360° turns, stability assessment; Stabilometry: Parameters of the speed and area of ​​oscillations of the center of pressure (the MBN-Stabilo device); Electromyography: Surface EMG (the Neuro-MEP device) at rest and during voluntary movements; Everyday adaptation: Questionnaires for assessing daily activity. Main group (n=45): SCL + hydrokinesiotherapy; Comparison group A (n=30): SCL + multichannel myostimulation; Comparison group B (n=30): SCL + vibration therapy; Comparison group D (n=30): SCL + exercise therapy with weighting; Control group (n=50): only SCL. Criteria for forming groups: All participants met uniform inclusion criteria (age 8–13 years, spastic diplegia, GMFCS I-III); Distribution into groups was carried out based on the availability of procedures in the sanatorium, without randomization; The groups were comparable in terms of baseline characteristics: age (mean 10 years), gender (m/f ratio 1:1), initial degree of spasticity (Ashworth scale: 2.8±0.6 points) and level of motor functions (GMFCS I: 40%, II: 35%, III: 25%). The comparative analysis was aimed at assessing: Differences in the dynamics of spasticity (Ashworth scale) and motor functions (GMFM, PBS) between all groups on the 21st day and after 6 months; Relative effectiveness of each rehabilitation method compared to the control (SKL); Relationships between the type of intervention and objective instrumental indicators (stabilometry, EMG). Methods of recording outcomes The assessment was carried out twice: on the 1st and 21st days. Ethical review The study was approved by the Ethics Committee of the State Budgetary Healthcare Institution of the Republic of Karelia “Research Institute of Cardiology and Radiology” (Study Protocol No. 21 dated December 14, 2022). Informed consent was obtained from parents/guardians of all participants. Statistical analysis The sample size was not pre-calculated. The data were processed in IBM SPSS Statistics 27.0. The normality of the distribution was tested by the Shapiro-Wilk test. For parametric data, the paired t-test and ANOVA with the Bonferroni correction were used, for non-parametric.

The dynamics after the course of treatment for the corresponding groups are presented in Table 2 (Table 2) Table 2. Absolute values ​​and effect size (Cohen’s d) after rehabilitation (M ± SD)

Table 2. Absolute values and effect size (Cohen's d) after rehabilitation (M ± SD)

Comparative analysis of the effectiveness of the rehabilitation methods revealed statistically significant differences between the groups. The greatest reduction in spasticity according to the Ashworth scale was recorded in group 2 (multichannel myostimulation): Δ= -25% (p<0.001, d=0.68), while in **group 1 (hydrokinesiotherapy)** the improvement was Δ= -15% (p=0.003, d=0.51). The control group showed minimal changes (Δ= -5%, p>0.05). According to the GMFM scale, the maximum increase in motor functions was noted in group 2 (Δ= +22%, p=0.002, d=0.89), which exceeds the results of other groups (group 1: Δ= +18%, p=0.001; group 4: Δ= +13%, p=0.018). The dynamics of balance (PBS) was most pronounced in group 1 (Δ= +8.2 points, p=0.004), while in group 3 (vibration therapy) a deterioration was recorded (Δ= -0.49, p=0.062). The conducted analysis of EMG data (Table 3) revealed significant differences in the effectiveness of rehabilitation methods. The greatest improvement in integrated electromyographic activity (iEMG) was observed in the groups receiving hydrokinesiotherapy and multichannel myostimulation. In these groups, a statistically significant increase in iEMG was recorded for both agonist muscles (Tibialis anterior) and synergist muscles (Gastrocnemius lateralis), indicating increased neuromuscular activation and decreased functional asymmetry. Table 3. EMG indices before and after rehabilitation (M ± SD)

Table 3: EMG parameters before and after rehabilitation (M ± SD)

 Group 1 (hydrokinesiotherapy) demonstrated a uniform improvement in the activity of both limbs, which is consistent with the hypothesis of the symmetrizing effect of the aquatic environment on muscle tone. Group 2 (myostimulation) showed the most pronounced increase in iEMG, especially in the proximal sections, which may be associated with stimulation of spinal motor neurons and increased intermuscular coordination. In groups 3 (vibration therapy) and 4 (physical therapy with weights), iEMG changes were moderate, with the original asymmetry preserved, indicating a local rather than systemic effect of these methods. The control group (SKL) confirmed the limited potential of isolated basic therapy, which emphasizes the need for a combination with active rehabilitation methods. Table 4. Dynamics of stabilometric indicators (M ± SD) Table 4. Dynamics of stabilometric indices (M ± SD)

In the subgroups of patients with GMFCS II (n=72), a direct correlation was found between the decrease in spasticity (Ashworth) and the improvement of stabilometric parameters (Table 4): a decrease in asymmetry (IA) by 18–27% (p<0.05) and the center of pressure path length (SPL) by 11–25% (p<0.01). In **group 2**, in patients with initial asymmetry >10% (n=12), a decrease in the mediolateral shift of the center of pressure (MCoCx) by 25% (p<0.001) was noted, which is twice the average values ​​for the group. **hydrokinesiotherapy** is characterized by a selective improvement in anterior-posterior control (MCoCy: Δ= -15%, p=0.002), but no effect on balance variability (SDx/SDy: p>0.05). During the study, no adverse events related to the use of rehabilitation methods were registered. There were no cases of injuries, exacerbation of spasticity, skin reactions to electrodes or deterioration of neurological status. All participants completed the course of treatment in full. DISCUSSION This study demonstrated that the combination of basic spa treatment (BST) with hardware physiotherapy methods (hydrokinesiotherapy, multichannel myostimulation) and exercise therapy with weighting significantly improves motor functions, reduces spasticity and corrects postural disorders in children aged 8–13 years with spastic diplegia (GMFCS I–III). The most effective treatment was multichannel myostimulation (group 2), which showed a 25% decrease in spasticity according to the Ashworth scale (d=0.68, p<0.001), an improvement in motor functions (GMFM: Δ+22%, d=0.89) and a decrease in load asymmetry (IA: -27%, p<0.001). Hydrokinesiotherapy (group 1) also had a positive effect, especially on balance (PBS: Δ+8.2 points, p=0.004), while vibration therapy (group 3) and exercise therapy with weights (group 4) demonstrated limited effects, and in some parameters, negative dynamics (PBS: d=-0.49). The results of group 2 are consistent with the meta-analysis of Kwon et al. (2021), where stimulation of the antagonist muscles (m. tibialis anterior and m. gastrocnemius lat.) with a frequency of 30–50 Hz increased neuromuscular synchronization due to the activation of fast motor units. A decrease in IA asymmetry from -9.79% to -4.96% (p=0.045) confirms the hypothesis of a bilateral effect of the method described by Sheikh et al. (2020). A 25% reduction in the center of pressure path length (SPL) (from 159.54 to 119.66 cm) correlated with improved postural control, which is critical for preventing falls in children with diplegia The moderate improvement in balance (PBS: d=0.07) and reduction in spasticity (Ashworth: d=0.51) are partly consistent with the findings of the Halliwick study (Becker et al., 2021), where the aquatic environment facilitated movement due to hydrostatic pressure. However, the lack of significant changes in load asymmetry (+3.05% → +1.20%, p=0.210) suggests the need to supplement the method with orthotics or biofeedback. The ineffectiveness of vibration therapy (group 3) can be explained by suboptimal parameters: high frequency (50 Hz) increased proprioceptive imbalance, which led to an increase in SDx variability (p = 0.41). For comparison, Park et al. (2019) noted a positive effect at a frequency of 20-30 Hz. Physical therapy with weights (group 4) improved muscle strength (MRC: d = 0.62, p = 0.0003), but did not affect spasticity, which is consistent with the findings of Santos et al. (2022) on the need to combine strength training with neurounloading methods. Control group: Minimal changes (SPL: -5%, PBS: +2.4 points) confirm that basic SCL is not enough to correct movement disorders, but can serve as a platform for additional interventions. Clinical interpretation of effect sizes GMFM in group 2 (d=0.89) — corresponds to a clinically significant improvement, even with borderline significance of asymmetry (p=0.045). Decreased spasticity in groups 1–2 (d=0.51–0.68) — requires supplementation with balance correction methods. Worsening of PBS in group 3 — indicates the risks of non-adapted vibration therapy. Limitations of the study: Lack of randomization resulted in baseline differences between groups (e.g. IA asymmetry in group 2: -9.79% vs. group 1: +3.05%). Short-term follow-up (21 days) does not allow assessing the sustainability of effects. Subjectivity of the Ashworth scale, despite blinding of assessors. Bonferroni correction reduced the power to detect small effects (e.g. group 4: PBS, p=0.071). High variability in baseline data (e.g. SDx=0.53 cm) limited interpretation of changes. Results are only applicable to children with GMFCS I–III. Adapted protocols are required for patients with severe cognitive impairment or GMFCS IV–V.

CONCLUSION Systematic studies in recent years, including meta-analyses by kwon et al. (2021) and sheikh et al. (2020), have confirmed the effectiveness of neuromuscular electrical stimulation (NMES) and hydrotherapy in improving motor functions and reducing spasticity in children with cerebral palsy. However, issues of long-term sustainability of effects, optimization of intervention parameters (e.g., muscle stimulation frequency, water temperature), and adaptation of methods for patients with severe forms of the disease (GMFCS IV–V) remain unresolved. The present study contributes to solving these problems by demonstrating that the combination of basic NMES with multichannel muscle stimulation provides a clinically significant reduction in spasticity (δashworth = -25%, d = 0.68) and load asymmetry (δia = -27%, p < 0.001), and hydrokinesiotherapy improves balance (δpbs = +8.2 points) due to hydrodynamic unloading. Vibration therapy and exercise therapy with weighting showed limited effectiveness, which emphasizes the need for a personalized approach. The obtained results justify the inclusion of nmes and hydrotherapy in clinical guidelines for children with spastic diplegia, as well as the advisability of further studies to optimize stimulation parameters and assess long-term outcomes. The scientific value of the work lies in the comprehensive analysis of instrumental and clinical indicators, which creates the basis for developing algorithms for choosing rehabilitation methods based on the initial neuroorthopedic status of the patient.additional information

About the authors

Ernest A. Osmanov

Author for correspondence.
Email: spaun55@mail.ru
ORCID iD: 0000-0003-3022-0269
SPIN-code: 1038-7777

MD, Cand. Sci. (Medicine)

References

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