Cerebral Palsy (CP) is one of the primary causes of movement and posture disorders in children, affecting roughly 2-3 out of every 1000 children. Children diagnosed with CP often exhibit spasticity, suboptimal motor control, poor body balance as well as weak muscles.
Studies have demonstrated the efficacy of whole-body vibration therapy (VT), or Vibrotherapy, on whole-body vibrating platforms in improving mobility, muscle, and bone strength; however, optimal therapeutic protocols remain unknown.
Benefits
Cerebral Palsy (CP) is a group of nonprogressive motor disorders caused by static lesions in the developing and neonate brain that impair movement, posture, balance and coordination resulting in impairment. It is one of the leading causes of childhood physical disabilities and significantly diminishes quality of life for children affected by CP as well as their families.
There are various treatment approaches available, but most centers around rehabilitation and physiotherapy. With increasing interest in vibration therapy as an additional therapeutic intervention to support rehabilitation and restore normal muscle function, vibration therapy has proven its worth in improving spasticity, muscle strength and coordination while positively impacting bone mineral density.
In this systematic review and meta-analysis, we investigated both short and long-term effects of combined WBV with conventional physiotherapy on children with cerebral palsy (CP). Randomized controlled trials with side-alternating WBV protocols that vary in frequency and treatment duration versus conventional physiotherapy as a control were included for analysis using random-effects models to calculate weighted mean differences and 95% confidence intervals as well as publication bias indicators using funnel plots.
The results of the review indicate that WBV therapy can safely be integrated into physiotherapy to address musculoskeletal system issues in CP patients and increase functional independence; however, further confirmation must be sought with larger trials.
Multiple studies demonstrated the benefits of WBV on spasticity, an unpleasant symptom associated with cerebral palsy (CP), which can significantly limit mobility. One such comparison compared a gradually increasing 7-18 Hz VT protocol with one that used static 11Hz frequencies; results of that comparison showed the gradual approach was more successful at decreasing spasticity than its static counterpart.
Results from most studies demonstrated that WBV improved muscle strength and coordination for those suffering from cerebral palsy (CP). While most studies reported long-term improvements, some indicated temporary effects. Furthermore, most of these studies focused on hemiplegic participants while only two included tetraplegic participants; therefore further investigation must take place to ascertain its efficacy with more severe forms of cerebral palsy.
Methods
Recent years have witnessed a dramatic surge in vibration therapy among patients with cerebral palsy. Studies have demonstrated its benefits, such as relieving spasticity and muscle tension while increasing bone mineral density and relieving tension. Early research on its benefits has been promising; however, more high-quality studies are necessary to establish its efficacy.
A systematic review was conducted to assess the effects of whole body vibration on mobility and other health outcomes in people living with cerebral palsy (CP). It included randomized controlled trials, cohort studies, case-control studies, pre-post studies, single subject designs and single subject designs. For inclusion, several criteria had to be met: 1) human participants diagnosed with CP; 2) intervention used whole body vibration; and 3) publication in peer reviewed journals. Thirty one articles met these eligibility criteria and 12 duplicates were removed before proceeding further with review; remaining articles varied in quality but five were considered of acceptable quality by expert reviewers.
Vibration therapy appears to be safe for most individuals, including children. A physician or physical therapist should conduct a comprehensive examination and screening before beginning vibration exercises, including reviewing health history, medications being taken and any known allergies or aversions to exercise. Furthermore, pregnant women or those with metal implants such as joint replacements, pacemakers or an open wound should avoid performing vibration exercises as their bodies might react adversely.
Vibration therapy can be employed using several devices. One such is the Galileo, a vibration plate with frequencies between 5-30Hz that features side-alternating movement with variable speeds for individual treatment goals such as balance training, joint mobilisation, tight muscle activation and strengthening, spasticity reduction and strength and coordination development. Treatment sessions take 20 minutes daily three or four times each week and may be done either individually or as group therapy sessions.
Results
Studies have reported vibration therapy as an effective strategy for improving gross motor function, balance and muscle strength among children with cerebral palsy. Some research also indicates it reduces spasticity and increases bone density – although quality issues limit these studies due to small sample sizes and heterogeneous treatments – further studies are required to ascertain if these improvements can be replicated across larger samples and different subtypes of cerebral palsy.
One study involved randomizing children with spastic CP to conventional physiotherapy with or without whole-body vibration (WBV), while those who received subacute vibratory therapy (sVT) demonstrated more improvement in 10m walk times compared with those who didn’t; although, statistically speaking, no difference could be detected; additionally, this research did not utilize isokinetic dynamometers as means for measuring muscle strength which may hamper its ability to determine whether sVT increased muscle strength.
One study examined the impact of WBV on 10m walk times for children with GMFCS level I-IV cerebral palsy compared to those in a control group who did not receive sVT. They discovered that while it significantly improved 10m walk times for this group, it did not significantly alter walking speed for this control group. Unfortunately, however, their results could only be replicated within eight children, and could not be generalized across a larger sample population.
Studies of chronic pain (CP) often employ different physiotherapy protocols, making it hard to compare their respective effectiveness. Furthermore, each protocol utilizes various vibration amplitude settings which makes identifying one which stands out more challenging.
Researchers conducted one study comparing the effects of sVT and conventional physiotherapy for children with hemiplegic cerebral palsy. Participants in the sVT group performed sessions after every conventional physiotherapy session; it was found to increase gait speed while decreasing spasticity; additionally, those in this group received better proprioceptive feedback than others.
Furthermore, the sVT group demonstrated increased range of motion and faster gait speed compared to its control group counterpart. Therefore, its authors concluded that sVT may help increase mobility while decreasing spasticity among children with cerebral palsy, particularly those suffering from hemiplegia.
Conclusions
Many patients with cerebral palsy (CP) experience impaired upper extremity function, which interferes with their participation in educational activities, exploration of future vocational options, and ability to complete daily tasks [1,2]. Spasticity, balance deficits and diminished strength are common symptoms of CP which contributes to decreased quality of life for affected children and their caregivers alike; effective therapeutic protocols must therefore be created in order to enhance upper extremity function in these cases.
Vibration therapy (VT) is an emerging treatment strategy designed to decrease muscle tone, increase strength and improve movement capacity through sensory and sensorimotor adaptations. An emerging body of evidence suggests that vibration therapy (VT) can alleviate CP symptoms by directly impacting both nervous and musculoskeletal systems; its stimulation of monosynaptic and polysynaptic afferent pathways has shown to promote muscular health while stimulating monosynaptic and polysynaptic afferent pathways has caused positive responses which result in improvements to movement strength, balance, gait mobility as well as bone density.
Studies have demonstrated that one acute session of VT can effectively decrease reflex excitability, spasticity and coordination deficits. Furthermore, chronic use of VT leads to enhanced movement ability as measured by gross motor function (GMF), strength, gait mobility and enhanced bone mineral density for posture control.
Further research must be conducted in order to establish whether individualized vibration therapy protocols are more effective than standardized approaches and whether their benefits continue over time. It is also essential that researchers identify optimal frequency, amplitude and duration levels in order to produce clinically relevant effects; and assess any long-term implications VT might have on patients’ health.
AA, SG and JGBD developed the study and its concept. AA conducted assessments and treatments, managed the database, extracted data for analyses and performed analyses; while AA, SG and JGBD developed and critically revised the draft manuscript together. All authors have approved of its final version. This work was funded by European Commission FP7 Neuromuscular Rehabilitation project as well as Irish National Institute for Disability and Learning funding that enabled establishment of an integrated physiotherapy center of excellence for cerebral palsy patients in Ireland.
