Applied Research in Children With Spastic Cerebral Palsy in the Extracorporeal Shock Wave Therapy

Cerebral palsy (CP) is a clinical syndrome characterized by a persistent disorder of posture or movement caused by a non-progressive disorder of the immature brain. The prevalence of CP has been reported to be between 1.86 cases per 1,000 population in the United Kingdom and 3.6 cases per 1,000 in 8-year-old children in the United States, with little variation among Western nations. In a very recent systematic review analyzing a total of 49 studies, the pooled overall prevalence of CP was 2.11 cases per 1,000 live births. Rates of CP in population-based settings in India and China gave figures of 2-2.8 cases per 1,000 births. A systematic literature review for a period spanning between 1965 and 2004 found CP more prevalent in more deprived socio-economic populations. The same study identified low birthweight, intrauterine infections and multiple gestation as the most important risk factors for CP.

Most children with CP suffer from spasticity as the main motor disorder. Spasticity is a major challenge for rehabilitation of children with CP. This is because spasticity can cause pain, prevent or hamper function and may disturb sleep. Spasticity of plantar flexor muscles is a particular problem in CP because it causes toe walking. This can result in major functional implications such as disturbances in balance and walking, and interfere with gross motor function.

The management of spasticity in CP is complex and is a major challenge to the treatment team. The ultimate goal of any therapy program must be to achieve the child's maximum potential in motor skills. Unfortunately, the scientific evidence for various physical therapy treatment options for children with CP is limited. Botulinum neurotoxin (BoNT) is a widely used and effective pharmacological treatment for focal muscle over-activity. An alternative to BoNT treatment is focal intramuscular treatment with phenol and alcohol, with the aim to improve activity limitations and other outcomes in children and adults with spasticity. However, focal intramuscular injection of BoNT, phenol and alcohol is not without problems: (i) BoNT is expensive and not available in many countries; (ii) a significant risk of focal intramuscular injection of alcohol and phenol is persisting pain; and (iii) all these procedures are invasive and, thus, not without risk when applied under difficult hygienic conditions. With regard to post-stroke spasticity, a recent Cochrane review concluded that, at best, there was 'low level' evidence for the effectiveness of outpatient multidisciplinary rehabilitation in improving active function and impairments following BoNT treatment for upper limb spasticity in adults with chronic stroke.

Orthopedic surgery is considered a last resort in managing spasticity in children with CP, but is not an option for managing spasticity per se. Instead, it is used to help correct the secondary problems that occur with growth alongside spastic muscles and poor motion control. Those problems include muscle shortening, joints contractures and bony deformities.

Recently, extracorporeal shock wave therapy (ESWT) has become an alternative in the treatment of spasticity. A byproduct of extracorporeal shock wave lithotripsy, ESWT has emerged as a noninvasive management option for tendon and other pathologies of the musculoskeletal system with minimal unwanted side effects such as temporary skin redness and pain during treatment. Prior studies on tendinopathy showed that ESWT can be as or more effective than other forms of treatment such as eccentric exercise, traditional physiotherapy, steroid injections and surgery. There are two different types of extracorporeal shock waves - focused (fESWT) and radial (rESWT) - and several modes of operation of focused and radial extracorporeal shock wave generators.