Recent Advances in the Treatment of Spasticity: Extracorporeal Shock Wave Therapy

Abstract

Spasticity is a common sequala of the upper motor neuron lesions. For instance, it often occurs in the first 4 weeks after stroke and is seen in more than one-third of stroke survivors after 12 months. In recent years, extracorporeal shock wave therapy (ESWT) has been recognized as a safe and effective method for reducing muscle spasticity. Possible/relevant mechanisms include nitric oxide production, motor neuron excitability reduction, induction of neuromuscular transmission dysfunction, and direct effects on rheological properties. There are two types of ESWT, focused and radial, with the radial type more commonly applied for treating muscle spasticity. Concerning the optimal location for applying ESWT, the belly muscles and myotendinous junction seem to produce comparable results. The effects of ESWT on spasticity are known to last at least four to six weeks, while some studies report durations of up to 12 weeks. In this review, the authors will focus on the current evidence regarding the effectiveness of ESWT in spasticity, as well as certain technical parameters of ESWT, e.g., the intensity, frequency, location, and number of sessions. The pertinent literature has been reviewed, with an emphasis on post-stroke upper limbs, post-stroke lower limbs, cerebral palsy, and multiple sclerosis. In short, while ESWT has positive effects on parameters such as the modified Ashworth scale, mixed results have been reported regarding functional recovery. Of note, as botulinum toxin injection is one of the most popular and effective pharmacological methods for treating spasticity, studies comparing the effects of ESWT and botulinum toxin injections, and studies reporting the results of their combination, are also reviewed in this paper.

Effect of Botulinum Toxin Injection and Extracorporeal Shock Wave Therapy on Nerve Regeneration in Rats with Experimentally Induced Sciatic Nerve Injury

“…ESWT is a non-invasive treatment method used for musculoskeletal pain management using shock waves [8,9]. Recently, the application of ESWT has been expanded to nonmusculoskeletal diseases, such as complex regional pain syndrome, ischemic heart disease, diabetic foot ulcers, and peripheral nerve injuries [10][11][12][13]. ESWT has been proven to upregulate angiogenesis and growth factors through the activation of endothelial nitric oxide synthase and vascular endothelial growth factor [14,15].…”

The effect of extracorporeal shock wave therapy on large neurogenic heterotopic ossification in a patient with pontine hemorrhage: A case report and literature review

“…[ 20 ] Since the efficacy of ESWT on spasticity is achieved through the reduction of motor neuron excitability, it is expected that application to myotendinous junctions, where the Golgi tendon organ resides, will provide the best outcome. [ 22 ] However, in a previous study in which 151 patients were divided into 2 groups, 1 group with ESWT application to the belly muscle and the other to the myotendinous junction, the MAS and Modified Tardieu Scale of both groups decreased after ESWT application without significant difference. [ 23 ] Because the patient in our study had large HO on both hips, there was no remarkable change in spasticity.…”

Effect of extracorporeal shock wave therapy on spastic equinus foot in children with unilateral cerebral palsy

“…The mechanism behind reduced spasticity can be explained by the effect of rESWT on the secretion of nitric oxide, 28 the induction of mechanical vibration that acts on intrinsic muscular components and fibrosis, a reduction in spinal cord excitability, stimulation of the Golgi tendon organ, and muscle stiffness induced by the passivity of the muscles. 29 Nitric oxide secretion due to rESWT facilitates the formation of neuromuscular junctions. It plays a significant role in memory, central nervous system-related neural transmission, and impeded neuromuscular transmission with a subsequent decrease in spasticity.…”