Shock Wave Therapy for Wound Healing and Scar Treatment

AbstractShock Wave Therapy (SWT) meets all the requirements for the ideal non-invasive scar treatment. It is safe, well tolerated by patients, cost-effective, easy to apply, has low complication rates, and can be used in an outpatient setting. The overall effect of SWT is an improvement of tissue homeostasis, accompanied by an improvement of the tissue self-healing abilities, and it seems to focus on inducing tissue regeneration and matrix remodeling in vivo by means of mechanotransduction.SWT has a beneficial effect on wound healing and is characterized by an upregulation of the angio-active factors as nitric oxide (NO) and vascular endothelial growth factor (VEGF) leading to induced angiogenesis. A downregulation of alpha-SMA expression, myofibroblast phenotype, TGF-β1 expression, fibronectin, and collagen type I are measured after SWT on scars, leading to improvement of several relevant scar parameters like height, pliability, vascularity, and pigmentation, and thus ameliorating function.For a full treatment outline, the energy flux density (EFD), the number of pulses, the pulse frequency, and the number and interval of treatments are the most relevant parameters. The EFD for soft tissue indications is typically in the range of 0.08–0.25 mJ/mm2, while scars and fibrosis are treated with an EFD ranging between 0.15 and 0.33 mJ/mm2. These settings seem to be ideal to induce the optimal cell responses for each indication.All the presented findings are fundamental knowledge for further investigation of SWT to reduce the fibrous component in regenerating and remodeling tissues. However, the full potential of SWT in wound healing and scar treatment needs further unraveling.