target="_blank" rel="nofollow" href="#ulink_f1e0cad2-df03-53c1-907c-599ed7a89469">114, 133, 134] when the appropriate technique and technology is selected and applied.
Fig. 6. Kinetic action of SWT on cells [77]. Shearing force from SWT (a) causes excuviation and excursion of cargo rich microvesicles (b), ensued by endosomal activation of toll-like receptors triggering modulation of macrophages, interleukins etc (c). These proceses are seen to engender progenesis effects (ie. angiogenesis), and the ensuing cascade of metabolic activities involving tissue regeneration [28, 35, 49–70, 87–90, 94–99]. Note: Image with permission of NonVasiv GmbH.
The Future of SW Medicine
We can usually tell the future by examining the past; over the past 3 decades, the history of medical SWT has revealed that its safety and efficacy in each area of its utility has encouraged further research for its expansion, while remaining intransigent to becoming demoded. There is growing evidence that SWT is influencing the activation and differentiation of endogenous stem cells, and is stimulating more research in this area. Among such investigations are: the utility of the evolution FlashWaveTM technology for musculogenesis via endogenous skeletal muscle stem cell activation and differentiation, presently being investigated by Vincent et al. [71, 72] to determine the efficacy for skeletal muscle regeneration in the aging population (sarcopenia/dynapenia), and to improved skeletal muscle resilience in the athletic population. Holfeld et al. [65] are presently investigating intracorporeal SWT on the heart (Fig. 7a, b) ushering in an interesting era in SW medicine.
In urology where SW were first utilized (ESWL) as a destructive force, SWT is now utilized as a regenerative and restorative modality redefining andrology, addressing the issue of erectile dysfunction and is showing very promising results [53–59]. Other investigations include the utility of SWT in dystonia and spasticity [135–140], diabetic neuropathy [141, 142], knee osteoarthritis [143–145], low back pain syndromes [146], uterine fibroids [147], and possible intervention in Langerhans islet beta-cell regeneration in type-1 diabetes mellitus [148], among other emerging indications. The potential clinical utility of SWT is vast and more vigorous research, clinical exploration and collaboration is required to provide firm support for its use and to receive the recognition and funding from both the public and private healthcare sectors.
Fig. 7. a Intracorporeal shockwave (SW) treatment of the heart: Holfeld et al. [64], Dept. of Cardiac Surgery, Innsbruck Medical University, Austria. b Specialised intracorporeal SW (electrohydraulic) applicator designed for open heart interventions.
Conclusion
With over 3 decades of utility since its inception into medicine, SWT has continued to extend its utility over multiple disciplines and has continued to be widely investigated by researchers globally. No two devices will produce the exact same stimulus, and this fact will have an influence and impact on clinical efficacy and outcomes. Therefore, the selection of appropriate technology, and the employment of effective assessment and application techniques is a pertinent fact for clinical success. The safety, noninvasive nature, and systemic neutrality of SWT makes it a unique interventional modality, and the expansion of its utility may provide a more sanative approach for the management of multiple pathologies. The increased utility of SWT has the potential to improve the quality of life and productivity across the lifespan, while reducing the burdens of global healthcare costs.
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