Diabetic foot ulcer, pressure ulcer and venous stasis ulcer are the most common chronic skin and soft tissue wounds. A chronic wound is usually one that has failed to heal within three months.
Diagnosis is based on the clinical features of the disease. The incidence is approximately 1%, with chronic wounds mostly affecting people 60 years or older. Accordingly, the number of chronic wounds will rise as the population ages.
Factors that contribute to chronic wounds include poor circulation, (diabetic) neuropathy, bacterial colonization and infection, systemic illnesses, age, repeated trauma, vasculitis, immune suppression (including the use of steroids over a long period), but also emotional stress.
According to the University of Texas Wound Classification system, wounds are categorized into four stages (A: without infection and ischemia; B: with infection; C: with ischemia; D: with infection and ischemia) and four grades (0: pre- or postulcerative lesion completely epithelialized; 1: superficial wounds, not involving tendon, capsule or bone; 2: wounds penetrating to tendon or capsule; 3: wound penetrating to bone or joint). Wound healing is classically divided into four phases (i: hemostasis; ii: inflammation; iii: proliferation; iv: remodeling) with considerable overlapping among individual phases.
These phases are controlled by a wealth of growth factors that are involved in wound healing such as vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and transforming growth factors α and β (TGF-α and -β), to mention only a few. Inadequate levels of growth factors may also contribute to the formation of chronic wounds.
Therapeutic strategies for chronic wounds aim at preventing and treating infection, fighting ischemia, and replacing and/or stimulating growth factors. This can be achieved by surgical wound debridement, application of hyperbaric oxygen, negative pressure wound therapy, and topical and systemic application of molecules such as cell adhesion proteins, cytokines, enzymes, or EGF-like growth factor. Mesenchymal stem cell therapy has become another potential future target for intervention.
Recently radial shock wave therapy (RSWT) was introduced into the management of chronic wounds (Stages/Grades A1 and A2, as well as C1 and C2 with great care), based on its proven abilities to improve the functional microvasculature, stimulate expression of growth factors such as VEGF, and increase cell proliferation. RSWT is particularly interesting for those chronic wounds that are too small for negative pressure wound therapy.
Specific recommendations prior to RSWT |
Perform standard wound cleaning and debridement prior to RSWT
Place sterile plastic foil over the wound and surrounding tissue Apply sterile coupling gel onto the drape |
Specific recommendations after RSWT |
Remove gel and plastic foil, clean with sterile saline solution
Apply standard wound dressing according to the individual phase of wound healing |
Number of treatment sessions | 10 |
Interval between two sessions | 2 times a week |
Air pressure Evo Blue® | 2 to 4 bar |
Air pressure Power+ | 1.5 to 3 bar |
Impulses | 200 - 300 impulses / cm2 point |
Frequency | 8Hz to 12Hz |
Applicator | 36mm |
Skin pressure | Light to Moderate |