The project aims to evaluate healing effects of ESWT. If ESWT effectively can improve healing of complicated diabetic foot ulcers, ESWT should be considered for implementation in ulcer treatment clinical guidelines. Better ulcer healing can potentially improve patient's quality of life and decrease the number of diabetic patients who are being amputated (or at least postpone amputations). Later, research may be carried out to refine ulcer ESWT.