Because of the promising association between ESWT and tissue healing, the favorable risk / benefit profile of the devices approved for treatment of soft tissue indications, and the European clinical experience with ESWT for wound healing, it is hypothesized that extracorporeal shock wave treatment (ESWT) could be beneficial in treating diabetic foot ulcers. Therefore, this IDE describes a clinical study designed to determine the safety and effectiveness of the DermaGold® ESW System when used to induce healing of chronic plantar foot ulcers in patients with diabetic foot ulcers.