In a multicenter randomized clinical trial , including 30 hospitals and all 10 HBOT centers in the Netherlands , we plan to enroll 275 patients with Types 1 or 2 diabetes , a Wagner 2 , 3 or 4 ulcer of the leg present for at least 4 weeks , and concomitant leg ischemia , defined as an ankle systolic blood pressure of < 70mmHg , a toe systolic blood pressure of < 50mmHg or a forefoot transcutaneous oxygen tension ( TcpO2 ) of < 40mmHg .