Lower limb amputation for diabetic foot.

We amputated 35 limbs of 27 patients with diabetic foot from March 1988 to March 1998. The mean age of the patients at the time of operation was 67 years, and the mean follow-up period was 27 months. Thirteen patients died in the period from 1 day to 39 months after the operation. All patients suffering from diabetic foot were referred to our department for surgical procedures after failure of conservative treatment conducted elsewhere. Their feet were classified into grade 2-3 in 18 limbs, grade 4-5 in 11 limbs, and gangrene of the lower leg and entire foot in 2 limbs, as classified by the Wagner system. Two patients had cellulitis of the foot and two other limbs had infectious gonarthritis. All patients had type 2 diabetes with poor blood sugar control, and 90% were treated by insulin. All patients suffered from diabetic neuropathy. Half of the patients were put on hemodialysis because of diabetic nephropathy. More than 60% of the patients suffered from arteriosclerosis obliterans. The amputation level of the limb was determined by skin thermography, but the patient's will was critical. The initial amputation levels were: débridement and synovectomy in 4 limbs, toe and digital ray in 15 limbs, transmetatarsal in 3 limbs, transtibial in 9 limbs, transfemoral amputations in 4 limbs. Upper level reamputation was conducted on 15 limbs. Logistic regression analysis revealed that lower temperature of the amputation site, being female, and being elderly were significant risk factors in reamputation. Skin thermography was one of the effective determinants of amputation level, in order to avoid reamputation.