Intermediate-term outcome of primary digit amputations in patients with diabetes mellitus who have forefoot sepsis requiring hospitalization and presumed adequate circulatory status

Purpose: The intermediate success and outcome of primary forefoot amputatio ns in patients with diabetes mellitus who have sepsis limited to the forefo ot and presumed adequate forefoot perfusion, as determined by means of noni nvasive methods, was studied. Methods: Cases of a university hospital-based practice from January 1984 to April 1998 were retrospectively reviewed. Patients included had diabetes m ellitus with forefoot sepsis requiring immediate hospitalization for digit amputations who had adequate arterial circulation for healing based on noni nvasive and clinical assessment: palpable pedal pulses (29%), "compressible " ankle pressure of 70 mm Hg or higher (48%), pulsatile metatarsal waveform s (67%), and/or toe pressure higher than 55 mm Hg (36%). All patients under went a primary single- or multiple-digit amputation (through the interphala ngeal joint, metatarsal head, or metatarsal shaft). Additional forefoot pro cedures (debridement, digit amputation) were performed during, the follow-u p period as needed for persistent or recurrent infection. The main outcome variables were recurrent or persistent foot infection (defined as requiring rehospitalization for antibiotics, wound care, and/or reoperation), the nu mber of repeat operations and hospitalizations for salvage of limbs with re current or persistent infections, and time to complete forefoot healing or foot amputation. Results: Ninety-two patients who had diabetes mellitus with 97 forefoot inf ections comprised the study group. Ninety-seven primary digit amputations ( 34 through interphalangeal joints, 28 through metatarsal heads, 35 through metatarsal shafts) were performed. The median length of hospital stay was 1 0 days. There were no operative deaths. The mean follow-up period was 21 mo nths (range, 3 days to 105 months). The primary amputation healed (without persistent infection) in only 38 limbs (39%), at a mean time of 13 +/- 10 w eeks. Twenty-three limbs (24%) had not healed the primary amputation with o ut evidence of persistent infection at last follow-up (mean, 12 weeks). Inf ection persisted in 35 limbs (36%), and infection recurred in 15 of 38 (40% ) healed limbs. An average of 1.0 reoperations (range, 0 to 3) and 1.6 reho spitalizations (range, 1 to 4) were involved in salvage attempts in these r ecurrent/persistent infections. Five persistent and five recurrent infectio ns ultimately healed (mean, 53 weeks). Complete healing was achieved in onl y 33 of 97 limbs (34%). Twenty-two foot amputations (20 transtibial, two Sy me's) were performed (mean, 49 +/- 74 weeks; 20 for persistent infection). Eighteen persistent recurrent infections remained unhealed at the last foll ow-up examination (mean, 105 weeks). Conclusion: Patients with diabetes mellitus who have sepsis limited to the forefoot requiring acute hospitalization and undergoing primary digit amput ations have a high incidence of intermediate-term, persistent, and recurren t infection, lending to a modest rate of limb loss, despite having apparent ly salvageable lesions and noninvasive evidence of presumed adequate forefo ot perfusion.