[Open or closed minor amputation for diabetic gangrene?].

BACKGROUND

Amputation below the ankle at the diabetic foot is rarely successful, if carried out as closed amputation (with primary wound closure).

AIM OF THE STUDY

To assess the outcome of open and closed (minor) amputations in diabetic patients from three hospitals. Patient charts including pathohistology reports were evaluated.

PATIENTS

A total of 80 diabetic patients were considered, of whom 47 had critical foot ischaemia (CFI) Fontaine stage IV, 5 had endstage renal failure with haemodialysis treatment, and 72 had polyneuropathy.

RESULTS

During 96 procedures, 60 toes and 48 metatarsal bones were amputated. A closed amputation (CA, n=54), or an open amputation (OA, n=42) had been performed, at the discretion of the surgeons. Toes rather than metatarsal bones were amputated more often with CA than with OA (p=0.0018). Following CA, 14 wounds (26%) healed by primary intention, whereas 40 wound did not; in 15 cases (28%), reamputations were required. Following OA, 26 wounds (62%) healed by secondary intention, and 14 cases (33%) required reamputation. Histopathology revealed osteomyelitis at the osteotomy site in 34 cases (64%) of CA, versus 31 cases (78%) of OA. Following CA, 77% of 9 cases without CFI, and with healthy bone at the osteotomy site healed by primary intention, versus 4% of 25 cases with CFI and osteomyelitis at the osteotomy site (p<0.0001).

CONCLUSION

Closed amputation was successful only in absence of CFI and of osteomyelitis at the osteotomy site. The extension of osteomyelitis was grossly underestimated. Preoperative MR imaging (rather than X-ray) to diagnose osteomyelitis could improve the outcome of a closed minor amputation, and justify its preferred application at the diabetic foot.