The hemoglobin A1C (HbA1C) blood test can predict whether partial foot amputation will succeed in diabetics with foot ulcers or whether a below-the-knee amputation will be necessary, according to the findings of a study presented at the American Orthopaedic Foot and Ankle Society's annual meeting (July 29, 2004). Although the finger-stick test diabetics take every day gives a blood-sugar value for that moment, the HbA1C test gives a more long-term assessment of how sugar levels have been controlled over several months. A majority of laboratories consider HbA1C values between 3% and 6% as normal.
In the current study, the researchers compared data from 21 patients with a failed partial foot amputation and 21 similar patients with a successful amputation. Age, sex, smoking, pulse in the foot, and HbA1C were factored into the study. The results showed that an HbA1C value of >10% strongly indicated that a partial foot amputation would fail to heal, compared with values of <7% that usually forecast success. Lead researcher Alastair Younger, MD, stressed, however, that a high HbA1C should not result in an automatic below-the-knee amputation. Instead, surgeons should refer the patient to an endocrinologist or take other steps to improve sugar level prior to surgery.