Late digital replantation failure: pathophysiology and risk factors

It is generally accepted that replanted digits surviving at least 1 week following surgery rarely succumb to ischemic necrosis. Presented here are 2 patients who experienced late digital replantation failure. The first patient is an 8-year-old boy who had his index finger replanted at the proximal phalangeal level. After 16 days of viability, the replanted digit became swollen and subsequently necrosed. The second patient is a 35-year-old man with a history of smoking and intravenous drug use who underwent replantation of his avulsed thumb at the metacarpophalangeal joint. The replanted thumb was viable at the 2-week follow-up, but began to show ischemic changes at 3 weeks and eventually required revision amputation at the interphalangeal level. Both of these patients demonstrate late digital replantation failure--an unusual and poorly understood phenomenon. A discussion of possible risk factors and potential pathophysiology is presented.