New Method For Restoring Circulation to Amputated Fingers
This report is from microsurgeons from China. They treated 10 patients with finger amputations. After reattaching the fingers, it was clear within a day or two that the replantation the blood that was at the surgical site was pooling, a process called venous congestion. Without proper blood circulation to and from the finger, the reattached (replanted) tissue was dying.

The authors used a newly developed method for restoring blood flow to an amputated finger that has been reattached or replanted. It's called a proximally based cross-finger flap.

In this procedure, the hand surgeon takes the top layer of skin and blood vessels from the finger next to the amputated one (the donor finger) and transfer it to cover the area where the replanted finger is connected back to the affected finger. The donor flap consists of skin, tissue just under the skin, and veins. The tendon is left untouched.

The donor flap is sewn loosely without tension to the replanted finger. The flap of skin is not cut away from the donor finger. Instead, it forms what looks like a bridge between the two fingers. The stripped donor site is covered with a layer of skin called a skin graft. When the replanted finger has a restored supply of blood, the graft can be removed.

This method of proximally based cross-finger flap isn't the only way to handle venous congestion in a newly replanted finger. In mild cases, leeches can actually be applied to the skin. Just as you might imagine, the leeches suck the pooled blood out from under the skin. But leeches aren't enough when there are blood clots forming, skin inflammation with blisters, and/or necrosis (dying tissue).

The authors note that there are other ways to surgically handle this situation. But they suggest this method may work best when there is venous congestion, not enough skin to cover and reconnect the amputated finger, and it's clear that the replantation is in trouble. The cross-finger flap is best applied within 48-hours of the original replant surgery.

Based on this study, it looks like the cross-finger flap is easy to apply (takes less than 90 minutes in the operating room) and quite successful. Microsurgeons performing finger replantations may want to consider this approach if and when venous congestion develops.

Results in this study were very good with return of blood flow, full range-of-motion, and a return to preinjury function. Only one of the 10 patients in this study had a failed surgery and that was because the original injury was a crush injury. One patient did not like how it looked and three people reported ongoing pain when the study ended two years later.
Jianyong Zhao, MD, et al. A Novel Solution for Venous Congestion Following Digital Replantation: A Proximally Based Cross-Finger Flap. In The Journal of Hand Surgery. July 2011. Vol. 36A. No. 7. Pp. 1224-1230.