What should you do if you accidentally cut off your finger? - Jason Hoellwarth

0:07 After a long day helping patients in the emergency room, Priya is prepping dinner when her knife slips and neatly severs her finger. Fortunately, being an ER doctor, she knows exactly what to do. First, she cleans the wound with a wet paper towel and bandages her finger— careful not to wrap the wound too tightly. To manage the pain. she knows not to take ibuprofen, which would prevent the wound from clotting, and instead opts for acetaminophen. Then she rinses off the severed finger, wraps it in a clean, moist towel, and puts it in a cooler while avoiding direct contact with ice. Finally, she rushes to the hospital,

0:53 where luckily, a skilled hand surgeon is on staff. Thanks to the clean cut and Priya's rapid response, the surgeon can get to work. They set the bones and fix them in place with wires before repairing the tendons, nerves, blood vessels, and finally, the skin. The entire incident is finished in about eight hours, and after a few months of occupational therapy, Priya's hand is back in action. This is the ideal outcome for reattaching a body part. Unfortunately, it’s also incredibly unlikely— and not just because most people aren’t as prepared as Priya. In reality, there are countless complications

1:38 that come up with most accidental amputations. First, there's the accident. Unlike Priya's clean cut, most traumatic amputations occur in car crashes or industrial accidents that cause extensive, uneven tissue damage and dirty the wound in a way that prevents reattachment. Plus, more than half of all limb amputations in the United States are due to disease, and limbs removed for medical reasons obviously aren’t safe to reattach. Then, there’s preserving the limb. When a body part is severed, its blood circulation is cut off, stopping the influx of oxygen and other nutrients.

2:24 Surprisingly, severed tissues can survive for a few hours without these resources. And keeping them cool further slows the rate of tissue death, generally giving surgeons a 6-to-12-hour window for reattachment. But once the tissues die, reconnecting them won’t bring them back to life. This tight timeline is especially challenging for surgeons. Due to the issues we’ve already mentioned, reattachment operations are fairly uncommon. So most hospitals don’t have the tools and expertise required to tackle these time-sensitive procedures. And even if they do, nerve repair is extremely tricky. With perfectly clean cuts,

3:10 surgeons can attempt to stitch nerves back together directly. And when a cut is ragged, they may try to create nerve conduits— tunnels between nerve ends that can allow the nerves to reconnect over time. But neither these, nor any other surgical options, reliably restore movement and sensation. All these obstacles make it highly unlikely that a lost limb can be reattached. However, medical technology has developed another dependable solution for amputation: prosthetics. Today, prostheses come in countless forms to replace numerous body parts. Prosthetic legs are excellent for walking and running.

3:56 Prosthetic arms have historically struggled to replicate our hands’ fine motor movements. However, new myoelectric prostheses can detect electrical activity in nearby muscles and then translate those signals into relatively precise movements. But perhaps the most dramatic development in prosthetic technology is transcutaneous osseointegration. First successfully performed in 1990, this procedure surgically anchors a metal implant into the bone of the remaining limb. The bone then grows into the crevices of the metal, creating a permanent connection. These implants extend through a portal in the skin,

4:42 and can be attached to any prosthesis, which solves a handful of common prosthetic issues. Where traditional prosthetics can be heavy, providing a direct skeletal connection makes their weight feel more natural. Osseointegrated prosthetics are also less likely to irritate the skin where they attach, and they can offer more sensation by transmitting forces like vibration through the implant to the bone. Even with all these new technologies, not everyone wants to replace or reattach a lost limb. After an amputation, some people opt to rely on their remaining limbs, with or without the help of mobility aids and other adaptive equipment.