COMMENT:This type of amputation or "degloving" injury is extremely rare and is usually associated with manual occupations such as in the construction industry and the military (from jumping out of the back of trucks). Common methods to prevent this type of injury are to wear a soft-rubber ring instead of a metal ring, or to remove the ring and wear it somewhere else such as by a thin chain around the neck, or from a string cord with a breakable link (like an O-ring) to reduce the risk of the wearer being garroted should the string necklace get caught on something.
First aid treatment includes wrapping the wound in clean, sterile, moist dressings, applying pressure and elevating the injured hand. Immediate medical assessment is always warranted. If the tissue that was torn off is recoverable then it should be wrapped in a clean, sterile, moist dressing, and chilled (but not frozen or in direct contact with ice). Reattachment, or even partial reattachment, may be possible.
~ Peter Buzzacott, MPH, PhD