Mr. Zink was the coolest teacher in my middle school. Everyone liked him: nerd, jock, cheerleader alike. He taught science, and if you were lucky you got him two years in a row. In those few minutes after the lesson finished, but before the bell rang, he would tell us the grossest stories that he knew.
I still remember them. The one about the kid playing basketball with his class ring on, who left his ring and its attached finger on the rim after a dunk, connected by all the tendons from his finger to his shoulder. (Can that really happen?)
She had avulsed the skin off her ring finger of her right (dominant) hand whilst attempting to jump over a spiked fence, catching her ring on the spike.
The physics/mechanics of the injury is explained well here.
The first 1998 study conducted under Dr. David M. Kupfer, Department of Plastic and Orthopaedic Surgery, University of San Diego in California, involved dropping a 30-pound weight attached to a ring bearing finger hanging from a hook, from a 9-inch height.Results showed that in more than 90% of cases, the injuries caused by rings and wedding bands are Class II (29%) and Class IV (61%). On the tested sample (41 fingers), Class I injuries (10%) occurred at less than 80 N and the first ring avulsions at 111 N. Maximum finger resistance is 346 N with average resistance at 154 N. Film records also show that the skin is the finger’s strongest part. Once the skin tears, the remaining finger degloves or quickly avulses. Accordingly, although thin and narrow or tight rings are less resistant to traction and cause the skin to shear under traction, they are more dangerous than wide, thick rings.
Classification of Injury (Urbaniak)
- Circulation adequate.
- Standard bone and soft tissue treatment is sufficient.
- Circulation inadequate.
- Vessel repair preserves viability permitting immediate or delayed repair of other tissues
- Complete degloving or completed amputation.
- Judgement is essential because, although a complete amputation can be revascularised and viability restored, the potential for function is limited.
- In degloving injuries, the potential for useful function exists, but revascularisation is not easy or may not be possible.
These injuries are best avoided.