Charlotte Allerton, of Hartshead, West Yorkshire, was rushed to a Leeds hospital but surgeons could not sew her finger back on.
The injury happened when the string of the yo-yo became trapped as she was playing on her slide and wrenched off part of the index finger on her right hand.
The girl's mother Mavis said: "I heard her scream and ran outside to see Charlotte coming towards me crying. Part of her finger was missing - I could not believe it."
Missing finger
After grabbing a bag of frozen peas to stem the flow of blood, Mavis called for her other two daughters, Ruth and Jodie, to help.
"I asked one to ring 999 and the other to go and rescue the missing bit of the finger. She returned with it a few minutes later," said Mavis.
"The ambulance only took 14 minutes to arrive but it seemed like an age."
Despite rushing Charlotte into surgery, doctors said they were unable to attach the finger back on.
"We said goodbye to the little bit of finger. She has asked me a lot of questions and has accepted that she won't have a nail again on that finger."
Charlotte will have to return to hospital for another operation on her finger.
Mavis is now warning other parents of the dangers of yo-yos if they are not used properly.
"It could have been Charlotte's neck, not her finger, that got caught up in the string," she said.
Sales booming
David Lodge, a principal officer with West Yorkshire Trading Standards, said banning yo-yos would be "unrealistic".
"Like any product entering the shops they have to pass tests. I suppose the potential for injuries could be there if used improperly, but that is the same with a lot of things.
"Parents have got to give regard to the age of children using the yo-yos and decide if they are old enough to safely use them."
In recent months a yo-yo craze has swept across the country. Companies have reported a huge increase in sales - driven by new hi-tech yo-yos.
John Howard, of PMS International, said that last year the company sold only a few hundred of the toys - but he expected that by the end of next month sales so far this year would top 500,000.
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Ups and downs of yo-yos
(28 Sep 98 | UK)
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