A young girl was thrown from her pony into a ditch after trailbike riders hared past her.
Isobel Childs, 10, suffered a fractured foot and has been left temporarily in a wheelchair following the incident which took place on private land in Lowick, near Thrapston.
Now her mum Sarah has appealed for byway signs to be reinstated and for the trailbikers to stop riding in the area.
Sarah said: “She was on her pony in Woodford Lane along the byway, which is closed to traffic.
“There was one lad coming down on a bike and a dog walker in front of us signalled him to slow down.
“Then we heard others, and the horse just got spooked.
“Isobel ended up in the ditch and the pony cantered off.
“They aren’t allowed to go down there, it’s private land belonging to the Drayton estate but there are often lots of them down there.”
Isobel was treated for a fractured foot and a damaged shoulder and is in a wheelchair because she cannot use crutches.
Sarah is now appealing for the county council to reinstate signs to make it clearer that trailbikes are not allowed down the track.
She said: “The byway sign at the bottom of the road has fallen off and there needs to be notices up to make it clear.
“There are a lot of children riding ponies in Lowick and I just don’t want this to happen to anyone else.
“I hope Isobel isn’t put of riding by this.”
A Northamptonshire Police spokesman said anyone with concerns about trailbikes riding illegally should call them on 111.