Police are appealing for information after the incident which took place on the A76 Dumfries to Kilmarnock road, near to the junction with C6N road towards Loch Ettrick at around 2.45pm on Saturday, April 17.
The crash involved a grey Audi A6 and the teenage girl, who was taken by air ambulance to the Queen Elizabeth Children’s Hospital.
Her condition has been described as stable.
The driver and occupants of the Audi were uninjured.
Officers remained on the scene for several hours to for a collision investigation to be carried out and the road reopened around 10pm.
Sergeant Jonathan Edgar of Police Scotland’s Road Policing Unit said: “Our enquires into this crash are continuing and I would ask anyone who saw what happened, and has not yet spoken to officers, to come forwards,
“I would ask motorists using the A76 on Saturday afternoon and who may have been recording via dash-cam devices to check their systems and provide any relevant footage to us as soon as possible.
“I’d like to thank those members of the public who stopped and assisted at the scene, along with our emergency service colleague who attended the incident.”
Anyone with information should contact police on 101 quoting incident number 2221 of 17 April.
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