"riding accident" is a correct and usable phrase in written English.
For example, "The young girl was injured in a riding accident last week."
A riding accident demanded immediate amputation.
I started outdoor swimming after a horse riding accident.
During a business trip to Frankfurt, George is killed in a horseback riding accident.
Mrs. Guest began her writing career while recovering from a horseback riding accident in 1976.
Since his riding accident, he had fathered another five daughters, but only one survived into adulthood.
A riding accident in 1995 had left the actor paralyzed from the neck down.
The thought of riding accident-prone buses on the back-breaking, 350km-long journey to Katine seemed prohibitively punishing.
Soon after his horse-riding accident, Christopher Reeve contemplated suicide.
Christopher, who was paralysed in a horse-riding accident, predeceased him in 2005.
Her mother, who was left permanently brain-damaged by a horse-riding accident in 1991, has been her biggest inspiration.
Christopher Reeve died at 52 in 2004 after a horse-riding accident in 1995 had left him a quadriplegic.
