Take 2 cyclists, one a wannabe.
Add 1 cyclocross bike with knobbly tires. Liberally apply competent biker to the ‘cross bike and make the somewhat incapable newb ride his normal road bike with slick tires.
Stir in some sand and gravel. Apply a dollop of dirt.
Garnish with a wooden 5′ 4×4 lollipop.
Bake at 15mph for approximately 0.1 seconds; ensure that you use your finger against said lollipop column to cause a 200g deceleration.
Hey presto, you’re now the proud owner of a splint courtesy of a dislocated proximal inter-phalangeal joint on your index finger:
How not to wrap a splint
October 19th, 2008 | 
Leave that riding in the dirt to the horses. They never fall. Of course, you could get a motocross motorcycle and some gear and be much safer….
Sorry to see your hand wadded up.
Crap! That totally blows!