Is BMX Dangerous?
Let's put the subject of BMX as dangerous into context.
We want to be real here. You might have read, or have been told, BMX is no more dangerous than (insert sport name here). Keep in mind amateur BMX is different than professional BMX. Regardless, BMX has risks and is more dangerous than golf, baseball, or cow-tipping. This isn't competitive crocheting; this isn't BMX racing 1992 Edition.
We'll mention freestyle right quick. BMX freestyle involves performing tricks. Riders can fall, land wrong, slip pedals, and lose their balance among other things. The surfaces used in freestyle are hard and paved. Road rash, bruises, broken bones, getting racked, and concussions can happen. Freestyle is a solo sport, and with practice the art of freestyle can be perfected. The freestyle BMX'ers know they are going to crash at some point. Most freestyle riders are as good at crashing as they are at doing tricks. The freestylers just accept the danger.
BMX racing involves going fast over non-flat tracks with other riders and is the most dangerous cycling sport statistically. In professional BMX racing 8 riders are going 30+ miles per hour and the margin for error is zero. Racers wear helmets and little else. Most protective gear is bulky and a lot is not specifically for BMX racing. Broken bones, concussions, bruises, and spinal/back injuries are real. Being run over is too. Former professional rider Greg Hill has a lot to say about the dangers of modern pro BMX. But pro riding and amateur riding are different worlds. The injury rate in downhill mountain biking is less than 5%; in professional BMX racing it is greater than 25%. These numbers come from UCI and Olympic data. Pro riders are often within 0.100 seconds of each other and all are high performing adult athletes. They race on tracks doing 35mph, and there are no seatbelts. Years of experience are behind them. Pro BMX is dangerous.
Amateur racing is different. BMX racing for amateurs is more on the danger level of high school contact sports. Racing is a contact sport. Bikes and riders collide. Elbows nudge others that are too close. Usually, most kids hit the brakes first though.
Amateur riders are of varying skill and fitness levels. The speeds at your local track aren't 40mph. Most amateurs are children; children are flexible and resilient. They bounce back. The majority of broken bones come from adult racers, almost always the riders' dads. That is why moms go to the races.... to drive the kids home and drop dad off at the ER. If your rider is timid and not comfortable on a bike or racing with others look into league racing at a local track. Leagues help them prepare for active racing. If there is no league in your area go to a track and practice. Most tracks in the U.S. are city owned and open to the public free of charge whenever there is no sanctioned racing taking place.
The more a rider rides the better they get at controlling the bike, learning the obstacles, and developing the determination and mental attitude needed to be a fast and safe rider. BMX is challenging, competitive, and does carry some danger in it. How we survived doing dumb things on BMX bikes in the 80's we'll never know, so it can't be that dangerous.