The CV joint, also known as a constant velocity joint, is integral to the proper motion of the wheels on a vehicle. Properly kept up, a CV joint can last upward of 100,000 miles; however problems have been known to occur at much lower mileages where care is not as thorough.
Cause of Joint Failure
When the boot protecting the CV joint is torn, the lubricant which protects the joint and keeps it operating smoothly leaks out. When the lubricant has fully run out, the friction produced by the metal-on-metal motion of the joint can cause difficulty in steering, wobbling in the wheel(s), or even prevent any further motion at all.
Any of the above problems, particularly if the wheel was to stop moving altogether, can cause an accident. On a road that is not crowded or prone to much traffic, this could simply cause a breakdown, and not necessarily an accident.. On a busy road, however, such an issue occurring could certainly cause an accident involving another vehicle.
At routine inspections, make sure the mechanic checks the CV joint boot for any tears. If there is already a problem, bring the vehicle to a mechanic as soon as possible to repair the damage and avoid an accident.