Traumatic injuries can be intentional (assaults, gunshot wounds, stab wounds) or unintentional (falls, motor vehicle crashes [MVCs]). Multiple traumas that result from an MVC often involve several systems of the body and musculoskeletal injury. Falls and MVCs account for a high percentage of the fractures seen today. Children at play take falls as a matter of course and only occasionally suffer fractures. Their most common fractures are of the clavicle. Adults who fall more often fracture a hip or wrist. Osteoporosis increases the likelihood of fractures from a fall; it even sometimes causes a fracture from a slight shift in the body's position, which then results in a fall, rather than the reverse.