Hip fractures involve the proximal portion of the thighbone (femur). Two major types of hip fractures are the femoral neck fracture, when the ball (greater trochanter) is broken away from the femur; and the intertrochanteric fracure, a break just below the femoral neck.

Hip fractures may be the result of high-impact injuries, such as those sustained in an automobile accident. However, bone density loss can contribute to hip fractures after age 65 even in the absence of a traumatic injury; elderly people may experience a hip fracture during minor trauma, such as falling.

Further Reading:

American Academy of Orthopaedic Surgeons: Hip Fractures