Hip fractures are often the result of a fall. Other hip fractures may occur with a high energy injury, such as a motor vehicle accident or contact sports injury. Fractures often cause severe pain, swelling, and inability to bear weight. Dependent on the type of fracture, your surgeon may choose to treat your fracture with a hemiarthroplasty.
Source and for more information: American Academy of Orthopaedic Surgeons (AAOS)