Each year, hip fracture, an injury that can impair independence and quality of life, occurs in about 280,000 Americans and 36,000 Canadians. The annual healthcare costs associated with this injury are expected to soon reach $9.8 billion in the United States and $650 million in Canada. It is important to have in place optimal practice guidelines for the surgical handling of this injury. One type of hip fracture, called a femoral neck fracture, is often treated with a surgical procedure called internal fixation. When performing internal fixation, most orthopaedic surgeons favor using multiple small diameter screws over using a single large diameter screw with a sliding plate. However, use of the sliding hip screw might in fact result in fewer complications after surgery and reduce the need for a second surgery, called a revision surgery. This study will compare the two different surgical procedures to determine which one results in better outcomes after surgery.

One type of hip fracture, called a femoral neck fracture, involves a break in the narrow part of the femur bone where the head of the femur is joined to the main shaft. The break can be either undisplaced, which involves very little separation at the fracture site, or displaced, in which there is substantial separation. Surgeons agree that the best surgical procedure for an undisplaced fracture is internal fixation, in which a mechanical implant reconnects the two separated segments of bone. For displaced fractures, surgeons usually choose between internal fixation and a hip joint replacement.

There is more than one way to perform internal fixation. The majority of orthopaedic surgeons currently favor the use of multiple small diameter cancellous screws. However, an alternative method that uses a single large diameter screw attached to a sideplate, called a sliding hip screw, has been gaining popularity and might reduce post-surgical complications and the need for revision surgery. Which surgical method is best for the patient is unknown. This study will compare the use of multiple small diameter cancellous screws versus a single sliding hip screw on rates of revision surgery 2 years after patients sustain femoral neck fractures and undergo internal fixation. The study will also compare the impact of the two different surgical procedures on the overall health, function, and quality of life of patients. Results from this study may impact current orthopaedic practice.

Participation in this study will last 2 years. Before surgery, participants will complete a baseline assessment that will include x-rays, a medical history review, and a physical examination. Participants will then be randomly assigned to undergo one of two types of internal fixation surgeries for repairing their hip fractures. In one group of participants, surgeons will use at least two small cancellous threaded screws that have a diameter of at least 6.5 mm. In the other group of participants, surgeons will use a single large diameter screw that is partially threaded. This screw, called a sliding hip screw, will be affixed to the femur bone with a sideplate, and there will be no other fixations. All surgeons, who will need to meet certain criteria to partake in the study, will follow the manufacturers' technique guidelines for using either type of screw. Specific aspects of both the pre-operative and post-operative care, such as the use of antibiotics and calcium supplementation, will be standardized for all participants.

Follow-up assessments will be completed either by phone or in-person at the hospital or clinic. They will occur 1, 2, and 10 weeks after surgery and 6, 9, 12, 18, and 24 months after surgery. All assessments will include questionnaires and interviews on health status, hip function, pain, and revision surgery. Some of the in-person assessments will also include x-rays.

Inclusion Criteria:

• Fracture of femoral neck
• Operative treatment within 4 days for displaced fractures
• Operative treatment within 7 days for nondisplaced fractures
• Ambulatory before the injury
• Low energy trauma, such as falls from a sitting or standing position
• No other major trauma

Exclusion Criteria:

• Unsuited for both surgical treatments
• Associated major injuries of the lower extremities
• Retained hardware around the hip
• Infection around the hip
• Bone metabolic disorder (except for osteoporosis)
• Moderate or severe cognitive impairment
• Parkinson's disease or dementia
• Unable to complete the 2-year follow-up