Hip dislocations are a relatively uncommon consequence of auto accidents and primarily occur during high-speed collisions. This type of injury usually results from an impact between the accident victim and the dashboard. The dislocation of the hip can be anterior or posterior, depending on the direction of the force, and where along the leg this force is applied. Hip dislocations usually happen together with multiple other injuries including pelvic and long bone fractures, spinal cord injuries, and traumatic brain injury.

If there are no contraindications, the first goal of treatment is reduction, which means putting the hip back into the socket. A dislocated hip that can’t be popped back into the socket (irreducible) is often considered a surgical emergency because there is a high risk of a complication called avascular necrosis.

Avascular Necrosis

Avascular necrosis occurs when the blood supply to the top of the femoral bone is interrupted. Reduction within 6 hours is associated with less than a 5% risk of avascular necrosis, but it goes up to over 50% in patients whose femur remains dislocated for 6 or more hours. Traumatic arthritis can develop from avascular necrosis, and the longer the top of the femur doesn’t have enough blood supply, the more likely it is that traumatic arthritis will develop over time.

Surgery for a Dislocated Hip

Other reasons surgery might be needed include an unstable fracture dislocation of the femur and the acetabulum. The acetabulum is the bowl shaped groove in the pelvis into which the femoral bone fits. Loose pieces of bone and cartilage in the joint need to be surgically removed. Surgery stabilizes the pelvis and bone, and ensures there will be a smooth fit between the femur and the acetabulum.

Rehabilitation for a hip dislocation without associated fractures often includes early weight bearing as pain allows, and gentle range of motion exercises to prevent scar tissue from getting in the way of normal movement. Long-term prognosis mostly depends on whether or not avascular necrosis develops.

Other problems that affect outcomes include sciatic neuropathies, infection, inflammation and arthritis.

Dr. Greg Vigna is a Board Certified Physical Medicine & Rehabilitation physician, motor vehicle injury lawyer and Certified Life Care Planner. He understands how long term disabilities complicate recovery and have a direct impact on quality of life and one’s ability to work. Secondary injuries and long term complications should always be considered when there is a serious, high speed accident.