A hip dislocation occurs when the ball-shaped head of the femur is forcibly displaced from its natural socket, the acetabulum, within the pelvis. Because this joint is highly stable, the injury almost always results from significant, high-energy trauma, such as a motor vehicle accident or a fall from a height. The separation of the joint is acutely painful and immediately disabling, preventing the person from bearing weight on the affected leg. A dislocated hip is an orthopedic emergency requiring immediate medical attention to prevent long-term complications. Prompt repositioning is necessary because the longer the femoral head remains out of the socket, the greater the risk of damage to surrounding structures. This injury cannot be managed at home, and any attempt at self-treatment is dangerous.
Recognizing a Hip Dislocation
The signs of a dislocated hip are usually dramatic, often allowing for a diagnosis simply by observing the person’s position. The primary symptom is intense pain in the hip and groin area, coupled with an inability to move the affected leg or bear weight. Muscle spasms around the hip joint are common, further limiting movement.
The abnormal positioning of the limb depends on the direction of the dislocation. The most frequent type, a posterior dislocation, causes the leg to appear shortened, rotated inward, and bent slightly toward the center of the body. Conversely, a less common anterior dislocation may cause the leg to be rotated outward and moved away from the body’s midline. Swelling and visible deformity around the joint confirm the severity of the injury.
Critical Immediate Actions and Risks
The immediate action following a suspected hip dislocation is to call for emergency medical services immediately. Do not attempt to move the injured person, as manipulation risks causing further damage to already compromised structures. The injured leg should be immobilized in the position it was found, and the person should be kept warm until professional help arrives.
Refrain from giving the person any food or drink, as sedation or general anesthesia will be required for the reduction procedure. Trying to “rotate the hip back into place” without professional medical supervision must be strictly avoided due to the extreme danger it poses. The strong muscles and ligaments surrounding the hip are often under extreme tension, and forcing the joint can result in catastrophic complications.
High-Risk Complications
Attempting manipulation without proper imaging and sedation risks severe complications, including injury to neurovascular structures. The sciatic nerve, which runs close to the joint, is particularly vulnerable to crushing or stretching, especially in posterior dislocations. This can potentially lead to permanent weakness or loss of feeling in the lower leg and foot. A primary concern is damaging the blood vessels that supply the femoral head, which can lead to avascular necrosis (osteonecrosis). If the blood supply is cut off, the bone tissue in the femoral head can die, potentially necessitating a hip replacement.
The Professional Reduction Procedure
The procedure to reposition the femoral head back into the acetabulum, known as closed reduction, must be performed in a controlled medical setting. The goal is to return the joint to its proper alignment quickly to reduce the risk of avascular necrosis. The procedure is time-sensitive; reduction within six hours of injury is often cited for better long-term outcomes.
Adequate procedural sedation and muscle relaxation are necessary due to the powerful musculature around the hip. This allows the orthopedic specialist to manipulate the joint without causing further trauma. Techniques such as the Allis or Stimson maneuvers involve applying specific, controlled traction and rotation to guide the femoral head back into the socket. A successful reduction is often accompanied by a palpable or audible “clunk.”
After the reduction, the medical team performs a neurovascular examination. Post-reduction imaging, including X-rays and often a Computed Tomography (CT) scan, confirms correct placement and checks for bone fragments or associated fractures. If closed reduction is unsuccessful or if complex fractures exist, open surgery is required to stabilize the joint.
Rehabilitation and Long-Term Care
Following a successful reduction, recovery focuses on protecting the joint while gradually restoring strength and mobility. The initial phase involves protected weight-bearing, using crutches or a walker to avoid stressing the healing joint. Weight-bearing progression is strictly monitored and guided by the orthopedic specialist based on the injury’s severity.
Physical therapy is a required component of rehabilitation, beginning with gentle exercises to maintain a range of motion. Over several months, the regimen progresses to strengthening surrounding muscles, such as the hip flexors, extensors, and abductors, to restore normal function. Total recovery can take several weeks to many months, depending on the injury’s complexity.
Long-term follow-up is necessary to monitor for potential complications that may arise years after the injury. These include post-traumatic arthritis due to cartilage damage and avascular necrosis. Patients must be regularly assessed for avascular necrosis, which can lead to the collapse of the femoral head, requiring further surgical intervention.