A hip dislocation occurs when the head of the femur is forcibly separated from the acetabulum, the socket in the pelvis. This displacement of the ball-and-socket joint is a serious medical emergency requiring immediate attention. Attempting to bear weight on a dislocated hip is generally impossible and extremely dangerous. The immense force required to disrupt this highly stable joint suggests the presence of severe associated injuries.
Understanding the Immediate Physical Impact
The dislocated hip joint immediately presents with severe, acute pain that makes any movement excruciating. This overwhelming pain is accompanied by a complete inability to bear any weight on the affected leg, meaning standing or walking is functionally impossible. The powerful muscles surrounding the hip joint often go into spasm, further locking the limb into an abnormal, fixed position.
In the vast majority of cases (about 90%), the femoral head is pushed backward in a posterior dislocation. This displacement causes the lower leg to appear shorter than the uninjured side, with the knee and foot rotating inward.
Less frequently, the femoral head is forced forward in an anterior dislocation, causing the leg to rotate outward. The extreme force carries a high risk of damaging surrounding soft tissues. The sciatic nerve is particularly vulnerable to stretching or compression, with injury occurring in up to 10% of cases.
Damage to the blood supply is a concern because vessels feeding the femoral head can be torn during separation. This disruption leads to avascular necrosis, where bone tissue dies from lack of blood flow. Structural instability, intense pain, and nerve damage make the injured limb completely non-functional.
Essential Steps for Emergency Care
A hip dislocation is an emergency, and the immediate response is crucial for minimizing complications. The first step is to call for emergency medical services, as professionals are required for safe transport and treatment. Do not attempt to move the injured person unless necessary, as manipulation risks causing further damage to nerves or blood vessels.
The priority until medical help arrives is to keep the person still and calm, ensuring the injured hip remains in its fixed, abnormal position. If possible, the limb should be immobilized using makeshift splints or supports to prevent inadvertent movement during the wait. It is important to avoid giving the person anything to eat or drink, since they will likely require sedation or anesthesia soon after arriving at the hospital.
Checking for circulation and sensation below the injury involves looking for signs like paleness, coolness, or numbness in the foot and toes. Paramedics will secure the patient and the injured limb onto a gurney, avoiding attempts to “pop” the hip back into place at the scene. The goal is rapid, safe transport to a trauma center where diagnosis and imaging for associated fractures can be performed before any reduction is attempted.
Clinical Reduction Procedures
Upon arrival, the primary goal is to reduce the hip, repositioning the femoral head back into the acetabulum. This must be performed urgently, ideally within six hours, to significantly reduce the risk of avascular necrosis. Because the muscles are powerful and the procedure is extremely painful, reduction is performed under procedural sedation or general anesthesia to relax the surrounding tissues.
The most common intervention is a closed reduction, a non-surgical procedure where the physician guides the joint back into position. For posterior dislocations, this involves applying longitudinal traction to the thigh while performing rotation movements. Successful closed reduction is confirmed immediately with imaging to ensure the joint is properly seated and to check for bone fragments dislodged during the trauma.
If the closed reduction fails after a few attempts, or if imaging reveals associated fractures of the femoral head or acetabulum, an open reduction is required. This procedure involves surgery to directly visualize the joint and remove any bone fragments or soft tissue that are blocking the socket, which would prevent a successful closed reduction. Open reduction is also necessary when the joint remains unstable after a closed reduction, or if there is significant associated neurovascular damage that requires surgical repair.
The Recovery and Rehabilitation Process
Once the hip is reduced and stabilized, recovery and rehabilitation begins, often lasting several months. The initial phase requires restricted weight bearing, often for six to twelve weeks, to allow the joint capsule and surrounding soft tissues to heal. The exact timeline for full weight bearing depends heavily on the severity of the initial injury and whether any fractures were present.
Physical therapy (PT) plays a primary role in recovery, beginning with gentle exercises focused on regaining hip stability and range of motion. The rehabilitation program strengthens the muscles around the hip and pelvis to protect the joint and prevent re-dislocation. Patients must adhere to specific precautions, such as avoiding excessive hip flexion or certain rotational movements, for a period of weeks to months.
Monitoring for long-term complications remains a concern throughout recovery. Post-traumatic arthritis, which develops years after the injury due to joint cartilage damage, is an issue. Patients are also monitored for signs of avascular necrosis, which may not become apparent until months after the initial event. Most individuals can expect a return to normal function within two to three months, provided they follow the structured rehabilitation protocol.