A hip dislocation occurs when the ball shaped head of the femur (thigh bone) moves out of its socket on the pelvis. In most cases, this requires a traumatic force to the thigh bone. It causes severe pain and inability to move the hip joint, so a dislocation is usually fairly obvious. Medical help is needed immediately to put the bone back into place.
Symptoms of a Hip Dislocation
Hip dislocation symptoms are pretty obvious pain at the time of impact or trauma. The patient will be in severe pain, unable to move the joint at all. The leg may appear at an awkward angle often with one leg lying across the other. The greater trochanter of the Femur will be prominent and easily felt.
Causes of hip dislocation
The hip joint consists of the head of the femur (thigh bone) which is ball shaped and the acetabulum of the pelvis - the socket into which the ball fits. The joint is supported by some very strong ligaments. There is also a labrum (ring of cartilage around the acetabulum), which helps to hold the femoral head in the socket. All of these features together make the hip joint a very stable joint. Therefore, a lot of force is required to dislocate it!
Dislocations most often occur from road traffic accidents or falls. Hip dislocations occur more easily in children than in adults. Dislocations are either Anterior, Posterior or Central. 90% of dislocations are posterior. These occur usually from a backward force on a flexed knee, when the hip is also flexed. Dashboard injuries are the predominant cause of this.
Other injuries such as fractures to the Femur or the pelvis are also often associated. There is always some extent of soft tissue damage following a dislocated hip. This may include tears of the labrum or ligaments of the hip joint.
Treatment of a dislocated hip
- Seek medical attention immediately.
- DO NOT attempt to move the leg or hip back into place.
- Once at hospital, X-rays will be taken to rule out fractures, MRI or CT scans may be used if blood vessel, nerve or other soft tissue damage is suspected.
- Provided there are no significant associated injuries then the patient will be given an anesthetic or sedative to allow the doctor to manipulate the bones back into place.
- In some cases the reduction may be performed in surgery under general anesthetic.
- After reduction more X-rays or CT scans will be taken to ensure the bones are in the correct places.
- The leg will be immobilised to allow healing of soft tissues.
- Watch out for neural and vascular symptoms such as numbness, tingling, cold, pale skin and a reduced pulse at the ankle - this could indicate damage to nerves or blood vessels and should be investigated.