Coxofemoral Hip Luxation (Hip Dislocation) in Dogs

Overview of Coxofemoral Luxation (Hip Dislocation) in Dogs

Coxofemoral (hip dislocation) luxation is dislocation of the head of the femur, which is the ball of the thigh bone, out of the socket of the pelvis (acetabulum). In dogs, the dislocation is usually the result of trauma and results in a non-weight bearing lameness of the affected limb. Hip dysplasia can also cause coxofemoral luxation and is not covered by this discussion.

Hip dislocation occurs when the round ligament of the femoral head, the structure that normally tethers the femoral head within the acetabulum, completely ruptures or pulls away from its attachment.

There are no breed, age, or sex susceptibilities for this problem.

The potential long-term effects of hip luxation range from none, if the problem is addressed early, to severe arthritis in the joint if there is excessive delay in treatment.

What to Watch For

Signs of hip dislocation in dogs may include:

• Inability to bear full weight on the limb
• Excessive mobility of the limb
• Crackling noise (crepitus) at the joint
• Shortening of the limb

Diagnosis of Coxofemoral Luxation in Dogs

Diagnostic tests that may be required to confirm the diagnosis and determine the presence of concurrent diseases or abnormalities, include:

• A thorough physical examination
• Chest radiographs
• Complete orthopedic examination
• Radiographs of the pelvis
• Laboratory tests are not required to make the diagnosis, but may be indicated depending on your animal’s age and condition.

Treatment of Coxofemoral Luxation in Dogs

Treatment may consist of one or more of the following:

• Emergency care for concurrent problems caused by the trauma.
• Closed reduction. This is the replacement of the head of the femur into the socket without surgery.
• Open reduction. This is the surgical replacement and stabilization of the head of the femur into the socket.

Home Care and Prevention with Coxofemoral Luxation

Take your dog to a veterinarian as soon as possible after any trauma for immediate evaluation.

After closed reduction, the limb will be placed in a sling and your dog’s activity will need to be restricted for several weeks to allow the joint to heal.

If an open reduction technique is used, the leg may be placed in a sling and your dog’s activity restricted. Additionally, the skin incision will be monitored during the healing process.

Radiographs may be repeated in several weeks to make sure the hip is still in the joint.

Many traumatic events are true accidents and thus unavoidable. Walking dogs on a leash and keeping animals confined to a yard will reduce the chances of them being struck by a motor vehicle.

In-Depth Information on Coxofemoral Luxation

Hip dislocations can develop under a number of circumstances. Prominent reasons are trauma and pre-existing hip problems such as hip dysplasia. Take your dog to your veterinarian as soon as possible after any trauma or injury, including those that lead to limping or inability to walk properly.

Early intervention can save your dog from life-threatening injuries and reduce future problems, such as arthritis in cases of orthopedic (bone and joint) trauma.

Traumatic Fractures

When coxofemoral luxations occur due to trauma, the trauma may also cause fractures to occur.

Hip Dysplasia

Hip dysplasia is a developmental abnormality that leads to instability between the head of the femur and the acetabulum. Severely dysplastic hips may be more likely to become dislocated or may be more difficult to keep in the joint after repair.

Veterinary care should include diagnostic tests and subsequent treatment recommendations.

Diagnosis In-depth of Coxofemoral Luxation

• Physical examination. This is important to ensure that your dog is not in shock because of the trauma or associated blood loss. It is also important to make certain that no other injuries are present.
• Chest radiographs. Chest trauma such as pulmonary contusions (bruising) or pneumothorax, which is a collapsed lung, can be identified on chest radiographs. It is particularly important to identify these lesions if your dog is to undergo anesthesia.
• A complete orthopedic examination to look for the cause of the lameness and to determine if other injuries are present. Fractures, especially of the pelvis and femur, are frequently found after a trauma that causes coxofemoral luxations. The examination involves palpation of all of the bones and joints of each leg for signs of pain or abnormal motion within a bone or joint. The neurologic or nerve status of each leg will also be determined. Specific palpation of the hip joint can be highly suggestive of coxofemoral luxation when animals are not excessively painful and there is minimal swelling around the joint. A thorough orthopedic examination is essential to direct appropriate radiographic examination and to allow your veterinarian to discuss the benefits of potential treatments, prognoses, and costs with you.
• Radiographs of the pelvis. Two X-ray views of your dog’s pelvis are used to confirm the diagnosis of hip luxation and will also show pelvic fractures if they are present.
• Laboratory tests. None are required to make the diagnosis, but they may be needed to determine whether concurrent problems exist that might influence anesthesia.

Treatment In-depth of Coxofemoral Luxation

• Emergency care for concurrent problems may be required. Your veterinarian may need to treat your dog for shock by administering intravenous fluids to maintain blood pressure and improving oxygen delivery to the body.
• Wound care may be necessary if lacerations or other wounds are present. These wounds must be cleaned of debris and covered or closed to minimize infections.
• If there are concurrent fractures your veterinarian may wish to stabilize them with splints. Pain medications may be needed to keep your dog comfortable until the fracture can be properly treated.

Closed reduction (non-surgical replacement of joint)

The outcome for this procedure is best when the procedure is performed early after trauma. General anesthesia is needed to replace the femur into the socket.

After the procedure, the limb is placed in a sling to prevent use of the leg and maintain the position of the joint.

Open reduction (surgical replacement of joint)

This technique is used when closed reduction fails, an avulsion fracture is present at the attachment of the round ligament of the femoral head on the femur, or if concurrent orthopedic problems preclude the use of a sling after closed reduction. It too requires general anesthesia.

Open reduction requires that a surgical approach to the hip joint is made to allow direct visualization of the bones and joint capsule. The torn round ligament of the femoral head is removed and the head of the femur is replaced into the acetabulum.

The surgeon may use one of the following methods for maintaining the position and preventing reluxation:

• Joint capsule reconstruction, which is repair of the torn joint capsule
• Prosthetic joint capsule, which is the use of suture material between acetabular rim and femur to prevent the femoral head from moving out of joint
• Toggle pin, which is the placement of a piece of large suture material within the joint to mimic the function of the damaged round ligament
• Greater trochanter translocation, which consists of redirecting the pull of the large hip muscles to force the head of the femur into the acetabulum
• De Vita pin, which is the placement of a metal bar across the rim of the acetabulum to prevent the femoral head from moving out. The pin needs to be removed in several weeks through a small incision behind the animal’s thigh. This technique may also be employed in a “closed” fashion, without the need for an incision.

Home Care of Coxofemoral Luxation in Dogs

After surgery, the limb may be placed in a sling.

After closed reduction you may be required to:

• Restrict activity for several weeks.
• A non-weight bearing sling will be used to prevent your dog from using the limb. Monitor the sling closely so that it does not stretch or move, making it ineffective.
• Administer analgesics for pain or anti-inflammatory medications to keep your dog comfortable.

After open reduction you may be required to:

• Restrict activity for several weeks.
• Monitor the skin incision for excessive swelling or discharge.
• Return for follow-up radiographs in several weeks to make sure the hip is still in the joint.