Chance Bone Fracture Surgery | Treatment | Healing | Symptoms

G.Q. Chance first discovered the Chance fracture in 1948. It is identified as a horizontal fracture along the spine or posterior structures of the spine. Because of the position of the fracture, it is also called the transverse spine fracture. It can cause symptoms of abdominal pain after the person sustains a crash accident or if the person falls from horseback riding. Chance fractures commonly occur today due to lap seat belt use when the driver’s vehicle collides during road accident. The force of the impact will throw the whole weight of the person’s body forward which will bend the body over the seat belt but because the body is suspended, the spine bend and will be twisted forward. The result could be a fractured vertebra from T12 to L4 but the most damaged among all vertebras could be the L2 vertebra.

Chance Fracture Types

Although what is most affected with a chance fracture is the posterior structure of the spine, there can be many types of injury that can be sustained by the patient and these are the following:

• Flexion-compression mechanism. Otherwise known as wedge or compression fracture, the anterior column is wedged or compressed thus varying degrees of compression on the middle and posterior column can happen.
• Axial-compression mechanism. This is what doctors call burst fracture and the bones that are involved here are the anterior and middle columns of the vertebrae which are compressed. This fracture can have 5 subtypes which are:

1. Fracture of both endplates
2. Fracture of the superior endplate
3. Fracture of the inferior endplate
4. Burst lateral flexion
5. Burst rotation fracture

• Flexion-distraction mechanism. Also known as the seatbelt fracture, this involves the injury on the posterior column and ligamentous components of the vertebrae or sometimes both of them.
• Rotational fracture-dislocation mechanism. This is a combination of rotation fracture and lateral flexion fracture.
• Minor fractures. Can include fractures of the transverse processes of the spine, pars interarticularis, and spinous processes. They are usually considered mechanically stable.
• Fractures secondary to osteoporosis. The fractures could involve any of the bones, namely: proximal humerus, proximal femur, distal forearm, and pelvis. These fractures are all secondary to the decrease of bone density and they can get injured easily along with the spine.

Diagnosis

Some forms of chance fractures are sometimes difficult to diagnose so the medical history of the person is needed so that the doctors can rule out if the person really has a fractured spine. There would be the need for a thoraco-lumbar spine X-ray so that it will show if there is a horizontal line fracture along the vertebra. Spinous process can also be recommended by the doctors. If the injury is only a ligamentous injury, the X-ray would not be enough to show the real damage so a CT scan will be used to give more details about the damage. The images produced by the CT scan can be used for the reconstruction surgery but when the spinal cord is already involved, an MRI must be used for diagnosis that is more detailed.

Causes

Some of our doctors assume that chance-type spinal injuries can be the result of hyperflexing the spine around a fulcrum. Moreover, these kinds of injury are often associated with high-speed road traffic accidents wherein the victim is tied up by the lap belt and not the chest seat belt. Which is why when radiographic features is taken from the injury, the images of the fractures of the pedicles are often horizontal, and the fracture line extends transversely along the body of the spine. Another characteristic of a chance fracture is it is distinguished as a burst fracture because most of the injuries have posterior vertebral body that explodes internally.

Chance Fracture Symptoms

People who are suspected of having chance fractures are asked if they are wearing seat belts when the accidents happened. The doctor will also look for symptoms such as:

• Seat belt mark on the body.
• Abdominal pain
• Bleeding in the stomach as will re revealed by CT Scan or MRI
• Ruptured liver, bowel or spleen which will also be revealed by MRI or CT scan

Chance Fracture Treatment

Because chance fractures are fractures of the spine, there can be two kinds of treatment that could be involved. First is the medical therapy wherein the patient can be placed on a Risser table and applied with hyperextension to the thoracolumbar junction plus the use of thoracolumbosacral orthosis or back support so that the spine will have limited motion. The patient must undergo series of test to assess any deformity of the spine. This will be followed by rehabilitation program.

The second option is the surgical therapy. This treatment method will be used if immobilization would be impractical to use or if the patient has suffered multiple trauma in the head or chest. There would be the need to reconstruct the posterior tension band with a hook-pedicle, screw-rod, and rod hook or pedicle screw-construct through surgery. For ligamentous-chance-fracture injury, the same procedure will also be done then followed by stabilization and arthrodesis.

Chance Fracture Healing Time, Recovery Time: It can take more than 8 weeks

Prevention

Since chance fractures are caused usually by lap seat belts or falling from high places or high-impact accidents, it is recommended that all vehicles should have the air bag protection so that the driver is protected during high-speed collision. When playing sports, wearing body padding will definitely protect your spine when you collide with other players or fall to the ground hard.

When to Call A Doctor

Chance fractures are considered serious cases of spine fractures and they sometimes involve internal organs. Therefore, when you think someone has a broken back with or without abdominal pain, call medical help immediately but do not try to move the patient.