Kyphoplasty is a minimally invasive treatment for compression fractures that can occur in the thoracic (the part from which the ribs originate) or lumbar (low back) spine. These fractures usually occur in patients who, for some reason or another, have weak bones. The most common associated condition is osteoporosis, but also other metabolic conditions can lead to bones that can fracture with only subtle trauma.
These compression fractures can be seen best on the side view xray (lateral view) of the spine. The body of the vertebra is usually rectangular in shape. For an analogy, think of a can of soda. The compressed fracture looks like the can is crushed somewhat.
These compression fractures can cause pain not only because having a fracture by itself is painful, but also they can change the balance of the spine.
While a non-fractured spine when viewed from the side has a natural balance where the center of gravity (plumb line) goes through the base of the spine (the sacrum), with a compression fracture and subsequent deformity, the center of gravity moves forward.
The net effect of this change is that
1) the muscles that extend the spine have to work harder to allow the patient to stand up and
2) there is increased risk of having another level fracture since the forces on the other vertebral bodies is increased.
A procedure designed to help correct these issues is called Kyphoplasty.
This procedure involves inserting a needle into the broken bone, through the needle, inserting and inflating a balloon. Bone cement, which is like a doughy glue that hardens in about 15 minutes, is introduced into the fracture space after deflating the balloon. By doing this procedure, several goals are achieved:
–the compression deformity can be corrected, although usually not 100%,
–the fracture is stabilized with significant pain relief.
An example from a patient with a metabolic bone disease is shown below.
This patient is a 28 yr old female with a digestive disorder preventing her from absorbing calcium, fell onto buttocks with compression fracture of L1 seen here on MRI on the left and on regular xray on the right.
Intraoperative fluoroscopic views show the balloons inflated in the bone helping to restore the height of the vertebral body.
The inflation of the balloon also functions to compress some bone around the balloon to prevent the bone cement from being inadvertently injected into the wrong place.
Post operative views are shown here with the bone cement in place. The patient felt better the night of surgery. The view from the front is shown on the left, and the side view is on the right. Note how the neighboring bones don’t look very white, indicating the lack of calcium contributing to the weakness of the bones.
Aside from the risks outlined in the section on this website labelled Risks of Surgery, the main risk with this procedure is that a neighboring or adjacent level will have another fracture. Since this condition usually occurs in patients with weak bones, and since the bone cement is a little harder than normal bone, patients must understand that fracture of the next level is an event that can occur, but hopefully can be avoided.
On the whole, however, Kyphoplasty is generally a procedure with high patient satisfaction. Further information can be obtained at kyphon.com.