VERTEBROPLASTY AND KYPHOPLASTY

Up to 250,000 fractures of the bones of the spine—vertebra—occur each year in the US. Most of these are compression fractures in which a vertebra collapses due to osteoporosis. Most fractures occur in normal activities or minor incidents such as a misstep or minor fall.  The vertebra break if they are too weak to withstand the forces exerted on them. About half of vertebral fractures occur without symptoms of pain—they are silent. Others can be excruciating, but the majority of these heal spontaneously on their own in about six weeks with excellent result. Moreover, fracture induced pain should begin to improve significantly within two weeks. In the healing period, standard therapy includes pain medication, including narcotics, progressive activity in rehabilitation, and a brace as needed. Once healed, the risk of renewed fracture is high and patients must follow a medical regimen to aggressively treat underlying osteoporosis.

For the relatively few fractures due to osteoporosis which do not heal, or those fractures resulting from uncontrolled cancerous tumors or benign blood vessel abnormalities within the vertebra , vertebroplasty or kyphoplasty may be used.

Vertebroplasty relieves certain bone pain by the injection of bone cement, in liquefied form, usually into the vertebra, although some cases of hip fractures due to cancer have been treated successfully with vertebroplasty.  (The cement is a paste when injected under pressure but hardens quickly once inside the bone into a hard cement within 10 minutes. The procedure is performed in a radiological facility under intravenous anesthesia.)  I learned this technique in France in the 1990’s and, to my knowledge, was the first American to use it in the US on a patient suffering from cervical cancer which had invaded the lower spine and sacrum. Despite radiation therapy and chemotherapy, her tumors had grown. Her pain was poorly controlled with intravenous narcotics. She knew she was dying but enjoyed watching films at home. Sitting was impossible for her due to pain—limiting her ability to enjoy her films. I decided to treat five different areas affected by her cancer in the same procedure. Within 20 minutes of awakening from her anesthesia, she was able to sit without pain and was able to enjoy her films for the remainder of her life, living much happier than she may have done otherwise. She watched Gone With The Wind as soon as she went home—off intravenous narcotics—within two days of the procedure.

Kyphoplasty is similar to vertebroplasty except that it not only strengthens an injected vertebra, but was designed with the goal of correcting spinal deformity—kyphosis or an exaggerated bent over posture– due to the fractured bone. Vertebra may fracture like a cupcake being partially squashed or, alternatively as a wedge, with the front of the vertebra  towards the inside of the body of a lesser height than the back of the vertebra. In order to correct the anatomy of the deformed, compressed, fractured vertebra, an expanded balloon catheter is used to create a cavity in the bone, after which the balloon is deflated and withdrawn, and the cavity filled with cement under low pressure. The cement hardens in place and maintains the integrity of the vertebra and the spine. It is performed under intravenous anesthesia in a radiological suite or an operating room.

I believe in using vertebroplasty and kyphoplasty in the right patient and in the right situation. In appropriately selected patients they may be 90% successful in treating pain. Unfortunately they are often used excessively in the US.  For a host of reasons—including my strict requirements for patient selection– I perform few of these procedures today. All too often I am referred an osteoporotic patient whose pain emanates from stenosis in the lower spine but for whom I am asked to treat a fractured vertebra in the upper lumbar spine—one that is not even a new fracture.  Fractures older than 6-8 weeks should not be treated by vertebroplasty or kyphoplasty unless they re-fracture—they are healed by then. MRI s can be useful in judging the time a vertebra has been fractured and whether or not an old fractured vertebra re-fractures.

Kyphoplasty is not only ineffective in correcting forward bending spinal deformity, or kyphosis, but actually may result in further kyphotic fracture of the injected bone, worsening the situation. It may be used in correcting a “cupcake” collapse in the right situation.

Moreover, vertebroplasty and kyphoplasty are not without risk—one of which is increasing the risk of osteoporotic fractures of vertebra next to an injected one, by twofold. I have used vertebroplasty mostly in cancer patients in the past. Patients with cracks in the back of the vertebral body, as seen on CT scan, cannot be treated with vertebroplasty and kyphoplasty, as the cement injected into the body may leak through the cracks into the spinal canal, compressing nerves or the spinal cord, raising the likelihood of urgent or emergent surgical decompression. The patients undergoing these procedures are often elderly and osteoporotic; in a higher risk group for serious operative and post operative complications. Osteoporosis is better prevented today than 15 years ago. More attention is made to preventing fractures than before by giving drugs which increase bone density early on in conditions leading to osteoporosis. Similarly, cancer treatment and pain management are better as well. There is still a role for vertebroplasty, and its newer cousin kyphoplasty, but these techniques are still overused in my opinion.