Minimally Invasive Kyphoplasty Procedure for an Osteoporotic Vertebral Compression Fracture:
Live Webcast

September 21, 2005: Good Samaritan Hospital, Baltimore, Maryland. Spine surgeons performed a kyphoplasty procedure for osteoporotic and osteolytic vertebral compression fractures during a live surgery webcast. The surgery was performed and moderated by A. Jay Khanna, MD and Mesfin A. Lemma, MD, assistant professors of orthopaedic surgery at Johns Hopkins Orthopaedics at Good Samaritan Hospital. The surgeons also answered emailed questions from the web audience.

Kyphoplasty is a minimally invasive surgical procedure treating osteoporotic and osteolytic fractures where a cement-like material is injected directly into the fractured bone. This stabilizes the fracture and provides immediate pain relief in many cases. Osteoporosis is systemic skeletal disease with loss of bone mass, and microarchitectural deterioration of the bone. Osteolysis is destruction of bone as a result of multiple myeloma or other tumors.

Approximately 55% of all people over 55 have some degree of osteoporosis. 100 million people in the US are at risk for osteoporosis and 8 million women and 2 million men are diagnosed each year. Many of these people will go on to experience fractures. As a result of the fractures many patients show a “humped” back or kyphosis.

From Dr. Lemma: “We should all treat vertebral fractures as a serious and growing problem especially in light of our aging population. It is becoming an epidemic. People don’t realize there are more vertebral fractures occurring than wrist and hip fractures combined. More than 750,000 per year in the US alone. Do the math. That’s one every 24-25 seconds. About a third of those ultimately fail nonsurgical management and become candidates for fracture repair. Keep in mind, if you have one compression fracture the risk for another is increased 5 times. If you have 2 fractures your risk of a third is 12 fold. These vertebral fractures result in disability, immobility, diminished quality of life and compromised lung function if the fractures are in chest region. We need to treat these fractures even more aggressively than we do hips and wrists.”

Dr. Khanna explained the typical treatment plan for a patient with vertebral fracture(s). “We always start with a conservative, non-operative approach. That includes pain control, bracing and bed rest. But, recent studies indicate bracing causes weak muscles and bedrest leads to more bone loss. If the patient’s pain continues then we evaluate surgical repair of the fracture. Before 1997 we had only open spinal repair as a choice. Vertebroplasty and Kyphoplasty techniques were developed in 1998. This was especially helpful since most patients with osteoporosis are older and have lung disease and/or weak bones making them poor risks for open surgery.”

“In a vertebroplasty procedure,” Khanna elaborated, “the interventionalist inserts a small tube into the pedicle of the spine and injects surgical cement. That cement has to be relatively liquid and will follow the path of least resistance. It should stabilize the spine and thus decrease the pain. The pain is relieved but research shows the cement can leak into areas where it is not needed or wanted. In the Kyphoplasty technique we use the same approach but the cement is more controlled.”

Going live to the interventional radiology suite Khanna introduced the patient. “This woman is 68 years old. Her MRI shows the age of the fractures. These appear to be relatively recent. Older fractures may be less amenable to treatment. She’s had 4 years of pain. She’s had CAT scans, MRIs and a bone scan—leading to a diagnosis of multiple lumbar spine fractures. She has failed maximal medical management.”

Pointing at the patient’s X-ray, Khanna noted, “Here you see the vertebral body of the spine is a square. The space in between is the disk space. The magnetic resonance imaging (MRI) shows no fracture at the 3d lumbar level, but she has wedge fractures at lumbar spinal levels 1, 2 and 4. These are active fractures and are quite painful.”

An email from the audience asked: “How long will this procedure take? Lemma answered, “Each level of the procedure takes about 20 minutes to complete.”

Using biplanar fluoroscopy and general anesthesia and with the patient in the prone position, Khanna prepped and draped the patient’s back in the traditional manner. Khanna first approached the L1 level. Using a lateral fluoro view, Khanna first injected local anesthetic. “This will provide pain reduction postoperatively,” he explained. “Now we access the spinal pedicle on the left side first. I’ve made a 4 mm incision on each side, confirming that I’m at the correct level with fluoro.” He then inserted a trocar and cannula into the patient’s back. He advanced the trocar into the vertebral body through the spinal pedicle taking care to avoid the spinal canal.

Khanna then took a biopsy of the disk to confirm the myeloma diagnosis. Next he advanced a drill bit through the cannula into the vertebral body. Manually turning the drill bit produced a channel through which he advanced the kyphoplasty balloon. “This specially designed Kyphoplasty balloon (Kyphon, Sunneyvale, CA) has X-ray opaque markers to track the position of the balloon. We connect the proximal end of the balloon’s filling tube to its filling pump. We can read the amount of fluid and the pressure we are using to measure how much contrast dye we are moving into balloon.”

Another emailed question: “How long does it take after the surgery for the patient to fee pain relief? Lemma answered, “Patients get immediate relief. They go home the same day.”

Khanna then advanced the balloon into vertebral body in the deflated position. Once it was successfully placed on the right side of the spine, he duplicated the process on the left side. “Now we have both balloons in place,” Khanna explained. The balloon were then inflated pushing dye/contrast into the balloon. “We are using the balloon to elevate the endplate—the superior portion of the fracture. We are using a 15 mm balloon to accommodate the fracture pattern and we’re creating a cavity within the pedicle to inject the cement and contain it. Our objective is for height restoration of the vertebra.” The balloon can be sequentially inflated up to 400 psi (pounds per square inch). “We have to balance the pressure of balloon and the force of the bone against it. Here we’re at 200 psi on right side and feeling resistance.” He then passed a hand curette through the cannula and turned it, cutting the disk and loosening up the space in the vertebrae. The balloon was reinserted and inflation continued. Once satisfied with the cavity created, he removed the balloon.

Bone cement (methyl methacrylate) was then mixed. After a few minutes the cement reached the appropriate texture of doughiness (where it doesn’t stick to the surgeon’s glove). Khanna then injected the cement through a tube into the cavity created by the kyphoplasty balloon. “The cement hardens and stabilizes the fracture eliminating the patient’s pain,” Khanna noted. “It is important that we bring up the height of the endplate to reduce potential for other fractures.” Working from both sides, he continued to inject cement until it filled almost the entire vertebral body.

Dr. Lemma then took over and completed identical treatments to the remaining fractures. Once all spaces were completed, the skin was closed traditionally and the wound covered with transparent dressings.

From the audience: “How do your patients react to this procedure? Khanna said, “Their recovery time is very short. Most patients wake up with no pain at all. They go home with no restrictions. Patient satisfaction is extremely high.”

Concluding the presentation and describing the functional outcomes from Kyphoplasty, Lemma explained, “At the Cleveland Clinic, we studied 329 patients with 917 levels. The largest experience we know of. Most of these patients were women. Approximately 25% had multiple myeloma or other malignancies. Their average age was 69 years and some had fractures as old as 5 years. We found their vitality greatly improved and their overall functionality greatly improved. We expect to be able to prove height restoration and we are beginning to consider other cement substances. We are currently managing a randomized controlled study. This technique is very safe and effective.”