MSK imaging, intervention head for explosive growth

Several groundbreaking trends in the subspecialty fields of musculoskeletal imaging and intervention surfaced at the 2006 RSNA meeting. Research presented suggests that conditions traditionally managed by surgeons are increasingly coming under radiologist control. Interventions intended to palliate or cure MSK disease are also being used to prevent it.

Dr. Nicolas Amoretti, an interventional radiologist at the Centre Hospitalier Universitaire in Nice, and colleagues prospectively reviewed data from 86 patients who underwent percutaneous CT-guided repair of post-traumatic sacroiliac disruption. Researchers found the procedure to be a safe and viable alternative to open surgery. The procedure lasts two hours, and most patients can stand in two days. Fewer than 20% of patients experienced residual pain.

In a second study, Amoretti and colleagues reviewed preliminary results from the first 30 patients undergoing CT-guided percutaneous spinal arthrodesis (transfacetar screw placement) using a posterior approach. A radiological-surgical team performed the procedure at the CT table and under fluoroscopic control. Twenty-seven patients have shown clinical improvement, no lumbar pain, and stabilization of the immobilized lumbar segment three months after intervention. They had one major complication. The procedure takes two hours to perform and requires a two-day hospital stay and periodic follow-up, and the patient must wear a corset for two months.

A paper by Dr. Nobuo Kobayashi, a radiologist at St. Luke's International Hospital of Tokyo, reported on prophylactic vertebroplasty-cement injection adjacent to fractured vertebrae to prevent new compression fractures. A previous study by his group had identified a high number of new fractures predominantly in superior vertebrae adjacent to previously treated ones. After performing prophylactic vertebroplasty in 80 consecutive patients, the researchers found the number of new fractures dropped by nearly two-thirds after three months and by half after a year.

In another study, Dr. Amy B. Kirby, a radiology fellow at the University of Oklahoma, and colleagues successfully treated 11 patients with osteoporotic fractures using allograft bone. Insertion of a mesh inside fractured vertebral bodies is combined with injection of a bone graft compound under general or partial anesthesia.

The procedure, dubbed Spineoplasty, costs an estimated $4100, expensive compared with vertebroplasty or kyphoplasty. It could represent significant savings, however, if proven effective in the long term. It also could avoid complications derived from the use of cement since it's based on a bone graft, said coauthor Dr. Douglas P. Beall.

In a final wrap-up, Dr. David C. Levin, a professor of radiology at Thomas Jefferson University in Philadelphia, and colleagues found that radiologists perform most diagnostic and minimally invasive interventional musculoskeletal studies in the U.S. Data also showed that the volume of MR studies allocated to orthopedic surgeons was currently only 5% of the radiologists' share but rising rapidly.

"The trend in MSK MR use by orthopedic surgeons may bear further watching," Levin said.

Another study by Jefferson researchers found that, with the exception of marrow aspiration, radiologists perform most percutaneous bone biopsies. But the investigators also found that the rate of bone biopsies performed by surgeons, particularly orthopedic and neurosurgeons, is rapidly increasing.