Current and Prospective Management of Vertebral Compression Fractures and Osseous Spinal Metastases
Meeting Highlight from NASS 2014
During the "Compression Fracture: Bone Augmentation and Management" symposium at NASS 2014, Sean Tutton, MD, FSIR presented Devices with Unique, Applicable, Anatomic and Pathologic Applications. Dr. Tutton is Professor and Director of Vascular Interventional Radiology at the Medical College of Wisconsin in Milwaukee.
Tailored Approach to Treatment
Understanding that not all patients or vertebral compression fractures (VCF) are the same has led physicians to tailor their treatment approaches. Consider the different types of fractures; pathologic versus traumatic, osteoporotic versus cancer-related, kyphotic deformity, and lumbar fractures. Is the fracture stable or unstable? Is the pain from the fracture or the cancer itself? Is the tumor lytic, mixed, or blastic? Is it a burst or complex fracture? “So to think of all these fractures and these people, and that one device or one procedure could treat them all doesn’t make any sense,” stated Dr. Tutton.
Fracture Treatments Have Evolved
The treatment of spinal fracture has evolved, including:
- Cements and needles
- Vertebroplasty kits
- Balloons and balloon kyphoplasty
- Curved needles in vertebroplasty
- Implant-based technologies
PMMA has some undesirable effects; it is not bioactive; it is a stiff material, and there is concern for adjacent level fractures. It was hoped balloon kyphoplasty would restore vertebral height and offer kyphotic angle correction, “but the papers have not definitely showed that it’s a durable correction, and there have been subsequent and adjacent fractures that have plagued our patients,” Dr. Tutton stated.
Several VCF treatments are currently only available in Europe, such as stentoplasty with Synthes Vertebral Body Stenting-System (Synthes GmbH, Oberdorf, Switzerland), SpineJack® (Vexim, Balma, France), and OsseoFix® (Alphatec Spine, Inc., Carlsbad, CA), Dr. Tutton commented:
- “Synthes’ VBS stent [is] a balloon angioplasty to inflate the stent and then subsequent injection of cement.”
- “Vexim’s SpineJack® is delivered to elevate the endplates and then [is] followed by an injection of cement, and clearly some nice results that have been published in a small series in some comparative trials in Europe.”
- “Alphatec’s OsseoFix [is] a very similar molly bolt construction, should have very good support of the endplates allowing cement installation and interdigitation.”
First FDA-approved PEEK Implant
The Kiva® VCF Treatment System (Benvenue Medical, Inc., Santa Clara, CA) is the first PEEK implant to be FDA-approved in the United States (US). Kiva is an unipedicular, PEEK-OPTIMA® implant, solution for vertebral augmentation and a departure from balloon kyphoplasty making it the first new approach to the treatment of vertebral compression fractures in over a decade.
The KAST trial (Kiva System as a Vertebral Augmentation Treatment) was a prospective randomized trial, with 21 sites in the United States, Europe and Canada. Three-hundred (300) patients were enrolled over the course of 18 months with one-year follow-up. Based on the KAST trial and the strength of the data, it was FDA approved in January 2014. Furthermore, Kiva has been studied extensively in Europe as well. More than 500 patients were enrolled in three comparative or prospective randomized trials; 1,000 implants in the United States. The results of these studies will be published soon.
Spinal Metastases and Primary Tumors
“Moving on to spinal metastases and primary tumors, the vast majority of these are [treated] for palliation and stabilization. Radiation therapy through the Cochrane analysis, and a number of other analyses have been shown not to be durable,” stated Dr. Tutton. Individually, radiofrequency ablation (RFA) and vertebral augmentation both have proven data, which demonstrates a reduction in cancer-related pain as well. Dr. Tutton pointed out, “The combination of the two has not been studied well, and that is one of our tasks is to study the combination of ablation and augmentation.”
There are a few companies with ablation devices. “The Star™ (DFINE, Inc., San Jose, CA) system “… has the ability to articulate in the vertebral body,” stated Dr. Tutton. Furthermore, in a study of 92 patients with malignant spinal lesions, the Star™ system allowed “RFA treatment of previously untreatable lesions with resultant reduction in pain that was not controlled by systemic or radiation therapy.”1 DFINE has announced a multicenter clinical trial to review RF ablation and vertebral augmentation in patients with osseous cancer.
Dr. Tutton reiterated that the most important concept to remember is all patients, and all fractures are different; one device is not going to be appropriate for all.
- Implants are beginning to enter the US market.
- The Kiva® is the first FDA-approved device with Level I data.
- Vexim’s SpineJack® potentially could be next, as the company has announced plans for a multicenter trial.
- Device studies need to demonstrate good outcome data with reduction in adjacent level fractures and, potentially reduced readmission and reintervention rates.
Sean Tutton, MD, FSIR is a consultant for Benvenue Medical, Inc.