Medical Device Daily Associate
In the past, mixing bone cement for repairing back bone compression fractures has often required complicated cement mixing equipment, and exposure of the operating room (OR) staff to toxic monomers resulting in the delivery of inconsistent cement mixing results.
Now ArthroCare (Austin, Texas) has received FDA 510(k) clearance to market its Parallax acrylic resin cartridge with Tracers that works with the Parallax integrated delivery system (IDS), which ArthroCare acquired via its $28 million acquisition of Parallax (Scotts Valley, California) in 2004 (Medical Device Daily, Feb. 2, 2004).
The company said the Parallax IDS is the industry's first fully-enclosed device used to mix and deliver bone cement during vertebroplasty and kyphoplasty procedures.
“The Parallax integrated delivery system brings consistency, simplicity and a new level of performance to vertebroplasty procedures,“ said David Applegate, vice president and general manager of ArthroCare Spine (Sunnyvale, California).
“What we're giving physicians is something that can work in a variety of situations that they encounter,“ Parallax Product Manager Jennifer George told Medical Device Daily.
Vertebroplasty has been used for more than 10 years in the U.S. to treat painful vertebral compression fractures, which can result from severe osteoporosis or benign (hemangioma) or malignant lesions (metastatic cancers, myleoma). The company estimated that more than 750,000 people per year suffer from vertebral compression fractures.
Typically, vertebroplasty is performed under fluoroscopic guidance using a standard set of tools that include acrylic bone cement, a cement delivery system and access needles. Currently, cement is prepared, poured into the delivery system and then injected into the vertebrae through a properly positioned needle, filling the spaces within the bone. The cement then hardens and stabilizes the vertebrae.
In contrast, the Parallax system uses a self-contained cement cartridge containing precise amounts of monomer and polymer, and a mating reservoir.
The cement cartridge locks into the Parallax IDS reservoir and, through a plunging motion, it fills the reservoir with cement in a consistent fashion so that it is ready for injection.
In addition to simplifying the cement mixing process, the Parallax IDS also provides precise cement volume control; a large cement reservoir that allows a vertebroplasty to be completed without refilling; and a 17-inch injection tube that minimizes the operator's exposure to radiation.
“Parallax's new cement delivery system for vertebroplasty is impressive,“ said Jason Stoane, MD, a neuroradiologist at St. Joseph Hospital (Bellingham, Washington). “A completely closed mixing system that provides consistency and excellent cement visualization is important for procedure safety and outcomes. In addition, the price of the system makes the product advancements even more appealing.“
The company also touted the fact that the self-contained tube also allows the cement to remain sterile prior to use.
“At no point do you touch that cement,“ said George. “From the time it comes out of the package to when it's injected into the body, no one is touching it.“
George described the development of the cartridge as a “labor of love,“ noting that the FDA wanted to make sure that the bone cement delivered via the cartridge was consistent and that no toxic monomers could come out of the tube.
“There concern was 'in what way does the cartridge change the formula?'“ said George. “We really had to do extensive testing to show them that what you get out of that tube is equivalent to what you're going to get out if you mix it in a vial.“
She said the delivery system also had to be modified from an existing system that AthroCare acquired when it bought Parallax two years ago, changing the bottom part of the system by removing a handle that was previously there and replacing it with the mixing cartridge.
The company plans to market the new delivery system to both orthopedic surgeons and interventional radiologists, though George said the primary user will most likely be the latter group.
She noted that the system is a single-use product which is recommended for use on 1 1/2 levels of the spine, depending on how large the vertebrae are.
With modifications of this technology, George said there is potential for the delivery system and cartridge to be used in other orthopedic applications.
“All you're doing is containing the cement, mixing, making that consistent to whether that be in hips or knees or other parts of the body.“