Testing of Motion-Preserving Implants Covered in New Standard
A new ASTM International standard provides testing procedures for devices that can be used to treat spinal disorders while allowing for continued joint movement. The standard, F2624, Test Method for Static, Dynamic and Wear Assessment of Extra-Discal Spinal Motion-Preserving Implants, was developed by Subcommittee F04.25 on Spinal Devices, part of ASTM International Committee F04 on Medical and Surgical Materials and Devices. Medical device development engineers working on flexible spinal fixation systems will be the primary users of F2624.
According to Brad Estes, Orthopaedic Bioengineering Laboratories, Duke University Medical Center, and F04 member, the last several years have seen an escalating interest in motion-preserving devices for the treatment of spinal disorders such as advanced degenerative disc disease. While certain treatments, such as fusing the spinal motion segment with rigid stainless steel or titanium screw-and-rod systems, have proven to be effective, there is some evidence that the resulting change in local stiffness and kinematics can potentially translate into accelerating disc degeneration at an adjacent level.
“An extra-discal motion-preserving implant system seeks to address this issue by replacing a rigid rod system with some type of flexible member, which will maintain a degree of load transmission and motion across the degenerated spinal segment or segments,” says Estes. “The central premise of these types of systems is that they offer some directional stability, which can alleviate pain while still allowing motion across the joint.”
Estes says that all interested parties are welcome to participate in the standards developing activities of Subcommittee F04.25. “We’re always looking for individuals interested in spinal device standards,” Estes says.
Technical Information: Brad Estes, Orthopaedic Bioengineering Laboratories, Duke University Medical Center, Durham, N.C.
ASTM Staff: Daniel Schultz