Manufacturers of dynamic spine stabilization systems may be sent back to the proverbial drawing board to improve their devices after a recent Food and Drug Administration (FDA) injunction ordered them to conduct new studies to insure the safety of their products. The FDA ordered the manufacturers to conduct post-market surveillance studies to monitor fusion rates and other possible safety issues related to the stabilization products. The FDA order also requires manufacturers to gather pre-market clinical data on not-yet-released products. The order may result in labeling changes on future devices.
The FDA’s concern arose due to a lack of substantial clinical data to show how well the devices in question provide support for complete spinal fusions. Their concern is that there is not enough data to conclusively demonstrate that the devices are strong enough. The FDA worries that the dynamic stabilization systems may loosen, break, or bend under pressure over time. If the devices do happen to be faulty, spinal injury patients would be at great risk of suffering additional injuries and may require further surgical procedures. The FDA order does not affect the methods by which the stabilization devices are employed.
Older conventional spinal stabilization systems consist of screws and metal rods anchored into the spine during bone fusion spinal surgeries. Dynamic systems are different. They employ flexible polymer cords, springs, and movable screw heads to allow patients the freedom to bend and rotate their spine, which the conventional systems do not.
The FDA order insists that post-market studies investigate: the rate of fusion in the dynamic systems compared to traditional rigid systems; details, rates, and severity of any side effects, also compared to rigid systems; additional surgeries and types of surgeries required for dynamic systems vs. the rigid models; and finally, any and all causes of failure of any systems leading to a surgical removal of the devices from patients’ spines.
Since bone fusion devices are classified as class II devices in FDA labeling regulations, newer-model devices are allowed to be developed and manufactured if they are demonstrated to be substantially equivalent to predecessor devices already approved on the market.
Dynamic stabilization systems first received approval from the FDA in 1997, and they will likely continue to be used in the future. The FDA mandate promises to improve the effectiveness and safety of such devices.
(pic from drsharma.ca)