Bare Minimum
These reports are “just the bare minimum,” said Agarwal. “For example, tissue necrosis – or metallosis due to wear – is present in almost all cases with MAGEC,” but these cases aren’t reported because of “absence of clinical symptoms.”
Agarwal called these MAGEC-related complications “very worrisome.”
“Every single failure of rod fracture or noninvasive distraction mechanism failure in MAGEC leads to another open surgery. And with each surgery, the risk of other complications, such as infection, goes up very significantly,” he said.
He added that the failure of the distraction of the growth rods reduces the overall efficacy of the device.
“Newer studies even question if there is a real quality-of-life difference with use of MAGEC rods over the myriad of other options,” he said.
He stressed the need for better technical and clinical controls to avoid such adverse events – for example, more frequent use of minimum distraction.
The researchers also retrieved MAUDE data on the top five failures associated with standard instrumentation used in spinal fusion. These included pedicle screw breakage post surgery (336 reports), set screw damage during surgery (257), rod breakage post surgery (175), interbody cage breakage during surgery (118), and pedicle screw breakage during surgery (75).
The rates of adverse events involving the MAGEC rods, which are used in relatively rare surgical procedures, “seem high” in comparison, said Agarwal.
Commenting for Medscape Medical News, Lee Tan, MD, assistant professor of neurologic surgery, University of California, San Francisco, praised the authors for conducting an “interesting” study on the complications and mode of failure related to MAGEC rods in scoliosis correction using a large database.
“They identified distraction mechanism failure and pedicle screw breakage as the most common device-related complication and standard instrumentation-related complication, respectively,” said Tan.
“This is very useful information during patient education and preoperative counseling. It also identifies the areas for improvement and innovation on this important topic. I commend the authors for their excellent work,” he said.
The study received no funding. Agarwal has received royalties from and consults for Spinal Balance and is an editorial board member for Clinical Spine Surgery and Spine.
This article first appeared on Medscape.com.