A magnetically controlled growing rod (the Magec System, Ellipse Technologies) may be a non-invasive alternative to standard growth rod techniques, according to a preliminary study presented by Behrooz Akbarnia at the 18th International Meeting on Advanced Spinal Techniques (IMAST, 13-16th July, Copenhagen, Denmark).
In early onset scoliosis, growth rod techniques are used to correct deformity while allowing the spine to continue to grow. With standard rods, frequent surgery, to lengthen the rod, is required over many years. While growth rods are an effective treatment, the repeated surgery increases the risk of complications. However, the magnetically controlled growing rod is implanted via minimally invasive surgery and subsequently lengthened, non–invasively, by changing the magnetic field through the skin.
In a multicentre prospective review, Akbarnia et al looked at the early clinical and radiographic data of a growing rod. After a mean follow up of nine months, the average distraction achieved was 4.2mm per patient. There were no major complications, with no neurologic deficit or implant failure; the complications that were observed included superficial infection in one patient, prominent implant in another, and minimal loss of initial length in three index surgeries.
There was also partial loss of distraction in 14 of the 68 distractions, but this loss was regained in subsequent distractions. Akbarnia et al concluded: “Preliminary results indicate that the magnetically controlled growth rod appears to be safe and provides distraction comparable with standard growth rod procedure without the need for repeated surgeries.”
In an Ellipse Technologies press statement, Behrooz Akbarnia, clinical professor of orthopaedics at the University of California San Diego, said: “Ellipse has developed a truly remarkable technology that will dramatically advance the treatment of spinal deformity and significantly improve the otherwise traumatic experience these children currently endure. The Magec System has exceeded my expectations of what I had hoped to someday witness during my clinical research career.”
The Magec System has CE certification in Europe but not, at present, in the USA.