NuVasive, Inc.’s MAGEC Rod, a winner of the Orthopedics This Week Best Technology in Spine awards in 2011, was and remains one of the more important innovations in the treatment of early onset scoliosis.
Developed by California-based Ellipse Technologies, Inc., the system uses magnetically expandable rods to correct moderate to severe scoliotic spine curvature. Because the rods are expandable in situ using magnets, as the patients grow, the rods can be adjusted without additional surgery. Not only does this reduce the trauma of repeated surgeries, it reduces costs.
In situ rod expansion is not a new concept. In 2004, Jean Dubousset, M.D., a reknown spine surgeon, and Arnaud Souberian, a French medical engineer, developed and used a magnetic rod known as the Phenix device which, itself, was derived from an expandable rod for bone tumors.
The first information about Ellipse’s MAGEC rod was presented by Akbarnia in 2009 wherein he described an implantable magnetic rod which could be distracted by external, non-surgical device. Three years later, Akbarnia published data on Yucatan pigs which showed distraction was possible at a rate of 7mm/week for 7 weeks using an external adjustment device. The researchers found that they could achieve 80% distraction non-surgically.
Akbarnia later presented data from a multicenter study of 33 patients which documented the ability of the MAGEC rods to successfully improve Cobb angles 46% and 48%, respectively, in single and dual rods, respectively. Dannawi, in 2013, found that using MAGEC instrumentation in 34 children (mean age 8 years) with early onset scoliosis delivered statistically significant improvement in mean pre-operative, immediate post-operative and final cobb angles and also significant increase in the mean T1-S1 distance.
Other researchers, notably La Rosa et al, Ridderbusch et al and Yılmaz et al also documented outcomes using MAGEC and reported that it was efficacious in allowing noninvasive distraction without repeat surgeries and that it achieved spinal growth comparable to conventional growth rod techniques.
In 2016, NuVasive acquired Ellipse and the MAGEC rod technology for $410 million.
