In previous research, Agarwal had written that using “shorter distraction magnitude at shorter intervals” could mitigate MAGEC complications coming from excessive, remote distraction force.
Agarwal explained, “Distraction forces cause the rods to fracture, but are also necessary to achieve the objective of the surgery, that is height gain in children. The solution that occurred to our team was gradual distraction of the growth rods, instead of maximum possible distractions. With traditional dual growth rods, changing the frequency of distraction is not an option, but with the use of MAGEC (MAGnetic Expansion Control, Nuvasive) it is feasible. We found in our study that frequent distractions with smaller distraction forces will induce much lower stresses in the rods. This is a fact and has remained consistent with our ongoing studies with FDA and other collaborative research work.”
MAGEC Is the Only Ethical Device for Early Onset Scoliosis
In Agarwal’s view, in situ or other forms of non-surgical distraction techniques instead of repeated surgeries is the only ethical choice for treating children with early onset scoliosis when the best treatment option is spine distraction. Traditional growth rods (which require repeated surgeries in order to adjust for the patients growth) are still commonly used in countries with limited resources. In Agarwal’s opinion, traditional growth rods should be replaced with either MAGEC, guided growth techniques (SHILLA), vertebral tethering, or hybrid techniques like active apex correction or spring distraction systems.
Other Researchers Chime In – and Create New Controversy
In 2017, European Spine Journal published a study called “Rod fracture and lengthening intervals in traditional growing rods: is there a relationship?,” by Pooria Hosseini, M.D., M.Sc.; Jeff B. Pawelek; Stacie Nguyen; George H. Thompson; Suken A. Shah; John M. Flynn; John P. Dormans; Behrooz A. Akbarnia; and Growing Spine Study Group.
The authors cited the previous work of Agarwal and his colleagues. Which started the controversy.
When Agarwal read the 2017 European Spine Journal study, he took strong exception to some of the study’s conclusions. He wrote a letter to the editor saying, in part, “We read with great interest the article by Hosseini et al., published in the European Spine Journal…The article was well written but their interpretation of our work was erroneous.”
“We highlighted the importance of shorter intervals of distraction, with low magnitudes of distraction forces, as a way to reduce stresses on the rods. This reduction in stresses would in turn reduce the propensity of rod breakage, which are very often seen with growth rod constructs. They [Pooria Hosseini et al] however, presented a correlation between the ‘different distraction intervals’ and the ‘incidences of rod breakage,’ without factoring in the actual magnitude of forces that were applied during the procedures. Their conclusion mistakenly assumes that the distractions simulated by us were of same magnitudes, and only differed in the interval of application. This misunderstanding deters further research into using shorter intervals.”
