Researchers in Hong Kong have shown that a rod that lengthens under magnetic control can effectively treat the spinal curvature seen in children with scoliosis. The approach is much less invasive than existing rod-based therapies, which require repeated invasive surgeries and hospitalization every six months. The magnetically controlled growing rod can be adjusted in outpatient visits, minimizing scarring, pain, time away from school, and burden on parents (because they have to take less time off from work).
The spine of scoliosis patients grows crooked, sometimes appearing to have an S-curve or C-curve from the back. Severe cases can lead to disfigurement and breathing problems if left untreated. In the study published in The Lancet last week, five patients had the magnetically controlled growing rods surgically implanted and affixed to their spines and then underwent monthly outpatient adjustments. During the adjustments, a doctor places a handheld magnetic remote control on the patient’s back. The remote engages a rotating and lengthening mechanism in the rod. Adjustments take less than 30 seconds, say the authors.
The rod system is marketed by a California company called Ellipse Technologies, but the tests were conducted at the Duchess of Kent Children’s Hospital in Hong Kong. Two of the patients have had the titanium rods for as long as two years, and both show positive results so far, although more time is needed before the experimental treatment can be compared to standard therapies.
In an accompanying commentary, spinal deformity experts John Smith of the University of Utah School of Medicine and Robert Campbell of the Children’s Hospital of Philadelphia described the results of the two patients, ages five and 12 at the time of surgery, as encouraging, although they cautioned that more follow-up is required. They note that issues of device migration, breakage, or infection have yet to be addressed. What I found most interesting was their comment on the restrictive barriers to performing the tests in the U.S. In their own words:
“Magnetically controlled growing-rod technology is being developed outside the USA, where, in our view, the pathway to develop and test new technology faces excessive barriers (growing rods remain unapproved by the US Food and Drug Administration). If this technology was available in the USA, we believe that it would be rapidly used to avoid repetitive surgeries and improve quality of life for children with spinal deformity. We strongly encourage [first author] Cheung and colleagues to continue to report their results—both positive outcomes and adverse events. We are hopeful that further development of the technology will make this treatment increasingly available to children worldwide.