Treating Scoliosis with Tethering: New Study Data

New research from Rady Children’s Hospital, San Diego, California has determined that anterior spinal growth tethering surgery results in an ongoing reduction in adolescent idiopathic scoliosis (AIS). Their study, ”Rate of Scoliosis Correction After Anterior Spinal Growth Tethering for Idiopathic Scoliosis,” appears in the September 15, 2021, edition of The Journal of Bone and Joint Surgery.

Co-author Peter O. Newton, M.D., chief of the Division of Orthopedics & Scoliosis and surgeon-in-chief at Rady Children’s Hospital-San Diego, explained to OTW, that there has been increasing interest in the use of anterior vertebral tethering as a treatment for idiopathic scoliosis.  “The indications particularly with regards to the remaining overall growth of the patient and the extent to which that growth will translate into growth modulating correction of the vertebra themselves (reducing the scoliosis) in the years after surgery has been controversial to say the least.”

The researchers performed a retrospective chart and radiograph review of procedures performed between 2012 and 2016 (with at least two years of follow-up). They determined each segment’s screw angulation rate of change (degrees per month) and each patient’s height velocity (centimeters per month) between each of the visits (3 to 12 visits per patients). The investigator divided the visits into four groups according to postop duration (<1 year, 1 to 2 years, >2 to 3 years, >3 years).

“The most important finding here,” stated Dr. Newton to OTW, “is that, in fact, that remaining growth does result in continued scoliosis correction proving that growth modulation is possible. This has been seen clearly in experimental animal models but seeing measurable progressive reduction in scoliosis that persist for years after tethering surgery when performed in a young enough patient is critical information.”
“We now have data to begin to better predict the outcomes of tethering surgery for patient with 2-3 years of growth remaining. Identifying the ‘sweet spot’ about the growth remaining and the scoliosis correction required (based on preoperative and immediate postoperative measures) may now be possible. Patient with smaller curves, but substantial growth can now be delayed (or potentially under corrected at the time of surgery) based on these data on segmental rates of scoliosis correction. Similarly, patients with insufficient growth to provide meaningful growth modulation may be identified and another method of treatment recommended.”