Gladstone Native Becomes First U.S. Surgeon to Implant Dynamic Spine

Understanding Early-Onset Scoliosis and the Need for the SDS Implant

Early-onset scoliosis is a complex three-dimensional curvature of the spine that can severely threaten a child’s life if left untreated. According to a 2022 report by the device’s inventors and researchers, the condition can cause progressive thoracic insufficiency and respiratory failure, ultimately leading to death, making early intervention critical. Traditional treatments often required frequent surgeries that raised concerns about mental development from repeated anesthesia, while magnetically-controlled growing rods carried a high complication rate requiring revision surgery in nearly half of patients after two years. To solve this, René Marten Castelein and Moyo Chikondi Kruyt, professors at the University Medical Center Utrecht, designed the SDS to control spinal deformity while allowing the spine to grow naturally with the child without extra clinic visits just for adjustments.

Engineering and Regulatory Path to FDA Clearance

The development of the SDS began in Utrecht in 2015 when a six-year-old patient faced life-threatening scoliosis caused by a thoracolumbar fusion mass with no approved alternatives available. Under Dutch and European medical device law, a non-CE-marked implant may be used for an individual patient when no approved alternative exists and health is at stake, according to Cresco, the company founded by Castelein and Kruyt. The device utilizes compressed helical springs fitting around cobalt chrome rods, affixed via titanium pedicle screws and sliding on polyethylene-lined connectors to maintain uninterrupted spinal growth. Following clinical studies with informed parental consent, the Netherlands patented the device in 2017, and the U.S. filed for it in 2020. After receiving FDA Breakthrough Device designation, two additional years of engineering and regulatory work led to its 510(k) clearance, as announced by Cresco.

Historic First U.S. Surgery at Scottish Rite for Children

Kingston Brown, a six-year-old patient at Scottish Rite for Children with neuromuscular scoliosis and spinal muscular atrophy (SMA)—a genetic condition causing progressive muscle weakness—became the first American patient to receive the SDS. Dr. McIntosh noted that while the new elements involved the Cresco spring device and its tensioning instruments, much of the surgery felt familiar. The care team selected the SDS to provide continuous gentle spinal correction, reducing the care burden while helping preserve the child’s sitting balance, comfort, and respiratory function, as detailed in a June article published by Scottish Rite for Children. Chief of Staff Dr. Daniel J. Sucato stated that the innovation reflects the hospital’s commitment to advancing pediatric orthopedic care and improving patient outcomes.

Frequently Asked Questions

What is the Spring Distraction System (SDS)?

The SDS is a dynamic growth-friendly medical implant designed to control spinal deformity in children with early-onset scoliosis while allowing the spine to grow naturally without requiring frequent surgical adjustments.

Who invented the SDS implant?

The device was invented by René Marten Castelein, professor emeritus of orthopedic surgery and pediatric orthopedics, and Moyo Chikondi Kruyt, professor of reconstructive skeletal engineering, both at the University Medical Center Utrecht in the Netherlands.

Where was the first U.S. surgery performed?

Dr. Amy L. McIntosh performed the first U.S. implantation of the SDS at Scottish Rite for Children in Dallas, Texas, on a six-year-old patient named Kingston Brown.

When did the FDA clear the device?

The FDA granted 510(k) clearance to the Spring Distraction System on January 19, 2026, declaring it safe and effective for use in the United States.