Named after the Titans — a group of powerful Ancient Greek gods — the element titanium is known for its strength and resistance to corrosion. Titanium and titanium alloys are used in a wide variety of applications, from the mundane, such as in house paint, to more exotic uses, like in propellers and rotor blades, and in high-speed spy planes.
Titanium’s strength, as well as its excellent biocompatibility, is also integral to a device that is changing the lives of children with a debilitating rare disease, offering hope of drastically improved outcomes.
Invented by The Children’s Hospital of Philadelphia’s Robert M. Campbell, MD, the vertical expandable prosthetic titanium rib (VEPTR) is the first device approved by the FDA to treat thoracic insufficiency syndrome (TIS), a rare congenital condition affecting children in which the thorax cannot support regular growth or breathing. By separating the ribs and helping to straighten the spine, the VEPTR is designed to give children’s lungs to grow, allowing them to breathe without the aid of ventilators.
The founder and Director of Children’s Hospital’s Center for Thoracic Insufficiency Syndrome, as well as a Professor of Orthopaedic Surgery at the University of Pennsylvania’s Perelman School of Medicine, Dr. Campbell came to CHOP in 2008 from the University of Texas Health Science Center in San Antonio, where he held the President’s Council Chair in Pediatric Orthopaedic Surgery. A highly accomplished pediatric orthopaedic surgeon, Dr. Campbell has been working to improve outcomes for TIS patients for more than 25 years.
Left untreated, TIS can be devastating. As children with TIS grow, the condition causes the chest become deformed, and children with TIS are often born with scoliosis, or curvature of the spine. TIS can lead to death due to respiratory insufficiency. However, since Dr. Campbell implanted the first VEPTR in 1989, the device — which as its name implies can be expanded as the child grows — has proven to be a lifesaver.
Indeed, a recent Journal of Pediatric Orthopaedics study showed the VEPTR gives children with Jeune syndrome, a condition related to TIS, a chance not just to survive, but also to grow and thrive. The study, which Dr. Campbell led alongside colleagues from Texas, found VEPTR treatment improved Jeune syndrome patients’ survival dramatically compared to natural history untreated.
A very rare disease, Jeune syndrome — or asphyxiating thoracic dystrophy — affects approximately 1 in 100,000 infants each year. A multisystem, congenital disorder, Jeune syndrome is characterized by distinctive narrow, bell-shaped chest, shortened limbs, and at times polydactylism. Those born with Jeune syndrome experience breathing problems, and can develop renal, hepatic, and cardiac issues. The chest hypoplasia caused by Jeune syndrome results in severe TIS.
In the Journal of Pediatric Orthopaedics paper, Dr. Campbell and colleagues describe the use of VEPTR to treat 24 patients with Jeune syndrome, at an average of 23 months of age. Of those, two were lost to follow-up, and 17 had a minimum of two years of follow-up examinations. In all, the survival rate of the 22 patients was 68 percent, with less dependence on ventilators.
“This study is, to our knowledge, the largest of the surgical treatment of Jeune syndrome with long-term follow-up, and we are especially excited that the survival rate after surgery was nearly 70 percent, compared to a 70 to 80 percent mortality rate for untreated Jeune syndrome patients, and most were weaned off their ventilators,” said Dr. Campbell.
The procedure “flips” the survival curve,” the researchers note, “and greatly improves quality of life by diminishing the need for oxygen support, CPAP, and ventilator support for these children.”
In addition to the dramatic about-face in survival rate, the researchers also noted VEPTR treatment increased total chest diameter, thoracic spine height, and lumbar spine height. Assisted ventilation rating scores— which Dr. Campbell and his team used to measure pulmonary function — improved in many of the patients, with several who had been entirely dependent on a ventilator before surgery weaned off after treatment.
And Dr. Campbell’s Journal of Pediatric Orthopaedics study is hardly the only promising research that makes use of the VEPTR. A quick search of PubMed reveals a host of VEPTR-related papers, including 27 since the beginning of 2013.
“New advances in surgery occur frequently, but only the test of time can show their true worth at long term follow-up,” Dr. Campbell added. “The VEPTR techniques appear to be living up to their promise.”
To learn more about the vertical expandable prosthetic titanium rib, thoracic insufficiency syndrome, and to read inspiring patient stories, see Children’s Hospital’s Center for Thoracic Insufficiency Syndrome.