NEWS | August 14, 2012

UC Davis, Shriners to study using magnets to correct "sunken chest"

Investigational device corrects chest deformity the way braces correct teeth.


UC Davis Children's Hospital and Shriners Hospitals for Children-Northern California have embarked on a groundbreaking study of a device that uses magnets to correct sunken chest, the most common congenital chest-wall abnormality, in the same way that orthodontic braces correct teeth.

Diana Farmer Diana Farmer

Sunken chest is a deformity of the cartilage that connects the ribs to the breastbone. The deformed cartilage pulls the breastbone inward, giving the chest a caved in or sunken appearance. The condition occurs in about one in 800 children born in the United States each year and is three times more common among boys than girls.

The clinical study will test the safety and efficacy of an investigational device called the "magnetic mini-mover" and is being led at UC Davis by Professor and Chair of the Department of Surgery Diana Farmer in the UC Davis School of Medicine. The study is being led at Shriners by Gary Raff, associate professor of pediatric cardiac surgery at UC Davis and a consulting member of the medical staff at Shriners.

"At an academic medical center we're always thinking about ways of doing things better," said Farmer, who is a pediatric surgeon. "Our mission is broader than just providing the best possible clinical care," Farmer said. "We constantly try to improve on the clinical care and train the next generation of doctors to do this as well."

Pectus excavatum traditionally has been corrected through major surgical reconstruction of the chest wall. The procedures that are involved are extensive and require hospitalization and careful pain management. 

The new minimally invasive investigational procedure involves placing a surgically embedded magnet just under the skin on the surface of the patient's breastbone during an outpatient visit. The patient can return home on the day of the procedure with minimal discomfort.

The titanium-encased internal magnet is about the size of a quarter. A second magnet housed in a specially designed brace is worn outside the chest in a device called the magnetic mini-mover. The device creates a constant magnetic force field that applies a controlled, consistent pull on the magnet on the sternum, pulling the breastbone outward to correct the deformity. The patient wears the brace for three to 12 months, depending on the severity of their deformity. 

Some patients also suffer serious emotional difficulties and low self-esteem because the condition often worsens during adolescence, when young people are especially concerned about their physical appearance, Farmer said. 

The magnetic mini-mover procedure was developed and the multi-center clinical trial initiated by pediatric surgeon Michael R. Harrison at UC San Francisco. UC Davis and Shriners are collaborating with UCSF in the study, which will enroll children and adolescents between 8 and 14 years of age for 18 to 24 months at UC Davis, Shriners and UCSF.

The research is funded by the Pediatric Device Consortium and the Food and Drug Administration.

UC Davis Children's Hospital is the Sacramento region's only nationally ranked, comprehensive hospital for children, serving infants, children, adolescents and young adults with primary, subspecialty and critical care. It includes the Central Valley's only pediatric emergency department and Level I pediatric trauma center, which offers the highest level of care for critically ill children. The 129-bed children's hospital includes the state-of-the-art 49-bed neonatal and 24-bed pediatric intensive care and pediatric cardiac intensive care units. With more than 120 physicians in 33 subspecialties, UC Davis Children's Hospital has more than 74,000 clinic and hospital visits and 13,000 emergency department visits each year. For more information, visit