University of Rochester

Bone Growth and Development by the Numbers

May 16, 2000

A grant from the Whitaker Foundation will help a University of Rochester engineer learn more about how our bones grow, develop, and heal.

Amy Lerner, assistant professor of mechanical engineering, will use a New Investigator Award of $210,000 from the foundation for a three-year study of the role of mechanical forces in bone growth. These forces affect the health of many children, including those with cerebral palsy, where muscles pull on bones abnormally and can cause discomfort, arthritis, or deformities. "Doctors often perform surgery to alter the mechanics of a joint, knowing that if they correct the mechanics, the problem will correct itself," says Lerner. "But right now the rules that govern the relationship between mechanics and bone growth aren't well known; doctors with all the training available have to take a trial-and-error approach. We hope to produce information that surgeons can use to harness the relationship between mechanics and bone growth more fully."

Mechanical forces may also play a role in determining why some people remain bow-legged all their lives, instead of outgrowing the condition as most children do. The research should also help physicians understand why broken bones sometimes heal incorrectly.

Much of Lerner's work involves developing sophisticated computer models known as finite-element models to quantify stresses and strains. Those models are central to another project she conducts with Saara Totterman, professor of radiology, and a team of students: understanding the mechanics of the knee joint. A tough wedge of tissue called the meniscus is responsible for spreading out the forces where two of our major leg bones, the femur and the tibia, come together inside the knee. Tearing the meniscus is a common injury for athletes, and Lerner is studying the different types of tears and their effects on the forces transmitted through the knee. The information should help surgeons predict how to better customize treatment; many patients today have arthritis because the standard treatment years ago was removal of the meniscus.

Lerner earned bachelor's degrees at Cornell University and the University of Delaware and her doctorate in mechanical engineering at the University of Michigan before joining the University in 1997. She is one of several faculty members at the core of a growing biomedical engineering program on campus.