Biodegradable implant to help heal broken bones

Washington: A plastic derived from corn starch combined with a volcanic ash compound could help heal the bones of hundreds of thousands of patients with orthopaedic injuries who need bone replacement, scientists, including one of Indian-origin, have found.

The biodegradable polymer, reinforced with Montmorillonite clay nanoparticles for strength, dissolves in the body within 18 months. As the material dissolves, new bone formation takes its place.

The material is created by injecting the polymer-clay mixture with carbon dioxide, resulting in an implant that looks like foam, but is rigid like bone.

Researchers at the Beaumont Hospital - Royal Oak in US designed the bone material to be porous, just like actual human bone.

Traditional bone graft procedures require surgeons to remove bone from another part of the patient's body to heal the affected area and encourage new bone growth.

Harvesting a patient's bone can result in complications at the harvest site, researchers said.

Some surgeons also use bone donated from cadavers. However, there is a limited supply of donor bones available.

Using a synthetic material will likely lead to a reduction in the surgery complication rate. The patient will only need to heal from one surgery because harvesting bone would not be necessary.

The goal is to use the material without any additional permanent hardware placed in a patient's body. Current procedures often require a metal or non-resorbable plastic implant because traditional bone grafts are not strong enough without the added support.

"This improves outcomes for the patient because internal hardware can pose a challenge with respect to being a potential site for infection, and can complicate MRI and CT imaging tests," said Kevin Baker, director, Beaumont Orthopaedic Research Laboratories.

"In addition, from the surgeon's perspective, not having to worry about a large piece of metal or hard plastic in the area may make future procedures easier," said Baker, who worked on the study with Rangaramanujam Kannan, of Johns Hopkins, formerly with Wayne State University.

The finding was published in the journal Nanomedicine.