One of the most common problems in pediatric orthopaedic surgery is that many procedures involve the placement of temporary hardware to stabilize fractured bones. This metal hardware often is removed after the bone has healed in order to prevent additional problems as pediatric and adolescent patients age. Nails and screws can impede correct skeletal growth and may even protrude under the skin, leading to deformity or pain. Removal involves subjecting patients to an additional surgery, with its attendant risks and difficulties, including those associated with anesthesia and exposure to nosocomial infections.

Magnesium nail in porcine humerus with fracture

In June 2016, Kevin Little, MD, director of the Pediatric Hand and Upper Extremity Center at Cincinnati Children’s, began working to develop a biomaterial solution to this problem – essentially, a type of nail that wouldn’t need to be removed. Along with his team, he has discovered that magnesium is ideal for this purpose because it is biodegradable and it has been shown to aid nerve regeneration as it biodegrades. Additional studies at other institutions have demonstrated that magnesium can promote bone healing.

In order to test the durability of the magnesium nails, his team has been placing them in porcine bone. Part of the National Science Foundation (NSF) grant under which they work has studied methods of growing magnesium as a single crystal, which translates to a stronger, more durable material. This is important because even though the hardware used in pediatric orthopaedic surgery need not be as rigid as that used in adult fixations, it must still be able to keep the healing bone stable.

The work underway is truly a team effort, with staff from orthopaedics, physiology and engineering collaborating to tackle the question of whether magnesium is – or can be made to be – strong enough to be used in pediatric orthopaedic surgery.

Clinical use of this technology in children is at least a decade away, says Little. However, he looks forward to seeing resorbable magnesium nails in widespread use. “They will make a phenomenal impact on our patients’ lives by limiting the amount of surgery they need and by reducing the amount of time missed from school, activities and sports – and they will lower the cost of healthcare delivery as well.”