Alternative Treatment Speeds Up Limb Lengthening

A specialized procedure that lengthens bones can also prevent amputations in selected patients who have suffered severe fractures, according to Loyola University Medical Center orthopedic surgeon Mitchell Bernstein, M.D.

Bernstein, is first author of a study, published in the journal Clinical Orthopaedics and Related Research. He reports that an alternative limb-lengthening technique makes the long recovery process less cumbersome, shortening it from 11 to 7 months. The story was reported by Newswise of Maywood, Illinois.

In standard limb-lengthening procedures, surgeons encase patients in a rigid frame made of steel and aluminum, called a “fixator.” The device contains three rings that surgeons place around the lower leg and secure them to the bone. This allows for manipulation of bone fragments with stainless steel pins.

Bernstein’s study examined an alternative technique that involved placing a titanium rod in the body in conjunction with the external fixer. Newswise reported that, “The alternative technique significantly reduced the amount of time patients had to spend in the external fixator.”

Limb lengthening works on the principle of distraction osteogenesis.

Four times a day, the external fixator pulls apart bone segments, and new bone tissue grows to fill the gap. Bone so treated lengthens at a rate of about 1mm. per day. According to Bernstein, bones can be lengthened by between 15% and 25% of their original length.

Once the new bone tissue is formed, it remains too fragile to bear any weight. It still takes several months for bone to fully regenerate. In the traditional bone-lengthening technique the patient stays in the external fixator until the bone is mature and strong enough to support the weight of the body.

In the alternative technique, the surgeon implants the titanium rod inside the bone to strengthen it and reduce the amount of time the patient must spend in the external fixator.

The Hospital for Special Surgery conducted the study. Fifty eight patients underwent limb lengthening. Thirty patients received the standard procedure and 28 received the alternative technique, which combined the external fixator with the titanium rod implantation. The average limb lengthening for both groups was 2.1 inches. There was no difference in the number of complications between the two groups and all patients had good to excellent results. The senior author of the study was Robert Rozbruch, M.D., of the Hospital for Special Surgery in New York.