Flexible rods found safe, effective for femoral shaft fractures in younger children

Should flexible intramedullary fixation for femoral shaft fractures be offered to parents of children as young as 3 years old?

That question was addressed by Joseph P. Davey, MD, in a study presented at the POSNA Annual Meeting that compared the efficacy and safety of two treatment modalities: flexible rods and the spica cast.

Flexible intramedullary fixation is an option in treating femoral shaft fractures in children older than 5 years of age. (See cover story, “AAOS releases first pediatric clinical practice guidelines.”) “When surgical treatment is offered as an option, parents will generally choose it rather than having their child in a spica cast,” Dr. Davey said.

Flexible rods vs spica casts
The retrospective, matched-control study compared younger children treated with flexible rods or spica casts from 2003 to 2006.

The study group included 26 patients treated with intramedullary fixation (Fig 1). The control group comprised 23 children who received immediate spica casting.

Children from each group were matched by age (within 2 months) and fracture pattern (short oblique, long oblique, or transverse). Because exact matches could not be found for all patients, three patients in the control group were each matched to two different patients in the study group.

Patients in both groups were approximately the same age (4.6 years), but boys dominated the control group (82 percent).

The chart review of each patient focused on demographics, complications, technique, and 1-year follow up. Radiographs were reviewed to determine degree of angulation and shortening.

“When we looked at angulation, we saw that flexible rods were quite effective. On average, we didn’t see shortening as a problem,” said Dr. Davey. “In the spica cast group, however, we did find angulation and shortening issues (Table 1).

“The acceptable position at healing is considered within 15 degrees in the coronal plane, within 30 degrees of the sagittal plane, and with less than 2.0 cm of shortening,” he continued.

Based on that definition, 38 per-cent of the patients treated with spica cast had unacceptable alignment compared to no patients treated with flexible rods (p<0.0001).>

No complications were reported for either group. None of the patients in the surgical treatment group had to return to the operating room or experienced severe skin irritations, infections, hardware migration, or prominence.

Although some studies have shown complications in school-aged children treated with flexible rods, the lack of complications in this study, according to Dr. Davey, is due to the use of large flexible nails (3.5 mm) relative to the patient’s body size and the surgical technique—the exposed distal tips of the rods were left minimally prominent.

How young is too young?
Based on this data, Dr. Davey believes that surgical treatment for femoral shaft fractures can be offered to parents of children younger than 6 years old, but how much younger has yet to be determined.

“The gold standard is still the spica cast and the results from casting are very good,” he said. “What our study demonstrated was a statistically significant difference between the groups. We have yet to determine how important that difference really is.

“If we are going to offer surgical treatment to parents, it has to provide a real benefit. The process has to be easier for the family—allowing children to walk and return to their normal activities more quickly.”

He hopes to do a prospective study to determine how these two treatments affect the family. “If both parents are working and the child is in a spica cast, it’s just as difficult if the child is 4 years old as it would be if the child is 7 or 8 years old. “The new clinical practice guidelines on the treatment of pediatric diaphyseal femur fractures are based on the best evidence available and do point out that further study is needed in this younger group of patients. The benefits may not be as great, but we still need to ask the questions to find those answers,” Dr. Davey concluded.

Coauthors for “Treatment of femoral shaft fractures in young children: Spica cast or flexible rods” included Mac E. Moore, MD, and James L. Wood.

Dr. Davey reported no conflicts of interest for himself or other authors.

Annie Hayashi is the senior science writer for AAOS Now. She can be reached at hayashi@aaos.org

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