Lower difference in femoral version seen with trochanteric nails vs retrograde, piriformis nails

SAN DIEGO — Use of trochanteric entry femoral nails for intramedullary nailing of femoral shaft fractures showed a significantly lower revision rate and difference in postoperative femoral version between the uninjured and operative limb compared with the use of piriformis and retrograde entry nails, according to results presented here.

“Overall, all three nail entry types are reliable in achieving low difference in femoral version,” Richard S. Yoon, MD, said in his presentation at the Orthopaedic Trauma Association Annual Meeting. “The likelihood is that even though significant difference of trochanteric nails having a lower difference, it probably has no clinical impact.”

Yoon and colleagues enrolled 316 patients with unilateral femoral shaft fractures and compared the outcomes of patients treated with trochanteric, piriformis and retrograde entry nails. The primary study outcome was the postoperative difference in femoral version, and the secondary outcome was revision rate.

Univariate analysis showed patients in the piriformis cohort had a mean postoperative difference in femoral version of 9.5 and patients in the retrograde cohort had a mean difference of 9.4. However, Yoon noted the trochanteric cohort had a mean postoperative difference in femoral version of 7.9. The investigators also found that a lower BMI correlated with a lower difference in femoral version.

“We compared the difference of femoral version between the cohorts and found that trochanteric entry nails had a significantly lower difference in femoral version,” Yoon said.

Results showed nine patients in the piriformis group and three in the retrograde group underwent revision. All of the patients who underwent revision in the piriformis group and two patients in the retrograde group were revised for malrotation. According to Yoon, patients with open fractures “had a significant impact and tended to have a lower revision rate.”

“Zero patients were revised in the trochanteric entry group, and this was statistically significant,” he said. “[Looking] at our revisions for malrotation, the mean difference in the piriformis group was 22° and in the retrograde about 19°. For the revisions, the distal fragment was most commonly malrotated.” — by Casey Tingle

Reference:

Yoon RS, et al. Paper #75. Presented at: Orthopaedic Trauma Association Annual Meeting. Oct. 7-10, 2015; San Diego.

Disclosure: Yoon reports no relevant financial disclosures.