Session V - Knee / Tibia / Pediatrics


Fri., 10/15/10 Knee, Tibia & Pediatrics, Paper #60, 4:21 pm OTA-2010

A Comparison of Locked versus Non-Locked Enders Rods for Length-Unstable Pediatric Femoral Shaft Fractures

Henry B. Ellis, MD1; Christine A. Ho, MD2; David A. Podeszwa, MD2; Philip L. Wilson, MD2;
1University of Texas Southwestern, Dallas, Texas, USA;
2Texas Scottish Rite Hospital, Dallas, Texas, USA

Purpose: Stainless steel flexible Enders rods have been used for intramedullary fixation of pediatric femur fractures with good success. However, despite intraoperative anatomic alignment, length-unstable femur fractures can present postoperatively with fracture shortening or malrotation. The purpose of this study was to review all length-unstable pediatric femoral shaft fractures in which Enders rods were used and compare those that were locked to those that were not locked. Our hypothesis was that locked Enders rods would maintain length, alignment, and rotation of length-unstable pediatric femoral shaft fractures.

Methods: We conducted a retrospective clinical and radiographic review of all patients at a single institution undergoing flexible intramedullary rodding for a length-unstable femoral shaft fracture from 2001 to 2008. A length-unstable fracture was defined as either a comminuted or a spiral fracture longer than twice the diameter of the femoral shaft. 107 length-unstable femoral shaft fractures fixed with Enders rods were identified, of which 37 cases (35%) had both Enders rods locked through the eyelet in the distal femur with a 2.7-mm fully threaded, cortical screw. Patient demographics, clinical course, complications, fracture characteristics, and radiographic outcome were compared for the locked and nonlocked groups.

Results: There were no statistically significant differences between the groups for demographic data, operative variables, fracture pattern, fracture location, time to union, femoral alignment, or major complications. Shortening of the femur, defined as the change in distance of the distal end of the rod from its intraoperative position to that measured at 6 weeks postoperatively, was significantly greater for the nonlocked cases. The medial and lateral locked Enders rods moved 1.3 and 1.9 mm, respectively, and the unlocked Enders each moved 12.1 mm (P < 0.05). There was no clinical or radiographic evidence of screw breakage, pull-out, loosening, or plowing in the metaphysis. At final follow-up, there were significantly more (P < 0.05) clinical complaints in the nonlocked group, including complaints of limp, gross malrotation, clinical shortening, and palpable painful rods.

Conclusions: Locking Enders rods for length-unstable pediatric fractures is an excellent option to prevent shortening and possibly malrotation of these inherently unstable fractures. In this study, locking the Enders rods resulted in no additional complications, added surgical time, or increased blood loss.


Alphabetical Disclosure Listing (292K PDF)

• The FDA has not cleared this drug and/or medical device for the use described in this presentation   (i.e., the drug or medical device is being discussed for an “off label” use).  ◆FDA information not available at time of printing. Δ OTA Grant.