Background: Intramedullary nailing of the femur without reaming of
the medullary canal has been advocated as a method to reduce marrow
embolization to the lungs and the rate of infection after open fractures. The
use of nailing without reaming, however, has been associated with lower rates
of fracture-healing. The purpose of this prospective study was to compare the
rate of union of femoral shaft fractures following intramedullary nailing with
and without reaming.
Methods: Two hundred and twenty-four patients were enrolled in a
multicenter, prospective, randomized clinical trial to compare nailing without
reaming and nailing with reaming. One hundred and six patients with 107
femoral shaft fractures were treated with a smaller diameter nail without
reaming of the canal, and 118 patients with 121 fractures had reaming of the
canal and insertion of a relatively larger diameter nail. Patients were
followed at six-week intervals until union occurred or a nonunion was
Results: The two groups were comparable with regard to the measured
patient and injury characteristics. Eight (7.5%) of the 107 fractures in the
group without reaming had a nonunion compared with two (1.7%) of 121 fractures
in the group with reaming (p = 0.049). The relative risk of nonunion was 4.5
times greater (95% confidence interval = 1 to 20) without reaming and with use
of a relatively small-diameter nail.
Conclusion: Intramedullary nailing of femoral shaft fractures
without reaming results in a significantly higher rate of nonunion compared
with intramedullary nailing with reaming.
Level of Evidence: Therapeutic study, Level I-1a
(randomized controlled trial [significant difference]). See Instructions to
Authors for a complete description of levels of evidence.