Impact of Surrounding Canal Size on Time to Union After Intramedullary Nailing of Femur Fractures: Are 10-mm Nails All We Need?

Abstract

Objective: To determine whether intramedullary nail (IMN) size and its relation to the canal diameter [nail-canal (NC) diameter] impacts the union rate or time to union in the treatment of femoral shaft fractures. Design: Retrospective review. Setting: Two Level 1 and 1 Level 2 trauma centers. Patients: Two hundred eighty-seven patients met the criteria and were included in the study. Intervention: Patients were treated with either an antegrade or retrograde IMN. Comparisons were first performed comparing 10- versus 11- versus 13-mm nails. Patients were then divided into 3 groups based on the difference between the size of the femoral canal at the isthmus and the IMN (NC diameter). Group 1: <1.0 mm, group 2: >1.0 and <2.0 mm, and group 3: >2.0 mm. Main Outcome Measurements: Nonunion rates, mean time to union. Results: Two hundred eighty-seven patients with a minimum of 12-month follow-up, who were treated with size with IMN for femoral shaft fractures, were assessed for fracture characteristics, time to union, and union rate. When comparing IMN size, no statistical difference was found when comparing time to union or overall union rate. When comparing NC diameter, no significant difference was found in union rate and time to union when comparing between the groups. Conclusion: Similar rate of union and time to union were exhibited regardless of nail size or NC diameter. This can correlate to the standard utilization of a reamed, titanium 10-mm IMN with 5.0-mm interlocking screws in the treatment of femoral shaft fractures, offering potentially less reaming, shorter operative times, and removing unnecessary stock from inventory. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Periprosthetic Supracondylar Femoral Fractures Above a Total Knee Replacement: An Updated Compatibility and Technique Guide for Fixation With a Retrograde Intramedullary Nail

“…The literature has also shown no difference in time to union or rate to union in femoral shaft fractures treated with a reamed 10-mm nail versus larger sized nails. 19 As outlined above, retrograde femoral nailing of these challenging fractures can often aid in the postoperative rehabilitation by allowing early weight-bearing and aid in the recovery to baseline. [16][17][18]…”

Extracorporeal measurement of femoral nail length in the treatment of trochanteric hip fractures: the “box” technique

“…A recent retrospective study showed 10 mm nails to be of adequate strength, regardless of femoral canal length, to promote healing in 147 patients with femoral shaft fractures. [ 24 ] The use of 10 mm diameter nails has also obviated the need for reaming the canal in trochanteric fractures, with no significant difference in perioperative and postoperative outcomes compared with reamed nailing in 37 patients. [ 25 ] There were no cases of anterior cortical penetration in the unreamed group.…”

Does matching degree matter for proximal femoral intramedullary nail on reoperation rate in intertrochanteric fractures?

“…The gap between the intramedullary nail and the femoral medullary cavity was equal to the difference in diameter between the two, and all patients were divided into three groups according to the gap: high-matching group: gap ≤ 2 mm; middle-matching group: 2 < gap < 4 mm; and low-matching group: gap ≥ 4 mm. The grouping method was based on the experience of Richard et al [19] and the actual situation of this cohort study.…”