Clinical comment

Distal femoral fractures have been reported to go onto nonunion at a rate of 6–24%.^1–3 Nonunions have been demonstrated to have devastating consequences for patients’ physical, psychosocial, and financial wellbeing as well as lead to significant healthcare system costs.^4–6 Additionally, mechanical failure (often contributory to nonunion) has been identified as a significant problem in distal femoral fractures, resulting in the need for re‐operation in 4% of cases.⁷ With this in mind, the surgical techniques used to fix distal femoral fractures should attempt to minimize the nonunion rate and requirement for re‐operation.

Available literature and quality of the evidence

A 2015 Cochrane review by Griffin et al. (level II) for distal femoral fractures included six studies examining surgical fixation methods, including preliminary data from two studies that compared locking plates versus intramedullary (IM) nailing and the dynamic condylar screw (DCS), respectively.⁸ No differences were found between locking plates and other interventions in this review in terms of union rates or mechanical failures. Similarly, a small randomized controlled trial (RCT) (level II) by the Canadian Orthopaedic Trauma Society of 52 patients with distal femoral fractures were randomized to either locked plating with the Less Invasive Stabilization System (LISS) or DCS.⁹ Significantly more DCS patients achieved bony union without subsequent intervention in comparison to LISS plating.

A meta‐analysis (level II) by Koso et al. synthesized the results of 11 level II and 3 distal femoral fracture studies including 505 patients.⁷ They found no significant differences in nonunion rates, reoperation rates, or mechanical failures when comparing plating constructs versus IM nails – they did not differentiate between locking and nonlocking plates. The LISS was compared specifically to other constructs, which included IM nails, other locking plates, DCS, and nonlocking plate constructs and was found to have significantly fewer mechanical failures.

The Southeast Fracture Consortium compared locking compression plating to LISS for distal femoral fixation in a retrospective review (level III) of 339 patients.¹⁰ No significant difference was found between the two constructs for mechanical failure or nonunion rates.

Findings

Based on the current available evidence, it is unclear if locking plates provide any benefit over other constructs. This is especially apparent as the predominant locking plate option reported on in the literature is the LISS, which is no longer as widely used with the advent of other commercial locking plates that are marketed as less rigid to avoid nonunion.^9,11 There is a need for high‐quality evidence examining the optimal fixation method for distal femoral fractures.

Resolution of clinical scenario

• Level II and III evidence provides mixed results for the benefit of locking plates over other constructs for distal femoral fractures. Given the current literature, no resolution was reached.