Locked Lateral Plating Versus Retrograde Nailing for Distal Femur Fractures: A Multicenter Randomized Trial

Relative contribution of the nail and plate to a nail-plate construct for comminuted distal femoral fractures

The purpose of this study was to assess the biomechanical contributions of the nail and the plate individually to a complete nail-plate construct in the setting of comminuted distal femur fractures. For this biomechanical study, comminuted extra-articular distal femur fractures were created in 24 synthetic osteoporotic femur models. These were then split into three groups: the nail-only group, the plate-only group, and the nail-plate group. After fixation, each specimen underwent sequential axial and torsional loading, and axial and torsional stiffness were calculated and compared. The addition of a nail to a plate-only construct increased axial stiffness by 19.7% and torsional stiffness by 59.4%. The plate-only group and nail-plate group both demonstrated significantly greater axial and torsional stiffness than the nail-only group at all levels of axial and torsional load. (p < 0.001) At 1000 and 2000 N of cyclic loading, the nail-plate group demonstrated significantly greater axial stiffness than the plate-only group (p ≤ 0.018). The nail-plate group demonstrated greater torsional stiffness than the plate-only groups at all levels of torsional loading (p < 0.001). In osteoporotic comminuted distal femur fracture models, most of the axial stiffness in a nail-plate construct comes from the plate. While the combination of the two constructs is not fully additive, the plate contributes the majority of the axial and torsional stiffness in a nail-plate construct. The supplementation of the plate with a nail primarily helps to increase resistance to rotational forces. Level of Evidence: III.

Outcomes of Distal Third Femur Fractures in Patients 18 Years and Older: A Pilot Study

INTRODUCTION

The selection of the most optimal fixation method for fractures of the distal femur, whether intramedullary nail (NL), lateral locking plate (PL), or nail/plate (NP) is not always clear. This study retrospectively evaluates surgical patients with distal femur fractures and introduces a pilot study using cluster analysis to identify the most optimal fracture fixation method for a given fracture type.

METHODS

This is a retrospective cohort study of patients 18 years and older with an isolated distal femur fracture who presented to our Level-1 trauma center between January 1, 2012, and December 31, 2022, and obtained NL, PL, or NP implants. Patients with polytrauma and those without at least six months of follow-up were excluded. A chart review was used to obtain demographics, fracture classification, fixation method, and postoperative complications. A cluster analysis was performed. The following factors were used to determine a successful outcome: ambulatory status pre-injury and 6-12 months postoperatively, infection, non-union, mortality, and implant failure.

RESULTS

A total of 169 patients met inclusion criteria. No statistically significant association between the fracture classification and fixation type with overall outcome was found. However, patients treated with an NP (n = 14) had a success rate of 92.9% vs only a 68.1% success rate in those treated with a PL (n = 116) (p = 0.106). The most notable findings in the cluster analysis (15 total clusters) included transverse extraarticular fractures demonstrating 100% success if treated with NP (n = 6), 50% success with NL (n=2), and 78.57% success with PL fixation (n=14). NP constructs in complete articular fractures demonstrated success in 100% of patients (n = 5), whereas 77.78% of patients treated with NL (n = 9) and 61.36% of those treated with PL (n = 44).

CONCLUSIONS

Plate fixation was the predominant fixation method used for distal third femur fractures regardless of fracture classification. However, NP constructs trended towards improved success rates, especially in complete intraarticular and transverse extraarticular fractures, suggesting the potential benefit of additional fixation with these fractures. Cluster analysis provided a heuristic way of creating patient profiles in patients with distal third femur fractures. However, a larger cohort study is needed to corroborate these findings to ultimately develop a clinical decision-making tool that also accounts for patient specific characteristics.

Retrograde Intramedullary Nailing Versus Locked Plating for Extreme Distal Periprosthetic Femur Fractures: A Multicenter Retrospective Cohort Study

OBJECTIVES

To compare clinical and radiographic outcomes after retrograde intramedullary nailing (rIMN) versus locked plating (LP) of "extreme distal" periprosthetic femur fractures, defined as those that contact or extend distal to the anterior flange.

METHODS

DESIGN

Retrospective review.

SETTING

Eight academic level I trauma centers.

PATIENT SELECTION CRITERIA

Adult patients with periprosthetic distal femur fractures at or distal to the anterior flange (OTA/AO 33B-C[VB1]) treated with rIMN or LP.

OUTCOME MEASURES AND COMPARISONS

The primary outcome was reoperation to promote healing or to treat infection (reoperation for elective removal of symptomatic hardware was excluded from this analysis). Secondary outcomes included nonunion, delayed union, fixation failure, infection, overall reoperation rate, distal femoral alignment, and ambulatory status at final follow-up. Outcomes were compared between patients treated with rIMN or LP.

RESULTS

Seventy-one patients treated with rIMN and 224 patients treated with LP were included. The rIMN group had fewer points of fixation in the distal segment (rIMN: 3.5 ± 1.1 vs. LP: 6.0 ± 1.1, P < 0.001) and more patients who were allowed to weight-bear as tolerated immediately postoperatively (rIMN: 45%; LP: 9%, P < 0.01). Reoperation to promote union and/or treat infection was 8% in the rIMN group and 16% in the LP group ( P = 0.122). There were no significant differences in nonunion ( P > 0.999), delayed union ( P = 0.079), fixation failure ( P > 0.999), infection ( P = 0.084), or overall reoperation rate ( P > 0.999). Significantly more patients in the rIMN group were ambulatory without assistive devices at final follow-up (rIMN: 35%, LP: 18%, P = 0.008).

CONCLUSIONS

rIMN of extreme distal periprosthetic femur fractures has similar complication rates compared with LP, with a possible advantage of earlier return to weight-bearing. Surgeons can consider this treatment strategy in all fractures with stable implants and amenable prosthesis geometry, even extreme distal fractures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Which fixation produces the best outcome for distal femoral fractures? Meta-analysis and systematic review of retrograde nailing versus distal femoral plating in 2432 patients and 33 studies

PURPOSE

The distal femur comprises a wide intramedullary cavity and thin cortical bone. Firm internal fixation of comminuted fractures with displacement is challenging. Although many comparative studies have reported retrograde intramedullary nailing (RIN) and distal femoral plating (DFP) as the usual fixation methods for distal femoral fractures, no clear conclusion has been reached. Therefore, a meta-analysis and systematic review of the clinical and radiological results were conducted to determine the appropriate treatment method for distal femoral fractures.

METHODS

A systematic search of the PubMed, Embase, Scopus, and Cochrane Library databases from their inception to December 19, 2022, was performed using predefined criteria. Studies comparing the effects of RIN and DFP were considered. The analyzed outcome measures included duration of surgery, blood loss, time to union, delayed union, nonunion, malalignment, implant failure, infection, reoperation, limb length discrepancy, range of motion, persistent anterior knee pain, knee stiffness, and functional scores. Meta-analysis of pooled data was conducted using a random-effects model to determine the standard mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Thirty-three studies with 2,432 patients were included. Compared to DFP, RIN was associated with a shorter time to fracture union (SMD, 1.83 months; 95% CI - 2.76 to - 0.90; P < 0.001) and a lower incidence of postoperative infection (OR 0.54; 95% CI 0.31-0.94; P = 0.03). Pooled analysis revealed no significant differences in other outcome measures between the two treatment modalities.

CONCLUSION

In distal femoral fractures, RIN had a shorter bone union time and was more resistant to infection than DFP. However, there were no significant differences in the other clinical parameters. Therefore, the characteristics, strengths, and weaknesses of RIN and DFP should be carefully identified, and appropriate treatment should be provided based on the patient's medical condition and fracture pattern.

Nail Plate Combination Fixation Versus Lateral Locked Plating for Distal Femur Fractures: A Multicenter Experience

OBJECTIVES

To (1) report on clinical, radiographic, and functional outcomes after nail-plate fixation (NPF) of distal femur fractures and (2) compare outcomes after NPF with a propensity matched cohort of fractures treated with single precontoured lateral locking plates.

DESIGN

Multicenter retrospective cohort study.

SETTING

Ten Level 1 trauma centers.

PATIENTS/PARTICIPANTS

Patients with OTA/AO 33A or 33C fractures.

INTERVENTION

Fixation with (1) retrograde intramedullary nail combined with lateral locking plate (n = 33) or (2) single precontoured lateral locking plate alone (n = 867).

MAIN OUTCOME MEASUREMENTS

The main outcomes of interest were all-cause unplanned reoperation and presence of varus collapse at final follow-up.

RESULTS

One nail-plate patient underwent unplanned reoperation excluding infection and 2 underwent reoperation for infection at an average of 57 weeks after surgery. No nail-plate patients required unplanned reoperation to promote union and none exhibited varus collapse. More than 90% were ambulatory with no or minimal pain at final follow-up. In comparison, 7 of the 30 matched lateral locked plating patients underwent all-cause unplanned reoperation excluding infection (23% vs. 3%, P = 0.023), and an additional 3 lateral locked plating patients were found to have varus collapse on final radiographs (10% vs. 0%, P = 0.069).

CONCLUSIONS

Despite a high proportion of high-energy, open, and comminuted fractures, no NPF patients underwent unplanned reoperation to promote union or demonstrated varus collapse. Propensity score matched analysis revealed significantly lower rates of nonunion for NPF compared with lateral locked plating alone. Larger studies are needed to identify which distal femur fracture patients would most benefit from NPF.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Using a Traction Table for Fracture Reduction during Minimally Invasive Plate Osteosynthesis (MIPO) of Distal Femoral Fractures Provides Anatomical Alignment

INTRODUCTION

Fracture reduction and fixation of distal femur fractures are technically demanding. Postoperative malalignment is still commonly reported after minimally invasive plate osteosynthesis (MIPO). We evaluated the postoperative alignment after MIPO using a traction table with a dedicated femoral support.

METHODS

The study included 32 patients aged 65 years or older with distal femur fractures of all AO/OTA types 32 (c) and 33 (except 33 B3 and C3) and peri-implant fractures with stable implants. Internal fixation was achieved with MIPO using a bridge-plating construct. Bilateral computed tomography (CT) scans of the entire femur were performed postoperatively, and measurements of the uninjured contralateral side defined anatomical alignment. Due to incomplete CT scans or excessively distorted femoral anatomy, seven patients were excluded from analyses.

RESULTS

Fracture reduction and fixation on the traction table provided excellent postoperative alignment. Only one of the 25 patients had a rotational malalignment of more than 15° (18°).

CONCLUSIONS

The surgical setup for MIPO of distal femur fractures on a traction table with a dedicated femoral support facilitated reduction and fixation, resulting in a low rate of postoperative malalignment, despite a high rate of peri-implant fractures, and could be recommended for surgical treatment of distal femur fractures.