Supplementation of Lateral Locked Plating for Distal Femur Fractures: A Biomechanical Study

Double plating is a suitable option for periprosthetic distal femur fracture compared to single plate fixation and distal femoral arthroplasty

Aims

The purpose of this study was to compare reoperation and revision rates of double plating (DP), single plating using a lateral locking plate (SP), or distal femoral arthroplasty (DFA) for the treatment of periprosthetic distal femur fractures (PDFFs).

Methods

All patients with PDFF primarily treated with DP, SP, or DFA between 2008 and 2022 at a university teaching hospital were included in this retrospective cohort study. The primary outcome was revision surgery for failure following DP, SP, or DFA. Secondary outcome measures included any reoperation, length of hospital stay, and mortality. All basic demographic and relevant implant and injury details were collected. Radiological analysis included fracture classification and evaluation of metaphyseal and medial comminution.

Results

A total of 111 PDFFs (111 patients, median age 82 years (interquartile range (IQR) 75 to 88), 86% female) with 32 (29%) Su classification 1, 37 (34%) Su 2, and 40 (37%) Su 3 fractures were included. The median follow-up was 2.5 years (IQR 1.2 to 5.0). DP, SP, and DFA were used in 15, 66, and 30 patients, respectively. Compared to SP, patients treated with DP were more likely to have metaphyseal comminution (47% vs 14%; p = 0.009), to be low fractures (47% vs 11%; p = 0.009), and to be anatomically reduced (100% vs 71%; p = 0.030). Patients selected for DFA displayed comparable amounts of medial/metaphyseal comminution as those who underwent DP. At a minimum follow-up of two years, revision surgery for failure was performed in 11 (9.9%) cases at a median of five months (IQR 2 to 9): 0 DP patients (0%), 9 SP (14%), and 2 DFA (6.7%) (p = 0.249).

Conclusion

Using a strategy of DP fixation in fractures, where the fracture was low but there was enough distal bone to accommodate locking screws, and where there is metaphyseal comminution, resulted in equivalent survival free from revision or reoperation compared to DFA and SP fixation.

The linked nail/plate construct for the management of distal femur fractures in the elderly

BACKGROUND

Distal femoral fractures represent a challenging injury, with many different factors such as the method of fixation, complexity of fracture pattern, and patient co-morbidities affecting the outcome. Lots of surgical treatment options have been described, but recently double construct fixation, using a nail/plate combination, has received lots of attention, a technique that leads to faster weight-bearing, low risk of metalwork failure, and non-union. The purpose of this study was to investigate the effectiveness of the linked nail/plate construct in the management of complex distal femur fractures and to investigate if the above technique leads to faster recovery and earlier radiographic union.

MATERIALS AND METHODS

In total 15 cases were included in the study, that underwent a combined nail/plate construct for a distal femur fracture between January 2021 and December 2022. Only cases with a linked nail/plate construct were included, with a minimum follow-up of 1 year. Open femur fractures, single implant fixation cases, and revision procedures were excluded.

RESULTS

In this cohort study, 11 cases were periprosthetic distal femur features, and 4 cases were distal femur fractures around a native knee joint. The mean age group was 74 years, 86.6% of the patients had a BMI > 25 and the mean time to fracture union was 24 weeks (range from 20 to 26 weeks). All cases healed uneventfully and the complication rate was 6.6%, including 1 case of superficial infection which resolved completely with oral antibiotics.

CONCLUSION

The increasing age population, the complexity of distal femoral fractures along with the increasing physiological demands of the elderly population, drive the need for double fixation constructs that allow early mobilization and enhance fracture stability. In our study, the linked nail/plate construct seems to provide adequate stability and excellent union rates (100%) with no associated increased risk of complications.

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.

Risk of reverse golf club deformity with medial plating of distal femur fracture

INTRODUCTION

This study described a deformity induced by medial plating of supracondylar distal femur fractures using plates that are precontoured for other anatomic locations.

MATERIALS AND METHODS

OTA/AO 33A fractures were created in 12 sawbone femurs and fixed with either a proximal humerus locking plate (PH), an ipsilateral lateral tibial plateau plate (LTP), or an ipsilateral medial distal tibial plate (MDT). A motion capture system measured changes in length and rotation of the distal femur as the plate was applied. Each plate underwent four trials and the mean and standard deviation (SD) for each measurement was reported. An analysis of variance with post hoc Tukey test compared malreduction measures between plate types.

RESULTS

All plates consistently created a varus deformity. There was lateral lengthening with a compensatory medial shortening and an increase in the lateral distal femoral angle. The distal fracture fragment was laterally translated, and internally rotated. The PH plate had significantly greater lateral length (27.39 mm SD 4.78, p = 0.007), shorter medial length (13.57 mm SD 4.99, p = 0.028), greater lateral translation (28.82 mm SD 5.70, p = 0.010) and greater widening of the lateral distal femoral angle (28.54° SD 4.98, p < 0.001) than the LTP and MDT plates. The MDT plate had significantly greater angulation anteriorly (8.40° SD 1.07, p < 0.001) and laterally (7.63° SD 3.10, p = 0.002) than the PH and LTP plates. There was no significant difference between plates in internal rotation (PH: 3.07° SD 2.79; LTP: 2.05° SD 1.05; MDT 3.81° SD 3.56; p = 0.659).

CONCLUSION

When dual plating supracondylar distal femur fractures, poor plate positioning and a mismatch between plate contour and the slope of the medial distal femur can lead to varus angulation, internal rotation, and lateral translation or a "reverse golf club deformity". After comparing three types of precontoured plates, the authors recommend initial evaluation of the ipsilateral proximal tibial plate when placing a plate along the medial distal femur.

LEVEL OF EVIDENCE

IV.

Comparison of radiological and functional results in osteoporotic distal femur fractures operated with single plating, lateral incision, and double plating, anterior paramedial incision: A retrospective study

Treatment of osteoporotic distal femur fractures is often complicated by a high rate of nonunion and varus collapse. For such fractures, lateral plating with lateral incision and double plating with anterior paramedial incision have shown promising results in the recent literature. The hypothesis of this study was that bilateral plating of comminuted distal femur fractures in osteoporotic patients would result in higher union rates and lower revision rates compared to an isolated lateral locking plate. The study included 56 patients (23 males, 33 females) with supracondylar femur fracture. According to the OA/OTA classification, 9 were type A3, 8 were A2, 13 were C1, 16 were C2, and 10 were C3. The mean follow-up period was 12 months, with 29 patients treated using lateral mini-incision, lateral locking plate, and 27 patients treated with anterior paramedial incision, dual plating. The clinical and radiological results were evaluated. The mean duration of radiological union in the studied population was 15 ± 2.1 months (range, 11-21 months) in the single plate group (Group A), and 13.5 ± 2.6 months (range, 9-19 months) in the double plate group (Group B). Mean ROM was 112.3° and flexion contracture 4° in Group A, and ROM 108.3° and flexion contracture 6.7° in Group B. (P = .15). The average Western Ontario and McMaster Universities Arthritis Index (WOMAC) score was 85.6 points in Group A and 83.5 points in Group B (P = .2278). The postoperative anteversion measurement in the operated extremity ranged from -15 to 19 in Group A, and from 5 to 18 in Group B. When the anteversion degrees were compared between the injured and uninjured extremities in the postoperative period, a significant difference was observed within Group A (P = .0018), but no significant difference was observed in Group B (P = .2492). Dual plate fixation using the anterior paramedial approach is an effective operative method for osteoporotic distal femur fractures. This has many advantages such as precise exposure, easy manipulation, anatomic reduction, and stable fixation. However, for surgical indications and medial bone defects > 1 cm, grafting should be performed.

What Is the Likelihood of Union and Frequency of Complications After Parallel Plating and Supplemental Bone Grafting for Resistant Distal Femoral Nonunions?

BACKGROUND

Management of resistant distal femur nonunions is challenging because patients not only have disability from an unhealed fracture, but also often have a shortened femur, stiff knee, deformities, and bone defects to address during revision surgery. Dual plating of the distal femur in such a setting can maintain stability that allows the nonunion to heal while also addressing bone defects and correcting deformities simultaneously. Dual-plating techniques that have been described lack standardization with regard to the size and type of medial-side implants and configuration of the dual-plate construct.

QUESTIONS/PURPOSES

(1) What proportion of patients achieve radiologic evidence of union after parallel plating of resistant distal femoral nonunions? (2) What improvements in function are achieved with this approach, as assessed by improvements in femoral length discrepancy, knee flexion, and patient-reported outcome scores? (3) What complications are associated with the technique?

METHODS

Between 2017 and 2020, the senior author of this study treated 38 patients with resistant distal femoral nonunions, defined here as nonunions that persisted for more than 12 months since the injury despite a minimum of two previous internal fixation procedures. During the study period, our preferred technique for treating aseptic, resistant distal femoral nonunions was to use dual plates in a parallel configuration augmented with autografts. Of 38 patients, three patients with active signs of infection who underwent resection and reconstruction using bone transport techniques and two patients older than 65 years with deficient distal femur bone stock who underwent endoprosthetic reconstruction were excluded. Of the 33 included patients, 67% (22 of 33) were male. The median age was 40 years (range 20 to 67 years). Nonunion was articular and metaphyseal in 13 patients and metaphyseal only in 20 patients. Our surgical approach was to remove existing implants, perform intraoperative culturing to rule out infection, debride the nonunion, correct the deformity, perform intra-articular and extra-articular lysis of adhesions with quadriceps release, and apply fixation using medial and lateral fixed-angle anatomic locked implants positioned in a parallel configuration. Every attempt to improve length was undertaken, and the defects were filled with autografts. A total of 97% of patients were followed until union occurred (one of 33 was lost to follow-up before union was documented), and 79% (26 of 33) were assessed for functional outcomes at a minimum of 2 years (median 38 months [range 25 to 60 months]) after excluding patients lost to follow-up and those in whom union did not occur after parallel plating. Union was defined as evidence of central trabecular bridging on AP radiographs and posterior cortical bridging on lateral radiographs. These radiologic criteria were defined to overcome difficulties in assessing radiologic healing in patients with lateral and medial plates. With parallel plating, bridging trabecular bone along the posterior cortex on lateral radiographs and the central region on AP radiographs is visualized and can be appreciated and interpreted as evidence of healing in two orthogonal planes. Preoperative and follow-up clinical assessment of knee ROM, the extent of femoral length correction based on calibrated femoral radiographs before and after surgery, and the evaluation of improvement in lower limb function based on the preoperative and follow-up differences in responses to the lower extremity functional scale (LEFS) were studied (the LEFS is scored from 0 to 80, with higher scores representing better function). Complications and secondary surgical procedures to address them were abstracted from a longitudinally maintained trauma database.

RESULTS

Sixty-seven percent (22 of 33) of nonunions showed radiologic healing by 24 weeks, and another 24% (eight of 33) healed by 36 weeks. Six percent (two of 33) did not unite, and one patient was lost to follow-up before union was documented. In the 79% (26 of 33) of patients available for final functional outcome assessment, the median femoral shortening had improved from 2.4 cm (range 0 to 4 cm) to 1.1 cm (range 0 to 2.3 cm; p < 0.001), and the median knee ROM had improved from 70° (range 20° to 110°) to 100° (range 50° to 130°; p = 0.002) after surgery. The median LEFS score improved to 63 (range 41 to 78) compared with 22 (range 15 to 33; p < 0.001) before surgery. Serious complications, including major thromboembolic events, iliac graft site infection, knee stiffness (flexion < 60°), and medial plate impingement necessitating removal, were seen in 30% (10 of 33) of patients. Secondary surgical interventions were performed in 24% (eight of 33) of patients to address procedure-related complications.

CONCLUSION

Based on our findings, a high likelihood of union and improvements in knee and lower limb function can be expected with parallel plating of resistant distal femur nonunions using anatomic locked plates. However, the increased frequency of complications observed in our study suggests the need for improvements in dual-plating techniques and to explore possible alternative fixation methods through larger multicenter comparative studies.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Dual Plate Fixation of Periprosthetic Distal Femur Fractures

OBJECTIVES

Dual implants for distal femur periprosthetic fractures is a growing area of interest for these challenging fractures with dual plating (DP) emerging as a viable construct for these injuries. In the current study, an experience with DP constructs is described.

METHODS

DESIGN

Retrospective case series with comparison group.

SETTING

Level 1 academic trauma center.

PATIENT SELECTION CRITERIA

Adults >50 years old sustaining comminuted OTA/AO 33-A2 or 33-A3 DFPF treated with either DP or a single distal femur locking plating (DFLP). Patients with simple 33-A1 fractures were excluded. Prior to 2018, patients underwent DFLP after which the treatment of choice became DP.

OUTCOME MEASURES AND COMPARISONS

Reoperation rate, alignment, and complications.

RESULTS

34 patients treated with DFLP and 38 with DP met inclusion and follow up criteria. Average follow up was 18.2 ± 13.8 months in the DFLP group and 19.8 ± 16.1 months in the DP group ( P = 0.339). The average patient age in the DFLP group was 74.8 ± 7.3 years compared to 75.9 ± 11.3 years in the DP group. There were no statistical differences in demographics, fracture morphology, loss of reduction, or reoperation for any cause ( P >.05). DP patients were more likely to be weight bearing in the twelve-week postoperative period ( P <0.001) and return to their baseline ambulatory status ( P = 0.004) compared to DFLP patients.

CONCLUSIONS

Dual plating of distal femoral periprosthetic fractures maintained coronal alignment with a low reoperation rate even with immediate weight bearing and these patients regained baseline level of ambulation more reliably as compared to patients treated with a single distal femoral locking plate.

LEVEL OF EVIDENCE

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

Does the type of medial plate fixation matter for supplemental fixation of distal femur fractures manage with a lateral pre-contoured locked plate? A Biomechanical study

INTRODUCTION

Fixation of distal femur fractures with a lateral pre-contoured locking plate provides stable fixation and is the standard treatment in most cases, allowing early range of motion with a high rate of union. However, in situations, the stability achieved with the lateral plate alone may be insufficient, predisposing to fixation failure. The objective of the study was to compare, in synthetic bone models, the biomechanical behaviour of the fixation with a distal femur lateral pre-contoured locking plate solely and associated with a 3.5 mm proximal humeral locking plate applied upside down or a 4.5 mm helical locking compression plate on the medial side.

MATERIAL AND METHODS

A total of 15 solid synthetic left femur samples were used. A metaphysical defect at the level of the medial cortex was simulated. The samples were randomly distributed into three groups equally. All groups received a 4.5/5.0 mm single lateral 9-hole distal femur lateral pre-contoured locking plate. Group 1 had no supplementary plate. Group 2 received a supplementary 6-hole 3.5 mm proximal humeral locking plate and Group 3 received a supplementary 4.5/5.0 mm helical 14-hole narrow locking compression plate.

RESULTS

Both supplementary plate types used in groups 2 and 3 contributed to increase the apparent stiffness of the construct, but pairwise comparison showed statically significant difference only between group 1 and 3. No significant difference was observed between groups 2 and 3.

CONCLUSION

Both supplementary plates might be considered for improving the fixation in distal femur fracture in selected cases.

Retrograde intramedullary nailing or locked plating for stabilisation of distal femoral fractures? A comparative study of 193 patients

PURPOSE

The aim of this study was to evaluate the results of distal femoral fracture fixation of two different methods, lateral locking plate (LP) or an Intra-medullary nail (IMN), in patients managed in our institution. More specifically, to assess: (a) if there was a difference in functional outcomes between the LP and IMN groups; (b) whether the rate of complications was different between the two groups.

METHODS

Between January 2009 and December 2018 adult patients with distal femoral fractures managed in our unit with either LP or IMN for extra and intra-articular fractures were eligible to participate. Demographic details, fracture type, procedures performed, time to union, complications and functional scores (Oxford Knee Score) were recorded and analysed. The mean follow up was 4 years (12-120 months).

RESULTS

Out of 193 patients who met the inclusion criteria, 93 received an IMN whereas 100 patients were treated with LP. Mean age was 64.2 (18-99) and 70.1 (18-100) for the IMN and LP groups respectively. Overall, the two groups had similar demographics and there was no significant difference in the type of fractures sustained (p > 0.05). The Oxford Knee Score was highest for patients fixed with LP, mean 37.3 (6-48, SD 7.3) versus 28.4 (3-48, SD 14.4), (p =  < 0.02) compared to the IMN group. In terms of complications, the rate of non-union was higher in the LP group 8.6% versus 4% in those patients treated with an IMN, p value < 0.01.

CONCLUSION

While the rate of non-union was higher in the LP group and the functional results were superior in the plating group.

Combined nail-plate constructs in the management of osteoporotic native distal femoral fractures: a systematic review of the available evidence

PURPOSE

Distal femoral fractures account for 4-6% of fragility fractures. These may be managed using a combined nail-plate construct (NPC). The use of NPCs is gaining traction. Whilst several theoretical advantages exist, there is little evidence reporting on binary or patient-reported outcomes. The aim of the current study was to perform a systematic review of the available literature pertaining to NPCs and their treatment of native distal femoral fractures, appraising the outcomes and focusing on the rationale for their increasing uptake in recent literature.

METHODS

A comprehensive search of MEDLINE, EMBASE, Clinical Key, PubMed and Cochrane library was performed from date of inception up to in August 9, 2022. All study languages were included initially. A further Google Scholar search review was performed to identify any other studies not identified in the database interrogation. Studies were eligible if they reported on the use of nail-plate constructs in managing distal femoral fractures. Any outcome metric was permitted. The study was conducted in accordance with PRISMA guidelines. Risk of bias was assessed using the Methodological Index for non-randomised Studies tool. Quantitative analysis was performed using a log odds ratio random effects model. The Knapp-Hartung adjustment was utilised if the total number of included studies was < 5. Study effect sizes and appropriate plots were constructed to illustrate the outcomes data.

RESULTS

A total of four studies were eligible for inclusion. Study data was extracted and summarised with their relevant outcomes presented. The literature review demonstrated that the use of NPCs led to significantly earlier full weight bearing (p < 0.001) and had reduced non-union rates over a single construct, without affecting infection rates (12.5% vs. 5.6%; p = 0.289) and significantly lower implant failure rates (10.5% vs. 0%; p = 0.011). A meta-analysis is performed of available studies and Forrest plots presented.

CONCLUSION

The use of NPC in the management of native osteoporotic DFFs is gaining traction but the available evidence is of low grade with significant heterogeneity in small cohorts of patients. We suggest that a large-scale, multicentre prospective study should be performed, with agreed functional and radiological outcome metrics, to provide a more robust evidence base.

Management of distal femoral fractures with metaphyseal and articular comminution (AO/OTA 33C) using nail and plate fixation: a technical note and case series of 14 patients

PURPOSE

To describe the surgical technique and the outcome of a case series of comminuted intra-articular distal femur fractures (AO/OTA 33C) treated with a nail-plate combination (NPC) implant.

METHODS

We retrospectively analyzed a case series of 14 patients with comminuted intra-articular distal femur fractures (DFF) treated with an intramedullary retrograde nail in combination with a lateral low-contact condylar locking plate, in a period between June 2020 and January 2023 at a Level 1 trauma center. Baseline demographic and clinical data were recorded. Time to bone healing, function using Schatzker Lambert Score, and complications were documented.

RESULTS

Fourteen patients, 8 males and 6 females, with a total of 15 NPC implants, were included in this study. Eight out of 14 patients had open fractures, all with a Gustilo Anderson type IIIA exposure. The mean age was 48.5 ± 18.05 years. The median follow-up was 392 days, with only one patient lost to follow-up. 11 out of 15 implants achieved complete radiographic consolidation during follow-up, at a mean of 5.40 ± 1.07 months. At the 12-month follow-up, all patients could fully bear weight painlessly or with mild pain. Schatzker Lambert Score was excellent for 4 patients, good for 2 patients, fair for 5 patients, and failure for 2 patients. The main postoperative complications were rigidity (3 cases), limb shortening (2 cases), and septic non-union (1 case).

CONCLUSION

This study suggests that the nail-plate combination (NPC) may provide a more effective surgical technique for addressing the challenges associated with comminuted intra-articular distal femur fractures (AO/OTA 33C).

LEVEL OF EVIDENCE: 4

Weight-bearing Restrictions after Distal Femur Fractures - Review of Current Literature

The incidence of distal femur fractures increases in the geriatric patient. The primary treatment goal in these fractures is early mobilisation to prevent secondary injuries associated with immobility. In light of the increasing spectrum of therapeutic options for postoperative fracture treatment, including double plating, nail-plate combination and distal femur replacement as postoperative treatments, weight-bearing recommendations are becoming increasingly important. The aim of this study was thus to analyse the weight-bearing recommendations and associated therapy results within the literature of the past 9 years and compare the recommendations to our own approach.

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.

The double-plate fixation technique prevents varus collapse in AO type C3 supra-intercondylar fracture of the distal femur

INTRODUCTION

Varus collapse followed by osteosynthesis for distal femoral fractures with conventional implants has been well documented but is seldom mentioned in fractures managed with locking plates. The purpose of this study was to assess the incidence of varus collapse after treating complex supra-intercondylar fractures of the distal femur (AO type C3) using a Single Plate (SP) or Double Plate (DP) fixation technique.

MATERIALS AND METHODS

We retrospectively reviewed 357 patients with distal femoral fractures who were treated at our hospital between 2006 and 2017. After excluding cases of infection, malignancy, periprosthetic fracture, revision surgery, pediatric fracture, and extra-articular fracture, 54 patients were included in the study. All demographic data and radiological and clinical outcomes were reviewed and analyzed.

RESULTS

There were 54 patients enrolled into this study with age from 15 to 85 years old (mean 41.6, SD = 19.9), and 32 of them were open fractures (59%). The patients were further divided into either an SP (n = 15) or a DP group (n = 39). Demographics, including age, sex, injury severity score, and open fracture type, were all compatible between the two groups. The overall nonunion rate was 25.9% (n = 14; 6 from the SP and 8 from the DP group; p = 0.175). The varus collapse rate was 9.3% (n = 5; 4 from the SP and 1 from the DP group (p = 0.018).

CONCLUSIONS

The varus collapse rate after osteosynthesis with a single lateral locking plate could be as high as 26.7% in AO type C3 fractures of the distal femur, which would be decreased to 2.6% by adding a medial buttress plate. Surgeons should consider DP fixation to avoid varus collapse in severely comminuted complete intra-articular fractures of the distal femur.

Clinical Application of Nail-Plate Fixation in the Treatment of Complex Proximal Third Humeral Fracture: A Case Report and Literature Review

BACKGROUND

Proximal humeral fractures with increasing incidence are common over the past decades. Among them, the complicated and displaced ones, especially combined with the proximal third humeral shaft fractures, need to be treated surgically. Humeral intramedullary nail and locking plate are the most frequently used options. However, few studies address the application of nail-plate combination for management.

CASE PRESENTATION

A 49-year-old man struck by a car was referred to our emergency trauma center. The X-ray and three-dimensional computed tomography (CT) showed a complex proximal humeral fracture with proximal third shaft fracture. No evidence of other associated injuries and neurovascular symptom of the injured left upper limb was shown by physical examination. Nail-plate fixation was performed to restore the anatomic integrity of proximal humerus. The injured arm was maintained in a broad arm sling for 14 days after surgery. The active as well as positive movements under the instruction were encouraged as long as the pain could be tolerated from postoperative day 2. One year after the surgery, the fracture was healed, and the patient regained normal shoulder motion. The good clinical outcomes were obtained by application of nail-plate fixation to treat complex proximal third humeral shaft fractures. Thus, this surgical intervention could be performed as an alternative.

Biomechanical design optimization of distal femur locked plates: A review

Clinical findings, manufacturer instructions, and surgeon's preferences often dictate the implantation of distal femur locked plates (DFLPs), but healing problems and implant failures still persist. Also, most biomechanical researchers compare a particular DFLP configuration to implants like plates and nails. However, this begs the question: Is this specific DFLP configuration biomechanically optimal to encourage early callus formation, reduce bone and implant failure, and minimize bone "stress shielding"? Consequently, it is crucial to optimize, or characterize, the biomechanical performance (stiffness, strength, fracture micro-motion, bone stress, plate stress) of DFLPs influenced by plate variables (geometry, position, material) and screw variables (distribution, size, number, angle, material). Thus, this article reviews 20 years of biomechanical design optimization studies on DFLPs. As such, Google Scholar and PubMed websites were searched for articles in English published since 2000 using the terms "distal femur plates" or "supracondylar femur plates" plus "biomechanics/biomechanical" and "locked/locking," followed by searching article reference lists. Key numerical outcomes and common trends were identified, such as: (a) plate cross-sectional area moment of inertia can be enlarged to lower plate stress at the fracture; (b) plate material has a larger influence on plate stress than plate thickness, buttress screws, and inserts for empty plate holes; (c) screw distribution has a major influence on fracture micro-motion, etc. Recommendations for future work and clinical implications are then provided, such as: (a) simultaneously optimizing fracture micro-motion for early healing, reducing bone and implant stresses to prevent re-injury, lowering "stress shielding" to avoid bone resorption, and ensuring adequate fatigue life; (b) examining alternate non-metallic materials for plates and screws; (c) assessing the influence of condylar screw number, distribution, and angulation, etc. This information can benefit biomedical engineers in designing or evaluating DFLPs, as well as orthopedic surgeons in choosing the best DFLPs for their patients.

Effect of Implant Linkage on Axial and Rotational Stiffness of Nail-Plate Constructs for Comminuted Distal Femoral Fractures

OBJECTIVES

To determine the effect of linking the intramedullary nail and the laterally applied locking plate to treat comminuted distal femur fractures and allow for immediate weight bearing.

METHODS

Comminuted extra-articular distal femur fractures were created in 16 synthetic osteoporotic femurs and split into 2 groups: linked versus unlinked. In the linked construct, in addition to standard plate fixation and proximal locking of the nail, 2 nonthreaded locking bolts (prototypes) were placed through both the plate and the nail. In the unlinked construct, the same number of screws affixed the plate to the bone but were directed around the nail, and separate distal interlocking screws were placed for nail fixation. Each specimen underwent sequential axial and torsional loading, and axial and torsional stiffness were calculated and compared.

RESULTS

On average, the unlinked constructs demonstrated a greater axial stiffness at all levels of axial loading, and linked constructs demonstrated greater average rotational stiffness. However, there were no statistically significant differences ( P > 0.189) between the linked and unlinked groups at any axial or torsional load.

CONCLUSION

In distal femur fractures with metaphyseal comminution, there were no significant differences in axial or torsional stiffness when linking the plate to the nail. Linking the construct seems to provide no significant mechanical advantage compared with the unlinked environment, but it may be a useful strategy to reduce nail "traffic" in the distal segment with no significant disadvantage.

Technical Trick: Supplemental Medial Column Screw Fixation of Distal Femur Fractures Treated With a Laterally Based Locked Plate

SUMMARY

Given known failure rates after lateral plating of distal femur fractures, there is an increasing interest in augmenting fixation to improve outcomes. The addition of medial plates or intramedullary nails have been described with promising results, decreasing nonunion and varus collapse rates. However, the use of dual implants increases implant costs, adds surgical complexity, and requires a second surgical approach that may increase morbidity. A supplemental, percutaneously placed, medial column screw may provide a less invasive means of improving stability and achieving fracture union compared with lateral plating alone.

Orthogonal plating of distal femur fractures: A biomechanical comparison with plate-nail and parallel plating constructs

Purpose

This study compared the biomechanical properties of orthogonal plating with plate-nail and parallel plating constructs for supracondylar distal femur fractures.

Methods

A supracondylar distal femur fracture was simulated using 15 synthetic osteoporotic femurs. Constructs included: (1) plate-nail (lateral locked distal femoral plate + retrograde intramedullary nail); (2) parallel plating (lateral locked distal femoral plate + medial 4.0 mm compression plate); and (3) orthogonal plating (lateral locked distal femoral plate + posterior one-third tubular plate). Specimens underwent nondestructive loading, fatigue loading, and loading to failure. Gapping at the fracture was measured using a three-dimensional motion capture system. Baseline torsional and axial stiffness, stiffness and strain after fatigue loading, and load to failure were determined. A case example of orthogonal plating is also presented.

Results

There was no difference in baseline torsional (p = 0.51) and axial stiffness (p = 0.53). Stiffness after fatigue loading was highest with parallel plating, with no difference between the plate-nail and orthogonal plating constructs (p = 0.84). Strain after fatigue loading was lowest in the parallel plating group (0.54 ± 0.19%), followed by the plate-nail (2.89 ± 0.83%) and orthogonal plating groups (3.04 ± 0.51%).

Conclusion

Orthogonal plating demonstrated comparable baseline stiffness to plate-nail and parallel plating constructs, and similar biomechanical performance in fatigue loading to plate-nail constructs. All specimens had ≤3% strain after fatigue loading, suggesting sufficient stability for fracture healing. The benefits of enhanced stability from dual-implant fixation may be achieved through orthogonal plating while avoiding an additional medial surgical approach, and therefore warrants further investigation as a novel alternative for distal femur fracture fixation.

Nail plate combination in fractures of the distal femur in the elderly: A new paradigm for optimum fixation and early mobilization?

Distal femoral fractures in elderly or osteoporotic patients constitute a challenging injury, especially in the settings of fracture comminution or periprosthetic fractures. A recent trend in the treatment of these difficult injuries is the double fixation with a nail and a plate, a strategy that comes with advantages including faster weight-bearing and lower risk for non-union. Although biomechanical studies have demonstrated the superiority of nail-plate constructs, there is a paucity in the literature regarding the indications and results of treatment. A review of the literature to date was carried out to identify which group of patients would benefit the most from this type of reconstruction and to evaluate the clinical outcomes.

Medial and lateral dual plating of native distal femur fractures: a systematic literature review

Introduction

Lateral locked plating (LLP) development has improved outcomes for distal femur fractures. However, there is still a modest rate of nonunion in fractures treated with LLP alone, with higher nonunion risk in high-energy fractures, intra-articular involvement, poor bone quality, severe comminution, or bone loss. Several recent studies have demonstrated both the safety and the biomechanical advantage of dual medial and lateral plating (DP). The purpose of this study was to evaluate the clinical outcomes of DP for native distal femoral fractures by performing a systematic review of the literature.

Methods

Studies reporting clinical outcomes for DP of native distal femur fractures were identified and systematically reviewed. Publications without full-text manuscripts, those solely involving periprosthetic fractures, or fractures other than distal femur fractures were excluded. Fracture type, mean follow-up, open versus closed fracture, number of bone grafting procedures, nonunion, reoperation rates, and complication data were collected. Methodologic study quality was assessed using the Coleman methodology score.

Results

The initial electronic review and reverse inclusion protocol identified 1484 publications. After removal of duplicates and abstract review to exclude studies that did not discuss clinical treatment of femur fractures with dual plating, 101 potential manuscripts were identified and manually reviewed. After final review, 12 studies were included in this study. There were 199 fractures with average follow-up time of 13.72 months. Unplanned reoperations and nonunion occurred in 19 (8.5%) and 9 (4.5%) cases, respectively. The most frequently reported complications were superficial infection (n = 6, 3%) and deep infection (n = 5, 2.5%) postoperatively. Other complications included delayed union (n = 6, 3%) not requiring additional surgical treatment and knee stiffness in four patients (2%) necessitating manipulation under anesthesia or lysis of adhesions. The average Coleman score was 50.5 (range 13.5-72), suggesting that included studies were of moderate-to-poor quality.

Conclusions

Clinical research interest in DP of distal femoral fractures has markedly increased in the past few decades. The current data suggest that DP of native distal femoral fractures is associated with favorable nonunion and reoperation rates compared with previously published rates associated with LLP alone. In the current review, DP of distal femoral fractures was associated with acceptable rates of complications and generally good functional outcomes. More high-quality, directly comparable research is necessary to validate the conclusions of this review.

Dual plating for fixation failure of the distal femur: Finite element analysis and a clinical series

BACKGROUND

The optimal technique for managing distal femur fixation failure remains inconclusive. The author studied the efficacy of a combined proximal humerus locking compression plate (LCP-PH) and 3.5 mm reconstruction plate (LCP-RP) by finite element (FE) analysis and retrospectively described the clinical outcomes of the present technique in such difficult circumstances.

METHODS

Biomechanical study setting included FE models of the distal femur with remaining holes from previous distal femur LCP (LCP-DF) fixation stabilized with three different constructs i.e., LCP-DF alone, LCP-DF-and-LCP-RP, as well as LCP-PH-and-LCP-RP. All settings were analyzed by using FE under physiological loads. Regarding the clinical series, the outcomes of 8 LCP-DF fixation failures operated on by the present technique were retrospectively reviewed.

RESULTS

High Implant stress of 911.2 MPa and elastic strain at fracture site of 200.8 µɛ were found when stabilized with LCP-DF. The constructs of LCP-DF-and-LCP-RP, and LCP-PH-and-LCP-RP presented lower implant stress compared to LCP-DF, 511.5, and 617.5 MPa, respectively. The elastic strain of both dual plating constructs was also 4-5 times lower than LCP-DF and differed from each other by approximately 10 µɛ. Regarding the clinical series, bony consolidation was achieved in all cases with a mean duration of 28.5 weeks (range 24-36). An average ROM of the affected knee was 115° (range 105-140). Regarding the KSS, 1 was determined to be excellent and 7 to be good.

CONCLUSION

By the biomechanical analysis and the clinical results, the construct of LCP-PH-and-LCP-RP could be an effective technique for revision surgery of LCP-DF fixation failure.

Biomechanical and anatomical considerations for dual plating of distal femur fractures: a systematic literature review

INTRODUCTION

Distal femur fractures are challenging injuries historically associated with high rates of nonunion and varus collapse with operative management. As a result, clinical and research interest in dual plating (DP) of distal femur fractures has seen a dramatic increase in recent years. The purpose of this study was to systematically review the literature regarding vascular anatomy and biomechanics of distal femur fractures treated with DP constructs.

MATERIALS AND METHODS

A systematic literature review of two medical databases (PubMed & Scopus) was performed to identify peer-reviewed studies on the anatomy and biomechanics regarding DP of distal femur fractures. A total of 1,001 papers were evaluated and 14 papers met inclusion criteria (6 anatomy and 8 biomechanics). Methodological quality scores were used to assess quality and potential bias in the included studies.

RESULTS

In the biomechanical studies, DP constructs demonstrated greater axial and rotational stiffness, as well as less displacement and fewer incidences of failure compared to all other constructs. Vascular studies showed that the femoral artery crosses the mid-shaft femur approximately 16.0-18.8 cm proximal to the adductor tubercle and it is located on average 16.6-31.1 mm from the femoral shaft at this location, suggesting that medial plate application can be achieved safely in the distal femur. The methodological quality of the included studies was good for biomechanical studies (Traa score 79.1; range 53-92.5) and excellent for anatomical studies (QUACs score 81.9; range 69.0-88.5).

CONCLUSIONS

Existing biomechanics literature suggests that DP constructs are mechanically stronger than other constructs commonly used in the treatment of distal femur fractures. Furthermore, medial distal femoral anatomy allows for safe application of DP constructs, even in a minimally invasive fashion. Dual plating should be considered for patients with distal femur fractures that have risk factors for instability, varus collapse, or nonunion.

Fixation of Extra-articular Proximal Tibia Fractures: Biomechanical Comparison of Single and Dual Implant Constructs

OBJECTIVES

This biomechanical study seeks to define the relative effectiveness of contemporary single and dual implant constructs for fixation of an extra-articular proximal tibia fracture model.

METHODS

An extra-articular proximal tibia fracture model was created using synthetic tibias. Four constructs were tested. Constructs included (1) lateral locked plate (LLP), (2) intramedullary nail (IMN), (3) combined LLP and IMN (PN), and (4) LLP and medial locked plate. Specimens were axially loaded through the medial plateau to evaluate construct stiffness and the ability to resist varus collapse.

RESULTS

Dual implant constructs were stiffer than single implant constructs in this model. Although DP and PN were stiffer than IMN at all loads tested, the difference was notable only for DP at higher loads. Isolated LLP provided insufficient stability to be tested at higher loads.

CONCLUSION

Dual plate fixation provides the greatest resistance to varus collapse. In the clinical setting, consideration must be given to the fracture morphology, desired construct stiffness, and soft-tissue envelope in selecting the optimal construct to be used.

Double fixation for complex distal femoral fractures

For complex distal femoral fractures, a single lateral locking compression plate or retrograde intramedullary nail may not achieve a stable environment for fracture healing.

Various types of double fixation constructs have been featured in the current literature. Double-plate construct and nail-and-plate construct are two common double fixation constructs for distal femoral fractures.

Double fixation constructs have been featured in studies on comminuted distal femoral fractures, distal femoral fracture with medial bone defects, periprosthetic fractures, and distal femoral non-union.

A number of case series reported a generally high union rate and satisfactory functional outcomes for double fixation of distal femoral fractures.

In this review, we present the state of the art of double fixation constructs for distal femoral fractures with a focus on double-plate and plate-and-nail constructs.

Nail diameter significantly impacts stability in combined plate-nail constructs used for fixation of supracondylar distal femur fractures

Objectives:

Plate-nail (PN) combinations have been described for fixation of supracondylar distal femur fractures. Small diameter retrograde intramedullary nails (rIMN) are commonly used. The purpose of this study was to investigate the effect of nail diameter on construct stability. We hypothesized that a larger diameter rIMN would not significantly change the stiffness of the PN construct when tested in torsional or axial loading.

Methods:

Twelve synthetic osteoporotic femurs were used to compare nail diameters in an extraarticular supracondylar distal femur fracture model (Orthopaedic Trauma Association/Arbeitsgemeinschaft für Osteosynthesefragen type 33-A3). Constructs were fixed with a 12-hole 4.5 mm pre-contoured lateral distal femoral locking plate combined with either a 9 mm (n = 6) or an 11 mm (n = 6) retrograde intramedullary nail (rIMN). Specimens were cyclically loaded in torsion and axial compression. The primary outcome was construct stiffness, calculated using the average slope of the force-displacement curves.

Results:

The 11 mm PN construct was approximately 1.6 times stiffer than the 9 mm PN construct averaged across all torsional loads (2.39 +/− 0.41 Nm/deg vs 1.44 +/− 0.17 Nm/deg) and approximately 1.3 times stiffer than the 9 mm PN construct averaged across all axial loads (506.84 +/− 44.50 N/mm vs 376.77 +/− 37.65 N/mm). There were no construct failures.

Conclusions:

In this biomechanical model, nail diameter had a significant effect on both torsional and axial stiffness in PN constructs. While the use of smaller diameter rIMNs has been proposed to allow for easier placement of implants, the effect on overall construct stiffness should be considered in the context of the patient, their fracture and desired postoperative weight bearing recommendations.

Level of Evidence: N/A

Boundary Conditions Matter - Impact of Test Setup On Inferred Construct Mechanics in Plated Distal Femur Osteotomies

The mechanics of distal femur fracture fixation has been widely studied in bench tests that employ a variety of approaches for holding and constraining femurs to apply loads. No standard test methods have been adopted for these tests and the impact of test setup on inferred construct mechanics has not been reported. Accordingly, the purpose of this study was to use finite element models to compare the mechanical performance of a supracondylar osteotomy with lateral plating under conditions that replicate several common bench test methods. A literature review was used to define a parameterized virtual model of a plated distal femur osteotomy in axial compression loading with four boundary condition sets ranging from minimally to highly constrained. Axial stiffness, longitudinal motion, and shear motion at the fracture line were recorded for a range of applied loads and bridge spans. The results showed that construct mechanical performance was highly sensitive to boundary conditions imposed by the mechanical test fixtures. Increasing the degrees of constraint, for example by potting and rigidly clamping one or more ends of the specimen, caused up to a 25x increase in axial stiffness of the construct. Shear motion and longitudinal motion at the fracture line, which is an important driver of interfragmentary strain, was also largely influenced by the constraint test setup. These results suggest that caution should be used when comparing reported results between bench tests that use different fixtures and that standardization of testing methods is needed in this field.

Dual-Plating in Distal Femur Fracture: A Systematic Review and Limited Meta-analysis

INTRODUCTION

Although lateral locking plate has shown promising results in distal femur fracture, there are high rates of varus collapse and implant failure in comminuted metaphyseal and articular fractures. This systematic review evaluates the functional outcomes and complications of dual plating in the distal femur fracture.

MATERIALS AND METHODS

Manual and electronic search of databases (PubMed, Medline Embase and Cochrane Central Register of Controlled Trials) was performed to retrieve studies on dual plate fixation in the distal femur fracture. Of the retrieved 925 articles, 12 were included after screening.

RESULTS

There were one randomized-controlled, four prospective and seven retrospective studies. A total of 287 patients with 292 knees were evaluated (dual plating 213, single plating 76, lost to follow-up 3). The nonunion and delayed union rates following dual plate fixations were up to 12.5% and 33.3%, respectively. The mean healing time ranged from 11 weeks to 18 months. Good to excellent outcome was observed in 55-75% patients. There was no difference between the single plate and dual plate fixation with regards to the functional outcomes (VAS score, Neer Score and Kolmert's standard) and complications. Pooled analysis of the studies revealed a longer surgical duration (MD - 16.84, 95% CI - 25.34, - 8.35, p = 0.0001) and faster healing (MD 5.43, 95% CI 2.60, 8.26, p = 0.0002) in the double plate fixation group, but there was no difference in nonunion rate (9.2% vs. 0%, OR 4.95, p = 0.13) and blood loss (MD - 9.86, 95% CI - 44.97, 25.26, p = 0.58).

CONCLUSION

Dual plating leads to a satisfactory union in the comminuted metaphyseal and articular fractures of the distal femur. There is no difference between the single plate and dual plate with regards to nonunion rate, blood loss, functional outcomes and complications. However, dual fixation leads to faster fracture healing at the cost of a longer surgical duration.

Biomechanical Analysis and Design Method for Patient-Specific Reconstructive Implants for Large Bone Defects of the Distal Lateral Femur

This study aims to develop a generalizable method for designing a patient-specific reconstructive scaffold implant for a large distal lateral femur defect using finite element (FE) analysis and topology optimization. A 3D solid-core implant for the distal femur defect was designed to withhold the femur load. Data from FE analysis of the solid implant were use for topology optimization to obtain a 'bone scaffold implant' with light-weight internal cavity and surface lattice features to allow for filling with bone material. The bone scaffold implant weighed 69.6% less than the original solid-core implant. The results of FE simulation show that the bone repaired with the bone scaffold implant had lower total displacement (12%), bone plate von Mises stress (34%), bone maximum first principal stress (33%), and bone maximum first principal strain (32%) than did bone repaired with bone cement. The trend in experimental strain with increasing load on the composite femur was greater with bone cement than with the bone scaffold implant. This study presents a generalizable method for designing a patient-specific reconstructive scaffold implant for the distal lateral femur defect that has sufficient strength and space for filling with allograft bone.

[Current status and progress of locking plate in the treatment of distal femoral comminuted fracture]

OBJECTIVE

To review the current status and progress of locking plate for the treatment of distal femoral comminuted fractures.

METHODS

The related literature was extensively reviewed to summarize the current status and progress in the treatment of distal femoral comminuted fracture with locking plate from four aspects: the current treatment situation, the shortcomings of locking plate and countermeasures, the progress of locking technology, locking plate and digital orthopedic technology.

RESULTS

Treatment of distal femoral comminuted fractures is challenging. Locking plates, the most commonly used fixation for distal femoral comminuted fractures, still face a high rate of treatment failure. Double plates can improve the mechanical stability of comminuted fractures, but specific quantitative criteria are still lacking for when to choose double plates for fixation. The far cortial locking screw has shown good application value in improving the micro-movement and promoting the growth of callus. The biphasic plating is a development of the traditional locking plate, but needs further clinical examination. As an auxiliary means, digital orthopedic technology shows a good application prospect.

CONCLUSION

The inherent defect of locking plate is a factor that affects the prognosis of distal femoral comminuted fracture. The optimization of locking technology combined with digital orthopedic technology is expected to reduce the failure rate of treatment of distal femoral comminuted fracture.

Architecture of the cancellous bone in human proximal tibia based on P45 sectional plastinated specimens

PURPOSE

To reveal differences in the pattern of trabecular architecture in the epiphysis and metaphysis of the proximal tibia.

METHODS

The trabecular architecture of the proximal tibia was observed in 27 P45 plastinated knee specimens.

RESULTS

In the medial and lateral condyles, under the articular cartilage surrounded by the medial or lateral meniscus, the cancellous bone is formed by thick and dense trabecular bands, which run longitudinally in the epiphysis and then pass through the epiphyseal line to terminate on the slanted cortex of the metaphysis. In the intercondylar eminence, the trabeculae are arranged basically in a network. In the central portion of the tibial metaphysis, cancellous bone consists of fine arcuate trabeculae, which extend to the anterior and posterior cortices, respectively. These trabeculae are intersected sparsely and form trusses over the medullary cavity. Near the areas of attachment of the iliotibial tract, tibial collateral ligament, anterior and posterior cruciate ligaments, and patellar ligament, the cancellous bone is locally reinforced with patchy trabeculae, dense radiating trabeculae, or two orthotropic trabecular bands.

CONCLUSION

This study provides further accurate anatomical information on the trabeculae of the proximal tibia. The soft structures of knee joint, including the articular cartilage, menisci, and ligaments, and the slanted cortices of the metaphysis are important landmarks for the location of different arrangements of the cancellous architecture. The present results are beneficial for clinical diagnosis and treatment of pathologies of the knee joint, or the establishment of a finite element analysis model of the knee joint.

Supplemental medial small fragment fixation adds stability to distal femur fixation: A biomechanical study

INTRODUCTION

Bridge plating of distal femur fractures with lateral locking plates is susceptible to varus collapse, fixation failure, and nonunion. While medial and lateral dual plating has been described in clinical series, the biomechanical effects of dual plating of distal femur fractures have yet to be clearly defined. The purpose of this study was to compare dual plating to lateral locked bridge plating alone in a cadaveric distal femur gap osteotomy model.

MATERIALS AND METHODS

Gap osteotomies were created in eight matched pairs of cadaveric female distal femurs (average age: 64 yrs (standard deviation ± 4.4 yrs); age range: 57-68 yrs;) to simulate comminuted extraarticular distal femur fractures (AO/OTA 33A). Eight femurs underwent fixation with lateral locked plates alone and were matched with eight femurs treated with dual plating: lateral locked plates with supplemental medial small fragment non-locking fixation. Mechanical testing was performed on an ElectroPuls E10000 materials testing system using a 10 kN/100 Nm biaxial load cell. Specimens were subject to 25,000 cycles of cyclic loading from 100-1000 N at 2 Hz.

RESULTS

Two (2/8) specimens in the lateral only group failed catastrophically prior to completion of testing. All dual plated specimens survived the testing regimen. Dual plated specimens demonstrated significantly less coronal plane displacement (median 0.2 degrees, interquartile range [IQR], 0.0-0.5 degrees) compared to 2.0 degrees (IQR 1.9-3.3, p = 0.02) in the lateral plate only group. Dual plated specimens demonstrated greater bending stiffness compared to the lateral plated group (median 29.0 kN/degree, IQR 1.5-68.2 kN/degree vs median 0.50 kN/degree, IQR 0.23-2.28 kN/degree, p = 0.03).

CONCLUSION

Contemporary fixation methods with a distal femur fractures are susceptible to mechanical failure and nonunion with lateral plates alone. Dual plate fixation in a cadaveric model of distal femur fractures underwent significantly less displacement under simulated weight bearing conditions and demonstrated greater stiffness than lateral plating alone. Given the significant clinical failure rates of lateral bridge plating in distal femur fractures, supplemental fixation should be considered, and dual plating of distal femurs augments mechanical stability in a clinically relevant magnitude.

Nail plate combination in the upper extremity: surgical technique and clinical application

Nail plate constructs (NPC) have shown promising results in complex lower extremity peri-articular fractures as well as in peri-prosthetic fractures. The combination of both implants allows for improved mechanical stability and immediate weight bearing. The use of NPC has not been described in the upper extremity in the literature. We herein describe potential indications and surgical technique for NPC usage for complex upper extremity trauma and reconstruction.

Technical Trick: Dual Plate Fixation of Periprosthetic Distal Femur Fractures

Treatment of periprosthetic distal femur fractures remains challenging due to assuring adequate distal fixation. Traditional treatment options include lateral locked plating and retrograde nailing, although recently dual implant constructs have been explored with promising results. Allowing immediate weight-bearing in this patient population has benefits with regards to rehabilitation and outcome. Recent literature has focused on nail-plate constructs, however plate-plate constructs are preferred at our institution as they do not require arthroplasty component compatibility, facilitate the coronal plane reduction, and allow for immediate weight-bearing.

Augmentation plating leaving the nail in situ is an excellent option for treating femoral shaft nonunion after IM nailing: a multicentre study

PURPOSE

In recent years, plate augmentation over a retained intramedullary (IM) nail has been shown to be an effective option for managing femur fracture nonunions because it improves the biomechanical environment of the fracture site without causing additional biological damage. In the current study, we present outcome data from 22 consecutive patients treated with plate augmentation for femoral shaft nonunion leaving the nail in situ.

PATIENTS AND METHODS

Between 2015 and 2018, 22 consecutive patients with femoral shaft aseptic nonunion after IM nailing were treated with plate augmentation over a retained nail at four different institutions. Nonunion was categorized based on its anatomical location and was classified according to the Weber and Cech classification. Cortical defects greater than 1.0 cm, the type of nailing procedure, and the number of previous interventions were recorded. Patients were assessed clinically and radiographically to measure the healing of nonunion sites. The time to fracture union and complications were recorded. Descriptive statistics were used when applicable.

RESULTS

One site location was supra-isthmic, 12 were isthmic, and 9 were infra-isthmic. There were 10 cases of vascular nonunion and 12 cases of avascular nonunion. A cortical defect greater than 1.0 cm was observed in three patients. Antegrade nailing was performed in 11 patients, and retrograde nailing was performed in 11 patients. Reaming was performed in 12 patients. In eight patients, the fracture was openly reduced during the IM nailing index procedure. The average number of previous interventions before augmentation plating was 1.6 (1-4). Bone union was achieved in 19 patients after augmentation plating with an average follow-up of 23.5 months (12-51 months). Excellent and good clinical results were observed in all patients. There was no plate or screw breakage, and no patient developed infection.

CONCLUSION

Augmentation plating leaving the nail in situ is an excellent option for treating femoral shaft nonunion after IM nailing, with a high union rate and few complications. We believe the technique should gradually replace exchange nailing as the standard of care for the majority of femoral shaft nonunions that occur after IM nailing.