Plating Of Distal Femur Fractures Research Articles

Clinical and Radiographic results of a Retrograde Nail - Washer Combination Versus Lateral Locked Plating for Distal Femur Fractures.

The objective of this study was to report outcomes of the Retrograde Femoral Nail-Advanced with Lateral Attachment Washer (RFNA-LAW) (Synthes; Paoli, PA) compared to laterally locked plates (LLP) when treating AO/OTA type 33 distal femoral fractures. Design: Retrospective chart review. Single, academic, Level-1 Trauma Center. All adult patients who had fixation of an AO/OTA type 33 distal femoral fracture with the RFNA-LAW combination or LLP from 2018-2023 with follow-up to union or a minimum of one year. immediately post-operatively and at final follow-up. The main outcome measure was union. Secondary outcomes included implant failure, infection, and alignment immediately post-operatively and at final follow-up. Patients were followed for a minimum of 1-year or to skeletal healing. Forty-eight patients (19 female) with a mean age of 56 years (range 19-94 years) were in the RFNA-LAW group. Fifty-three patients (29 female) with a mean age of 66 years (24-91 years) were in the LLP group. There were no significant differences when comparing Body Mass Index, diabetes, smoking status, mechanism of injury, or fracture classification between groups (p>0.05). There was no difference in immediate, post-operative alignment (p = 0.49). When comparing aLDFA measurements at final follow-up, there was significantly more malalignment in the LLP group (p = 0.005). There were 8 implant failures (15%) in the LLP group compared to 1 in the RFNA-LAW group (2%) (p = 0.02). There were 14 reoperations (26%) in the LLP group compared to 4 (8%) in the RFNA-LAW group (p = 0.02). The Retrograde Nail Advanced - Lateral Attachment Washer combination demonstrated a high union rate when treating complex fractures of the distal femur. When compared to lateral locked plating, this implant combination demonstrated significantly lower rates of nonunion and reoperation. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Severity of Complications after Locking Plate Osteosynthesis in Distal Femur Fractures.

Background: Locked plating for distal femur fractures is widely recommended and used. We systematically reviewed clinical studies assessing the benefits and harms of fracture fixation with locked plates in AO/OTA Type 32 and 33 femur fractures. Methods: A comprehensive literature search of PubMed, Embase, Cinahl, Web of Science, and the Cochrane Database was performed. The studies included randomized and non-randomized clinical trials, observational studies, and case series involving patients with distal femur fractures. Studies of other fracture patterns, studies conducted on children, pathological fractures, cadaveric studies, animal models, and those with non-clinical study designs were excluded. Results: 53 studies with 1788 patients were found to satisfy the inclusion and exclusion criteria. The most common harms were nonunion (14.8%), malunion (13%), fixation failure (5.3%), infection (3.7%), and symptomatic implant (3.1%). Time to full weight-bearing ranged from 5 to 24 weeks, averaging 12.3 weeks. The average duration of follow-up was 18.18 months, ranging from 0.5 to 108 months. Surgical time ranged between 40 and 540 min, with an average of 141 min. The length of stay in days was 12.7, ranging from 1 to 61. The average plate length was ten holes, ranging from 5 to 20 holes. Conclusion: This review aimed to systematically synthesize the available evidence on the risk associated with locked plating osteosynthesis in distal femur fractures. Nonunion is the most common harm and is the primary cause of reoperation. The overall combined risk of a major and critical complication (i.e., requiring reoperation) is approximately 20%.

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

This study described a deformity induced by medial plating of supracondylar distal femur fractures using plates that are precontoured for other anatomic locations. 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. 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 (27.39mm SD 4.78, p = 0.007), shorter medial length (13.57mm SD 4.99, p = 0.028), greater lateral translation (28.82mm 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). 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. IV.

ASSESMENT OF FUNCTIONAL OUTCOME OF DUAL PLATING FOR COMMINUTED DISTAL FEMUR FRACTURE

Background-Distal femur fractures are commonlyassociated with severemetaphysealcomminution and significant soft tissue injury.Locking plating is one of the best and modern options for treating supracondylar femur fractures with relatively low failure rates. Single lateral plating of distal femur fractures was often found to have a relatively higher failure. A medial platingin addition to lateral plating reduces the chances of failure of fixation and prevents varus collapse.The purpose of this study is toAssessment of Functional Outcome of Dual Plating For Comminuted Distal Femur Fracture. Materials and Methods-Following ethical approval, thirty patients with distal femur fractures were treated with dual plating between 1st January 2021 to 31st June 2022.The follow-up studies included clinical and radiographic examinations. All relevant outcomes were recorded during follow-up. Result-All 30 patients were assessed by follow-ups. All follow-up fracture united by the end of study, but delayed union was observed in 5/30 patients. The average union time is 6.2 months (range, 5 to 8 months). The main complication in this study was found to be surgical site infection which occupied 6/30 cases. Conclusion-In our study though there were complications and increase in operating time, the union rate is 100% with no varuscollapse or malunion and functional range of movements were good in 40% of cases and excellent in 25% cases, so double plating is one of the betteroptionto achieve bony union and better functional outcome in severely comminuted distal femur fractures.

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

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.

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

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. 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. 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. 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.

Distal femur nonunion: Risk factors and validation of RUST scores

Abstract Objectives: (1) The purpose of this study was to investigate immediate postoperative weight-bearing status and other potential risk factors for nonunion after locked plating of distal femur fractures and (2) to compare clinical and radiographic union using the previously validated Radiographic Union Scale for Tibia (RUST) and modified RUST scores. Design: This is a retrospective cohort analysis. Setting: Academic Level-1 trauma center. Patients/Participants: Ninety patients with distal femur fractures (OTA/AO 33-A, including periprosthetic) treated with lateral locked plating over a 10-year period. Intervention: Distal femur fracture fixation with lateral locked plating; surgical intervention to facilitate bone healing in cases of nonunion. Main Outcome Measurements: Nonunion rate, construct rigidity scores, RUST, and modified RUST scores. Results: Seventy-eight of 90 patients (87%) achieved clinical union (13% nonunion rate). Rigidity score was significantly associated with risk of nonunion (P = 0.003). No significant association was detected between nonunion and postoperative weight-bearing status (P = 0.77) or other previously identified risk factors. Patients who achieved fracture union had significantly higher mean (SD) RUST (10.67 [1.37] vs. 6.53 [1.48], P &lt; 0.001) and modified RUST (13.47 [2.20] vs. 6.94 [1.79], P &lt; 0.001) scores than patients who developed nonunion. Sensitivity (Sn) analyses identified a RUST score threshold of 9 for diagnosing clinical union (Sn 93.6% and specificity [Sp] 91.7%) and a modified RUST score threshold of 8 (Sn 93.6%, Sp 91.7%). Conclusions: Immediate postoperative weight-bearing status does not seem to affect nonunion rates. We observed a statistically significant association between rigidity score and nonunion. This study supports the utility of the RUST and modified RUST scores in distal femur metaphyseal fractures. Level of Evidence: Therapeutic Level IV.

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

PurposeThis study compared the biomechanical properties of orthogonal plating with plate-nail and parallel plating constructs for supracondylar distal femur fractures. MethodsA 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. ResultsThere 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%). ConclusionOrthogonal 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.

Double-plating approach in the management of isolated distal femoral fractures

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;: Fractures above 9 cm of the articular surface of distal femur are defined as distal femoral fractures which accounts for an estimated 4%-6% of all femur fractures. Stable fixation can be achieved by dual plating of distal femoral fracture. The indications of a dual- lateral and medial plate medial are comminuted distal femur fractures (AO type C3), medial supra-condylar void and bone loss of more than 3 cm, medial Hoffa fracture, inter-condylar comminuted bicondylar fractures, non-union after failed fixation with single lateral plate, poor bone quality.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods&lt;/strong&gt;: The retrospective research study of 35 cases of distal femoral fractures which were treated with lateral and medial plates in post graduate institute Swasthiyog Pratishthan, Miraj (G. S. Kulkarni Hospital, Miraj). The study period was from September 2020 to May 2022. The average follow-up was 8 months.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results&lt;/strong&gt;: 1 year after operation, knee function was evaluated by Oxford knee score along with Mean EQ-5D-5 L score. Functionally the mean oxford knee score was 41.53±1.69, with a maximum Oxford Knee Score of 48. Mean EQ-5D-5 L score was 83.8 (72-82). Average time to union was 9 months (6-12 months). Four (17.4%) cases needed autologous bone graft. &lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions&lt;/strong&gt;: Double incision dual-plating approach for distal femoral fractures is effective and provides stable construct without reduction loss allowing early rehabilitation. Single lateral plating of distal femur fractures was associated with relatively higher failure rate. Addition of medial plate along with lateral plate reduces chances of fixation failure.&lt;/p&gt;

Early peri-implant fractures after distal femur fracture locked plating?

To report the peri-implant fracture rates after locked plating of distal femur fractures and examine risk factors. Over a 7year period, 89 AO/OTA 33A/C distal femur fractures were identified and reviewed. After excluding treatment with intramedullary nails, age under 50, those with the proximal femur protected, or those without 6months of follow-up, 42 distal femur fractures in 41 patients, mean age 72.3 were studied. All were treated with lateral locked plating of distal femur fractures. The details of the constructs were recorded. Mean follow-up was 562days (18.7months). 3/42 were open injuries, 9/42 were type C, 16/42 were type A, and 17 were periprosthetic above a knee arthroplasty. Two patients were treated with a dynamic plating construct using all far-cortical locking (FCL) screws in the diaphysis. 40 patients were treated with a variety of non-dynamic diaphyseal constructs including locking, non-locking, and four with 1-2 FCL screws distally. There was one asymptomatic nonunion. 2/2 patients in the dynamically plated group experienced a peri-implant fracture versus 1/40 in the non-dynamically plated group (p = 0.001). 3/9 with an all-locked construct versus 0/25 patients with a most proximal non-locking screw experienced a fracture. The overall peri-implant fracture risk was 7.1% (3/42), 3/17 patients with a locking screw most proximal experienced a peri-implant fracture, 3/9 with an all-locking construct, and 2/2 patients with a dynamic construct experienced a fracture. These findings merit additional clinical and biomechanical study.

Does distance from joint line influence complications after distal femur fractures in native and periprosthetic knees?

BackgroundDistal femur fractures are projected to increase in incidence secondary to an aging population and growing utilization of total knee arthroplasty. Surgical management is the standard of care, but optimal treatment for far distal fractures is still unclear. Our study investigates if there are distal femur fractures too distal to be treated with lateral locked plating in periprosthetic fractures. MethodsOne hundred and ten consecutive patients treated with locked plating for distal femur fractures around a total knee replacement were identified using CPT codes. Fractures were classified by length of the distal fracture segment and Su classification. Complications studied were nonunion, malunion, infection, further fracture related surgery, readmission within 90 days, and mortality within 1 year of surgery. Sixty six fractures met inclusion criteria of 180 days of follow-up or sustaining a complication prior to180 days. ResultsThe size of the distal fracture segment and Su classification did not correlate with increased complication rate in periprosthetic distal femur fractures. ConclusionsThere was no difference between complications following lateral locked plating of distal femur fractures based on the size of the distal fracture segment in periprosthetic fractures. Lateral locked plating is an effective treatment modality for these fractures regardless of how distal the fracture extends.

Dynamic Locked Plating of Distal Femur Fractures

Abstract Background Distal femur fractures account for less than 1% of all fractures and 3%– 6% of all femur fractures. Epidemiological studies indicate 2 primary distributions of patients: elderly individuals with low energy mechanisms such as a fall from standing, and younger patients with high-energy mechanisms such as motor vehicle accidents. Fixation of the distal femur fracture with lateral locked plate had a nonunion rate between 0 to 32%. The concept of “Dynamic” Locked Plates, has been proposed to decrease construct stiffness &amp; improve callus formation. Objective A systematic review and meta-analysis of literature to assess the outcomes of dynamic locked plate of distal femora fractures. Data Sources Medline databases (PubMed, Medscape, ScienceDirect. EMF-Portal) and all materials available in the Internet till 2018. Data Extraction If the studies did not fulfill the inclusion criteria, they were excluded. Study quality assessment included whether ethical approval was gained, eligibility criteria specified, appropriate controls, and adequate information and defined assessment measures. Conclusion Our systematic review and meta-analysis showed different method of distal femur locked plate dynamyzation. DLP of distal femur increased interfragmentery micro motion, decrease construct stiffness and improve healing &amp; union rate of distal femur fractures. Finally it should be noticed that the orthopedic surgeon should be qualified to utilize either techniques &amp; the choice depends on the preoperative planning &amp; method of fixation available which leads to fracture union on time without complications.

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

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. 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. 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 16.0-18.8cm proximal to the adductor tubercle and it is located on average 16.6-31.1mm 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). Existing biomechanics literature suggests that DP constructs are mechanically stronger than other constructscommonly 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 withdistal femur fracturesthat have risk factors for instability, varus collapse, or nonunion.

Impact on periosteal vasculature after dual plating of the distal femur: a cadaveric study.

Objectives:Although dual plating of distal femur fractures has been described for injuries at risk of varus displacement, the vascular insult to the medial distal femur utilizing this technique is unknown. The aim of this study was to evaluate the perfusion of the medial distal femoral periosteal arteries after supplemental medial plating of the distal femur.Methods:Fifteen human fresh-frozen cadaveric femora were thawed and randomized to lateral locked plating alone or with supplemental medial plate fixation. Conventional submuscular medial plating was performed using a 12-hole small fragment plate and multiple cortical screws. The superficial femoral artery was injected with latex dye. Specimens were dissected. The patency of the medial distal femoral periosteal vessels was evaluated.Results:Four vessels were consistently observed traversing the distal medial femur: the transverse and descending (d-MMPA) branches of the medial metaphyseal periosteal artery, and the transverse and longitudinal branches of the descending geniculate artery. The anterior longitudinal arch (ALA) was present in 13 of 15 specimens and was fed by the d-MMPA. The median number of periosteal arteries occluded by the medial plate was 2 (6 out of 8 specimens). The d-MMPA was occluded in 6 of 8 medially plated femurs, resulting in a complete lack of perfusion of the ALA.Conclusions:Submuscular medial plating of the distal femur compressed the d-MMPA in the majority of specimens. This vessel gives rise to the ALA, which lacked perfusion in these specimens. This vascular insult could affect the healing of metaphyseal distal femur fractures treated with dual plating.

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.

Biphasic plating improves the mechanical performance of locked plating for distal femur fractures

Internal fixation by plate osteosynthesis is the gold standard treatment for distal femur fractures. Despite improvements that preserve the biological conditions for bone healing, there are concerns standard locked plating constructs may be overly stiff. Biphasic plating is a novel concept designed to provide suitable fracture motion and increased implant strength to support early full weight-bearing. This study aims to demonstrate that the Biphasic Plate can be incorporated into a pre-contoured distal femur plate while providing adequate flexibility and increased implant strength.The mechanical performance of the Biphasic Plate (BP) was investigated in comparison to a standard locking plate for the distal femur (LCP-DF). Constructs were formed by mounting the implants on a bone substitute. The construct stiffness and strength under axial loading and the magnitude of interfragmentary movement were determined using finite element analysis.The Biphasic Plate exhibited a bi-linear stiffness response; at low loads, the BP construct was 55% more compliant and at high loads 476% stiffer than the LCP-DF. The Biphasic Plate provided more consistent interfragmentary movement over a wider loading range. At partial weight-bearing loads, the Biphasic Plate produced larger interfragmentary movements (0.18 vs. 0.04 mm). However, at loads equivalent to full weight-bearing, the maximum movements were substantially smaller than the LCP-DF construct (1.5 vs. 3.5 mm). The increased flexibility at low loads was provided without sacrificing implant strength with peak stress in the Biphasic Plate 63% lower than the LCP-DF construct.The biphasic plating concept can be successfully incorporated into anatomically contoured distal femur plates while providing adequate flexibility and increasing implant strength.

Evaluation of callus formation in distal femur fractures after carbon fiber composite versus stainless steel plate fixation.

Carbon-fiber-reinforced polyetheretherketone (CFR) composite plates have a more favorable stress modulus than stainless steel (SS) plates that may confer an advantage to bridge plating. The purpose of this study was to compare callus formation after CFR and SS plating of distal femur fractures. A retrospective review identified distal femoral fractures treated with CFR (n = 10) and SS (n = 21) plate fixation. Callus formation was measured using the modified Radiographic Union Score for Tibia (mRUST) at 3- and 6-month follow-up by three orthopedic trauma surgeons. Loss of alignment, implant failure, and revision surgeries were reviewed. At 3months, the mRUST in the CFR and SS groups was 9.0 (range, 6.3-12.3) and 6.9 (range, 4.3-11.7), respectively (p = 0.01). At 6months, the mRUST in the CFR and SS groups was 11.4 (range, 7.7-16.0) and 10.5 (range, 6.0-15.7), respectively (p = 0.3). CFR and SS groups had a loss of fracture alignment in 1 (10%) and 1 (5%) patient, respectively (p = 0.5), and an unplanned revision surgery in 0 (0%) and 3 (15%) patients, respectively (p = 0.2). All three revisions surgeries in the SS group were for nonunion repair. Treatment of distal femur fractures with CFR versus SS plating resulted in greater callus formation at 3months. At 6months, there was no difference in callus formation between groups. A larger series of patients is necessary to determine if the observed early increased callus formation confers a benefit to clinical outcomes. Therapeutic level III.

Radiostereometric Analysis of Stability and Inducible Micromotion After Locked Lateral Plating of Distal Femur Fractures.

To evaluate interfragmentary motion over 1 year after distal femoral fracture fixation using radiostereometric analysis (RSA). The secondary aim was to assess whether RSA data are consistent with diagnoses of nonunion. Prospective cohort study. Level I urban trauma center. Sixteen patients between 22 and 89 years of age with distal femoral fracture (OTA/AO type 33). All fractures were treated with a lateral locking plate, and tantalum markers were inserted into the main proximal and distal fracture fragments. RSA was performed at 2, 6, 12, 18, and 52 weeks postoperatively. Both unloaded and loaded RSA measurements were performed. Unloaded fracture migration over time and inducible micromotion at the fracture site in the coronal plane were determined at each follow-up interval. RSA precision in the coronal plane of interfragmentary motion over time and inducible micromotion were 1.2 and 0.9 mm in the coronal plane, respectively. Two cases required revision surgery for nonunion 1 year postoperatively. For cases of union, unloaded fracture migration stopped being detectable between 12 and 18 weeks, and inducible micromotion was no longer detectable by the 12-week visit. For cases of nonunion, both unloaded migration and inducible micromotion were detected throughout the study period. RSA may be used to reliably assess distal femoral fracture healing. RSA revealed differences in cases of union and nonunion by 3 months and more consistently than traditional x-rays. Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

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

To investigate the biomechanical properties of a lateral locked plate alone or in combination with a supplemental medial plate or an intramedullary nail (IMN). Intra-articular distal femur fractures with metaphyseal comminution (OTA/AO 33-C) were simulated with a standardized model in 28 synthetic femora and divided into 4 groups. Group I was instrumented with a 4.5-mm lateral locked distal femoral plate alone, group II with a lateral locked plate plus a low-profile precontoured 3.5-mm medial distal tibial plate, group III with a lateral locked plate plus a medial 3.5-mm reconstruction plate, and group IV with a lateral locked plate plus a retrograde IMN. Specimens were then axially loaded and cycled to failure or runout. Outcomes of interest were baseline stiffness, survivability, and cycles to failure. Groups III and IV have a significantly higher baseline stiffness (P < 0.001) when compared with groups I and II. Furthermore, groups III and IV had a higher max load to failure (P < 0.01) when compared with groups I and II. The survivability in groups III and IV was 71% and 100%, respectively, while no specimens in group I or II survived maximum loading. There was no significant difference between group III and IV regarding stiffness, survivability, and cycles to failure. When considering fixation for intra-articular distal femur fractures with metaphyseal comminution (OTA/AO 33-C), we found that supplementation of a lateral locked plate with a medial plate or an IMN to be biomechanically superior to lateral locked plating alone regarding stiffness, survivability, and cycles to failure. A low-profile precontoured plate did not add significantly to the construct stiffness in this study.

Additional fixation of medial plate over the unstable lateral locked plating of distal femur fractures: A biomechanical study

IntroductionLateral locked plating is a standard treatment option for distal femur fractures. However, the unstable conditions after lateral locked plating are increasing. The objective of this study was to investigate the biomechanical strength of additional medial plate fixation over the unstable lateral locked plating of distal femur fractures. Materials and methodsA distal femur fracture model (AO/OTA 33-A3) was created with osteotomies in the composite femur. Three study groups consisting of 6 specimens each were created for single-side lateral locked plating with 6 distal locking screws (LP-6), single-side lateral locked plating with 4 distal locking screws (LP-4), and additional medial locked plating on LP-4 construct (DP-4). A compressive axial load (10 mm/min) was applied in the failure test. Mode of failure, load to failure, and ultimate displacement were documented. ResultsAll single-side lateral locked plating (LP-4 and LP-6) showed plate bending at the fracture gap, while none of the DP-4 showed plate bending at the fracture gap. Load to failure of DP-4 (mean 5522 N) was 17.1% greater than that of LP-6 (mean 4713.3 N, p < 0.05) and 29.2% greater than that of LP-4 (mean 4273.2 N, p < 0.05). Ultimate displacement of DP-4 (mean 5.6 mm) was significantly lower than that of LP-6 (mean 8.8 mm, p < 0.05) and LP-4 (mean 9.1 mm, p < 0.05). ConclusionsAdditional fixation of medial plate significantly increased the fracture stability in distal femur fractures fixed with the lateral locked plating. Especially in the clinical situations where sufficient stability cannot be provided at the distal segment, the medial plate may be considered as a useful biomechanical solution to obtain adequate stability for fracture healing.