Extra-articular Distal Femur Fractures Research Articles

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.

To Study the Functional and Radiological Results of Intramedullary Nail with Augmentation Plating in Distal Femur Fractures

This prospective study was conducted on all the patients with extra articular distal femur fractures coming to casualty of Sawai Man Singh Medical College and Hospital Jaipu

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

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. 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. 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. 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.

A comparative study of functional outcome of extra articular distal femur fractures treated, with retrograde nailing versus locking compression plate

Aim: To compare the functional outcome of supracondylar fractures of distal femur managed by Supracondylar nailing (retrograde) and locking femoral compression plate. Introduction: Before 1980, supracondylar fractures of the femur were treated with nonlocking plates. Plaster immobilization and traction were modes of treatment for non-operative patients. Nowadays, the knowledge of internal fixation has evolved as to treat complex fractures by cancellous screws, 95-degree blade plates, dynamic condylar screw and plate, condylar buttress plates, locking femoral compression plates and supracondylar nailing (retrograde). Trending procedures for supracondylar fractures of the femur are supracondylar nail (retrograde) and locking femoral compression plate. Materials and Methods: Totally 30 patients of extra-articular distal femur fractures treated in Rajah Mathai Medical College from May 2019 to June 2021. Patients were treated by random allocation as 15 patients by retrograde nailing and the other 15 patients by distal femur locking compression plate. Functional outcome was compared between them according to Neer’s Scoring System at 24 weeks. Results: In our study, the patients were screened up to 1 year. The assessment was based on both radiologically and clinical scoring. Neer's score was higher in nailing (54%) compared to plating (46%). Conclusion: From our study, nailing proved to have a good functional outcome in terms of early weight-bearing, knee flexion and less union time. Both nailing and plating have excellent results with proper preoperative planning.

Evaluation of cross pinning for stabilization of distal third femoral fractures in dogs

The present study included six dogs with different age, breed, body weight and etiological factors with distal third extraarticular femoral fractures, which were stabilized using K wires by cross pinning method. Postoperatively, the limbs were externally supported by Robert Jones bandage. Complete weight bearing on the operated limb while standing and walking was seen by 10th postoperative day in majority of the dogs. The 60th postoperative day radiographs revealed complete fracture healing with no evidence of fracture line along with cortical and medullary continuity and signs of remodeling. Cross pinning provided effective stabilization in distal metaphyseal and other extra-articular distal femur fractures with more than one point of fixation, leading to early fracture healing.

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.

Supplemental Fixation of Supracondylar Distal Femur Fractures: A Biomechanical Comparison of Dual-Plate and Plate-Nail Constructs

This biomechanical study compares the effectiveness of dual-plate (DP) and plate-nail (PN) constructs for fixation of supracondylar distal femur fractures in synthetic and cadaveric specimens. Twenty-four synthetic osteoporotic femurs were used to compare 4 constructs in an extra-articular, supracondylar fracture gap model (OTA/AO type 33-A3). Constructs included: (1) distal lateral femoral locking plate (DLFLP), (2) retrograde intramedullary nail (rIMN), (3) DLFLP + medial locking compression plate (DP construct), and (4) DLFLP + rIMN (PN construct). DP and PN constructs were then directly compared using 7 matched pairs of cadaveric femurs. Specimens underwent cyclic loading in torsion and compression. Biomechanical effectiveness was measured by quantifying the load-dependent stiffness of each construct. In synthetic osteoporotic femurs, the DP construct had the greatest torsional stiffness (1.76 ± 0.33 Nm/deg) followed by the rIMN (1.67 ± 0.14 Nm/deg), PN construct (1.44 ± 0.17 Nm/deg), and DLFLP (0.68 ± 0.10 Nm/deg) (P < 0.01). The DP construct also had the greatest axial stiffness (507.9 ± 83.1 N/mm) followed by the PN construct (371.4 ± 41.9 N/mm), DLFLP (255.0 ± 45.3 N/mm), and rIMN (109.2 ± 47.6 N/mm) (P < 0.05). In cadaveric specimens, the DP construct was nearly twice as stiff as the PN construct in torsion (8.41 ± 0.58 Nm/deg vs. 4.24 ± 0.41 Nm/deg, P < 0.001), and over one-and-a-half times stiffer in compression (2148.1 ± 820.4 vs. 1387.7 ± 467.9 N/mm, P = 0.02). DP constructs provided stiffer fixation than PN constructs in this biomechanical study of extra-articular distal femur fractures. In the clinical setting, fracture morphology, desired healing mode, surgical approach, and implant cost should be considered when implementing these fixation strategies.

Is Immediate Weight-Bearing Safe After Single Implant Fixation of Elderly Distal Femur Fractures?

To compare early complications in elderly patients with extra-articular distal femur fractures (DFFs) allowed to weight-bear as tolerated (WBAT) immediately versus patients prescribed initial touchdown weight-bearing (TDWB). Retrospective cohort study. Level 1 academic trauma center. One hundred thirty-five patients 60 years or older who underwent surgical fixation of an extra-articular DFF, including the OTA/AO fracture classification of 33-A1-3, and periprosthetic fractures with a stable knee prosthesis (Lewis and Rorabeck type I or II) with at least 6 months follow-up. Immediate WBAT or TDWB after surgical fixation of an extra-articular DFF with either an intramedullary nail or locked plate. The primary outcome was a major adverse event within the first 6 months, defined as (1) early fixation failure or change in alignment leading to reoperation, (2) nonunion, or (3) deep infection. Secondary outcomes included postoperative inpatient length of stay, discharge disposition (secondary facility vs. home), malunion, mortality, and patient-reported outcomes. The rate of early adverse events requiring reoperation was similar between the WBAT group (6, 10.7%) and the TDWB group (15, 19.0%; P = 0.23). There was no difference between groups with respect to length of stay, discharge disposition, malunion, and patient-reported outcomes. This study supports allowing carefully selected elderly patients, based on surgeon preference, to immediately weight-bear after operative fixation of an extra-articular DFF regardless of implant choice. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A study on surgical management of extra articular distal femur fractures by retrograde intramedullary interlocking nail in adults

The distal femur fractures are complex injuries, and it can be challenging to manage. These fractures often are unstable, comminuted and tend to occur in elderly or multiply injured patients. Because of the proximity of these fractures to the knee joint, regaining full knee motion and function may be difficult. 1 If the fracture of the hip square measure excluded, 31% of femoral fractures involve the distal portion. Distal femur fractures by definition require distal 9 cm of the femur [2]. Extra-articular fractures of the distal femur are serious injuries that frequently result in varying degrees of permanent disability. The degree of functional loss is often the result of articular cartilage and bone damage, softtissue injury or a combination thereof [3].Several published studies in the 1960s reported better results with non- surgical than surgical management of distal femur fractures [10, 11]. But now, the most predictable results are presently attained with surgical interventions, and it is now recognized that operative fixation with ability to obtain an anatomical reduction of the joint surface, restoring axial alignment and beginning early range of motion present clear advantage over closed means of treatment [12-16] In 1970, the AO (Arbeitsgemeinschaft fur Osteosynthesefragen) reported

Distal femoral locked plating versus retrograde nailing for extra articular distal femur fractures: A comparative study

Background: Distal femoral fractures are among challenging orthopaedic injuries. Precontoured locked plating and retrograde nailing are two trending methods of fracture fixation in such patients. Purpose of present study was to compare precontoured distal femur locked plating and retrograde intramedullary nailing for treatment of extra articular type A distal femur fractures.Materials and Methods: A prospective randomized study including 32 patients of extra articular distal femur fracures, was conducted in the department of orthopedic surgery, KGMU Lucknow. Patients were divided in two groups by random allocation. Patients of group I (18 patients) were treated by distal femoral locked plating and group II (14 patients) by retrograde distal femoral nailing using standard technique.Results: The mean age of group I and group II was 48.00±15.65 & 40.43±14.39 years respectively. The female – male ratio for both groups was matched (p=.075). The time of full weight bearing was significantly (p=0.004) less in nailing group. Bone union was seen earlier in group II (DFN) and it came to be statistically significant (p value-0.0006). Knee pain was present in 42.86% of patients in group II and it came out to be statistically significant (p

Digital blinding of radiographs to mask allocation in a randomized control trial

AIMTo demonstrate the effectiveness of a digital radiographic altering technique in concealing treatment allocation to blind outcome assessment of distal femur fracture fixation.METHODSDigital postoperative anteroposterior and lateral radiographs from a sample of 33 randomly-selected patients with extra-articular distal femur fractures treated by surgical fixation at a Level 1 trauma center were included. Using commercially available digital altering software, we devised a technique to blind the radiographs by overlaying black boxes over the implant hardware while preserving an exposed fracture site for assessment of fracture healing. Three fellowship-trained surgeons evaluated a set of blinded radiographs twice and a control set of unblinded radiographs once. Each set of radiographs were reviewed independently and in a randomly-assigned order. The degrees of agreement and disagreement among evaluators in identifying implant type while reviewing both blinded and unblinded radiographs were assessed using the Bang Blinding Index and James Blinding Index. The degree of agreement in fracture union was assessed using kappa statistics.RESULTSThe assessment of blinded radiographs with both the Bang Blinding Index (BBI) and James Blinding Index (JBI) demonstrated a low degree of evaluator success at identifying implant type (Mean BBI, far cortical locking: -0.03, SD: 0.04; Mean BBI, standard screw: 0, SD: 0; JBI: 0.98, SD: 0), suggesting near perfect blinding. The assessment of unblinded radiographs with both blinding indices demonstrated a high degree of evaluator success at identifying implant type (Mean BBI, far cortical locking: 0.89, SD: 0.19; Mean BBI, standard screw: 0.87, SD: 0.04; JBI: 0.26, SD: 0.12), as expected. There was moderate agreement with regard to assessment of fracture union among the evaluators in both the blinded (Kappa: 0.38, 95%CI: 0.25-0.52) and unblinded (Kappa: 0.35, 95%CI: 0.25-0.45) arms of the study. There was no statistically significant difference in fracture union agreement between the blinded and unblinded groups.CONCLUSIONThe digital blinding technique successfully masked the surgeons to the type of implant used for surgical treatment of distal femur fractures but did not interfere with the surgeons’ ability to reliably evaluate radiographic healing at the fracture site.

Extra Articular Supracondylar Femur Fractures Managed with Locked Distal Femoral Plate or Supracondylar Nailing: A Comparative Outcome Study.

Despite recent evolution in the operating techniques and surgical implants, debate continues around the choice of implant for management of distal femur fractures. High rates of complications and union difficulties continues to make them a momentous therapeutic challenge. To compare the outcome of locked compressive plating versus retrograde nailing in the management of extra articular supracondylar femur fractures. In this randomized prospective study, 42 patients with extra-articular distal femur fractures were segregated into two groups based on internal fixation with distal femoral locking plate (n=22) and retrograde nail (n=20). Clinical and radiological parameters were studied and functional evaluation was done at 18 months with KSS score. A significant difference in terms of mean duration of surgery and intraoperative blood loss was discerned in favour of plating group although complication rates were equivalent between the groups. Mean duration until union was 26.5 weeks (SD=12.9; range 12 to 64 weeks) in the locked plating and 22.6 weeks (SD=13.1: range 12 to 60 weeks) in the retrograde nail group. The difference came out to be statistically insignificant. Fractures in nailed patients united earlier but the difference was not statistically significant with similar overall union rates. Functional scores too were comparable between them. We deduce that surgical planning and expertise rather than the choice of implant are more crucial for optimal results. Nailing proved more cumbersome intraoperatively due to escalated operating time and blood loss and successive anterior knee pain necessitating implant removal but this detriment may be offset by an inclination towards earlier union. With Less Invasive Stabilization System (LISS), technical errors are more common and less forgiving and must be overcome with proper preoperative planning and intraoperative attention to detail.

Do Locked Compression Intramedullary Nails Improve the Biomechanical Stability of Distal Femoral Fractures?

A distal femur nail with fixed-angle locking screws intends to combine the advantages of angular stability and intramedullary stabilization in extraarticular distal femur fractures. The goal of this study was to analyze whether the locked compression distal femur nail (LCN) was biomechanically more stable than a conventional standard distal femur nail (CN). Both nails were compared on a series of 10 matched pairs of human femora. After setting a distal femur defect fracture, the intramedullary stabilized femur was axially loaded starting from 100 N, increasing in steps of 100 N after every 200 cycles with a triangular frequency of 1 Hz, until a predefined point of failure was reached. The two types of nails showed no significant difference in terms of maximum tolerated load, maximum number of cycles repeated, or axial deformation of the bone-implant construct. The mean load at failure was 2,954 N for the CN and 2,483 N for the LCN. The mean axial deformation for the conventional (14.8 mm) and locked compression nail (15.3 mm) did not differ significantly. Mode of failure was a bony fracture in all specimens predominantly involving the proximal femur. No significant difference in stability between the two compared implants could be demonstrated. The LCN showed comparable characteristics under cyclic axial loading as the conventional distal femur nail. No migration into the articular space or implant failure was observed.

Minimally-invasive internal fixation of extra-articular distal femur fractures using a locking plate: Tricks of the trade

Fractures of the distal femur are rare and occur in two distinct population categories: young patients after high energy traumas and elderly patients who fall from their full height, and often carry severe co-morbidities making especially difficult to manage theses complex injuries. In elderly patients the potential complications are numerous including infection, non-union and frequent function deterioration. We present a technique of minimally invasive internal fixation of the distal extra-articular femur using a locking plate and present the tricks of the trade to obtain successful reduction and achieve union. The hardware used includes plate fixation with a large fragment locking screw. This minimally invasive surgery combines stability of the internal fixation device with the principles of closed surgery, allowing early mobilization and immediate weight bearing to warrant good functional recovery.