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Femoral neck fracture line structure. The blue line ZO is the axis of the femoral shaft; the pink line is the fracture line of the femoral neck, and the angle of complement of this angle (20°) is the angle of the femoral neck fracture
Source publication
Background
Current surgical interventions for the femoral neck fracture are using either cannulated screws (CCS) or a single large screw at a fixed angle with a side-plate (i.e., a sliding hip screw, AKA dynamic hip screw, DHS). Despite these interventions, the need for reoperation remains high (10.0–48.8%) and largely unchanged over the past 30 ye...
Contexts in source publication
Context 1
... unstable fracture [11]. We first created the femoral shaft axis, a cross which a sagittal plane was created. Then, we created a cutting plate that was across the center of the femoral neck at an angle of 20° with respect to the sagittal plane of the shaft axis. The femoral neck was cut by the cutting plane, simulating a Pauwels type III fracture (Fig. ...
Context 2
... rotational angle in SCAP was the smal- lest of the three groups ( Fig. 6 and Fig. 7). We have actually performed finite element analysis (FEA) by using real bones derived from young (33 years) and old patients (84 years), and they both showed consistent results with that by using Sawbone (Additional file 1: Figure S1 and Additional file 2: Figure S2; Additional file 3: Table S1 and Additional file 4: Table S2). ...
Context 4
... unstable fracture [11]. We first created the femoral shaft axis, a cross which a sagittal plane was created. Then, we created a cutting plate that was across the center of the femoral neck at an angle of 20° with respect to the sagittal plane of the shaft axis. The femoral neck was cut by the cutting plane, simulating a Pauwels type III fracture (Fig. ...
Context 5
... rotational angle in SCAP was the smal- lest of the three groups ( Fig. 6 and Fig. 7). We have actually performed finite element analysis (FEA) by using real bones derived from young (33 years) and old patients (84 years), and they both showed consistent results with that by using Sawbone (Additional file 1: Figure S1 and Additional file 2: Figure S2; Additional file 3: Table S1 and Additional file 4: Table S2). ...
Similar publications
Background
Femoral neck fractures are common injuries. Although many studies have compared two-hole dynamic hip screw (DHS) versus multiple cannulated cancellous screw (CCS) fixation for undisplaced intracapsular fractured neck of femurs (NOF), there is no consensus on which surgical technique results in better outcomes. The aim of our study was to...
Introduction/Objective. Angular stability and dinamyc fixation are key factors to successful healing of femoral neck fractures. We evaluate the efficacy of internal fixation of femoral neck fractures with two parallel self-tapping antirotation screws (SAF) compared to standard, three cannulated cancellous screws (CCS) fixation. Methods. One-hundred...
Citations
... Previous research has focused primarily on biomechanical performance comparisons between DHSs and multiple screw fixation systems for femoral neck fractures [9][10][11][12]. In contrast, direct biomechanical comparisons between CMN and DHS fixations have not been performed. ...
... In contrast, direct biomechanical comparisons between CMN and DHS fixations have not been performed. Existing biomechanical analyses have often emphasized walking and stair climbing under physiological loads, which included vertical weight bearing and associated muscle forces, when assessing bone-implant construct deformation and strength under these conditions [10][11][12][13]. However, the impact of torsion during early ambulation has not been adequately examined. ...
... Specifically, the titanium DHS showed a lower EQV and fragment displacement but a slightly greater SED at the proximal cancellous bone than did the stainless-steel DHS, suggesting a preference for titanium. The approach of the present study, in which hip rotation was simulated through torsional load, contrasts with previous biomechanical evaluations that primarily applied vertical force at the femoral head or physiological loads [10][11][12][13]17]. Previous methods were unable to visualize the torsion effect created by hip rotation, a critical aspect for understanding implant performance. ...
Background
Basicervical femoral neck fracture is a rare proximal femur fracture with a high implant failure rate. Biomechanical comparisons between cephalomedullary nails (CMNs) and dynamic hip screws (DHSs) under torsion loading are lacking. This study compared the biomechanical performance of three fixations for basicervical femoral neck fractures under torsion load during early ambulation.
Methods
The biomechanical study models used three fixations: a DHS, a DHS with an anti-rotation screw, and a short CMN. Finite element analysis was used to simulate hip rotation with muscle forces related to leg swing applied to the femur. The equivalent von Mises stress (EQV) on fixation, fragment displacement, and strain energy density at the proximal cancellous bone were monitored for fixation stability.
Results
The EQV of the short CMN construct (304.63 MPa) was comparable to that of the titanium DHS construct (293.39 MPa) and greater than that of the titanium DHS with an anti-rotation screw construct (200.94 MPa). The proximal fragment displacement in the short CMN construct was approximately 0.13 mm, the greatest among the constructs. The risk of screw cutout for the lag screw in short CMNs was 3.1–5.8 times greater than that for DHSs and DHSs with anti-rotation screw constructs.
Conclusions
Titanium DHS combined with an anti-rotation screw provided lower fragment displacement, stress, and strain energy density in the femoral head than the other fixations under torsion load. Basicervical femoral neck fracture treated with CMNs may increase the risk of lag screw cutout.
Graphical abstract
... These were 2460 N force applied to the femoral head, 1700 N force applied by the abductor muscle and 771 N force applied by the iliopsoas muscle [16] (Figure 2a). The coefficients of friction were 0.46 [17] between the fracture surfaces of the femoral neck, 0.23 [18] between the PFN fragments, and 0.3 [19] between the femur bone fragments and PFN. ...
Triangular screw configuration (TSC) fixation is widely used in clinics for femoral neck fractures, and the appropriate positions of TSC fixation have not been fully described in the literature. This study investigated the optimal fixation of femoral neck fractures with TSC fixation under nonstandard Pauwels angles to determine the ideal position. To determine the optimal fracture line angle and cannulated screw positions, the Pauwels angle and Rotation and Translate variables were parametrically defined in the fracture line and cannulated screw positions. Considering the equivalent stresses on the fracture surfaces, the effectiveness values of the Rotation and Translate 1, 2 and 3 variables are weak, whereas the effectiveness value of the Pauwels angle is high. Considering the equivalent stress on the screws and that the variable value of Translates 1, 2 and 3 is 7 mm, it can be seen that the reverse triangulation configuration is better, and the Pauwels angle is approximately 54°. Among the parameters examined in the study, Pauwels angle was found to have the highest level of effectiveness on femoral neck fracture surfaces and screws. The findings in this study provide a solid basis for future research; however, further clinical research is warranted.
... The coefficient of friction was set to 0.46 (Eberle et al., 2010;Zhan et al., 2020;Li et al., 2021). A load of 1,800 N (three times body weight load) is applied to the femoral head which was abducted 10°, tilted backward by 9°to simulate the one-leg standing, which is the maximum load on the hip joint during human walking (Li et al., 2019). A 15 Nm torsion load was applied to the surface of Frontiers in Bioengineering and Biotechnology frontiersin.org ...
... These parameters can effectively assess the biomechanical state with the greatest risk of internal fixation failure, making them sufficient for stability assessment. In addition, the static load was used to evaluate fracture fixation stability, which is also a common method in finite element analysis (Li et al., 2019;Zhan et al., 2020;Huang et al., 2023). ...
... We have added it to the limitations of the study. Third, the selection of CT images of healthy adults for constructing 3D models is currently a common approach for finite element analysis (Li et al., 2019;Zhan et al., 2020;Huang et al., 2023). However, the representativeness of finite element analysis based on CT data was limited because the methods ignored some factors including BMI, obesity, and muscle atrophy that may have influenced the effectiveness and reliability of the results (Chen et al., 2022). ...
Introduction: Currently, cannulated screws (CSs) and dynamic hip screws (DHSs) are widely used for the treatment of femoral neck fractures, but the postoperative complications associated with these internal fixations remain high. In response to this challenge, our team proposes a new approach involving triangular-supported fixation and the development of the proximal femoral bionic nail (PFBN). The primary objective of this study is to investigate the biomechanical differences among CSs, DHSs, and the PFBN in their capacity to stabilize femoral neck fractures.
Methods: A normal proximal femur model was constructed according to the CT data of a normal healthy adult. A femoral neck fracture model was constructed and fixed with CSs, DHSs, and the PFBN to simulate the fracture fixation model. Abaqus 6.14 software was used to compare the biomechanical characters of the three fracture fixation models.
Results: The maximum stresses and displacements of the normal proximal femur were 45.35 MPa and 2.83 mm, respectively. Under axial loading, the PFBN was more effective than DHSs and CSs in improving the stress concentration of the internal fixation and reducing the peak values of von Mises stress, maximum principal stress, and minimum principal stress. The PFBN fixation model exhibits superior overall and fracture section stability in comparison to both the DHS fixation model and the CS fixation model under axial loading. Notably, the maximum stress and peak displacement of the PFBN and bone were lower than those of the DHS and CS fixation models under bending and torsional loading.
Conclusion: The PFBN shows considerable improvement in reducing stress concentration, propagating stress, and enhancing the overall stability in the femoral neck fracture fixation model compared to DHSs and CSs. These enhancements more closely correspond to the tissue structure and biomechanical characteristics of the proximal femur, demonstrating that the PFBN has great potential for therapeutic purposes in treating femoral neck fractures.
... On the fracture surface, we considered a 0.46 friction coefficient [16]. In regions with no threads, the osteosyntheses touched, but with no friction. ...
... The incidence of implant failure for FNF in patients with preserved bone mineral density is at 10% [10]. This could be related to poor stress distribution in the employed implants, since implants with higher strength and better load distribution minimize the chances of failure [16,21]. By observing stress distribution in the XS and XI models, we noticed a homogeneous stress distribution along the main and positioning screws. ...
Femoral neck fractures (FNFs) affect the young adult population and are intimately related to high-energy trauma. Despite innovations in osteosynthesis materials, the rate of complications remains at 10%-59% in Pauwels type III (PIII) fractures. The authors thus propose a fixation model with a novel self-compression screw, comparing it to a sliding hip screw plate associated with a derotation screw in the fixation of a PIII fracture with posterior inferior comminution. The finite element method (FEM) was used in this comparison along with a virtual femur model with structural characteristics similar to those of a healthy young human bone. We formed 4 groups: Group 1 (GC), intact bone; Group 2 (SHS+S), sliding hip screw plate with derotation screw; Group 3 (XS), X-pin + SS (self-compression model with superior positioning screw); Group 4 (XI), X-pin + IS (self-compression model with inferior positioning screw). A 700 N monotonic load was applied to the apex of the femur head towards the ground so that stress was mainly focused on the fracture site and osteosynthesis. Analyses included total displacement and maximum principal stress and were performed for all groups. Fracture displacement, rotation, and von Mises were assessed only in groups that underwent osteosynthesis. Total displacement values in groups with self-compression screws (XS and XI) were closer to those for healthy femurs, with a 38.5% reduction when comparing the XS group with the SHS+S group. Fracture displacement and rotation values presented reductions of over 60% when comparing the XS and XI groups with the SHS+S group. Equivalent Von Mises stress values were similar between XS and XI and presented a reduction of approximately 5.25% when compared with the SHS+S group. Our FEM analyses demonstrated that the self-compression screw model has potential biomechanical advantages over the SHS+S model.
... The contact conditions were set as friction contact, the friction coefficient between bone and bone was 0.46 [17], the friction coefficient between bone-implant interactions was 0.3 [17], and the friction coefficient between implant-implant interactions was 0.2 [18]. ...
... The contact conditions were set as friction contact, the friction coefficient between bone and bone was 0.46 [17], the friction coefficient between bone-implant interactions was 0.3 [17], and the friction coefficient between implant-implant interactions was 0.2 [18]. ...
Purpose
The ideal approach for revision surgery following femoral head salvage treatments for an intertrochanteric fracture is still up for debate. A novel variety of proximal femoral bionic intramedullary nail (PFBN) has been created in clinical practice. We aimed to compare the biomechanical results of the novel implant to conventional intramedullary and extramedullary fixation in the treatment of intertrochanteric fracture following primary internal fixation failure.
Methods
Using finite element analysis, we created a three-dimensional model of the intertrochanteric fracture's helical blade cut-out for this investigation. The PFBN 1 group, the PFBN 2 group, the PFNA group, and the DHS group were our four test groups. For each fracture group, the von Mises stress and displacements of the femur and internal fixation components were measured under 2100 N axial loads.
Results
The values for the femoral displacement in the PFBN1 group, PFBN2 group, PFNA group, and DHS group were 6.802 mm, 6.716 mm, 8.080 mm, and 8.679 mm, respectively. The internal implant displacement values were 6.201 mm, 6.138 mm, 7.396 mm, and 8.075 mm in the PFBN1 group, PFBN2 group, PFNA group, and DHS group, respectively. The maximum von Mises Stress in the femoral was 187.2 MPa, 85.18 MPa, 106.6 MPa, and 386.2 MPa in the PFBN1 groups, PFBN2 groups, PFNA groups, and DHS groups, respectively. In the PFBN1 groups, PFBN2 groups, PFNA groups, and DHS groups, the maximum von Mises Stress in internal fixation was 586.7 MPa, 559.8 MPa, 370.7 MPa, and 928.4.8 MPa, respectively.
Conclusion
Our biomechanical research demonstrates that intramedullary fixation is more stable than extramedullary fixation when salvaging failed internal fixations in intertrochanteric fracture. Compared with PFNA and DHS, PFBN showed better biomechanical stability in the treatment of patients with revised intertrochanteric fractures. In light of this, we advocate PFBN fixation as the method of choice for intertrochanteric fracture revision. This result still has to be confirmed in more clinical research.
... In the plastic zone, it is possible to determine the ultimate stress that causes a material to fracture. Consequently, rigidity and failure load are widely employed characteristics for defining a mechanical implant material (Basso, 2015;Li et al., 2019). Using load-deformation diagrams, it is possible to calculate the mechanical properties and resistance of an implant. ...
... To accomplish this, rotator cuff fibroblasts may be co-cultured to generate a transitional environment for bone and tendon that is capable of regenerating the interfacial area. In another research study (Li et al., 2009), a mineralized graded scaffold was created using gelatincoated PCL electrospun fibers and plasma-treated PLGA fibers ( Figure 6). The choice of calcium phosphate as a coating was made to promote cellular division and proliferation. ...
... To reduce accumulation time linearly from the bottom to the top of the substrate, tenfold focused simulation fluid was applied at a constant rate. The parameter d indicates the distance from the substrate's lower edge (Li et al., 2009). ...
The objective of bioimplant engineering is to develop biologically compatible materials for restoring, preserving, or altering damaged tissues and/or organ functions. The variety of substances used for orthopedic implant applications has been substantially influenced by modern material technology. Therefore, nanomaterials can mimic the surface properties of normal tissues, including surface chemistry, topography, energy, and wettability. Moreover, the new characteristics of nanomaterials promote their application in sustaining the progression of many tissues. The current review establishes a basis for nanotechnology-driven biomaterials by demonstrating the fundamental design problems that influence the success or failure of an orthopedic graft, cell adhesion, proliferation, antimicrobial/antibacterial activity, and differentiation. In this context, extensive research has been conducted on the nano-functionalization of biomaterial surfaces to enhance cell adhesion, differentiation, propagation, and implant population with potent antimicrobial activity. The possible nanomaterials applications (in terms of a functional nanocoating or a nanostructured surface) may resolve a variety of issues (such as bacterial adhesion and corrosion) associated with conventional metallic or non-metallic grafts, primarily for optimizing implant procedures. Future developments in orthopedic biomaterials, such as smart biomaterials, porous structures, and 3D implants, show promise for achieving the necessary characteristics and shape of a stimuli-responsive implant. Ultimately, the major barriers to the commercialization of nanotechnology-derived biomaterials are addressed to help overcome the limitations of current orthopedic biomaterials in terms of critical fundamental factors including cost of therapy, quality, pain relief, and implant life. Despite the recent success of nanotechnology, there are significant hurdles that must be overcome before nanomedicine may be applied to orthopedics. The objective of this review was to provide a thorough examination of recent advancements, their commercialization prospects, as well as the challenges and potential perspectives associated with them. This review aims to assist healthcare providers and researchers in extracting relevant data to develop translational research within the field. In addition, it will assist the readers in comprehending the scope and gaps of nanomedicine’s applicability in the orthopedics field.
... The femoral neck was divided using the cutting plate to simulate the Pauwell III FNF (Fig. 4). Based on the engineering geometry data and clinical fixation programming, the models of CSs (7.3 mm in diameter, 16 mm in thread length, 85 mm in total length) and BNs (7.3 mm in diameter and 85 mm in total length) were generated using Solidworks software (Solidwords Corp., Waltham, MA) [27]. ...
Purpose
Conventional cannulated screws (CS) are the main treatment method for femoral neck fractures (FNF). However, the rate of femoral head necrosis remains high after FNF treatment. The study aimed to compare the biomechanical features of different internal fixation materials for the treatment of Pauwel type III FNF to explore new strategies for clinical management.
Methods
A new material was prepared by applying casting, freeze drying and sintering process. The independently developed calcium magnesium silicate ceramic powder and hydrogel solution were evenly mixed to obtain a high-viscosity bio-ink, and a bioceramic nail (BN) with high mechanical strength and high fracture toughness was successfully prepared. Four internal fixations were developed to establish the Pauwel type III FNF and healed fracture finite element models: A, three CSs; B, three BNs; C, two BNs and one CS; D, one BN and two CSs. Von Mises stress and displacement of the implants and femur were observed.
Results
The measured Mg content in ceramic powder was 2.08 wt%. The spectral data confirmed that the ceramic powder has high crystallinity, which coincides with the wollastonite-2 M (PDF# 27–0088). The maximum von Mises stresses for the four models were concentrated in the lower part of the fracture surface, at 318.42 Mpa, 103.52 MPa, 121.16 MPa, and 144.06 MPa in models A, B, C, and D, respectively. Moreover, the maximum Von-mises stresses of the implants of the four models were concentrated near the fracture end at 243.65 MPa (A) and 58.02 MPa (B), 102.18 MPa (C), and 144.06 MPa (D). The maximum displacements of the four models were 5.36 mm (A), 3.41 mm (B), 3.60 mm (C), and 3.71 mm (D). The displacements of the three models with BNs were similar and smaller than that of the triple CS fracture model. In the fracture healing models with and without three CSs, the greatest stress concentration was scattered among the lowest screw tail, femoral calcar region, and lateral femur shaft. The displacement and stress distributions in both models are generally consistent. The stress distribution and displacement of the three healed femoral models with BNs were essentially identical to the healing models with three CSs. The maximum von Mises stresses were 65.94 MPa (B), 64.61 MPa (C), and 66.99 MPa (D) while the maximum displacements of the three healed femoral models were 2.49 mm (B), 2.56 mm (C), and 2.49 mm (D), respectively.
Conclusions
Bioceramic nails offer greater advantages than conventional canulated screws after femoral neck fractures. However, the combination of bioceramic nails and CSs is more clinically realistic; replacing all internal fixations with bioceramic nails after the healing of femoral neck fractures can solve the problem of sclerosis formation around CSs and improve bone reconstruction by their bioactivity.
... The traditional fixation of 3CS in an inverted triangle configuration has always been controversial in the treatment of unstable FNFs due to poor mechanical stability [35]. Previous studies have shown a high incidence of hip varus deformity and femoral neck shortening after 3CS fixation [23,36,37], increasing the risk of internal fixation failure and revision via arthroplasty [38]. ...
Background
Self-lock compression anti-rotation blade (SCAB) is a novel internal fixation implant for femoral neck fractures (FNF). We conducted this finite element analysis study to evaluate the biomechanical performances of SCAB combined with a cannulated screw for fixation of Pauwels type III FNF.
Methods
Three finite element models of Pauwels type III FNF treated with various internal fixations were established: a: the inverted triangular parallel cannulated screw (3CS) model, b: the biplane double-supported screw fixation (BDSF) model, c: the SCAB combined with a cannulated screw model. Displacement and Von Mises stress of femurs and internal fixations under increasing loads as well as the average stress on fracture surfaces and maximum displacements on the X and Z axis of proximal fracture fragments at maximum load were measured and compared.
Result
The SCAB-based internal fixation exhibited superior biomechanical performances compared with 3CS and BDSF configurations, as the former resulted in lower parameters including displacement of the femur, Von Mises stress of internal fixation, stress on fracture surfaces as well as X and Z axis displacement of fracture fragments.
Conclusion
Internal fixation using SCAB combined with a cannulated screw for Pauwels type III FNFs shows enough stability, with satisfied resistance to varus and shearing forces, which may provide a new option for the treatment of FNFs.
... CS and DHS have advantages in anti-rotation and maintaining stability, but postoperative complications are still high. Based on the available literature, the failure rate of CS is as high as 13% [12]; 5.3% [13] of patients with lateral thigh pain caused by screw withdrawal make the overall secondary operation rate as high as 33% [14]; [16][17][18] have proved the excellent mechanical properties and good treatment results of FNS. The correction guide included in the FNS device is designed to assist us in accurately inserting the guide wire, but in practice, deviations may occur due to human-operated implantation. ...
... Analyzing the experimental data, in the case of simulating human standing on one foot, the VMS peak value of the femur internal fixation shows that the three fixation positions can effectively bear most of the stress of the lower limbs and provide conditions for fracture healing. The stress of internal fixation in the three groups of models is mainly concentrated in the middle part of the screw close to the fracture line, followed by the transition of the plate-sleeve, which is consistent with that reported in the literature by Li et al. [16] and Fan et al. [19]. This also shows that the idea that adding a CS above the FNS internal fixation device in this experiment to resist better the shear force at the fractured end of the femoral neck is correct. ...
Purpose
There is no specific literature on the best implantation position of the Femoral Neck System (FNS) for treating Pauwels type III femoral neck fracture in young adults.
Methods
Use finite-element analysis to compare the mechanical properties of implantation positions: FNS in the central position, FNS in the low position, and FNS in the low position combined with cannulated screw (CS). The CT data of the femur were imported into the mimics20.0 to obtain the three-dimensional model of the femur; imported into geomagic2017 and SolidWorks 2017 for optimizations; models of FNS and CS are built on the basis of the device manuals. Grouping is as follows: FNS group, FNS-LOW group, and FNS-CS group. Assemble and import them into abaques6.14 for load application. The displacement distribution and von Mises Stress value of them were compared.
Results
On femoral stability and stress distribution, the FNS-CS group performs best, followed by the FNS-LOW group, and finally FNS group. The FNS-LOW group has an improvement over the FNS group but not by much.
Conclusion
In operations, when the implantation position of the central guide wire is not at the center of the femoral neck but slightly lower, it is recommended not to adjust the wire repeatedly in pursuit of the center position; for femoral neck fractures that are extremely unstable at the fracture end or require revision, the insertion strategy of FNS in the low position combined with CS can be adopted to obtain better fixation effects.
... At present, the mainstream internal fixation methods in the clinical applications include: cannulated compression screws (CCS) and dynamic hip screw (DHS) ( Figures 1A,B) (Li et al., 2018). However, the current conventional fixation method interferes greatly with the blood supply in the femoral head (Zhao et al., 2017), and shows insufficient shear force for Pauwels type Ⅲ fracture (Li et al., 2019b). The rate of bone non-union after internal fixation is as high as 10%-34%, and the rate of osteonecrosis is as high as 35%-48%. ...
Objective: To select the most appropriate internal fixation method based on the Pauwels angle, in order to provide a new concept for clinical accurate treatment of femoral neck fractures (FNFs).
Methods: FNFs models of Pauwels 30 ° ; 40 ° ; 50 ° ; 60 ° were created respectively. For Pauwels ≤ 50 ° , 1, 2 and 3 Cannulated Compression Screws (CCS) and Porous Tantalum Screws (PTS) were used to fix the fracture for the models. For Pauwels 60 ° , 3CCS and Medial Buttress Plate (MBP) combined with 1, 2 and 3CCS were used to fix the fracture. Based on the results of the finite element (FE) analysis, the biomechanical properties of each model were compared by analyzing and evaluating the following four parameters: maximal stress of the bone (MBS), maximal stress of the implants (MIS), maximal displacement of bone (MBD), interfragmentary motion (IFM).
Results: At Pauwels 30 ° , the larger parameters were found in 1CCS, which was 94.8 MPa (MBS), 307.7 MPa (MIS), 0.86 mm (MBD) and 0.36 mm (IFM). In 2CCS group, the parameters were 86.1 MPa (MBS), 254.4 MPa (MIS), 0.73 mm (MBD) and 0.27 mm (IFM), which were similar to those of PTS. At Pauwels 40 ° ; 50 ° , with the increase of the number of used CCS, accordingly, the parameters decreased. Particularly, the MIS (Pauwels 50 ° ) of 1CCS was 1,195.3 MPa, but the other were less than the yield range of the materials. At Pauwels 60 ° , the MBS of 3CCS group was 128.6 Mpa, which had the risk of failure. In 2CCS + MBP group, the parameters were 124.2 MPa (MBS), 602.5 MPa (MIS), 0.75 mm (MBD) and 0.48 mm (IFM), The model stability was significantly enhanced after adding MBP.
Conclusion: Pauwels type Ⅰ (< 30 ° ) fractures can reduce the number of CCS, and PTS is an appropriate alternative treatment. For Pauwels type Ⅱ fractures ( 30 ° ∼ 50 ° ), the 3CCS fixation method is still recommended. For Pauwels type Ⅲ fractures (> 50 ° ), it is recommended to add MBP to the medial femoral neck and combine with 2CCS to establish a satisfactory fracture healing environment.
