Treatment of basicervical femoral neck fractures with proximal femoral nail antirotation

Structure-mechanical analysis of various fixation constructs for basicervical fractures of the proximal femur and clinical implications; finite element analysis

OBJECTIVE

This present study was conducted to determine the structural-mechanical stability of various fixation constructs through finite element (FE) analysis following simulation of a basicervical fracture and to introduce the clinical implications.

MATERIALS AND METHODS

We simulated fracture models by using a right synthetic femur (SAWBONES®). We imported the implant models into ANSYS® for placement in an optimal position. Five assembly models were constructed: (1) multiple cancellous screws (MCS), (2) FNS (femoral neck system®), (3) dynamic hip screw (DHS), (4) DHS with anti-rotation 7.0 screw (DHS + screw), and PFNA-II (Proximal Femoral Nail Antirotation-II®). The femur model's distal end was completely fixed and 7° abducted. We set the force vector at a 3° angle laterally and 15° posteriorly from the vertical ground. Analysis was done using Ansys® software with von Mises stress (VMS) in megapascals (MPa) and displacement (mm) RESULTS: The displacements of the proximal femur were 10.25 mm for MCS, 9.66 mm for DHS, 9.44 mm for DHS + screw, 9.86 mm for FNS, and 9.31 mm for PFNA-II. The maximum implant VMS was 148.94 MPa for MCS, 414.66 MPa for DHS, 385.59 MPa for DSH + screw, 464.07 MPa for FNS, and 505.07 MPa for PFNA-II. The maximum VMS at the fracture site was 621.13 MPa for MCS, 464.14 MPa for DHS, 64.51 MPa for DHS + screw, 344.54 MPa for FNS, and 647.49 MPa for PFNA-II. The maximum VMS at the fracture site was in the superior area with the high point around the posterior screw in the MCS, anterosuperior corner in the DHS, the posteroinferior site of the FNS, and posterosuperior site around the entry point in the PFNA-II. In the DHS + screw, the stresses were distributed evenly and disappeared at the maximum VMS fracture site.

CONCLUSION

Based on the fracture site and implant's stress distribution, the model receiving the optimal load was a DHS + screw construct, and the FNS implant could be applied to anatomically reduced fractures without comminution. Considering the high-stress concentration around the entry point, a PFNA-II fixation has a high probability of head-neck fragment rotational instability.

Cephalomedullary Nailing versus Dynamic Hip Screw Fixation in Basicervical Femoral Neck Fracture: A Systematic Review and Meta-Analysis

PURPOSE

Although many studies have reported the use of dynamic hip screws (DHS) and cephalomedullary nailing (CMN) for basicervical femoral neck fracture (BFNF), no clear treatment protocols have been recommended. The present study aimed to compare the surgical outcomes associated with DHS and CMN to determine the appropriate fixation method for BFNF.

MATERIALS AND METHODS

We systematically searched MEDLINE, Embase, and the Cochrane Library for studies published up to January 9, 2021 that compared the treatment outcomes between CMN and DHS in BFNF. The primary outcomes of the present meta-analysis were fracture union time, postoperative cut-out rate, and reoperation rate.

RESULTS

We included seven studies involving 353 cases of BFNF in our review. Of these, 206 patients were treated using CMN, and DHS were utilized in 147 patients. In a pooled analysis, the DHS group required a longer time to achieve fracture union compared to the CMN group [mean difference (MD): -0.41; 95% confidence interval (CI): -0.70, -0.12; p=0.006; I²=0%]. However, the cut-out and reoperation rates exhibited no statistically significant differences between the DHS and CMN groups [cut-out odds ratio (OR): 0.54; 95% CI: 0.10, 2.82; p=0.47; I²=24%, reoperation rate OR: 0.65; 95% CI: 0.15, 2.86; p=0.57; I²=19%, respectively].

CONCLUSION

Stable fixation using DHS and CMN does not show a significant clinical or radiographical difference in BFNF, and the implant can be selected based on the surgeon's preference.

A Comparative Study of Hip Arthroplasty and Closed Reduction Proximal Femur Nail in the Treatment of Elderly Patients with Hip Fractures

Objective

To compare the clinical effect of hip arthroplasty and closed reduction intramedullary nailing of proximal femur in the treatment of elderly hip fracture patients.

Methods

There are 90 elderly hip fracture patients being recruited in the present study. Fifty patients in Group A received closed reduction intramedullary nailing of proximal femur, and 40 patients in Group B received hip arthroplasty. All patients were followed up for 12 months after surgery, clinical outcomes included surgical indicators, visual analog scale (VAS) score, Harris score, quality of life, mental status, and complications.

Results

The surgery time, bleeding volume, infusion volume of patients in Group A are all significantly lower than those in Group B (p < 0.05), while the weight-bearing activity time and first workout time of Group A are all significantly higher than those in Group B (p < 0.05). The VAS score in patients of Group A at 1 week postoperative is significantly lower than that in patients of Group B (p < 0.05). The Harris score in patients of Group A at 3, 6, and 12 months postoperative are all significantly higher than those in patients of Group B (p < 0.05), and the excellent and good rate of hip function recovery at 12 months postoperative in patient of Group A is significantly lower than that in patients of Group B (80% vs. 95%, p < 0.05). Furthermore, The score of SF-36 standardized physical component, SF-36 standardized mental component and Barthel in patients of Group A at 6 months postoperative are significantly lower than those in patients of Group B (p < 0.05), and the score of mini-mental state examination is significantly higher (p < 0.05), while there are not significantly different at 12 months postoperative (p > 0.05). The incidence of postoperative complications in Group A was significantly lower than that in Group B (10% vs. 27.5%, p < 0.05).

Conclusion

Elderly hip fracture patients treated with closed reduction intramedullary nailing of proximal femur has less surgical trauma and lower complication rates, but slower postoperative recovery compared with hip arthroplasty.

Biomechanical comparison of the femoral neck system and the dynamic hip screw in basicervical femoral neck fractures

The purpose of this study was to compare the fixation stability of proximal fragments and the mechanical characteristics in proximal femur models of basicervical femoral neck fracture fixed by the femoral neck system (FNS) versus the dynamic hip screw. The mean axial stiffness was 234 ± 35 N/mm in the FNS group and 253 ± 42 N/mm in the DHS group, showing no significant difference (p = 0.654). Mean values for x-axis rotation, y-axis rotation, and z-axis rotation after cycle load were 2.2 ± 0.5°, 6.5 ± 1.5°, and 2.5 ± 0.6°, respectively, in the FNS group and 2.5 ± 0.7°, 5.8 ± 2.1°, and 2.2 ± 0.9°, respectively, in the DHS group, showing no significant differences (p = 0.324, p = 0.245, and p = 0.312, respectively). The mean values of cranial and axial migration of screws within the femoral head were 1.5 ± 0.3 and 2.1 ± 0.2 mm, respectively, in the FNS group and 1.2 ± 0.3 and 2.4 ± 0.3 mm, respectively, in the DHS group, showing no significant differences (p = 0.425 and p = 0.625, respectively). The average failure load at vertical load was 1342 ± 201 N in the FNS group and 1450 ± 196 N in the DHS group, showing no significant difference (p = 0.452). FNS fixation might provide biomechanical stability comparable to that of DHS for treating displaced basicervical femoral neck fractures in young adults.

Treatment of Coronal Plane Femoral Intertrochanteric Fractures with a Microexternal Fixator Combined with Proximal Femoral Nail Antirotation

OBJECTIVE

To investigate the different efficacy of proximal femoral nail antirotation (PFNA) combined with or without a microexternal fixator in the treatment of coral-plane femoral intertrochanteric fractures.

METHODS

120 patients with intertrochanteric coronal fractures who received treatment in four hospitals from February 2020 to February 2021 were retrospectively included in this study. They were divided into control (PFNA alone, n = 60) and combined treatment group (a microexternal fixator + PFNA, n = 60) according to different surgery methods. All patients were followed up for 6 months. Operative time, amount of intraoperative blood loss, postoperative length of hospital stays, fracture healing time, Harris hip score, modified Barthel index, hip function excellent and good rate, and incidence of complications were compared between the two groups.

RESULTS

There were no significant differences in operative time, amount of intraoperative blood loss, postoperative length of hospital stay, and incidence of complications between the two groups (all P > 0.05). Fracture healing time in the combined treatment group was significantly shorter than that in the control group (P < 0.05). After surgery, Harris hip score and modified Barthel index in each group were significantly increased compared with before surgery (both P < 0.05). The increases in Harris hip score and modified Barthel index in the combined treatment group were significantly greater than those in the control group (both P < 0.05). After surgery, Harris hip function excellent and good rate in the combined treatment group was significantly higher than that in the control group (83.33% > 66.67%, P < 0.05).

CONCLUSION

Compared with PFNA alone, a microexternal fixator combined with PFNA for the treatment of coronal plane femoral intertrochanteric fractures can greatly shorten fracture healing time and improve postoperative hip function and activities of living ability, but it cannot greatly increase operative time, the amount of intraoperative blood loss, or the risk of postoperative complications.

Treatment of Basicervical Femoral Fracture With Retractable Talon Hip Compression Screw

Background

Basicervical femoral fractures (BFFs) are rare and biomechanically unstable. The goal of this study was to evaluate the effectiveness of the Talon™ DistalFix™ (Orthopedic Designs North America, Inc., Tampa, FL, USA) nail for the treatment of BFFs with a novel design.

Methodology

In this retrospective study, 25 patients with BFFs were analyzed between January 2016 and March 2020 at our institute. All patients were treated with the Talon™ DistalFix™ nail. Patients over the age of 60 years with basicervical fractures caused by low-energy trauma were included in this study. For inclusion into the study, the minimum follow-up time had to be longer than six months. The postoperative radiographic bone union, operative time, tip-apex distance (TAD), sliding distance of the lag screw, quality of fracture reduction, and major complications such as cut-out, non-union of the fracture, femoral head collapse, and cut-through were recorded. The Harris Hip Score was used to evaluate hip function at the end of the follow-up period.

Results

The mean follow-up period was 22 months (range, 16-28 months), and the mean age was 77.8 years (range, 61-91 years). The average sliding distance of the lag screw was 5.7 mm (range, 0.2-13.1 mm). The mean TAD of immediate postoperative view was 20.8 mm (range, 18.7-23.7 mm), and the TAD was <25 mm in all cases. Radiographic union was confirmed in most cases, and the average time for radiographic union was 18.8 weeks (range, 12-25 weeks). Most fractures (90.5%) had healed with no postoperative mechanical complications (cut-out, cut-thorough, or lateral wall fracture) at the final follow-up, except for two patients. One of the two patients had no evidence of union at six months, and mild varus reduction was observed in the other patient who had shortening of >10 mm.

Conclusions

According to the clinical and radiological findings of this study, treatment with the Talon™ DistalFix™ nail showed satisfactory results. Hence, it can be a suitable option in the treatment of BFFs.

Outcomes of Ipsilateral Femoral Neck and Shaft Fractures Treated With Proximal Femoral Nail Antirotation 2

Ipsilateral femoral neck and shaft fractures are relatively rare fractures, which most commonly occur in young adults following high-energy trauma. In most cases of such fractures, neck fracture is undisplaced and often of basicervical type. Many treatment methods have been described, but there is still no generalized consensus on the same. Cephalomedullary nails are one of the preferred modalities of treatment. A cephalomedullary nail-like proximal femoral nail antirotation 2 (PFNA 2) of recent design is being widely used currently. In this study, we present 13 cases of ipsilateral femoral neck and shaft fractures treated with PFNA 2 implants. The advantages of the PFNA 2 system include reduced blood loss, reduced operative time, and fewer fluoroscopy shots. PFNA 2 is a biomechanically better implant than many cephalomedullary implants. It provides satisfactory results in ipsilateral femoral neck and shaft fractures, especially where neck fracture is of a basicervical type. Some aspects have to be taken care of when employing PFNA 2, such as anatomical reduction, and length, angulation, and rotation of both neck and shaft.

Epidemiology, classification, treatment, and mortality of adult femoral neck and basicervical fractures: an observational study of 40,049 fractures from the Swedish Fracture Register

BACKGROUND

Although femoral neck fractures (FNFs) are common in orthopedic departments, optimal treatment methods remain in dispute. There are few large nationwide studies, including basicervical FNFs (bFNFs), on epidemiology, treatment, and mortality. This nationwide study aims to describe the epidemiology, fracture classification, current treatment regimens, and mortality of undisplaced and minimally displaced (Garden I-II, uFNF), displaced (Garden III-IV, dFNF) and bFNFs in adults.

METHODS

All FNFs, including bFNFs with a registered injury date between 1 April 2012 and 31 December 2020, were included in this observational study from the Swedish Fracture Register (SFR). Data on age, sex, injury mechanism, fracture classification, primary treatment, and seasonal variation were analyzed.

RESULTS

Some 40,049 FNFs were registered in the SFR. The mean age of the patients in the register was 80.3 (SD 11) years and 63.8% (25,567) were female. Of all FNFs, 25.0% (10,033) were uFNFs, 63.4% (25,383) dFNFs, and 11.6% (4,633) bFNFs. Non-surgical treatment was performed in 0.6% (261) of the patients. Internal fixation (IF) (84.7%) was the main treatment for uFNFs and arthroplasty (87.3%) for dFNFs. For bFNFs, IF (43.8%) and hip arthroplasty (45.9%) were performed equally often. Of the 33,105 patients with a 1-year follow-up mortality at 1-year was 20.6% for uFNF, 24.3% for dFNF, and 25.4% for bFNF.

CONCLUSION

The main treatment of uFNFs is IF with screws or pins. Hip arthroplasty is the predominant treatment for dFNF. bFNF are more common than previously reported and treated with IF or arthroplasty, depending on patient age. These results may help health care providers, researchers and clinicians better understand the panorama of FNFs in Sweden.

LEVEL OF EVIDENCE

IV, retrospective cohort study.

Treatment and outcomes of basicervical femoral neck fractures: A systematic review

PURPOSE

This study aims to systematically review the literature comparing surgical treatments options and respective failure rates for basicervical hip fractures.

METHODS

A comprehensive search of databases, including MEDLINE, Embase, Web of Science, and Cochrane Central for studies published in English on or before June 21, 2019 was performed. Selected search terms included "basicervical," "basi cervical," "AO/OTA type 31-B," "femoral neck fracture" AND "bone nails," "bone screws," "fracture fixation," "internal fixation," "arthroplasty," "cephalomedullary," "sliding hip screw," "ORIF," and "treatment outcome." We included studies that assessed outcomes of basicervical fracture fixation using open reduction internal fixation or arthroplasty. Two authors extracted the following data from each paper: study design, country, cohort year, definition of basicervical, intervention type, sample size, patient demographics, follow-up length, percent of fractures that required revision, and the percent of implants that failed.

RESULTS

Sixteen articles encompassing 910 patients were included. The main outcome was the percent of implants that required revision. The total revision rates were 8% (8 studies, 157 patients, range 0%-55%) for cephalomedullary nails, 7% (10 studies, 584 patients, range 0%-18%) for sliding hip screws, 23% (3 studies, 40 patients, range 16%-50%) for cannulated screws, 0% (1 study, 6 patients) for total hip arthroplasty, and 8% (2 studies, 13 patients, range 0%-11%) for hemiarthroplasty.

CONCLUSION

Management of basicervical fractures with SHS and CMN produces similar failure and re-operation rates. Limited evidence is available on the use of cannulated screws and arthroplasty, but available studies suggest that cannulated screws have an unacceptable revision rate (23%) while arthroplasty may be acceptable. Future studies examining the comparative efficacy of various fixation methods would benefit from strict definition of fracture type as well as consistent reporting of functional outcomes, re-operation rates, and mortality.

Outcomes of basicervical femoral neck fracture treated with percutaneous compression plate (PCCP)

INTRODUCTION

Basicervical femoral neck fracture is associated with high rates of failure due instability patterns, mainly collapse and rotational instability. The purpose of this study was to evaluate the clinical-radiological results of a group of patients with a bascervical proximal femoral fractures treated with Percutaneous Compression Plate (PCCP).

MATERIAL AND METHODS

Among 5817 patients with a hip fracture who were admitted in our hospital from January 2005 to December 2017, 234 factures (4%) were diagnosed of basicervical femoral fracture. 30 of them were treated with a PCCP, 22 women and 8 men, mean age was 81.2 years (63-94). Demographic and perioperative variables were collected. The patients were followed up at 1, 3 and 6 months clinically and radiologically.

RESULTS

There were no intra-operative complications and no conversions to open surgery. There was no early implant failure. No surgical wound infection was diagnosed. Crude mortality was 13% the first year and 87% were able to walk at the 6 months. The last follow-up x-rays revealed 97% fracture healing and the collapse at fracture site occurred in 4 hips. No instances of cut-out were observed. In one case, a fatigue failure of the lag screws of a PCCP plate was observed at 3 months from osteosynthesis.

CONCLUSION

PCCP is an appropriated implant for basicervical femoral neck fractures.

Finite element analysis of fixation effect for femoral neck fracture under different fixation configurations

In this study, the biomechanical differences among three internal fixation configurations for treatment of Pauwels type II and III femoral neck fractures were analyzed. Using finite element analysis, the femur displacement and stress distributions of the internal fixation device and fracture section were obtained for different patients and movement conditions. The results show that patients with osteoporosis are more prone to femoral varus and femoral neck shortening, and the fracture probability of the device for these patients is higher than that for patients with normal bone. The treatment effect of the inverted-triangle screw (ITS) fixation and proximal femoral nail anti-rotation (PFNA) fixation is better than that of dynamic hip screw (DHS) fixation. The ITS fixation is more suitable for the treatment of the normal bone patients with Pauwels II femur neck fracture. However, the PFNA fixation has better biomechanical advantages and better capability for anti-femoral neck shortening. Therefore, it is suitable for the treatment of femoral neck fracture patients with osteoporosis.

Review on Basicervical Femoral Neck Fracture: Definition, Treatments, and Failures

Basicervical femoral neck fracture is an uncommon fracture that accounts for only 1.8% of all proximal femoral fractures. Previous studies have recommended that the choice of implant to treat this fracture should be similar to that of intertrochanteric fracture. However, in previous studies on basicervical fractures, the definition and treatment results of these fractures were different, and there were also debates on the implant that had to be used. Therefore, the purpose of this study was to review the studies that performed surgical treatment of basicervical femoral fractures and to assess the definition of basicervical fracture, the use of implants, and failure rates and clinical results. Study selection was based on the following inclusion criteria: (1) treatment outcome for basicervical femoral neck fracture was reported; and (2) dynamic hip screw, proximal femoral nail, or multiple screw fixation was used as treatment. PubMed Central, OVID MEDLINE, Cochrane Collaboration Library, Web of Science, EMBASE, and AHRQ databases were searched to identify relevant studies published up to March, 2020 with English language restriction. A total of 15 studies were included in this study. Differences were found in the definition of basicervical fracture, treatment results, rehabilitation protocol, and fixation failure rate. Definitions and treatment methods for basicervical fractures varied, and treatment outcomes also differed among the enrolled studies. Further research is needed that would be restricted to those fractures that conform to the definition of basicervical fracture.