Comparison of early complications between the use of a cannulated screw locking plate and multiple cancellous screws in the treatment of displaced intracapsular hip fractures in young adults: a randomized controlled clinical trial

Bio-mechanical effects of femoral neck system versus cannulated screws on treating young patients with Pauwels type III femoral neck fractures: a finite element analysis

INTRODUCTION

As a novel internal fixation for femoral neck fractures, the femoral neck system has some advantages for young Pauwels type III femoral neck fractures without clear biomechanical effects and mechanisms. Thus, the objection of the study is to realize the biomechanical effects and mechanism of FNS cannulated screws on treating young patients with Pauwels type III femoral neck fractures compared to cannulated screws which are commonly used for femoral neck fractures by finite element analysis.

METHODS

Firstly, the model of young Pauwels type III femoral neck fractures, femoral neck system (FNS), and three cannulated screws (CS) arranged in an inverted triangle were established, and the internal fixations were set up to fix young Pauwels type III femoral neck fractures. Under 2100 N load, the finite element was performed, and the deformation, peak von Mises stress (VMS), and contact at fracture segments were recorded to analyze the biomechanical effects and mechanism of FNS and three-CS fixing young Pauwels type III femoral neck fractures.

RESULTS

Compared to three-CS, the deformation of the whole model, internal fixation, and fracture segments after FNS fixation were lower, and the peak VMS of the whole model and the internal fixation after FNS were higher with lower peak VMS of the distal femur and the fracture segments. With a sticking contact status, the contact pressure at fracture segments after FNS fixation was lower than that of three-CS.

CONCLUSIONS

FNS can provide better mechanical effects for young patients with Pauwels type III femoral neck fractures, which may be the mechanical mechanism of the clinical effects of FNS on femoral neck fracture. Although there is high stress on FNS, it is still an effective and safe internal fixation for young patients with Pauwels type III femoral neck fractures.

In vitro biomechanical analysis of a locking self-compression screw model applied to Pauwels III and comminuted femoral neck fractures

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.

What is the best method of fixation for minimally displaced subcapital neck of femur fractures? A systematic review

BACKGROUND

Femoral neck fractures are a common cause of morbidity and mortality in the community. Minimally displaced subcapital necks of femoral fractures are usually managed with internal fixation, although there is debate as to which method is superior. This systematic review aimed to compare the outcomes of different fixation methods in the management of this common fracture.

METHODS

This systematic review was conducted in accordance with PRISMA statement guidelines. The databases searched were MEDLINE (Ovid), Cochrane Central Register of Controlled Trials, and EMBASE (Ovid). The study quality and risk of bias were assessed using the Newcastle-Ottawa Quality Assessment Scale, and relevant data were extracted and synthesised.

RESULTS

Nine articles met the inclusion criteria. A total of 819 patients were included in this study. Eight of the nine studies were case series, and one was a randomised control trial. The mean risk of bias was 7.4/9 for non-randomised articles. The fixation methods used in the included studies were dynamic hip screw (DHS), cannulated screws, Smith-Peterson nail, hooknail, Moore's pins, and Knowle's pins. DHS was found to be a superior method of fixation and was supported by a clinical trial. It has high rates of union (99 %), low rates of avascular necrosis (<1 %), and low rates of fixation failure (<1 %).

CONCLUSIONS

Based on the available data, DHS appears to be the superior method of fixation for the minimally displaced subcapital neck of femoral fractures. Given the general low level of evidence currently available, additional clinical trials are needed in this area.

A biomechanical comparison of three fixation methods for unstable femoral neck fractures with medial calcar defect

BACKGROUND

Unstable femoral neck fractures with medial calcar defects are difficult to manage. The optimal fixation methods for these fractures have been a subject of ongoing debate among orthopedic surgeons. In this study, three different fixation techniques for vertical, medial defected femoral neck fractures were compared.

METHODS

In this study, a biomechanical analysis was conducted to compare three fixation methods: cannulated screws (Group 1), cannulated screws combined with a medial buttress plate (Group 2), and intramedullary nails (Group 3). Synthetic composite bone models representing vertical collum femoris fractures with medial calcar defects were used. Each group consisted of seven specimens, and, to maintain consistency, a single surgeon performed the surgical procedure. Biomechanical testing involved subjecting the specimens to axial loading until failure, and the load to failure, stiffness, and displacement values were recorded. Normality was tested using the Shapiro-Wilk test. One-way ANOVA and Tukey's HSD post hoc test were used for comparisons.

RESULTS

The difference in the load to failure values was statistically significant among the groups, with Group 2 exhibiting the highest load to failure value, followed by Group 3 and Group 1. Stiffness values were significantly higher in Group 2 than in the other groups. Displacement values were not significantly different between the groups. Fracture and displacement patterns at the point of failure varied across the groups.

CONCLUSION

The results of this study indicate that fixation with a medial buttress plate in combination with cannulated screws provides additional biomechanical stability for vertical femoral neck fractures with medial calcar defects. Intramedullary nail fixation also demonstrated durable stability in these fractures. These findings can be used to better understand current management strategies for these challenging fractures to promote the identification of better evidence-based recommendations.

Finite element comparative analysis of three different internal fixation methods in the treatment of Pauwels type III femoral neck fractures

BACKGROUND

Comparison of 4 cannulated lag screws (3 inverted triangular cannulated screws + anti-rotating screws;4 CLS), dynamic hip screws + derotational screws (DHS + DS), and femoral neck fixation system (FNS) in the treatment of Biomechanical properties of middle-aged Pauwels type III femoral neck fractures.

METHODS

The femur CT data of a healthy young volunteer was selected and imported into Mimics software to construct a three-dimensional model of a normal femur. Pauwels type III femoral neck fractures were simulated according to the 70° fracture line. Use Geomagic and SolidWorks software to optimize and build CLS, DHS + DS, and FNS fracture internal fixation models. Finally, Ansys software was used to analyze the stress distribution, peak value, and maximum displacement of the proximal fracture fragment and internal fixation; the displacement distribution, and peak value of the fracture surface at the fracture end.

RESULTS

① The stress peaks of the proximal fracture fragments in the three groups were concentrated near the femoral calcar. The peak stress of the FNS group was the largest, and the DHS + DS group was the smallest. ②The displacement of the fracture fragments was all located at the top of the femur. The peak displacement of the FNS group was the largest, and the DHS + DS group was the smallest. ③ The internal fixation stress of the three groups is concentrated in the middle part of the device. The stress distribution of the first two groups of models is more uniform than that of FNS. The peak stress of FNS is the largest and the CLS is the smallest. ④ The internal fixed displacements are all located at the top of the model. The peak displacement of the CLS is the largest, and the DHS + DS is the smallest. ⑤ The displacement of the fracture surface is in the upper part of the fractured end. The peak displacement of the FNS group was the largest, and the DHS + DS group was the smallest.

CONCLUSION

Compared with the other two internal fixation methods, dynamic hip screw + derotational screw (DHS + DS) showed good biomechanical stability. When Pauwels type III femoral neck fracture occurs in young adults, DHS + DS can be given priority as the preferred treatment for this type of fracture.

The role of the medial buttress plate in the treatment of Pauwels type II and III femoral neck fracture in nonelderly patients: a retrospective study and preliminary results

Background

The purpose of this study was to compare the effectiveness of multiple cannulated screws combined with medial buttress plate or not for the treatment of unstable femoral neck fracture in nonelderly patients.

Methods

Sixty-nine nonelderly patients with Garden type III-IV femoral neck fracture were retrospectively analyzed. The patients were divided into MCS (multiple cannulated screws) group and CMBP (combined with medial buttress plate) group according to the surgical method. Patient’s demographic data, Harris Hip Score, EQ-5D index and complications at a minimum of 2 years follow-up were analyzed.

Results

There were 47 patients in the MCS group (35 male and 12 females) with a mean age of 40.28 ± 12.64 years, whereas 22 patients in the CMBP group (17 male and 5 females) with a mean age of 43.86 ± 12.55 years. In the MCS group, there were 1 (2.1%) avascular necrosis, 5 (10.6%) postoperative nonunion, 5 (10.6%) implant failure, and 2 (4.3%) femoral neck shortening. While 1 (4.5%) implant failure, 2 (9.1%) postoperative nonunion and 2 (9.1%) impingement in the CMBP group. For patients with Pauwels type II and III femoral neck fracture, the CMBP group had higher HHS scores at 3 months after surgery than the MCS group (P < 0.05), whereas there was no statistical significance at 6 months, 1 year, and 2 years (P > 0.05). The same results were found in the EQ-5D index.

Conclusions

In our cohort, we observed better outcomes in the CMBP group at 3 and 6 months, with later results similar between groups. However, there were fewer complications in the CMBP group, without obviously blood-supply disruption, especially in Pauwels type II and III. Further, anatomic reduction and stable fixation may contribute to satisfactory outcomes in the treatment of nonelderly displaced femoral neck fractures.

Comparison of the clinical efficacy of a femoral neck system versus cannulated screws in the treatment of femoral neck fracture in young adults

BACKGROUND

To compare the clinical efficacy of a femoral neck system (FNS) and cannulated screws (CS) in the treatment of femoral neck fracture in young adults.

METHODS

Data from 69 young adults, who were admitted for femoral neck fracture between March 2018 and June 2020, were retrospectively analyzed. Patients were divided into two groups according to surgical method: FNS and CS. The number of intraoperative fluoroscopies, operative duration, length of hospital stay, fracture healing time, Harris score of hip function, excellent and good rate of hip function, and postoperative complications (infection, cut out the internal fixation, nail withdrawal, and femoral neck shortening) were compared between the two groups. Hip joint function was evaluated using the Harris Hip Scoring system.

RESULTS

All 69 patients had satisfactory reduction and were followed up for 12-24 months, with a mean follow-up of 16.91 ± 3.01 months. Mean time to fracture healing was13.82 ± 1.59 and 14.03 ± 1.78 weeks in the FNS and CS groups, respectively. There was a statistical difference in the number of intraoperative fluoroscopies between the 2 groups (P = 0.000). There were no significant differences, in operation duration, hospital length of stay, fracture healing time, complications, Harris Hip Score for hip function and excellent and good rate between the two groups (P > 0.05). The incidence of complications was 6.1%(2/33) in the FNS group lower than 25%(9/36) in the CS group, a difference that was statistically significant (P = 0.032). At the last follow-up, the Harris Hip Score of the hip joint in the FNS group was 90.42 ± 4.82and 88.44 ± 5.91 in the CS group.

CONCLUSIONS

Both treatment methods resulted in higher rates of fracture healing and excellent hip function. Compared with CS, the FNS reduced the number of intraoperative fluoroscopies, radiation exposure to medical staff and patients, and short-term complications including femoral neck shortening and bone nonunion.

How to choose the suitable FNS specification in young patients with femoral neck fracture: A finite element analysis

BACKGROUND

Consensus regarding the optimal approach for the treatment of femoral neck fractures remains lacking. A new internal fixation femoral neck system (FNS) was developed and used in clinical practice. We aimed to investigate the biomechanical outcomes of different types of FNS in the treatment of unstable femoral neck fractures.

METHOD

In this study, we constructed three different types of unstable femoral neck fractures of Pauwels classification with angles of 50°, 60°, and 70°. We set up four test groups, namely, the one-hole plated FNS group, two-hole plated FNS group, inverted cannulated screw group and triangle cannulated screw group. Under 2100 N axial loads, displacements and the von Mises stress of the femur and internal fixation components were measured for each fracture group.

RESULTS

When the Pauwels angle was 50°or 60°, the one-hole locking plated FNS was as superior as the two-hole plated FNS in terms of femur and internal fixation displacement, and the inverted cannulated screw had slightly better stability than the triangular cannulated screw. However, when the angle increases to 70°, the two-hole locking plate has the minimum displacement, followed by the triangular cannulated screw and inverted cannulated screw, which is the worst displacement for the single-hole locking plate. Regardless of the angle, the two sets of FNS have higher internal fixation stress than the two sets of cannulated screws, which is approximately 1.6-3.0 times that of the cannulated screw group.

CONCLUSION

From the perspective of biomechanics, we suggest that when the angle of the fracture line is less than 60°, both single-hole locking plated or double-hole locking plated FNS can be used to treat unstable femoral neck fractures. However, when the angle of the fracture line is greater than 70°, we recommend using a double-hole locking plated FNS. This result needs further verification in further clinical studies.

Assessing outcomes in hip fracture patients under the age of 60

BACKGROUND

Hip fractures are a common and serious orthopaedic injury. The principle of treatment for hip fractures in the "non-elderly" patient is to preserve the native hip. There is limited published literature in this area.

AIM

The aim of this research is to review all of the "non-elderly" hip fracture patients to report on the demographics, fracture patterns, fixation types, and revisions.

METHODS

This was a retrospective single-site review of all of the "non-elderly" patients who underwent operative management for hip fractures between 1999 and 2019. A manual review was done of all of the x-rays for the identified patients to confirm the fracture type and identify further surgeries.

RESULTS

Three hundred and eighty-one patients were identified. The average age was 48.4 years old. Two hundred and thirty nine of them were intra-capsular, and 142 of them were extra-capsular fractures. Dynamic hip screw (DHS) was the most popular fixation method. In the recent decade of data, the number of hemi-arthroplasties remained consistent, but the number of total hip arthroplasties (THAs) performed increased sevenfold. Mean follow-up was 35 months. Forty-three (11%) patients required follow-up surgery. Non-union accounted for 56% of all revisions and avascular necrosis for 19%. THA was performed in 70% of all revisions.

CONCLUSION

DHS remains the most widely used fixation technique in an effort to preserve the native hip. The use of THA has increased and surpassed the usage of hemi-arthroplasty in recent times. A high proportion of these patients will go on to develop complications requiring secondary surgery; therefore, they all need long-term follow-up.

Comparison of short-term outcomes between SuperPATH approach and conventional approaches in hip replacement: a systematic review and meta-analysis of randomized controlled trials

Background

It remains uncertain if the new SuperPATH approach benefits patients in artificial hip joint replacement. We conducted a systematic review and meta-analysis of randomized controlled trials to compare the short-term outcome of SuperPATH approach and conventional approaches in hip joint replacement.

Methods

A systematic literature search up to April 2020 was performed to identify randomized controlled trials comparing SuperPATH with conventional approaches in hip joint replacement. We measured surgical, functional, and radiological outcomes. Mean differences or odds ratios with 95% confidence intervals were calculated and pooled using random effects models and the Hartung-Knapp-Sidik-Jonkman method.

Results

A total of 12 RCTs involving 726 patients met the inclusion criteria, one trial with a level I evidence, 11 trials with level II evidence. The overall meta-analysis showed that SuperPATH approach reduced incision length (MD = − 4.84, 95% CI − 7.04 to − 2.64, p < 0.01), pain VAS 7 day postoperatively (MD = − 1.39, 95% CI − 2.57 to − 0.21, p = 0.03), and HHS 7 day postoperatively (MD = 10.24, 95% CI 0.27 to 20.21, p = 0.05). The two approaches did not differ in acetabular cup positioning angles, intra- and postoperative blood loss, hospitalization period, and postoperative complications. Hip replacement via SuperPATH approach had a longer operation time than hip replacement via conventional approaches.

Conclusions

SuperPATH approach showed better results in decreasing incision length and early pain intensity as well as improvement of short-term functional outcome. Long-term outcomes of SuperPATH approach need to be investigated.

Finite element analysis of a new plate for Pauwels type III femoral neck fractures

Background

Method

Result

Conclusion

Factors that influence the complications and outcomes of femoral neck fractures treated by cannulated screw fixation

To investigate the influence of various factors on the two outcome parameters "procedure - specific complication" (femoral head necrosis, infection, nonunion, femoral neck shortening, screw loosening, implant penetration) and "functional outcome" in patients with displaced and undisplaced femoral neck fracture treated by cannulated screw fixation. All cases of a femoral neck fracture, operated by cannulated screw fixation, in the period from December 2014 to December 2017 were included. The observation period of the included patients was 12 months. Information on their outcome was collected after evaluation of current x-ray images and on request from the responsible further treatment physician. Continuous data were presented as mean value ± standard deviation, categorical data as absolute and relative frequency. The effect of potential factors on endpoints was estimated with a multivariable logistic regression analysis and 95% confidence intervals calculated. The null hypothesis Odds Ratio = 1 was checked by the Wald test. The likelihood ratio test was used to test for deviation from linearity. The mean age of the 56 included patients was 72 years (36 min, 96 max), 44.5% (n = 25) were male and 55.5% (n = 25) female. The femoral neck fractures were classified as follows: Garden I: 73%, Garden II: 16%, Garden III: 11%, Pauwels I: 73%, Pauwels II: 21%, Pauwels III: 5%, 31-B1: 73%, 31-B2: 27%, 31-B3: 0%. The factor patient age showed a statistically significant influence on the outcome parameter procedure-specific complication. None of the remaining factors examined showed a statistically significant influence on both outcome parameters procedure-specific complication and functional outcome. 69% of the patients from age 80 onwards suffered a procedure-specific complication. A rate of 41% procedure-specific complications as an outcome parameter in trauma surgery shows a necessity for improvement. The increasing risk of procedure-specific complications for patients with a femoral neck fracture treated by cannulated screw fixation is associated with rising patient age. A more stable head-perserving operative method or an endoprosthetic procedure should be considered in high-risk patients (≥80 y.o.).

Minimally invasive open reduction combined with proximal femoral hollow locking plate in the treatment of Pauwels type III femoral neck fracture

Objective

This study was performed to investigate the clinical effects of minimally invasive open reduction and internal fixation with a proximal femoral hollow locking plate on Pauwels type III femoral neck fractures.

Methods

The clinical data of 45 patients aged 32.0 ± 8.1 years (range, 19–45 years) with Pauwels type III femoral neck fractures treated from March 2012 to August 2016 were retrospectively analyzed. All patients underwent anterolateral minimally invasive open reduction and proximal femoral hollow locking plate fixation of the hip joint. Garden’s index was used to evaluate the quality of fracture reduction. Complications and fracture healing were recorded in all patients. At the last follow-up, the functional outcome was recorded using the Harris hip score.

Results

No complications such as femoral neck shortening, internal fixation loosening, or refracture occurred. However, three patients required reoperation (one with nonunion and two with femoral head necrosis). At the last follow-up, the mean Harris hip score was 92.1 ± 4.5 (range, 76–98). The rate of excellent and good Harris hip scores was 93.3%.

Conclusion

The herein-described strategy for Pauwels type III femoral neck fractures is advantageous in terms of high reduction quality, firm fixation, and prevention of neck shortening.