Complications following young femoral neck fractures

Screw Configuration Does Not Significantly Alter Neck Shortening After Valgus-Impacted Femoral Neck Fracture (OTA Type 31B1.1)

OBJECTIVES

To compare 3 different cancellous screw configurations used for Garden 1 femoral neck fractures (FNFs).

METHODS

DESIGN

Retrospective review.

SETTING

A large urban academic medical center.

PATIENT SELECTION CRITERIA

All patients with Orthopaedic Trauma Association 31B1.1 FNF who underwent in situ fixation with cancellous screws between 2012 and 2021 were included. Patients were divided into 3 groups: 2 screws placed in a parallel fashion, 3 screws placed in an inverted triangle configuration, and 3-screw fixation with placement of 1 "out-of-plane" screw perpendicular to the long axis of the femur.

OUTCOME MEASURES AND COMPARISONS

Postoperative femoral neck shortening (mm) was the primary outcome, which was compared among the 3 groups of different screw configurations.

RESULTS

Sixty-one patients with a median follow-up of 1 year (interquartile range 0.6-1.8 years) and an average age of 72 years (interquartile range 65.0-83.0 years) were included. All fractures demonstrated bony healing. Overall, 68.9% of the cohort had ≤2 mm of femoral neck shortening. There was no difference between groups in the proportion of patients who experienced greater than 2 mm of shortening (P = 0.839) or in the amount (mm) of femoral neck shortening (Kruskal-Wallis χ2 = 0.517, P = 0.772).

CONCLUSIONS

Although most patients with valgus-impacted FNF treated with screw fixation do not experience further femoral neck shortening, some patients demonstrated continued radiographic shortening during the healing process. The development of further femoral neck shortening and the amount of shortening that occurs do not differ based on implant configuration. Multiple different screw configurations seem to be acceptable for achieving healing and minimizing further femoral neck impaction.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Changing treatment of hip fractures in Finland

INTRODUCTION

Hip fracture treatment should be as standardized and effective as possible, with emphasis on fast recovery and avoidance of complications, especially those leading to reoperations. There is accumulating evidence regarding the optimal treatment of hip fractures but reports of whether this has influenced treatment in the clinical setting are sparse. The objective of this study was to determine the trends of hip fracture incidence and treatment in Finland, with special regard to how we treat older patients compared to younger ones.

MATERIALS AND METHODS

All operatively treated hip fractures in Finland between 1997 and 2018 were identified from a national administrative register. The incidence of these fractures and operations performed to treat them were calculated based on the adult population size.

RESULTS

Apart from a decline in the elderly age groups during the first half of the study period, the incidence of hip fractures remained relatively constant. However, the incidences of different operations changed significantly. In treatment of femoral neck fractures from 1997 to 2018, the incidence of cemented hemiarthroplasty (HA) increased from 41.1 to 59.9 per 100,000 person-years (105) and hybrid total hip arthroplasty (THA) from 0.56 to 5.93 per 105, while the incidence of internal fixation (IF) decreased, for instance screw fixation from 12.5 to 2.7 per 105. The incidence of cementless HA decreased from 13.3 to 1.2 per 105. These changes were much more pronounced in the elderly population and there was a statistically significant difference in the proportion of patients aged > 59 treated with cemented HA and IF in 1997 compared to 2018. For trochanteric and subtrochanteric fractures, treatment with intramedullary nails replaced extramedullary devices as the most common treatment method.

CONCLUSIONS

The changes in treatment methods in Finland correspond to the increasing knowledge available about the optimal treatment of hip fractures and global treatment trends.

Case Series: Bilateral Operative Femoral Neck Stress Fractures in Marine Corps Recruits

Bone stress injuries are well-documented injury patterns among U.S. Armed Forces recruits because of the rapid increase in frequency and intensity of bone-impacting activities throughout training. In the recruit population, femoral neck stress fractures are of great concern because of their propensity to progress, displace, and lead to lifelong complications like avascular necrosis. We present two cases of bilateral operative femoral neck stress fractures. The first is of a 28-year-old male Marine Corps recruit who experienced bilateral groin pain during the first week of training. He was found to have bilateral grade 4 femoral neck stress fractures with concomitant effusions. Operative management was pursued with bilateral percutaneous pinning. For this patient, one hip had classically indicated operative involvement while on the contralateral hip the decision to operate was based on recent literature predicting progression based on the presence of a joint effusion. The second case is of a 23-year-old male Marine Corps recruit who experienced hip pain in the final few weeks of training. He was also found to have bilateral grade 4 femoral neck stress fractures with concomitant effusions and was similarly operated on. To the best of our knowledge, this is the first reported operative bilateral femoral neck stress fracture case series in a military-aged patient in the literature. A high clinical suspicion for femoral neck stress injuries with early diagnostic imaging for high-risk groups was important in these cases and ultimately led to timely definitive management for this patient.

Clinical features of pediatric femoral neck fractures and analysis of risk factors for avascular necrosis of the femoral head: A retrospective case-control study of 45 patients

OBJECTIVES

To summarize the clinical features of pediatric femoral neck fractures and analyze the risk factors for avascular necrosis of the femoral head.

METHODS

A retrospective analysis of the case data of pediatric femoral neck fractures treated in our hospital from January 2010 to December 2022, including gender, age, fracture type, causative factors, and surgical details. The occurrence of avascular necrosis of the femoral head was recorded and risk factors were analyzed.

RESULTS

From January 2010 to December 2022, a total of 45 cases of femoral neck fractures were treated in our hospital with a median age at onset of 93 months (IQR=81) and a median time from injury to surgery of 96 hours (IQR=46). Closed reduction was performed in 36 cases, while open reduction was performed in 9 cases. Avascular necrosis of the femoral head occurred in 29 cases postoperatively, while it did not occur in 16 cases. Increased time from injury to surgery and greater degree of fracture displacement were independent risk factors for avascular necrosis of the femoral head. The risk of avascular necrosis in Garden IV type femoral neck fractures was significantly higher than in Garden II and III type patients. An injury-to-surgery time exceeding 82.5 hours was identified as a critical threshold for the development of avascular necrosis of the femoral head.

CONCLUSION

Pediatric femoral neck fractures have a low incidence rate and are mostly caused by high-energy trauma, often resulting in severe injuries. Therefore, actively maintaining stable vital signs and properly managing associated injuries, timely surgical intervention for femoral neck fractures, achieving good reduction and fixation of displaced fractures are crucial in the treatment of pediatric femoral neck fractures.

Biomechanical evaluation of Gamma 3 nail with anti-rotation screw fixation for unstable femoral neck fractures: a biomechanical study

This study aims to evaluate the biomechanical performance of the Gamma 3 nail with an anti-rotation screw (GNS) and compare it to two established gold-standard methods for treating unstable femoral neck fractures (UFNFs). Synthetic bone models were prepared with Pauwels' type III osteotomy and an additional posterior wedge. Three different implant configurations were tested: three cannulated crews (3CS) in an inverted triangle configuration, a dynamic hip screw with an anti-rotation screw (DHSS), and GNS. Non-destructive cyclic axial loading was applied at 7° adduction, with 1000 cycles ranging from 100 to 1000 N. Subsequently, a construct failure test was conducted using progressive axial compression, and fracture reduction loss was recorded. The average axial stiffness was 321 ± 52 N/mm for 3CS, 430 ± 71 N/mm for DHSS, and 519 ± 104 N/mm for GNS. The average ultimate failure loads were 2699.3 N for 3CS, 3427.1 N for DHSS, and 3758.9 N for GNS. GNS demonstrated significantly greater axial stiffness compared to the other two groups (P < 0.05). Both DHSS and GNS exhibited similar failure loading, which were greater than those of 3CS (P < 0.05). GNS offers the advantages of a minimally invasive and intramedullary implant with comparable stability to the DHSS system. Moreover, GNS demonstrated superior biomechanical performance compared to 3 CS configuration.

Femoral Neck Fractures With Associated Ipsilateral Femoral Shaft Fractures in Young Adults <50 Years Old: A Multicenter Comparison of 80 Cases Versus Isolated Femoral Neck Fractures

OBJECTIVES

To analyze patients, injury patterns, and treatment of femoral neck fractures (FNFs) in young patients with FNFs associated with shaft fractures (assocFNFs) to improve clinical outcomes. The secondary goal was to compare this injury pattern to that of young patients with isolated FNFs (isolFNFs).

METHODS

DESIGN

Retrospective multicenter cohort series.

SETTING

Twenty-six North American level-1 trauma centers.

PATIENT SELECTION CRITERIA

Skeletally mature patients, <50 years old, treated with operative fixation of an FNF with or without an associated femoral shaft fracture.

OUTCOME MEASURES AND COMPARISONS

The main outcome measurement was treatment failure defined as nonunion, malunion, avascular necrosis, or subsequent major revision surgery. Odds ratios for these modes of treatment were also calculated.

RESULTS

Eighty assocFNFs and 412 isolFNFs evaluated in this study were different in terms of patients, injury patterns, and treatment strategy. Patients with assocFNFs were younger (33.3 ± 8.6 vs. 37.5 ± 8.7 years old, P < 0.001), greater in mean body mass index [BMI] (29.7 vs. 26.6, P < 0.001), and more frequently displaced (95% vs. 73%, P < 0.001), "vertically oriented" Pauwels type 3, P < 0.001 (84% vs. 43%) than for isolFNFs, with all P values < 0.001. AssocFNFs were more commonly repaired with an open reduction (74% vs. 46%, P < 0.001) and fixed-angle implants (59% vs. 39%) (P < 0.001). Importantly, treatment failures were less common for assocFNFs compared with isolFNFs (20% vs. 49%, P < 0.001) with lower rates of failed fixation/nonunion and malunion (P < 0.001 and P = 0.002, respectively). Odds of treatment failure [odds ratio (OR) = 0.270, 95% confidence interval (CI), 0.15-0.48, P < 0.001], nonunion (OR = 0.240, 95% CI, 0.10-0.57, P < 0.001), and malunion (OR = 0.920, 95% CI, 0.01-0.68, P = 0.002) were also lower for assocFNFs. Excellent or good reduction was achieved in 84.2% of assocFNFs reductions and 77.1% in isolFNFs (P = 0.052). AssocFNFs treated with fixed-angle devices performed very well, with only 13.0% failing treatment compared with 51.9% in isolFNFs treated with fixed-angle constructs (P = <0.001) and 33.3% in assocFNFs treated with multiple cannulated screws (P = 0.034). This study also identified the so-called "shelf sign," a transverse ≥6-mm medial-caudal segment of the neck fracture (forming an acute angle with the vertical fracture line) in 54% of assocFNFs and only 9% of isolFNFs (P < 0.001). AssocFNFs with a shelf sign failed in only 5 of 41 (12%) cases.

CONCLUSIONS

AssocFNFs in young patients are characterized by different patient factors, injury patterns, and treatments, than for isolFNFs, and have a relatively better prognosis despite the need for confounding treatment for the associated femoral shaft injury. Treatment failures among assocFNFs repaired with a fixed-angle device occurred at a lower rate compared with isolFNFs treated with any construct type and assocFNFs treated with multiple cannulated screws. The radiographic "shelf sign" was found as a positive prognostic sign in more than half of assocFNFs and predicted a high rate of successful treatment.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Investigation of Novel Radiological Parameters to Predict Treatment Failure and Ideal Surgical Interventions in Young Femoral Neck Fractures Treated with Triple Cannulated Screw: A Retrospective Analysis

Introduction

Treatment failure remains a challenge in young femoral neck fractures treated with triple cannulated screws (TCS). This study aims to identify novel radiological parameters that can predict treatment failure and propose surgical techniques to enhance the success of TCS or aid in selecting alternative methods.

Patients and methods

We conducted a retrospective analysis of 87 patients who underwent surgery for femoral neck fractures between February 2014 and June 2022, meeting the inclusion criteria. Patients achieving union were categorized as Non-Fail (Group 1), while those experiencing nonunion were categorized as Fail (Group 2). Various demographic and clinical factors were assessed, including age, gender, fracture side, and fracture classification (Garden and Pauwels). Radiological parameters such as fragmentation in the medial cortex, postoperative fracture displacement in the calcar region, collo-diaphyseal angle (CDA) difference (varus/valgus alignment), and several newly defined parameters (modified tip apex distance (m-TAD), tip cortex distance (TCD), upper-lower screw-cortex distance/neck diameter, the calcar screw-cortex distance/neck diameter (Buyukdogan index), and sub-capital area/basocervical area (Dogan index) were evaluated. Patients developing nonunion were studied to establish potential cut-off values based on radiological parameters.

Results

Of the patients, 61 were classified as Non-Fail (Group 1) and 26 as Fail (Group 2). Both groups exhibited similar distributions in terms of gender, fracture side, Pauwels classification, and follow-up times (p > 0.05). However, Group 2 had a higher mean age than Group 1 (p = 0.006). There was a significant difference between the two groups in terms of Garden classification (p = 0.0003). Furthermore, postoperative calcar displacement, varus alignment, m-TAD, TCD, upper-lower screw-cortex distance/neck diameter ratio, Buyukdogan index, and Dogan index showed significant differences between the groups (p < 0.05). Conversely, medial calcar fragmentation did not differ significantly between the groups (p > 0.05).

Conclusions

The Dogan index (≤ 0.5) can serve as an independent preoperative predictor of treatment failure, aiding in the selection of more effective surgical interventions than TCS. Varus alignment (> 10 degrees), the upper-lower screw-cortex distance to the neck diameter (> 0.45) and Buyukdogan index (> 0.2) are influenced by the surgical technique of TCS application and should be considered to decrease the success of TCS.

Treatment Failure After Repair of Displaced Femoral Neck Fractures in Patients Compared by "Decade of Life": An Analysis of 565 Cases in Adults Less Than 60 years of Age

OBJECTIVES

To study the results of displaced femoral neck fractures (FNFs) in adults less than 60 years of age by comparing patients, injury, treatment, and the characteristics of treatment failure specifically according to patients' age at injury, that is, by their "decade of life" [ie, "under 30" (29 years and younger), "the 30s" (30-39 years), "the 40s" (40-49 years), and "the 50s" (50-59 years)].

METHODS

DESIGN

Multicenter retrospective comparative cohort series.

SETTING

Twenty-six North American Level 1 Trauma Centers.

PATIENT SELECTION CRITERIA

Skeletally mature patients aged 18-59 years with operative repair of displaced FNFs.

OUTCOME MEASURES AND COMPARISONS

Main outcome measures were treatment failures (fixation failure and/or nonunion, osteonecrosis, malunion, and the need for subsequent major reconstructive surgery (arthroplasty or proximal femoral osteotomy). These were compared across decades of adult life through middle age (<30 years, 30-39 years, 40-49 years, and 50-59 years).

RESULTS

Overall, treatment failure was observed in 264 of 565 (47%) of all hips. The mean age was 42.2 years, 35.8% of patients were women, and the mean Pauwels angle was 53.8 degrees. Complications and the need for major secondary surgeries increased with each increasing decade of life assessed: 36% of failure occurred in patients <30 years of age, 40% in their 30s, 48% in their 40s, and 57% in their 50s (P < 0.001). Rates of osteonecrosis increased with decades of life (under 30s and 30s vs. 40s vs. 50s developed osteonecrosis in 10%, 10%, 20%, and 27% of hips, P < 0.001), while fixation failure and/or nonunion only increased by decade of life to a level of trend (P = 0.06). Reparative methods varied widely between decade-long age groups, including reduction type (open vs. closed, P < 0.001), reduction quality (P = 0.030), and construct type (cannulated screws vs. fixed angle devices, P = 0.024), while some variables evaluated did not change with age group.

CONCLUSIONS

Displaced FNFs in young and middle-aged adults are a challenging clinical problem with a high rate of treatment failure. Major complications and the need for complex reconstructive surgery increased greatly by decade of life with the patients in their sixth decade experiencing osteonecrosis at the highest rate seen among patients in the decades studied. Interestingly, treatments provided to patients in their 50s were notably different than those provided to younger patient groups.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Optimal Fixation Strategies for Displaced Femoral Neck Fractures in Patients 18-59 Years of Age: An Analysis of 565 Cases Treated at 26 Level 1 Trauma Centers

OBJECTIVES

The objective of this study was to determine the difference in failure rates of surgical repair for displaced femoral neck fractures in patients younger than 60 years of age according to fixation strategy.

METHODS

DESIGN

This is a retrospective, comparative cohort study.

SETTING

Twenty-six Level 1 North American trauma centers.

PATIENT SELECTION CRITERIA

Patients younger than 60 years of age with a displaced femoral neck fracture (OTA 31-B2, B3) undergoing surgical repair from 2005 to 2017.

OUTCOME MEASURES AND COMPARISONS

Patient demographics, injury characteristics, repair methods used, and treatment failure (nonunion/failed fixation, avascular necrosis, and need for secondary surgery) were compared according to fixation strategy.

RESULTS

Five hundred and sixty-five patients met inclusion criteria and were studied. The mean age was 42 years, 36% were female, and the average Pauwels' angle of fractures was 55 degrees. There were 305 patients treated with multiple cannulated screws (MCS) and 260 treated with a fixed-angle (FA) construct. Treatment failures were 46% overall, but was more likely to occur in MCS constructs versus FA devices (55% vs. 36%, P < 0.001). When FA constructs were substratified, the use of a sliding hip screw with addition of a medial femoral neck buttress plate (FNBP) and "antirotation" (AR) screw demonstrated better results than either FNBP or AR screw alone or neither with the lowest overall construct failure rate of 11% (P < 0.036).

CONCLUSIONS

Historically used fixation constructs for femoral neck fractures (eg, multiple cannulated screws and sliding hip screw) in young and middle-aged adults performed poorly compared with more recently proposed constructs, including those using a medial femoral neck buttress plate and an antirotation screw. Fixed-angle constructs outperformed multiple cannulated screws overall, and augmentation of fixed-angle constructs with a medial femoral neck buttress plate and antirotation screw improved the likelihood of successful treatment. Surgeons should prioritize fixation decisions when repairing displaced femoral neck fractures in patients.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison of three different internal fixation methods in the treatment of femoral neck fracture

Objective

This study aimed to assess the efficacy of three different fixation methods in treating femoral neck fractures in young patients.

Methods

A retrospective analysis was conducted on 35 young patients with femoral neck fractures who underwent surgical treatment. Among them, 16, 12, and 7 patients underwent fixation with three cannulated compression screws (3CS), the femoral neck system (FNS), and the compound compression system (CCS), respectively. Data, including fracture classification, injury-to-surgery time, surgery duration, intraoperative blood loss, fluoroscopy instances, fracture healing time, complications, and Harris score at the final follow-up, were collected and analyzed to compare clinical outcomes among the three fixation methods.

Results

All patients were followed for at least 6 months, exhibiting no significant differences in age, gender, injury side, fracture type, or injury-to-operation time among the three groups (P > 0.05). The FNS and CCS groups exhibited shorter operation durations and fewer intraoperative fluoroscopy instances compared to the 3CS group (P < 0.01). Despite the minimally invasive nature of 3CS, the FNS and CCS groups experienced higher intraoperative blood loss (P < 0.01). During follow-up, only one patient with 3CS fixation developed nonunion. Additionally, patients treated with 3CS demonstrated a higher incidence of femoral head necrosis and severe femoral neck shortening than the FNS and CCS groups. Excluding patients with combined nonunion, no significant difference in mean fracture healing time was observed among the three groups (P > 0.05). At the last follow-up, the FNS and CCS groups showed higher Harris scores (P < 0.05).

Conclusions

Both FNS and CCS are effective internal fixation systems for the treatment of femoral neck fractures in young patients, yielding more satisfactory clinical functional outcomes than 3CS. Comparatively, the CCS system presents a higher risk of iatrogenic rotation of the proximal fracture segment. Therefore, we advocate the insertion of two to three 2.5 mm Kirschner wires from the upper edge of the femoral neck along the axial direction before CCS lag screw insertion to resist iatrogenic rotational stress.

The synthes femoral neck system (FNS): a technical tip and case series

The femoral neck system (FNS) was recently introduced for treatment of femoral neck fractures. A novel feature is an anti-rotation screw with a diverging design from the neck bolt to provide rotational stability. Using the 4 Nm torque limiting screwdriver might cause the incomplete insertion of the screw specifically in dense or sclerotic bone. A nontorque limiting manual screwdriver should be used to complete the insertion and locking of the screw to prevent this error. We present series of seven cases with incomplete insertion of the anti-rotation screw in patient with femoral neck fractures treated with the FNS.

Comparison of dynamic compression system versus multiple cancellous screws in the treatment of femoral neck fractures in young adults

INTRODUCTION

Femoral neck fractures have posed a significant global healthcare challenge and had notable impacts on the quality of life. Current treatment strategies for femoral neck fractures in young individuals have varied, emphasizing the need for optimal fixation methods. This study compared the clinical and radiological outcomes of the dynamic compression system (DCS) and multiple cancellous screws (MCS) methods.

METHODS

This retrospective study included a total of 275 young adults with fresh femoral neck fractures treated with DCS and MCS. A matching analysis with a 1:1 ratio based on age, gender, fracture classification, and reduction quality was conducted. Demographic data were recorded, and comparisons were made according to follow-up time (FUT), hospitalization period, operation duration, femoral neck shortening, caput-collum-diaphysis (CCD) angle, Harris Hip Score (HHS), and post-operative complications.

RESULTS

A total of 42 fractures were matched with a median age of 42 years (range, 22-48). In the DCS group, vertical neck shortening (median 1.92) was significantly lower than that in the MCS group (median 4.53) (P < 0.05). In the DCS group, horizontal femoral neck shortening, resultant femoral neck shortening, the amount of change in CCD angle, and HHS were 0.57 mm (0.43, 4.74 mm), 1.82 mm (0.40, 3.53 mm), 0.13° (-0.78°, 1.80°), and 91 (85-93), respectively. They were all non-significant than 1.00 mm (0.56, 6.23 mm), 2.74 mm (1.59, 6.71 mm), -0.18° (-1.11°,1.85°), and 91 (75, 93) in the MCS group, respectively (P > 0.05). There was no statistical difference in FUT, hospitalization period, operation time, and post-operative complications at the latest follow-up (P > 0.05). There were no complications such as pulmonary embolism, deep vein thrombosis, and incision infection reported.

CONCLUSION

DCS and MCS demonstrated effectiveness in treating femoral neck fractures in young adults. The DCS implant provides additional stability in the vertical axis. A prospective randomized controlled study with a large sample size was needed to validate these findings.

Evaluating three internal fixation techniques for Pauwels III femoral neck fractures via finite element analysis

The selection of implants for fixing unstable femoral neck fractures (FNF) remains contentious. This study employs finite element analysis to examine the biomechanics of treating Pauwels type III femoral neck fractures using cannulated compression screws (3CS), biplane double-supported screw fixation (BDSF), and the femoral neck system (FNS). A three-dimensional model of the proximal femur was developed using computed tomography scans. Fracture models of the femoral neck were created with 3CS, BDSF, and FNS fixations. Von Mises stress on the proximal femur, fracture ends, internal fixators, and model displacements were assessed and compared across the three fixation methods (3CS, BDSF, and FNS) during the heel strike of normal walking. The maximum Von Mises stress in the proximal fragment was significantly higher with 3CS fixation compared to BDSF and FNS fixations (120.45 MPa vs. 82.44 MPa and 84.54 MPa, respectively). Regarding Von Mises stress distribution at the fracture ends, the highest stress in the 3CS group was 57.32 MPa, while BDSF and FNS groups showed 51.39 MPa and 49.23 MPa, respectively. Concerning implant stress, the FNS model exhibited greater Von Mises stress compared to the 3CS and BDSF models (236.67 MPa vs. 134.86 MPa and 140.69 MPa, respectively). Moreover, BDSF displayed slightly lower total displacement than 3CS fixation (7.19 mm vs. 7.66 mm), but slightly higher displacement than FNS (7.19 mm vs. 7.03 mm). This study concludes that BDSF outperforms 3CS fixation in terms of biomechanical efficacy and demonstrates similar performance to the FNS approach. As a result, BDSF stands as a dependable alternative for treating Pauwels type III femoral neck fractures.

Low avascular necrosis rates in femoral neck fractures: efficacy of cannulated screw fixation

PURPOSE

Cannulated screw fixation for femoral neck fractures is often limited by concerns of avascular necrosis (AVN) occurring, historically seen in 5-40% of fixed intracapsular fractures. This study aims to assess the outcomes, particularly the AVN rate, associated with current surgical techniques within our unit.

METHODS

We conducted a single-center cross-sectional study, manually searching operative records between July 14, 2014, and December 1, 2018, identifying patients with intracapsular fractured neck of femur fixed with cannulated screws, with a minimum of two years follow-up. Patient records and radiographs were reviewed for clinical and radiographic diagnoses of AVN, non-union, post-operative metalwork infection, and screw penetration of the head. Additionally, fracture pattern and displacement, screw configuration, reduction techniques, and adequacy of reduction were recorded, with radiographs independently analyzed by four orthopedic surgeons.

RESULTS

Fifty-six patients were included; average age of 67 years (range 30-100). Forty-two patients (75%) sustained displaced fractures and 14 patients (25%) had undisplaced fractures. Two (4%) patients developed AVN, with no cases of non-union, post-operative metalwork infection or screw penetration of the head. Eight patients (14%) sustained a high-energy injury, though none of these patients developed AVN. All fractures required closed reduction; no open reductions performed. Twenty-seven (64%) of reductions were adequate.

CONCLUSION

Our observed AVN rate is notably lower than the widely reported figures, even among a significant proportion of displaced fractures that were fixed. This study underscores that with adequate fixation, cannulated screws represent an excellent option for treating intracapsular neck of femur fractures, even in cases of displaced fracture patterns with imperfect reduction.

Low reoperation rate after fixation of displaced femoral neck fractures with the femoral neck system (FNS)

PURPOSE

Operative fixation of femoral neck fractures (FNFs) remains challenging. Complications are not infrequent, especially in displaced patterns. Numerous fixation techniques have been previously described in the literature; however, there remains a paucity of data regarding outcomes of these injuries treated with the femoral neck system (FNS).

METHODS

Patients with a displaced FNF (OTA/AO 31B) treated with the FNS at a single level 1 academic trauma center between 1/1/2019 and 1/1/2023 were identified. Radiographs were reviewed to assess fracture displacement, location, and characteristics. Patient records were further reviewed to assess for complications, reoperations, and osseous union.

RESULTS

Forty-three patients (65% male) with 44 FNFs were identified with a mean age of 35.0 years (range, 13-61 years). Two patients developed a deep infection requiring surgical debridement, four patients underwent a total hip arthroplasty, and one patient underwent a valgus intertrochanteric osteotomy for nonunion. There were three cases of femoral head AVN. Mean follow-up was 482.5 days among all patients, and 36 fractures had at least 6 months of follow-up or reached bony union.

CONCLUSIONS

Here, we present a series of patients treated with the FNS for internal fixation and report a 18% reoperation rate. This is lower than the average rate that has been previously reported in similar patient populations in the literature treated with alternative methods of internal fixation. Thus, the FNS appears to be a safe and effective option for treatment of these injuries.

MRI characteristics of radiographically occult femoral neck fractures in trauma patients with ipsilateral femoral shaft fractures

PURPOSE

Ipsilateral femoral neck fractures can be seen alongside femoral shaft fractures in high-velocity trauma patients. These neck fractures are often occult on radiographs and CT, and can have a significant impact on patient outcomes if not treated promptly. Limited protocol pelvic MRI has been used to increase sensitivity for these occult fractures. Detailed characterization of these fractures on MRI is lacking.

METHODS

427 consecutive trauma patients presenting to our emergency department who had known femoral diaphyseal fractures but no ipsilateral femoral neck fracture on radiographs or CT were included in this study. These patients were scanned using a limited protocol MRI with coronal T1 and coronal STIR sequences. Presence of an ipsilateral femoral neck fracture and imaging characteristics of the fracture were obtained.

RESULTS

31 radiographically occult ipsilateral femoral neck fractures were found, representing 7% of all cases. All neck fractures were incomplete. All fractures originated along the lateral cortex of the femoral neck and extended medially towards the junction of the medial femoral neck and the lesser trochanter. 58% (18/31) were vertical in orientation. 61% (19/31) did not demonstrate any appreciate edema on STIR images.

CONCLUSION

Implementation of limited protocol MRI protocol increases sensitivity for detection of femoral neck fractures in the setting of ipsilateral femoral shaft fractures not seen on radiograph or CT imaging. We describe the characteristic MR imaging features of these fractures.

Pilot study of three novel implants-GSK triangular system, locking hip screw and controlled sliding dynamic hip screw, for fixation of fracture of the neck of femur

BACKGROUND AND OBJECTIVE

Intra capsular fracture of the neck of femur (FNF) treated traditionally with a dynamic hip screw (DHS) or three cancellous screws (3CS) has a high incidence of complications with reoperation rates between 20 % and 45 %. We hypothesized that FNF unites by primary healing. Therefore, intra-operative compression and absolute stability post-operatively until healing are essential. We postulated that FNF requires 2 types of implants- those which provide absolute stability for young patients with good bone stock and another with sliding mechanism for elderly patients with osteoporosis. We developed three novel fixation systems at our research institute in India using a modified DHS. In patients with good bone stock, locking DHS, called LHS and GSK triangular system (GSKT) provided intra-operative compression and absolute stability during the post-operative period. In those with poor bone stock, the controlled sliding DHS (CSDHS)was used as a locking implant might penetrate the hip joint.

MATERIALS AND METHOD

42 patients of FNF <55 years of age were studied. Among 39 patients with good bone stock, LHS was used in five patients and GSKT system was used in 34 patients. CSDHS was used in three patients with poor bone stock or communition. The patients were followed up for a minimum of eight months up to a maximum of two years, with the average follow up duration of 14 months.

RESULTS

32 out of 34 fractures treated by GSKT system united. Five cases managed by LHS and three by CSDHS, all united. The union rate was 95.2 %. Of the two failed cases, one patient had nonunion (NU), the other had deep infection. Avascular necrosis of the head (AVN) was detected in three patients treated with GSKT system in the second year following surgery. Two of them had hip pain while one was asymptomatic. Eight cases of FNF Pauwels type III underwent a primary valgus osteotomy. All of them united without complications.

CONCLUSION

In patients with good bone stock, LHS and GSKT system allowed intra-operative compression and absolute post-operative stability without sliding of head fragment as the triangle construct is biomechanically the strongest. When bones are osteoporotic, a CSDHS provided controlled sliding (1 to 5 mm only). This pilot study showed a promising success rate of 95.2 %. We propose that the GSKT system may be used to treat intertrochanteric and other metaphyseal fractures as well. Further biomechanical studies are underway to strenghten the evidence needed for the widespread use of these implants.

Comparison of femoral neck shortening after femoral neck system and cannulated cancellous screw fixation for displaced femoral neck fractures in young adults

BACKGROUND

The purpose of this study was to compare the outcomes of femoral neck shortening between the femoral neck system (FNS) and the cannulated cancellous screws (CCS) for displaced femoral neck fractures in young adults PATIENTS AND METHODS: In this retrospective analysis, 225 patients aged 18-65 years with displaced femoral neck fracture were divided into two groups according to internal fixation: 135 patients in the FNS group and 90 patients in the CCS group. The length of hospital stay, duration of surgery, intraoperative blood loss, quality of reduction, extent of femoral neck shortening, incidence of femoral neck shortening, femoral neck shortening at each follow-up visit, Harris hip score (HHS), reoperation, and complications were compared between the two groups.

RESULTS

The median follow-up time was 28.2 (26.0, 31.2) months in the FNS group and 30.2 (26.3, 34.7) months in the CCS group. The follow-up time, age, sex distribution, body mass index (BMI), mechanism of injury, injured side, length of hospital stay, time from injury to surgery, and fracture classification were similar between the groups. Duration of surgery was longer in the FNS group (65.0 (55.0, 87.0) min versus 55.0 (50.0, 65.0) min, P<0.001); intraoperative blood loss was greater in the FNS group (50.0 (20.0, 60.0) ml versus 20.0 (10.0, 35.0) ml, P<0.001). Femoral neck shortening was 2.4 (1.0, 4.5) mm in the FNS group versus 0.6 (0.0, 2.6) mm in the CCS group at 1 month postoperatively (P<0.001); 3.7 (1.8, 6.4) mm in the FNS group versus 1.2 (0.6, 3.8) mm in the CCS group at 3 months (P<0.001); 4.1(2.4, 7.7) mm in the FNS group versus 2.3 (1.1, 4.4) mm in the CCS group at 6 months (P<0.001); 4.2 (2.6, 7.7) mm in the FNS group versus 2.6 (1.3, 4.6) mm in the CCS group at 12 months (P<0.001); and 4.5 (2.8, 8.0) mm in the FNS group versus 2.8 (1.5, 4.8) mm in the CCS group at 18 months (P<0.001). The two groups showed no significant differences in HHS, reoperation, and reduction quality.

CONCLUSION

Compared to CCS, FNS is deficient in preventing femoral neck shortening. Future research should focus on improving FNS in terms of preventing femoral neck shortening.

Residual deformity after femoral neck fracture affects the location of osteonecrosis of the femoral head

Aims

The localization of necrotic areas has been reported to impact the prognosis and treatment strategy for osteonecrosis of the femoral head (ONFH). Anteroposterior localization of the necrotic area after a femoral neck fracture (FNF) has not been properly investigated. We hypothesize that the change of the weight loading direction on the femoral head due to residual posterior tilt caused by malunited FNF may affect the location of ONFH. We investigate the relationship between the posterior tilt angle (PTA) and anteroposterior localization of osteonecrosis using lateral hip radiographs.

Methods

Patients aged younger than 55 years diagnosed with ONFH after FNF were retrospectively reviewed. Overall, 65 hips (38 males and 27 females; mean age 32.6 years (SD 12.2)) met the inclusion criteria. Patients with stage 1 or 4 ONFH, as per the Association Research Circulation Osseous classification, were excluded. The ratios of anterior and posterior viable areas and necrotic areas of the femoral head to the articular surface were calculated by setting the femoral head centre as the reference point. The PTA was measured using Palm's method. The association between the PTA and viable or necrotic areas of the femoral head was assessed using Spearman's rank correlation analysis (median PTA 6.0° (interquartile range 3 to 11.5)).

Results

We identified a negative correlation between PTA and anterior viable areas (rho -0.477; p = 0.001), and no correlation between PTA and necrotic (rho 0.229; p = 0.067) or posterior viable areas (rho 0.204; p = 0.132).

Conclusion

Our results suggest that residual posterior tilt after FNF could affect the anteroposterior localization of necrosis.

Comparative Short-Term Outcomes of Femoral Neck System (FNS) and Cannulated Screw Fixation in Patients with Femoral Neck Fractures: A Multicenter Study

Background

Femoral neck fractures need to be treated in their early stages with accurate reduction and stable fixation to reduce complications. The authors compared the early radiologic outcomes of femoral neck fractures treated with the recently introduced Femoral Neck System (FNS, Depuy-Synthes) with conventional cannulated screws (CS) in a multicenter design. Furthermore, the factors associated with early failure after FNS were analyzed.

Methods

The FNS group included 40 patients treated between June 2019 and January 2020, and the CS group included 65 patients treated between January 2015 and May 2019. The operation was performed in 3 university hospitals. Patient demographics, fracture classification, postoperative reduction quality, sliding distance of FNS or CS, union and time to union, and complication rates were examined. Logistic regression analysis was performed on candidate factors for early failure of the FNS group.

Results

The FNS group had a 90% union rate and a mean time to union of 4.4 months, while the CS group had similar results with an 83.1% union rate and a mean time to union of 5.1 months. In the subgroup analysis of Pauwels type III fractures, the union rates were 75.0% and 58.8% in the FNS and CS groups, respectively, and the time to union was significantly shorter in the FNS group with 4.8 months compared to 6.8 months in the CS group. Early failure rate within 6 months of FNS fixation was observed to be 10%, which included 3 reduction failures and 1 excessive sliding with a broken implant. Risk factors for early failure after FNS were identified as displaced fractures (Garden classification type III or IV), poor reduction quality, longer tip-apex distance, greater sliding distance, and 1-hole implants, of which sliding distance was the only significant risk factor in multivariate analysis.

Conclusions

In femoral neck fractures, FNS and CS did not show significant differences for short-term radiologic results. FNS resulted in shorter operative time than cannulated screw fixation and favorable outcomes in Pauwels type III femoral neck fractures. The FNS could be considered a reliable and safe alternative to CS when treating femoral neck fractures.

Increasing the angle between caudal screw and the transverse plane may aggravate the risk of femoral head necrosis by deteriorating the fixation stability in patients with femoral neck fracture

Necrosis of the femoral head is the main complication in femoral neck fracture patients with triangle cannulated screw fixation. Instant postoperative fixation instability is a main reason for the higher risk of femoral head necrosis. Biomechanical studies have shown that cross screw fixation can effectively optimize fixation stability in patients with proximal humerus fractures and pedicle screw fixation, but whether this method can also effectively optimize the fixation stability of femoral neck fractures and reduce the corresponding risk of femoral head necrosis has yet to be identified. In this study, a retrospective review of imaging data in femoral neck fracture patients was performed. The cross angle between the femoral neck and the caudal cannulated screw was reported; if the angle between the screw and the transverse plane increased, it was recorded as positive; otherwise, it was recorded as negative. Angle values and their corresponding absolute values were compared in patients with and without femoral head necrosis. Regression analysis identified potential risk factors for femoral head necrosis. Moreover, the biomechanical effect of the screw-femoral neck angle on fixation stability was also verified by numerical mechanical simulations. Clinical review presented significantly larger positive angle values in patients with femoral head necrosis, which was also proven to be an independent risk factor for this complication. Moreover, fixation stability progressively deteriorated with increasing angle between the caudal screw and the transverse plane. Therefore, increasing the angle between the caudal screw and the transverse plane may aggravate the risk of femoral head necrosis by deteriorating the fixation stability in patients with femoral neck fracture.

Comparison of young femoral neck fractures treated by femoral neck system, multiple cancellous screws and dynamic hip screws: a retrospectively comparison study

BACKGROUND

Implant choice for the fixation of femoral neck fracture is one of the most important management controversies. This study aims to evaluate and compare the short-term outcomes associated with the use of the Femoral Neck System (FNS), Multiple Cancellous Screws (MCS), and Dynamic Hip Screws (DHS) in treating femoral neck fractures in a young patient population.

METHODS

From June 2018 to June 2021, a total of 120 surgeries for a primary femoral neck fracture were retrospectively analyzed. This review encompassed demographic details of the patients and the mechanisms behind the injuries. Key surgical parameters such as operation duration, intraoperative blood loss, fluoroscopy duration, and hospital stay were meticulously documented. The employed surgical technique was described. All patients were followed up at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Avascular necrosis of the femoral head (AVN), nonunion, malreduction, implant failure or other complications were noted. The functional status at the last follow-up was assessed using the Harris functional scoring criteria.

RESULTS

There were 90 males and 30 females, with a mean age of 40.4 years. As to patient characteristics, there were no significant differences between the three groups. DHS group showed longer operation time(52.15 ± 4.80 min), more blood loss(59.05 ± 5.87 ml) and longer time of hospitalization(7.6 ± 0.90 d) than FNS group (39.65 ± 2.84 min, 45.33 ± 9.63 ml and 4.87 ± 0.48 d) and MCS group (39.45 ± 3.10 min, 48.15 ± 7.88 ml and 5.04 ± 0.49 d) (p < 0.05). In addition, the time of fluoroscopy in FNS group (15.45 ± 3.67) was less than that in MCS group (26.3 ± 4.76) and DHS group (27.1 ± 5.67) (p < 0.05). The cost of FNS group(44.51 ± 2.99 thousand RMB) was significantly higher than the MCS and DHS groups. The FNS, MCS and DHS groups showed a similar mean length of femoral neck shortening (LFNS) and Harris score. The FNS, MCS and DHS groups showed a similar mean rate of AVN and internal fixation failure.

CONCLUSIONS

Following successful fracture reduction, FNS, MCS, and DHS are effective for in the young femoral neck fractures. No difference was found in complications between the three groups. However, the reduced fluoroscopy time associated with FNS contributes to shorter operation durations. The adoption of minimally invasive techniques correlates with decreased blood loss and shorter hospital stays. Nevertheless, these advantages may be offset by the potential economic burden they impose.

Revision ratio after Femoral Neck System implantation for hip fracture treatment: a retrospective cohort analysis

The aim of the study is to determine the revision ratio after implantation of the femoral neck system (FNS) for the treatment of femoral neck fractures. A retrospective single center cohort analysis with a total of 71 patients who underwent the implantation of the FNS between December 2019 and December 2021, was performed. 31 males and 40 females were included. There was no exclusion based on BMI, ASA score, Garden classification or Pauwels classification. Primary outcome was the revision rate after FNS implantation. Secondary outcomes comprise the reason for revision surgery as well as the time toward revision surgery and the 30-day mortality. The revision ratio was 11 out of 71 patients (15.5%) with an average time to revision surgery of 10 months. Most common reason for revision was avascular necrosis (AVN) in 45.5%. Other reasons for revision surgery were implant failure due to a secondary fall on to the hip with the FNS implant in place, cut-out, cut-through and malunion in respectively 27.3%, 9%, 9% and 9% of the revision patients. The one- hole plate was used in 72% of the patients. Mean follow-up was 18.07 months (range 6-30 months). Full weight bearing instruction was given to 85.9% of the patients. Partial weight bearing in 14.1% of the patients. In conclusion, the FNS has similar revision ratio when used for femoral neck fractures compared to cannulated screw fixation in literature. The predominant reason for revision is AVN and implant failure with no difference between the use of the one- or-two-hole plate in this study.

Treatment of Pauwels III femoral neck fracture in young patients using biplane double support screw internal fixation technology based on X-ray image

Traditional treatment methods have certain limitations. In recent years, the technique of internal fixation with double-plane double-supported screws based on X-ray images has been proposed to improve the therapeutic effect. The main objective of this research was to examine the effectiveness of the X-ray image-based bi-planar double-braced screw internal fixation technique . During surgery, the procedure was determined based on X-ray images, followed by an open reduction procedure at the fracture site, and finally internal fixation using bi-planar double-support screws. All patients were successfully treated with X-ray image-based bi-planar double support screw fixation. After surgery, X-ray images showed a good reduction of the fracture site without significant loosening or failure of the internal fixation. At the postoperative follow-up, the patient's pain symptoms were significantly relieved, and no significant complications occurred during recovery.

Method for reconstructing femoral head blood supply by anastomosing the intraosseous artery

Background

The reconstruction of femoral head blood supply is crucial in the management of avascular necrosis and related conditions. This study presents a method for reconstructing the femoral head blood supply by anastomosing the intraosseous artery.

Methods

The femoral heads of six male Landrace swine were surgically exposed, and subcranial fractures of the femoral neck were intentionally created. Under microscopic guidance, the trophoblastic foramen of the posterior supporting artery was identified. Subsequently, a triangular bone window was carefully crafted to expose the intraosseous artery. Following the fixation of the femoral head, an anastomosis was performed between the intraosseous artery and the posterior inferior supporting artery located at the distal end of the fracture. The assessment of femoral head blood supply was conducted using Kirschner's pinhole and angiography techniques.

Results

The anastomotic intraosseous artery exhibited a vibrant red color, indicating adequate blood perfusion, and demonstrated pulsatile flow. Observation through pinholes in the surface of the femoral head revealed continuous blood flow. Angiography further confirmed the successful circulation, as the contrast agent entered the inferior retinacular artery branch originating from the deep femoral artery. The contrast agent then proceeded to enter the femoral head through the retinacular artery, reaching the anastomosis site of the intraosseous artery. Notably, the angiography also revealed the presence of visible internal branches, highlighting the establishment of a functional vascular network.

Discussion

The method of reconstructing the blood supply to the femoral head through anastomosis of the intraosseous artery enables utilization of the existing blood supply system within the femoral head. This study is just a preliminary study of this innovative technique that has the potential to prevent and/or treat femoral head necrosis following a femoral neck fracture. By restoring adequate blood flow to the affected area, this approach holds promise in preserving the viability and functionality of the femoral head, ultimately improving patient outcomes.

Failure after operative repair is higher for ballistic femoral neck fractures than for closed, blunt-injury fractures: a multicenter retrospective cohort study

Introduction

The purpose of this study was to describe the outcomes after operative repair of ballistic femoral neck fractures. To better highlight the devastating nature of these injuries, we compared a cohort of ballistic femoral neck fractures to a cohort of young, closed, blunt-injury femoral neck fractures treated with open reduction and internal fixation (ORIF).

Methods

Retrospective chart review identified all patients presenting with ballistic femoral neck fractures treated at three academic trauma centers between January 2016 and December 2021, as well as patients aged ≤50 with closed, blunt-injury femoral neck fractures who received ORIF. The primary outcome was failure of ORIF, which includes the diagnosis of non-union, avascular necrosis, conversion to total hip arthroplasty, and conversion to Girdlestone procedure. Additional outcomes included deep infection, postoperative osteoarthritis, and ambulatory status at last follow-up.

Results

Fourteen ballistic femoral neck fractures and 29 closed blunt injury fractures were identified. Of the ballistic fractures, 7 (50%) patients had a minimum of 1-year follow-up or met the failure criteria. Of the closed fractures, 16 (55%) patients had a minimum of 1-year follow-up or met the failure criteria. Median follow-up was 21 months. 58% of patients with ballistic fractures were active tobacco users. Five of 7 (71%) ballistic fractures failed, all of which involved non-union, whereas 8 of 16 (50%) closed fractures failed (p=0.340). No outcomes were significantly different between cohorts.

Conclusion

Our results demonstrate that ballistic femoral neck fractures are associated with high rates of non-union. Large-scale multicenter studies are necessary to better determine optimal treatment techniques for these fractures.

Level of evidence

Level III. Retrospective cohort study.

Early versus delayed weight bearing after internal fixation for femoral neck fracture in younger adults: A multicenter retrospective study

INTRODUCTION

Femoral neck fracture (FNF) is among the most common and devastating injuries that orthopedic surgeons encounter. However, the incidence of FNF is lower in younger adults than in elderly individuals. In elderly FNF patients, early weight bearing (EWB) is preferred to prevent loss of function and decreased activity. In younger adults, some surgeons decide on delayed-weight bearing (DWB) after surgery because EWB may cause femoral neck shortening. We aimed to compare the postoperative results (clinical outcome, radiological evaluation, and complications) of EWB and DWB after FNF surgery in younger adults.

METHODS

The study included 151 younger adults (age: ≤65 years at injury; nondisplaced, n = 100; displaced, n = 51) who underwent internal fixation at 11 university-affiliated hospitals in 2016-2020, and who were followed for ≥1 year. Patients were divided into the EWB (EWB in early postoperative period) and DWB (beginning weight bearing at 4 weeks after surgery) groups. The two groups were matched for age, and nondisplaced (EWB and DWB, both n = 24) and displaced (EWB and DWB, both n = 11) FNF were analyzed. The study items were age, sex, body mass index (BMI), Charlson Comorbidity Index (CCI), presence of diabetes, days waiting for surgery, fracture type, Parker mobility score (PMS) at last follow-up examination, pain (Numerical Rating Scale: NRS), radiological evaluation (femoral neck shortening, Canulated Cancellous screws (CCS) backout, and complications (nonunion, femoral head osteonecrosis).

RESULTS

The patient backgrounds of the nondisplaced and displaced types did not differ. The PMS was significantly higher in the DWB group at the last follow-up examination (nondisplaced: 8.00±2.20 vs. 6.67±2.22, p = 0.005, displaced: 8.67±0.89 vs. 6.91±2.77, p<0.001). NRS and the amount of femoral neck shortening were significantly lower in the DWB group (nondisplaced: 1.65±0.70 mm vs. 3.94±3.03 mm, p<0.001, displaced: 4.26± 2.64 mm vs. 8.91±5.69 mm, p<0.001). CCS backout did not differ between the groups. One case of each of nonunion and femoral head osteonecrosis were observed in the displaced EWB and DWB groups; these differences were not significant.

CONCLUSIONS

DWB after internal fixation for FNF in younger adults was associated with better outcomes than EWB.

Femoral neck shortening as a sequela of internal fixation for femoral neck fractures and its effect on the coronal alignment of the limb: a pilot study

INTRODUCTION

Femoral neck shortening is a common phenomenon following osteosynthesis for femoral neck fractures, which was shown to have a negative effect on hip function. There is paucity of literature on the effect of shortening on the ipsilateral limb mechanical axis and knee coronal alignment. We hypothesized that postoperative femoral neck shortening can alter the limb's mechanical axis into valgus.

METHODS

Of 583 patients screened, 13 patients with severe neck shortening (< 10 mm) following femoral neck fracture fixation, were found eligible and agreed to participate. A full-length lower limb radiographs were obtained and radiographic parameters (offset, neck-shaft angle, HKA, mLPFA, mDLFA, mMPTFA, MAD, MAD-r) as well as functional scores were obtained.

RESULTS

Statistically significant differences in mechanical axis deviation ratio (MAD-r) were found between the ipsilateral and the contralateral extremities (0.41 ± 0.16 versus 0.55 ± 0.11, p = 0.03). A correlation between femoral neck length differences and MAD was not statistically significant although a tendency towards lateral deviation of the mechanical axis was noted (r = - 0.5, p = 0.077). A negative correlation was found between a greater difference in the femoral neck length and the SF12 score, both in the physical and the mental parts (r = - 0.69, p = 0.008; r = - 0.58, p = 0.035, respectively).

CONCLUSION

We found a more lateralized mechanical axis in limbs that demonstrated post-operative ipsilateral femoral neck severe shortening. These findings may provide a possible explanation and rationale for knee pain and perhaps for the development of knee osteoarthritis as a sequalae of femoral neck shortening. Further investigation and larger cohort, long-term studies are needed to further explore this hypothesis.

Morphological characteristics of femoral neck fractures in young and middle-aged population: a retrospective descriptive study

BACKGROUND

A understanding of morphological characteristics are important to femoral neck fractures (FNFs) resulting in high rates of complications in the young and middle-aged adults and the detailed data is lack in the literature. We aimed to report on the detailed morphological characteristics and the relationship between them in young and middle-aged adults with femoral neck fractures (FNFs).

METHODS

The postoperative CT images of one hundred and fifty-two adults with FNFs were retrospectively reviewed. After image standardization, morphological characteristics including fracture orientation, cortex comminution, and intraosseous bone defects were measured and analyzed. Additionally, the distribution and correlation of these morphological features were analyzed using Pauwels classification, the right angle of the neck axis (VNA) classification, and the anteromedial oblique angle (AMA).

RESULTS

Pauwels III fractures accounted for approximately half (55.2%) of the FNFs analyzed. Pauwels II and III could be detected in all four VNA types, and the distribution of the Pauwels types in VNA classification showed significant differences (χ2 = 106.363, p < 0.001). The VNA (9.0° ± 12.1) showed positive correlation with the neck-shaft angle (139.5° ± 6.3) and modified Pauwels angle (49.8° ± 10.6) (r = 0.441, r = 0.855, all p < 0.001). Cortical comminutions were commonly observed in the posterior (86.7%) and the inferior (80.7%). AMAs within the cases without posterior and inferior cortex comminutions were significantly larger than those with comminution (t = 2.594, 2.1196; p = 0.01, 0.036), but no difference could be detected after the AMA being divided into three groups (< 85°, 85°-95°, > 95°). The MPA, VNA and AMA of the group with an intraosseous defect were significantly different compared with those without (t = 2.847, 2.314, 2.268; p = 0.005, 0.022,0.025). The incidence of intraosseous defects within the groups with coronal and axial cortex comminutions were significantly higher than those within the groups without comminutions (χ2 = 34.87, 25.303; p < 0.001).

CONCLUSIONS

The present study highlights the morphological diversity and complexity within FNFs in young and middle-aged adults, which allows for more accurate simulation of FNF patterns in the future biomechanical studies.

Consensus and Equipose in the Management of Military Trainee Femoral Neck Stress Fractures: A Survey of Military Surgeons

BACKGROUND

Femoral neck stress fractures (FNSFs) are a unique injury pattern not commonly treated in the civilian trauma population; however, it is particularly high with military trainees engaged in basic combat training. To date, no study has surveyed a population of military orthopedic surgeons on treatment preferences for military service members (SMs) with FNSF.

QUESTIONS

We aim to evaluate the extent of clinical equipoise that exists in the management of these injuries, hypothesizing that there would be consensus in the factors dictating surgical and non-surgical intervention for FNSF.

PATIENTS AND METHODS

A 27-question survey was created and sent to U.S. military orthopedic surgeon members of the Society of Military Orthopaedic Surgeons. The survey was designed in order to gather the experience among surgeons in treating FNSF and identifying variables that play a role in the treatment algorithm for these patients. In addition, seven detailed, clinical vignettes were presented to further inquire on surgeon treatment preferences. Binomial distribution analysis was used to evaluate for common trends within the surgeon's treatment preferences.

RESULTS

Seventy orthopedic surgeons completed the survey, the majority of whom were on active duty status in the U.S. Military (82.86%) and having under 5 years of experience (61.43%). Majority of surgeons elected for a multiple screw construct (92.86%), however the orientation of the multiple screws was dependent on whether the fracture was open or closed. Management for compression-sided FNSF involving ≥50% of the femoral neck width, tension-sided FNSF, and stress fractures demonstrating fracture line progression had consensus for operative management. Respondents agreed upon prophylactic fixation of the contralateral hip if the following factors were involved: Complete fracture (98.57%), compression-sided fracture line >75% (88.57%), compression-sided fracture line >50-75% with hip effusion (88.57%), contralateral tension-sided fracture (87.14%), and compression-sided fracture line >50-75% (84.29%). An FNSF < 50% on the contralateral femoral neck or a hip effusion was indeterminate in surgeons indicating need for prophylactic fixation. Majority of surgeons (77.1%) utilized restricted toe-touch weight-bearing for postoperative mobility restrictions.

CONCLUSIONS

Consensus exists for surgical and non-surgical management of FNSF by U.S. military orthopedic surgeons, despite the preponderance of surgeons reporting a low annual volume of FNSF cases treated. However, there are certain aspects in the operative and non-operative management of FNSF that are unanimously adhered to. Specifically, our results demonstrate that there is no clear indication on the management of FNSF when an associated hip effusion is involved. Additionally, the indications for surgically treating contralateral FNSF are unclear.

LEVEL OF EVIDENCE

IV.

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.

Health economics for intra-capsular hip fractures undertaking fixation

BACKGROUND

Hip fracture is a common musculoskeletal injury in the elderly requiring surgery worldwide. The operative mainstay of intra-capsular hip fractures is arthroplasty with a smaller proportion for fixation.

AIM

To determine the most beneficial method of fixation for patients with intra-capsular hip fractures.

METHODS

A registered audit from 2012-2018 was conducted on all intra-capsular hip fractures treated with 2 commonly used fixation methods. Patient notes, electronic records and clinical codes for cost benefit were evaluated. A validated quality of life measure was collected at least 1 year after surgery.

RESULTS

A total of 83 patients were identified with intra-capsular fractures undergoing fixation during the retrospective period. There were 47 cannulated cancellous screw and 36 sliding hip screw fixations with the case mix comparable for age, gender, co-morbidities and fracture configuration. There was no significant difference in blood loss, tip apex distance, radiation exposure, length of stay, radiological union time, collapse, avascular necrosis or re-operation between fixation methods. Logistic regression analysis demonstrated displaced intracapsular hip fractures correlated significantly with an undesirable outcome conferring a relative odds ratio of 7.25. There were 9 (19%) and 4 (11%) patients respectively, who required re-operation. There was no significant difference in health resource group tariff and implant cost with comparable EQ-5D and visual analogue scores.

CONCLUSION

No significant advantage was identified with differing fixation type, but irrespective there were a high number of patients requiring re-operation. This was predicted by initial fracture displacement and patient age. Arthroplasty may need to be carefully considered for health economics and patient benefit.

Femoral neck system versus multiple cannulated screws for the fixation of Pauwels classification type II femoral neck fractures in older female patients with low bone mass

BACKGROUND

Femoral neck fractures in older adult patients are a major concern and often necessitate surgical intervention. This study compared the clinical outcomes of 2 surgical techniques: the femoral neck system (FNS) and cannulated compression screws (CCSs).

METHODS

A total of 40 female patients (mean age 73.50 ± 11.55 years) with femoral neck fractures of Pauwels classification type II and receiving surgical fixation between 2020 and 2022 were enrolled. The patients were categorized into an FNS group (n = 12) or a CCS group (n = 28), and surgical duration, intraoperative blood loss, length of hospital stay, and incidence of postoperative adverse events were analyzed.

RESULTS

No significant intergroup differences in demographic characteristics were discovered. The mean surgical duration for all patients was 52.88 ± 22.19 min, with no significant difference between the groups. However, the FNS group experienced significantly higher intraoperative blood loss (P = 0.002) and longer hospital stay (P = 0.023) than did the CCS group. The incidence of osteonecrosis was higher in the CCS group, whereas the incidence of nonunion or malunion was higher in the FNS group. The surgical method did not appear to be a significant risk factor. The main risk factor for revision surgery was longer duration until the first adverse event (P = 0.015).

CONCLUSION

The FNS does not appear to provide superior surgical outcomes compared with CCSs in older adult women with Pauwels classification type II femoral neck fractures. A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery.

Femoral neck system as a safe alternative to cannulated compression screw and dynamic hip screw in femoral neck fractures: an early comparative study

INTRODUCTION

The femoral neck system (FNS) is a safe alternative to cannulated compression screw (CCS) and dynamic hip screw (DHS) in femoral neck fractures.

METHODS

A dual-centre retrospective cohort study was performed on femoral neck fractures (AO type 31-B) treated with closed reduction and internal fixation using FNS, DHS or CCS between April 2016 and April 2020. Exclusion criteria were as follows: patients aged below 16 years; chronic fractures beyond 7 days; pathological fractures; fracture extension to the intertrochanteric region or ipsilateral neck and shaft fractures; and open fractures. A total of 85 patients were identified: FNS (n = 28), DHS (n = 29) and CCS (n = 28).

RESULTS

The FNS and CCS groups had a lower Garden and Pauwels classification compared to the DHS group (both P < 0.001). Both FNS and CCS groups were comparable in postoperative orthopaedic complications (10.7% [n = 3] vs. 3.6% [n = 1], adjusted P = 0.321). The DHS group had more postoperative orthopaedic complications than the FNS group, but this was not statistically significant (27.6% [n = 8] vs. 10.7% [n = 3], adjusted P = 0.321). There were no significant differences in median time to radiological union or median femoral neck shortening at union (both P > 0.05) among the three groups.

CONCLUSION

The new DePuy Synthes FNS is a safe alternative to CCS with comparable complication rates for femoral neck fractures that are less displaced and more stable. The FNS also appears to be a safe alternative to DHS in the fixation of femoral neck fractures for the few cases of high-energy femoral neck fractures.

Compressive buttress compared with off-axial screw fixation for vertical femoral neck fractures in young adults: a prospective, randomized controlled trial

BACKGROUND

To compare the clinical outcomes of compressive buttress screw (CBS) fixation, a novel screw fixation strategy, to off-axial screw fixation (off-axial partial threaded cannulated screw, OPTCS) for vertical femoral neck fractures (FNFs) in young adults.

METHODS

A total of 146 adults younger than 55 years old with high-energy Pauwels type III FNFs were randomized to receive CBS fixation or OPTCS fixation. Primary outcomes were complication rates, including fixation failure, fracture nonunion, and avascular necrosis of the femoral head (ANFH) at 24 months after treatment. Fixation loosening, femoral neck shortening and varus collapse, patient function and quality of life using the Harris hip score (HHS), and EuroQol-5 dimensional-5 levels (EQ-5D-5L) questionnaire (including EQ-5D-5L and EQ-VAS) were assessed as secondary outcomes at 24 months.

RESULTS

CBS and OPTCS fixation groups were similar with regard to demographics at baseline. At 24 months, patients in the CBS fixation cohort had a significantly lower rate of fixation failure (10.5% vs. 25.0%, p = 0.041) and fracture nonunion (1.8% vs. 18.3%, p = 0.003) compared with patients who received OPTCS fixation. There was no difference in rate of ANFH (7.0% vs. 11.7%, p = 0.389) between groups. Additionally, patients managed with CBS fixation showed significantly less fixation loosening (19.3% vs. 58.3%, p < 0.001), less severe femoral neck shortening and varus collapse (10.5% vs. 25.0%, p = 0.007), higher HHS (93 vs. 83, p = 0.001) and more excellent grade (68.4% vs. 36.7%, p = 0.008), higher EQ-5D-5L (0.814 vs, 0.581, p < 0.001) and EQ-VAS (85 vs. 80, p = 0.002).

CONCLUSION

CBS screw fixation confers significantly lower complication rate in addition to higher functional and quality of life outcomes for young adults with high-energy FNF compared with OPTCS fixation.

TRIAL REGISTRATION

This prospective, randomized controlled trial was approved by the institutional review board of our center, Ethics Committee of Shanghai sixth people's Hospital, and registered at www.chictr.org.cn (Approval Number: ChiCTR1900026283; Registered 29 September 2019-Retrospectively registered, https://www.chictr.org.cn/showproj.html?proj=43164 ).

[Translated article] The configuration of the screws in the osteosynthesis of fractures of the femoral neck does not influence the functional or mechanical outcomes

BACKGROUND AND OBJECTIVE

Synthesis with cannulated screws is one of the accepted methods in femoral neck fractures, although its optimal configuration is a subject in continuous debate. The main objective was to compare the results of the patient with a femoral neck fracture fixed with three screws in triangle and inverted triangle configuration in the frontal plane.

MATERIALS AND METHODS

Retrospective and comparative study of 53 patients with femoral neck fracture, operated between 2015 and 2022 with fixation with three cannulated screws, 22 with a triangle configuration (triangle group) and 31 in an inverted triangle (inverted triangle group). Functionality was evaluated using the modified Merlé d'Aubigné scale, walking ability using the Koval scale, as well as postoperative complications.

RESULTS

On the Merlé d'Aubigné scale, the mean score was 16.7 in the triangle group and 16.1 in the inverted triangle group (p=.259). On the Koval scale, a significant decrease was observed, going from 1.6 preoperative mean to 2.2 after surgery (p=.000), finding no differences between groups. There were six postoperative complications in the triangle group and three in the inverted triangle group (p=.140).

CONCLUSION

The configuration of the screws in the femoral neck, both in the form of a triangle and an inverted triangle, did not influence the functional or mechanical outcomes of the patients with a femoral neck fracture fixed with three cannulated screws.

Multidimensional Fluoroscopy to Assess Closed Reduction in Displaced Young Femoral Neck Fractures: A Report of 3 Cases

CASE

The authors present 3 physiologically young patients with displaced femoral neck fractures who underwent initial closed reduction and provisional fixation. Multidimensional fluoroscopy was used to assess fracture reduction before definitive fixation, with 1 patient requiring an open approach because of inadequate fracture reduction after closed attempts.

CONCLUSION

Displaced femoral neck fractures in young patients remain difficult injuries to treat. Reduction quality is a significant predictor of patient outcomes. Intraoperative multidimensional fluoroscopy provides treating surgeons with a tool to assess fracture reduction after closed reduction maneuvers and allows for intraoperative treatment adjustment as needed.

The configuration of the screws in the osteosynthesis of fractures of the femoral neck does not influence the functional or mechanical outcomes

BACKGROUND AND OBJECTIVE

Synthesis with cannulated screws is one of the accepted methods in femoral neck fractures, although its optimal configuration is a subject in continuous debate. The main objective was to compare the results of the patient with a femoral neck fracture fixed with three screws in triangle and inverted triangle configuration in the frontal plane.

MATERIALS AND METHODS

Retrospective and comparative study of 53 patients with femoral neck fracture, operated between 2015 and 2022 with fixation with three cannulated screws, 22 with a triangle configuration (triangle group) and 31 in an inverted triangle (inverted triangle group). Functionality was evaluated using the modified Merlé d'Aubigné scale, walking ability using the Koval scale, as well as postoperative complications.

RESULTS

On the Merlé d'Aubigné scale, the mean score was 16.7 in the triangle group and 16.1 in the inverted triangle group (P=.259). On the Koval scale, a significant decrease was observed, going from 1.6 preoperative mean to 2.2 after surgery (P=.000), finding no differences between groups. There were six postoperative complications in the triangle group and three in the inverted triangle group (P=.140).

CONCLUSION

The configuration of the screws in the femoral neck, both in the form of a triangle and an inverted triangle, did not influence the functional or mechanical outcomes of the patients with a femoral neck fracture fixed with three cannulated screws.

The floating hip injury: a descriptive study and case-control analysis

PURPOSE

A "floating hip" (FH) injury is a rare injury describing the simultaneous ipsilateral fracture of the femur and pelvis or acetabulum (P/A). We describe our experience with patients presenting with FH injuries and compare them to controls with similar P/A fractures but without femoral involvement.

METHODS

Medical records and radiographs of FH patients and controls presenting to our tertiary centre between 2015 and 2020 were reviewed. Follow-up data from outpatient clinical records were also extracted. The control group were extensively matched by age, sex, body mass index, fracture classification and energy of injury.

RESULTS

From 1392 recorded P/A fractures, 42 FH cases were identified (average age 39 years, 78.6% males). The most common femoral fracture was the midshaft (35.7%), followed by the neck of femur (26.2%). 90.5% of FH injuries were due to high-energy mechanisms. 64.3% of P/A fractures, and 100% of femoral fractures were managed surgically. Compared to controls, FH cases were more likely to have additional orthopaedic injuries (73.8% vs. 40.5%, p = 0.002), more total theatre admissions (mean 2.5 vs. 1.19, p < 0.001), longer hospital stays (28.3 vs. 14.9 days, p = 0.02), and a higher rates of post-op complications (53.8% vs. 20%, p = 0.025).

CONCLUSIONS

We report differences in the presentation, management, and outcomes of FH injuries versus controls, even after extensive matching for confounders. These differences may inform future treatment strategies for the FH injury.

Proximal femoral bionic nail-a novel internal fixation system for the treatment of femoral neck fractures: a finite element analysis

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.

Clinical observation of Gofried positive buttress reduction in the treatment of young femoral neck fracture: A systematic review and meta-analysis

BACKGROUND

Femoral neck fractures in young adults(<65 years), have always been a difficult problem, characterized by high rates of nonunion and avascular necrosis (AVN). The clinical efficacy of anatomical reduction and non-anatomical reduction methods needs to be supported by clinical data. Therefore, we conduct a meta-analysis on the clinical efficacy of different reduction methods to better guide clinical practice.

METHODS

Relevant studies published using internal fixation to treat femoral neck fracture in several databases were searched. The outcomes sought included Harris score and the rate of AVN, nonunion and femoral neck shortening (<5 mm). Included studies were assessed for methodological bias and estimates of effect were calculated. Potential reasons for heterogeneity were explored.

RESULTS

The clinical results showed that compared with the anatomical reduction and positive buttress, there is no significant difference in the rate of AVN (OR = 0.87, 95%CI: 0.55-1.37, P = .55), nonunion (OR = 0.54, 95%CI: 0.21-1.41, P = .21), femoral neck shortening (<5 mm) (OR = 1.03,95%CI: 0.57-1.86, P = .92), the Harris score (MD = -0.28, 95%CI: -1.36-0.80, P = .61) and the excellent and good rate of Harris score (OR = 1.73, 95%CI: 0.84-3.56, P = .61). However, compared with negative buttress, the rate of AVN (OR = 0.62, 95%CI: 0.38-1.01, P = .05), nonunion (OR = 0.34, 95%CI: 0.12-1.00, P = .05) and femoral neck shortening (<5 mm) (OR = 0.27, 95%CI: 0.16-0.45, P < .00001) were significantly lower, and the Harris score (MD = 6.53, 95%CI: 2.55 ~ 10.51, P = .001) was significantly better in positive buttress.

CONCLUSIONS

In the case of difficult to achieve anatomical reduction, for young patients (< 65 years) with femoral neck fracture, reduction with positive buttress can be an excellent alternative and negative buttress should be avoided as much as possible.

Outcomes of three cannulated screws in a modified triangular transverse configuration for fixation of intra-capsular femoral neck fractures

BACKGROUND

Intra-capsular femoral neck fractures (FNF) are commonly encountered in trauma settings and are associated with high rates of morbidity and mortality. One of the most used methods of FNF treatment is the use of multiple cannulated screws. Many different screw constructs are reported in the literature, with no evidence of superiority of one construct over others. We present a series of patients treated by one senior surgeon with three cannulated screws positioned in a specific configuration.

MATERIALS AND METHODS

We conducted a retrospective monocentric analysis. All charts of patients hospitalized between January 2004 and June 2022 for an intra-capsular femoral neck fracture treated by three cannulated screws by the same senior surgeon were retrieved and analyzed. The clinical and radiological evaluations were performed by two independent researchers. Functional status of patients was assessed using the modified Harris Hip score (mHHS). Complications such as secondary displacement, non-union, avascular necrosis (AVN) and femoral neck shortening were all recorded.

RESULTS

A total of 38 patients met the inclusion criteria. There were 17 males and 21 females with an average age of 66.3 ± 13.6 years and a follow-up period of 16 ± 20 months. Bone union was observed in 34 (89.5%) patients. Mild shortening was observed in two patients (5.2%) with no functional limitation. Four patients (10.5%) underwent reoperations, three due to another fall and one due to AVN four years post-fracture fixation.

CONCLUSION

In our series, we demonstrate that the use of three cannulated screws in a triangular transverse configuration for fixation of intra-capsular femoral neck fractures provides excellent results with low rates of femoral neck shortening, AVN or non-union.

Factors associated with early failure of the femoral neck system (FNS) in patients with femoral neck fractures

BACKGROUND

Femoral neck system (FNS) is a new type of internal fixation system which has been widely used for treating femoral neck fractures (FNFs).Compared with other internal fixation methods, FNS is minimally invasive and stable, and often achieves satisfactory short-term efficacy.Early failure of FNS (EFFNS) is not uncommon, however, there are few literatures and reports on factors associated with EFFNS.This study aimed to survey the prevalence and risk factors of EFFNS.

METHODS

We retrospectively analysed 62 patients with FNFs and underwent FNS fixation between 2019 and 2021. Demographic data, clinical characteristics, radiographic features and treatment process were described. Multifactor logistic regression analysis was used to analyse the different influencing factors.

RESULTS

Out of the 62 FNFs patients, 10 patients (16.1%) developed EFFNS, including 6 cases of severe femoral neck shortening, 2 cases of screw-out, 1 case of avascular necrosis of the femoral head and 1 case of nonunion. In the failure group, all patients were younger than 65 years old, which was significantly higher than 59.6% in the healing group (P = 0.012). There were no significant differences in sex(P = 0.490), BMI (P = 0.709), injured side (P = 0.312), injury mechanism (P = 0.617), reduction method(P = 0.570),femoral neck-shaft angle(P = 0.545), Pauwels classification (P = 0.564) and Garden classification (P = 0.195). Moreover, we not found that Garden classification (P = 0.464) and age (P = 0.128) were statistically significant risk factors for EFFNS at multivariate analysis.

CONCLUSION

In this study, sex, BMI, injury side, injury mechanism, reduction method, Pauwels angle, femoral neck-shift angle, Pauwels classification and Garden classification were excluded as EFFNS risk factors. Moreover, our study demonstrated that age and Garden classification were not significant risk factors at multivariate analysis.

TRIAL REGISTRATION

ChiCTR, ChiCTR2100051360. Registered on 21 September, 2021. https://www.chictr.org.cn/index.aspx .

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.

Complications and associated risk factors after surgical management of proximal femoral fractures

Aims

This work aimed at answering the following research questions: 1) What is the rate of mechanical complications, nonunion and infection for head/neck femoral fractures, intertrochanteric fractures, and subtrochanteric fractures in the elderly USA population? and 2) Which factors influence adverse outcomes?

Methods

Proximal femoral fractures occurred between 1 January 2009 and 31 December 2019 were identified from the Medicare Physician Service Records Data Base. The Kaplan-Meier method with Fine and Gray sub-distribution adaptation was used to determine rates for nonunion, infection, and mechanical complications. Semiparametric Cox regression model was applied incorporating 23 measures as covariates to identify risk factors.

Results

Union failure occured in 0.89% (95% confidence interval (CI) 0.83 to 0.95) after head/neck fracturs, in 0.92% (95% CI 0.84 to 1.01) after intertrochanteric fracture and in 1.99% (95% CI 1.69 to 2.33) after subtrochanteric fractures within 24 months. A fracture-related infection was more likely to occur after subtrochanteric fractures than after head/neck fractures (1.64% vs 1.59%, hazard ratio (HR) 1.01 (95% CI 0.87 to 1.17); p < 0.001) as well as after intertrochanteric fractures (1.64% vs 1.13%, HR 1.31 (95% CI 1.12 to 1.52); p < 0.001). Anticoagulant use, cerebrovascular disease, a concomitant fracture, diabetes mellitus, hypertension, obesity, open fracture, and rheumatoid disease was identified as risk factors. Mechanical complications after 24 months were most common after head/neck fractures with 3.52% (95% CI 3.41 to 3.64; currently at risk: 48,282).

Conclusion

The determination of complication rates for each fracture type can be useful for informed patient-clinician communication. Risk factors for complications could be identified for distinct proximal femur fractures in elderly patients, which are accessible for therapeutical treatment in the management.

Superior short-term outcomes of FNS in combination with a cannulated screw in treating femoral neck fractures

BACKGROUND

This study aimed to evaluate the clinical efficacy of the femoral neck system alone or in combination with a cannulated screw compared with other internal fixation methods for treating femoral neck fractures. We further investigated the predictive effects of tip-apex distance (TAD) on clinical efficacy.

METHODS

Data from 129 young adults with femoral neck fractures followed up at The Second Affiliated Hospital of Fujian Medical University between January 2016 and June 2022 were retrospectively collected. The patients were categorized into four groups based on the different internal fixation methods. Analysis and comparisons of the four group were performed according to age, ASA score, operation time, blood loss, fracture classification, fracture healing time, Harris score, TAD value, presence of complications (osteonecrosis of the femoral head, screw failure, and femoral neck shortening), and changes in the neck-shaft angle.

RESULTS

All 129 patients were followed up for at least one year. The group who received treatment with the femoral neck system combined with a cannulated screw exhibited the shortest fracture healing time. Differences were observed in the change of neck-shaft angle among the four groups (P < 0.001), with the smallest change observed in the aforementioned group (0.76 ± 0.54°). The femoral neck shortening was also lower in groups with the femoral neck system or combined with a cannulated screw. At the last follow-up surgery, the combined treatment group achieved the highest HHS score. Subgroup analysis revealed that when the TAD was less than 25 and 49 mm for the femoral neck system and combined groups, respectively, there was less femoral neck shortening, less change in the neck-shaft angle, and a higher HHS score.

CONCLUSIONS

The femoral neck system alone or combined with a cannulated screw demonstrated better short-term efficacy in the treatment of femoral neck fractures. Furthermore, TAD may serve as a predictive indicator of the potential success of femoral neck fracture treatment.

Comparison of reconstruction nails versus dual implants in the treatment of ipsilateral femoral neck and shaft fractures in adults: a meta-analysis and systematic review

OBJECTIVE

There is no consensus on the optimal treatment for ipsilateral femoral neck and shaft fractures. This meta-analysis aims to assess the effectiveness of reconstruction nails and dual implants in treating ipsilateral femoral neck and shaft fractures to provide a basis for decision-making when selecting the optimal approach.

METHODS

Relevant articles were retrieved from Pubmed, Embase, and Cochrane databases using the keywords "neck of femur", "shaft" and "fracture fixation" from inception until November 17, 2022. The screening process of the studies was conducted independently by two assessors, who assessed each study's eligibility and two assessors assessed the quality. Then compared differences in outcome measures using RevMan 5.3 software.

RESULTS

A total of ten retrospective cohort studies were included. There were no significant differences in union time, union rate, union-related complications (malunion, nonunion, delayed union) of femoral neck and shaft fractures, osteonecrosis of the femoral head, and functional outcomes (Friedman-Wyman scoring system) (P > 0.05).

CONCLUSION

Our pooled estimates indicated that reconstruction nails and dual implants for ipsilateral femoral neck and shaft fractures could yield satisfactory surgical results, and that there is no difference between the two treatment methods.

TRIAL REGISTRATION

This meta-analysis was registered on the PROSPERO website (registration number: CRD42022379606).

Safe range of femoral neck system insertion and the risk of perforation

BACKGROUND

Internal fixation of the femoral neck carries a risk of perforation due to the presence of the isthmus of the femoral neck. At present, there are few studies on the safe and risk zones of the femoral neck system (FNS) implantation. This study aimed to recommend the safe range of injection of FNS in the lateral wall of the proximal femur, parallel to the axis of the femoral neck, during FNS treatment of femoral neck fracture (FNF).

METHODS

Femoral computed tomography (CT) data of 80 patients (male: 40; female: 40) who met the inclusion criteria were collected. Mimics 21.0 software was used to complete the modeling. 3-Matic 13.0 software was used to establish the axis of the femoral neck and its vertical plane, perform the cutting of the femoral neck, and project it on the vertical plane of the femoral neck axis. After matching a rectangle for each projection map, all sample sizes (80 cases) were standardized and superimposed to obtain gradient maps of the safe zone (SZ) and dangerous zone (RZ), thereby securing edge key points and safe FNS insertion range.

RESULTS

In the 80 samples, the mean diameter of the smallest femoral neck section was 33.87 ± 2.32 mm for men and 29.36 ± 1.92 mm for women. All 80 femoral necks had safe and risky areas. The SZ/S × 100% was 77.59 (± 2.22%), and the RS/S × 100% was 22.39% (± 2.22%). The risk area was composed of four parts: (1), (2), (3), and (4), respectively, corresponding to 3.45 ± 1.74%, 5.51 ± 2.63%, 6.22 ± 1.41%, and 7.22 ± 1.39%. Four marginal key points, perforation risk, and safe ranges (SR) of FNS were analyzed on the lateral wall of the femoral neck.

CONCLUSIONS

The SR of FNS placement was recommended by digital simulation. In addition, Regions (3) and (4) posed a higher risk of penetrating the cortex. Using the gradient map of RZ for preoperative evaluation is recommended to avoid iatrogenic perforation.

Clinical application of modified hip joint lateral position in femoral neck fracture

BACKGROUND

To show the femoral neck better in hip lateral view of X-ray, we design a modified hip lateral view and then investigate the value in femoral neck fractures.

METHODS

CT images of 10 normal hip joints for 3D reconstruction were selected, the Mimics Medical 21.0 was used, and rotating the proximal femur was to find the most suitable angle for showing the femoral neck well, designed the modified lateral view according to this angle. We collected 35 healthy cases and 35 femoral neck fractures as the normal and fracture group. And two groups were all taken hip anteroposterior view, cross-table lateral view and modified lateral view, which were analyzed by two radiologists to score the anatomical structures of the articular surface, femoral head, head neck junction, femoral neck, basal region and intertrochanteric region. Friedman test was used to analyze the score of femoral neck at different angles. T test and Wilcoxon signed-rank test were to compare inter-groups.

RESULTS

The modified lateral view was designed as follows: The subjects were supine, with the sagittal axis biased toward the healthy side at an angle of approximately 20° to the long axis of the examination table, the hip joint flexed at 45°, the lower extremity abducted at 40°, the centerline inclined 45° toward the head and the centerline aligned with the center of the groin. The modified lateral view showed the femoral head, head neck junction and femoral neck more clearly than the cross-table lateral view, but the cross-table lateral view showed the femoral neck basal and intertrochanteric region better. In addition, the time of taking the modified lateral view was significantly less than the cross-table lateral view (normal group: 0.789 min ± 0.223 vs 0.623 min ± 0.207, P < 0.001; fracture group: 1.131 min ± 0.362 vs 0.946 min ± 0.390, P < 0.001).

CONCLUSIONS

The modified lateral view can obtain a standard sagittal image of femoral neck, which can show the dislocation and angulation of the sagittal femoral neck fracture clearly, and improve the accuracy of diagnosis. And it is more convenient and easier for patients to cooperate, which is worthy promoting and applying in clinical work.