Intracapsular Femoral Neck Fractures-A Surgical Management Algorithm

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.

Biomechanical Comparison between Inverted Triangle and Vertical Configurations of Three Kirschner Wires for Femoral Neck Fracture Fixation in Dogs: A Cadaveric Study

The purpose of this study was to compare single-cycle axial load and stiffness between inverted triangle and vertical configurations of three Kirschner wires (K-wires) for femoral neck fracture fixation in small dog cadaveric models. In each of the eight cadavers, the basilar femoral neck fracture model was prepared on both sides of the femur. One side of the femur was stabilized with three 1.0 mm K-wires of an inverted triangle configuration (group T), and the other femur was stabilized with a vertical configuration (group V). Postoperatively, the placement of the K-wires was evaluated with radiographic and computed tomography (CT) images, and static vertical compressive loading tests were performed. The mean yield load and the lateral spread were significantly higher in group T compared to group V (p = 0.023 and <0.001). On the cross-section of femoral neck at the level of the fracture line, the surface area between K-wires was significantly larger (p < 0.001) and the mean number of cortical supports was significantly higher in group T (p = 0.007). In this experimental comparison, the inverted triangle configuration of three K-wires was more resistant to failure under axial loading than the vertical configuration for canine femoral neck fracture fixation.

Proportion of stable femoral neck fracture types in different age groups: a population-based study

OBJECTIVE

The treatment and incidence of femoral neck fracture (FNF) in older patients is controversial. We investigated the new AO (Arbeitsgemeinschaft für Osteosynthese) classification in patients with FNF by age to determine the proportions of stable fracture and change trends according to patients' age.

METHODS

We divided patients with FNF hospitalized in Xi'an Honghui Hospital from 2018 to 2020 into five groups according to age: young (<50 years), middle-aged (50-59 years), young-elderly (60-69 years), middle-elderly (70-79 years), and very elderly (≥80 years) groups. We retrospectively collected data of patients' sex, admission date, fracture side, mechanism of injury, and new AO classification.

RESULTS

In total, 2071 patients were included for analysis, with 1329 women (64.2%); 1106 patients (53.4%) had left-side fracture. The main mechanism of injury was falling. In the young-elderly, middle-elderly, and very-elderly groups, 33.3%, 29.2%, and 24.1% had stable fracture type, respectively). The proportion of patients with FNF did not show a change trend by age during the 3-year investigation period.

CONCLUSION

In our study, the proportion of older patients with FNF did not increase, and as many as a third of patients with FNF aged 50 to 70 years had stable fracture.

Direct Anterior versus Lateral Approach for Femoral Neck Fracture: Role in COVID-19 Disease

Background: During the COVID-19 emergency, the incidence of fragility fractures in elderly patients remained unchanged. The management of these patients requires a multidisciplinary approach. The study aimed to assess the best surgical approach to treat COVID-19 patients with femoral neck fracture undergoing hemiarthroplasty (HA), comparing direct lateral (DL) versus direct anterior approach (DAA). Methods: A single-center, observational retrospective study including 50 patients affected by COVID-19 infection (30 males, 20 females) who underwent HA between April 2020 to April 2021 was performed. The patients were allocated into two groups according to the surgical approach used: lateral approach and anterior approach. For each patient, the data were recorded: age, sex, BMI, comorbidity, oxygen saturation (SpO2), fraction of the inspired oxygen (FiO2), type of ventilation invasive or non-invasive, HHb, P/F ratio (PaO2/FiO2), hemoglobin level the day of surgery and 1 day post operative, surgical time, Nottingham Hip Fractures Score (NHFS) and American Society of Anesthesiologists Score (ASA). The patients were observed from one hour before surgery until 48 h post-surgery of follow-up. The patients were stratified into five groups according to Alhazzani scores. A non-COVID-19 group of patients, as the control, was finally introduced. Results: A lateral position led to a better level of oxygenation (p < 0.01), compared to the supine anterior approach. We observed a better post-operative P/F ratio and a reduced need for invasive ventilation in patients lying in the lateral position. A statistically significant reduction in the surgical time emerged in patients treated with DAA (p < 0.01). Patients within the DAA group had a significantly lower blood loss compared to direct lateral approach. Conclusions: DL approach with lateral decubitus seems to preserved respiratory function in HA surgery. Thus, the lateral position may be associated with beneficial effects on gas exchange.

Investigation of the process intergrowth of bone tissue into the hole in titanium implants (Experimental research)

INTRODUCTION

Despite the use of modern implants, complications such as nonunion and avascular necrosis of the femoral head are observed in femoral neck fractures (FNF). We have created a new perforated I-beam implant for FNF osteosynthesis and developed a new osteosynthesis philosophy based not only on the mechanical and biomechanical interaction of the bone-implant system, but also on the interaction of the biological properties of the bone and the implant. The purpose of the work is to study the interaction of the biological process of the bone - its regeneration (germination) of bone tissue into the holes of the implant.

MATERIALS AND METHODS

The experiment was carried out on fourteen Chinchilla rabbits in accordance with all international standards. A perforated implant specially made of titanium (ChM, Poland) was surgically implanted into the proximal femur. The implant measurements were as follows: length - 6 mm, width - 3 mm, thickness - 2 mm, 2 holes with a diameter of 2 mm. The 14 rabbits were divided into 7 groups. After 1, 2, 3, 4, 5, 10 and 12 weeks the animals were withdrawn from the experiment according to the standard rules in sequential order. The preparations were placed in a formalin solution and sent to the pathomorphology laboratory (CITO, Russia) for histological studies.

RESULTS

Weekly histopathological studies revealed a gradual transition from the organization of a hematoma to the formation of mature bone tissue in the holes of the implants. The titanium implant is bioinert and did not cause any visible reactions from the bone tissue. Simultaneous integration of vascular proliferation and newly formed bone tissue into the implant holes were revealed. On 10-12-week preparations, the formation of trabecular structures of mature bone tissue was revealed in the holes of the implants and elements of adipose and bone marrow tissue were observed. Macroscopic examination of 4-5-week preparations showed almost complete filling of the holes with bone tissue. On 10-12-week preparations, the bone tissue in the holes of the implants did not differ from the bone tissue surrounding the implant. The processes of formation of mature bone tissue in the holes of the implants were similar to the processes of physiological bone healing (regeneration) at the fracture site.

CONCLUSIONS

The obtained results show the following: 1.The titanium implant is bioinert and does not cause any visible reactions from the bone tissue; 2. There is a gradual process of formation of new vessels, and then the formation of new bone tissue in the holes of the implant instead of the one damaged during implantation. Thus, the results of this experiment indirectly confirm our assumption that a perforated implant for FNF osteosynthesis will participate not only in the mechanical and biomechanical interaction of the bone-implant system, but will also include the 3rd element in this system - the biological properties of the bone itself. We assume that these properties of the new implant will increase blood flow in the femoral neck and partially replenish the volume of bone tissue destroyed during osteosynthesis which does not occur with FNF osteosynthesis by any of the known implants.

The efficacy of dynamic compression locking system vs. dynamic hip screw in the treatment of femoral neck fractures: a comparative study

Background

There is still a lack of consensus on which internal fixation method can better maintain the stability of femoral neck fractures (FNF), promote fracture healing, and reduce postoperative complications such as femoral head necrosis and nonunion. Therefore, the purpose of this study was to evaluate the clinical efficacy of the novel dynamic compression locking system (DCLS) versus dynamic hip screw (DHS) in the treatment of FNF.

Methods

Fifty cases of FNF from July 2018 to February 2020 were retrospectively analyzed. According to different treatment methods, they were divided into DCLS group (26 cases) and DHS group (24 cases). Baseline data, intraoperative and postoperative clinical data, reoperation rate, and Harris score were collected to evaluate the clinical efficacy.

Results

All patients were followed up for 24 months. All “fractures” were caused by fall. The baseline data of the two groups were comparable (P > 0.05). There weren’t significant differences in the length of hospital stay and mobility after two years postoperatively between the two groups (P > 0.05). The operation time, blood loss, incision length, fluoroscopy times and the degree of femoral neck shortening after two years postoperatively in the DCLS group were significantly less than those in the DHS group (all P < 0.05). Harris score after two years postoperatively in the DCLS group was significantly higher than that in the DHS group (P < 0.05). Although the reoperation rate in the DHS group was slightly higher than that in the DCLS group, it wasn’t statistical significance (P > 0.05).

Conclusions

Compared with DHS, DCLS in the treatment of FNF had less surgical trauma, shorter incision length, shorter operation time, lower radiation dose and higher Harris scores. Although the reoperation rate in the DHS group was slightly higher than that in the DCLS group, it wasn’t statistical difference. Further research is needed.

Femoral neck system reduces surgical time and complications in adults with femoral neck fractures: A systematic review and meta-analysis

PURPOSE

Femoral neck fractures (FNF) in adults are conventionally managed with surgical options. This paper is aimed to assess the safety, and functional outcomes of the novel Femoral neck system (FNS) for FNF treatment in adult population.

METHODS

An organized quest of four literature databases (PubMed, Scopus, Web of Science, and Cochrane Library) was performed on March 1, 2022 using the term "femoral neck system". Fixed or random-effect meta-analysis was used to analyse the outcome measures after selecting relevant studies and assessing their quality. Heterogeneity was considered when calculating pooled effect sizes and 95% confidence ranges.

RESULTS

On comparing FNS with cannulated cancellous screws (CCS) or other methods, in a total of 762 patients (351 FNS and 411 CCS) in the 11 comparative studies considered for meta-analysis, blood loss was pointedly higher overall in the FNS group, mean difference 115.77 ml; 95% CI 3.11 ml, 28.42 ml; test of overall effect: z = 1.68, p = 0.09); with considerable heterogeneity. However, in the FNS group the operative time was substantially lower (Mean difference -7.91 min; 95% CI -15.01, -0.80; test of overall effect: z = 2.18, p = 0.03, with marked heterogeneity). Moreover, complications such as infections, non-union, osteonecrosis, implant cut-out were significantly lower in the FNS group with a Mantel Haenszel Odds ratio of 0.20 (95% CI 0.12, 0.34: Z = 6.01, p < 0.0001).

CONCLUSION

Keeping in mind the heterogenicity of the studies, -management of adult patients with FNF with FNS can provide results comparable to traditional fixation methods with significantly lower rate of complications.