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.

Bilateral Femoral Neck Pseudarthrosis in an Adolescent Girl With Congenital Spondyloepiphyseal Dysplasia. The Treatment Journey: A Case Report.

CASE: We describe the surgical management of a girl with dwarfism and congenital spondyloepiphyseal dysplasia, who presented in adolescence with coxa vara and bilateral pseudarthrosis between the femoral neck and the diaphysis, with asymmetric distal migration at both sites and leg length discrepancy. The patient at 16 years underwent valgus osteotomy in situ and femoral neck fixation in the left hip. The right hip was operated 19 months later. CONCLUSION: Hip dysplasia is common in spondyloepiphyseal dysplasia, but a debilitating nontraumatic bilateral pseudarthrosis at the base of the femoral neck has not been previously reported. Valgus corrective osteotomies of the femur in situ led to union and allowed the patient to walk.

Application direct anterior approach in pediatric femoral head and neck lesions.

BACKGROUND: Femoral neck is one of the high-risk areas for benign tumors and tumor-like lesions. Small range of lesions may also lead to pathological fracture, femoral head necrosis and other serious problems. PURPOSE: To investigate a new minimally invasive surgical approach to resect femoral head and neck lesions in children. PATIENTS AND METHODS: Retrospective study of 20 patients with femoral neck and femoral head lesions from February 2019 to March 2023 in our hospital. Among them, 14 were boys and 6 were girls, 17 were femoral neck lesions and 3 were femoral head lesions. The age of the patients ranged from 3.2 to 12.6 years, with a mean of 7.1 years. The patients were divided into group A and group B according to different surgical approaches; group A used the Smith-Peterson approach, Watson-Jones approach or surgical dislocation approach and group B used the DAA. Intra-operatively, incision length, operative time and blood loss were recorded in both groups. Group A consisted of 1 femoral head lesion and 8 femoral neck lesions, including 5 cases of bone cyst and 4 cases of eosinophilic granuloma. Group B consisted of 2 femoral head lesion and 9 femoral neck lesions. A total of 11 patients with different types of disease were included in group B, including bone cysts (3 cases), aneurysmal bone cysts (1 case), eosinophilic granulomas (6 cases), Kaposi's sarcoma (1 case). RESULTS: The two groups of patients differed in terms of incision length (P < 0.05), operative blood loss (P < 0.05) and operative time (P < 0.05). At 6-48 months post-operatively, there were no significant differences in function and all patients had good hip function. CONCLUSION: The direct anterior approach is effective for resection of paediatric femoral head and neck lesions. It provides clear exposure of the surgical site, minimal trauma and does not compromise the integrity of the anterior musculature. LEVEL OF EVIDENCE: III.

Sex-based differences in neck selectivity in total hip arthroplasty using a modular femoral neck system.

BACKGROUND: Dislocation is a major complication of total hip arthroplasty (THA). The modular femoral neck system provides practical advantages by allowing adjustment of neck version and length in the presence of intraoperative instability. Anatomical studies have identified morphological differences in the hip joint between men and women. Despite sex-based differences in hip morphology, it remains unclear whether such differences affect neck selectivity in THA using a modular neck system and whether this approach achieves anatomical reconstruction, thereby reducing complications such as dislocation. This study aimed to investigate gender differences in neck selectivity in THA with the modular neck system and assess the clinical impact of the modular neck system. METHODS: A total of 163 THAs using a modular neck system were included in this study. Data on the type of modular neck and intraoperative range of motion (ROM) were retrieved from patient records. Pre- and post-operative leg length differences (LLD) were examined as part of the radiographic assessment. Dislocation was investigated as a postoperative complication. RESULTS: Neck selectivity did not significantly differ between men and women. The comparison of pre- and post-operative LLD revealed a tendency for varus necks to improve LLD more than version-controlled necks. Furthermore, no significant correlation was found between intraoperative ROM and neck selectivity, or postoperative dislocation and neck selectivity. CONCLUSIONS: This study on THA with a modular neck system provided valuable insights into sex-based differences in neck selectivity and highlighted the potential benefits of the modular neck system in addressing LLD and preventing postoperative dislocation.

Computer-Assisted Arthroscopic Cam Resection.

Determining the appropriate femoral cam resection during hip arthroscopy for femoroacetabular impingement syndrome is both critical for the patient and challenging for the surgeon. Incomplete bone resection is a leading cause of failed hip arthroscopy, whereas over-resection may increase the risk of femoral neck fracture. The alpha angle is a validated 2-dimensional radiographic measurement used to both diagnose femoroacetabular impingement syndrome preoperatively and to determine resection adequacy postoperatively. Computer-assisted intraoperative guidance systems enhance the accuracy of femoral cam resection, although a preoperative 3-dimensional computed tomography scan may be required. Other systems, such as the HipCheck software (Stryker, Kalamazoo, MI), have been developed to provide intraoperative guidance with live feedback using simultaneous alpha angle measurements overlayed on fluoroscopic images without the requirement for routine preoperative computed tomography. Via intraoperative touchscreen navigation, the surgeon identifies the midpoint of the femoral neck and femoral head. A commercial software program provides real-time alpha angle measurements, as well as enhanced visualization of the femoral cam deformity with an adjustable resection curve. Before the surgeon performs the cam resection, the software provides a template for appropriate resection depth in 6 positions of the hip. Upon completion of the femoral cam resection, the hip is again assessed in the same 6 positions and the alpha angle is assessed to ensure a complete resection.

Stable fixation of an ultra-short femoral neck-preserving hip prosthesis: a 5-year RSA, DXA, and clinical prospective outcome study of 48 patients.

BACKGROUND AND PURPOSE: We previously showed promising primary stability and preservation of bone stock with the ultra-short neck-loading hip implant in total hip arthroplasty (THA). The aim of this study was to evaluate clinical outcome, implant stability, and bone mineral density (BMD). METHODS: 50 patients were treated with the ultra-short neck Primoris hip implant at baseline and 48 were available for evaluation at 5-year follow-up. 5 different patient-reported outcome measures (PROMs) including hip-specific scores, disease-specific and generic quality of life outcome measures, and an activity score were used. Furthermore, implant stability using radiostereometric analysis (RSA) and assessment of periprosthetic BMD using dual-energy X-ray absorptiometry (DXA) were applied. RESULTS: By 1-year follow-up, all PROMs showed improvements and remained high at 5-year follow-up. After initial distal translation (subsidence) and negative rotation around the z-axis (varus tilt) the implant showed stable fixation at 5-year follow-up with no further migration beyond 12 months. In the regions of interest (ROI) 3 and 4, BMD remained stable. In ROI 2, further bone loss of 12% was found at 5-year follow-up. CONCLUSION: Clinical outcome including PROMs was satisfying throughout the 5-year follow-up period. The hip implant remains stable with both bone preservation and loss 5 years after surgery.

Biomechanical Research of Three Parallel Cannulated Compression Screws in Oblique Triangle Configuration for Fixation of Femoral Neck Unstable Fractures.

OBJECTIVE: Surgical treatment with internal fixation, specifically percutaneous fixation with three cannulated compression screws (CCSs), is the preferred choice for young and middle-aged patients. The mechanical advantage of the optimal spatial configuration with three screws provides maximum dispersion and cortical support. We suspect that the spatial proportion of the oblique triangle configuration (OTC) in the cross-section of the femoral neck isthmus (FNI) may significantly improve shear and fatigue resistance of the fixed structure, thereby stabilizing the internal fixation system in femoral neck fracture (FNF). This study aims to explore the mechanical features of OTC and provide a mechanical basis for its clinical application. METHODS: Twenty Sawbone femurs were prepared as Pauwels type III FNF models and divided equally into two fixation groups: OTC and inverted equilateral triangle configuration (IETC). Three 7.3 mm diameter cannulated compression screws (CCSs) were used for fixation. The specimens of FNF after screw internal fixation were subjected to static loading and cyclic loading tests, respectively, with five specimens for each test. Axial stiffness, 5 mm failure load, ultimate load, shear displacement, and frontal rotational angle of two fragments were evaluated. In the cyclic loading test, the load sizes were 700 N, 1400 N, and 2100 N, respectively, and the fracture end displacement was recorded. Results were presented as means ± SD. Data with normal distributions were compared by the Student's t test. RESULTS: In the static loading test, the axial stiffness, ultimate load, shear displacement, and frontal rotational angle of two fragments were (738.64 vs. 620.74) N/mm, (2957.61 vs. 2643.06) N, (4.67 vs. 5.39) mm, and (4.01 vs. 5.52)° (p < 0.05), respectively. Comparison between the femoral head displacement after 10,000 cycles of 700N cyclic loading and total displacement after 20,000 cycles of 700-1400N cyclic loading showed the OTC group was less than the IETC group (p < 0.05). A comparison of femoral head displacement after 10,000 cycles of 1400N and 2100N cycles and total displacement after 30,000 cycles of 700-2100N cycles showed the OTC group was less than another group, but the difference was not significant (p > 0.05). CONCLUSION: When three CCSs are inserted in parallel to fix FNF, the OTC of three screws has obvious biomechanical advantages, especially in shear resistance and early postoperative weight-bearing, which provides a mechanical basis for clinical selection of ideal spatial configuration for unstable FNF.

Infantile Myofibromatosis of the Femoral Neck: A Case Report.

CASE: A 15-month-old boy who was being followed for developmental dysplasia of the hip because of breech presentation was discovered to have a solitary infantile myofibroma in the left femoral neck. The patient was avoiding weight-bearing on the affected extremity; thus, stabilization of the femoral neck was performed using a proximal femur locking plate. Postoperatively, he achieved all gross motor developmental milestones. CONCLUSION: This report is the first to describe a solitary infantile myofibroma in the femoral neck and demonstrates the utility of operative stabilization of these lesions.

La configuración de los tornillos en la osteosíntesis de las fracturas del cuello femoral no influye en los resultados funcionales ni mecánicos / The configuration of the screws in the osteosynthesis of fractures of the femoral neck does not influence the functional or mechanical outcomes

Antecedentes y objetivo: La síntesis con tornillos canulados es uno de los métodos aceptados en las fracturas de cuello femoral, aunque su óptima disposición es un tema en continuo debate. El objetivo principal fue comparar los resultados del paciente con fractura de cuello de fémur fijada con tres tornillos en configuración triangular y en triángulo invertido en el plano frontal. Materiales y métodos: Estudio retrospectivo y comparativo de 53 pacientes con fractura de cuello femoral intervenidos entre 2015 y 2022 mediante fijación con tres tornillos canulados: 22 conformados en triángulo (grupo triángulo) y 31 en triángulo invertido (grupo triángulo invertido). Se evaluó la funcionalidad mediante la escala modificada de Merlé d’Aubigné, la capacidad para la deambulación con la escala de Koval, así como las complicaciones postoperatorias. Resultados: En la escala de Merlé d’Aubigné la puntuación media fue de 16,7 en el grupo triángulo y de 16,1 en el grupo triángulo invertido (p=0,259). En la escala de Koval se observó una disminución significativa, pasando de 1,6 de media preoperatoria a 2,2 tras la cirugía (p=0,000), no hallando diferencias entre grupos. Hubo seis complicaciones postoperatorias en el grupo triángulo y tres en el grupo triángulo invertido (p=0,140). Conclusión: La configuración de los tornillos en el cuello femoral, tanto en forma de triángulo como en triángulo invertido, no influyó en los resultados funcionales ni mecánicos de los pacientes con fractura de cuello de fémur fijada mediante tres tornillos canulados.(AU)

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.(AU)

[Translated article] The configuration of the screws in the osteosynthesis of fractures of the femoral neck does not influence the functional or mechanical outcomes / La configuración de los tornillos en la osteosíntesis de las fracturas del cuello femoral no influye en los resultados funcionales ni mecánicos

Antecedentes y objetivo: La síntesis con tornillos canulados es uno de los métodos aceptados en las fracturas de cuello femoral, aunque su óptima disposición es un tema en continuo debate. El objetivo principal fue comparar los resultados del paciente con fractura de cuello de fémur fijada con tres tornillos en configuración triangular y en triángulo invertido en el plano frontal. Materiales y métodos: Estudio retrospectivo y comparativo de 53 pacientes con fractura de cuello femoral intervenidos entre 2015 y 2022 mediante fijación con tres tornillos canulados: 22 conformados en triángulo (grupo triángulo) y 31 en triángulo invertido (grupo triángulo invertido). Se evaluó la funcionalidad mediante la escala modificada de Merlé d’Aubigné, la capacidad para la deambulación con la escala de Koval, así como las complicaciones postoperatorias. Resultados: En la escala de Merlé d’Aubigné la puntuación media fue de 16,7 en el grupo triángulo y de 16,1 en el grupo triángulo invertido (p=0,259). En la escala de Koval se observó una disminución significativa, pasando de 1,6 de media preoperatoria a 2,2 tras la cirugía (p=0,000), no hallando diferencias entre grupos. Hubo seis complicaciones postoperatorias en el grupo triángulo y tres en el grupo triángulo invertido (p=0,140). Conclusión: La configuración de los tornillos en el cuello femoral, tanto en forma de triángulo como en triángulo invertido, no influyó en los resultados funcionales ni mecánicos de los pacientes con fractura de cuello de fémur fijada mediante tres tornillos canulados.(AU)

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.(AU)

Short versus conventional straight stem in uncemented total hip arthroplasty: functional outcomes up to 5 years and survival up to 12 years: secondary results of a randomized controlled trial.

BACKGROUND AND PURPOSE: To date, the mid- and long-term outcomes of the Collum Femoris Preserving (CFP) stem compared with conventional straight stems are unknown. We aimed to compare physical function at a 5-year follow-up and implant survival at an average of 10-year follow-up in an randomized controlled trial (RCT). METHODS: This is a secondary report of a double-blinded RCT in 2 hospitals. Patients aged 18-70 years with hip osteoarthritis undergoing an uncemented primary THA were randomized to a CFP or a Zweymüller stem. Patient-reported outcomes, clinical tests, and radiographs were collected at baseline, 2, 3, 4, and 5 years postoperatively. Primary outcome was the Hip disability and Osteoarthritis Outcome Score (HOOS) function in activities of daily living (ADL) subscale. Secondary outcomes were other patient-reported outcomes, clinical tests, adverse events, and implant survival. Kaplan-Meier and competing risk survival analyses were performed with data from the Dutch Arthroplasty Registry. RESULTS: We included 150 patients. Mean difference between groups on the HOOS ADL subscale at 5 years was -0.07 (95% confidence interval -5.1 to 4.9). Overall survival was 92% for the CFP and 96% for the Zweymüller stem. No significant difference was found. CONCLUSION: No significant differences were found in physical function at 5-year and implant survival at 10-year follow-up between the CFP and Zweymüller stems. When taking cup revisions into account, the CFP group showed clinically inferior survival.

Association of Relative Skeletal Immaturity of the Triradiate Cartilage with Increased Proximal Femoral Deformity in Prophylactic Fixation for Slipped Capital Femoral Epiphysis: A Radiographic Study.

INTRODUCTION: The purpose of this study was to describe proximal femoral deformity after contralateral hip prophylactic fixation of slipped capital femoral epiphysis (SCFE) in patients and the association of relative skeletal immaturity with this deformity. METHODS: A retrospective review of patients presenting with a SCFE was conducted from 2009 to 2015. Inclusion criteria were (1) radiographic evidence of a unilateral SCFE treated with in situ fixation, (2) contralateral prophylactic fixation of an unslipped hip, and (3) at least 3 years of follow-up. Measurements were made on radiographs and included greater trochanter height relative to the center of the femoral head, femoral head-neck offset, and femoral neck length. Skeletal maturity was evaluated by assessing the status of the proximal femoral physis and triradiate cartilage (TRC) of the hip, in addition to the length of time to closure of these physes. Values were compared from initial presentation to final follow-up. Statistical analysis included descriptive statistics and linear regression. RESULTS: Twenty-seven patients were included. Bivariable linear regression demonstrated that an increased relative trochanteric overgrowth was associated with TRC width (ß = 3.048, R = 0.585, P = 0.001) and an open TRC (ß = -11.400, R = 0.227, P = 0.012). Time to proximal femoral physis closure (ß = 1.963, R = 0.444, P = 0.020) and TRC closure (ß = 1.983, R = 0.486, P = 0.010) were predictive of increased deformity. In addition, multivariable elimination linear regression demonstrated that TRC width (ß = 3.048, R = 0.585, P = 0.001) was predictive of an increased relative trochanteric overgrowth. DISCUSSION: Patients with an open TRC and increased TRC width are associated with increased relative trochanteric overgrowth when undergoing prophylactic fixation for a unilateral SCFE. Increased caution should be exercised when considering contralateral hip prophylactic fixation in skeletally immature patients presenting with a unilateral SCFE. LEVEL OF EVIDENCE: Level IV, case series.

Calcar-guided short-stem total hip arthroplasty in fractures of the femoral neck: a prospective observational study of 68 hips.

INTRODUCTION: The indications for cementless short-stem total hip arthroplasty (THA) have been expanded due to encouraging results. However, no evidence in cases of femoral neck fractures (FNFs) is available. We aimed to prospectively obtain data on the safety and the clinical outcomes of a cementless calcar-guided short stem in patients with FNFs. MATERIALS AND METHODS: We conducted a prospective observational study of 68 patients diagnosed with FNFs who underwent short-stem THA between 2016 and 2019 with a calcar-guided stem. Complications during follow-up leading to revision were documented, and patient reported outcome measurements recorded. Stem migration was analyzed using the Einzel-Bild-Röntgen-Analysis Femoral Component Analysis software. RESULTS: The mean follow-up was 33.8 ± 14.8 months. The patient mortality at last follow-up was 10.6%. Two patients required stem revision, due to periprosthetic fracture and late aseptic loosening, respectively, corresponding to 96.2% stem survival. Survivorship for the endpoint of revision for any reason was 91.1% at 6 years. All revisions occurred in females. The mean Harris Hip Score at the last follow-up was 93.0 ± 8.9. The mean axial migration at last follow-up was 1.90 ± 1.81 mm. No significant influence on migration was found regarding gender, age, weight, and body mass index. CONCLUSIONS: The clinical and radiological findings were satisfying and most patients benefited from the minimally invasive procedure. However, as for conventional THA as well, implant survivorship and mortality were markedly worse compared to results regarding osteoarthritis. Especially in elderly female patients with FNF, cementless short-stem THA is a concern and a cemented THA should be the first choice.

An Imaging Assessment of the Femoral Neck-shaft Angle in Adult Bengali Bangladeshi Population.

Most orthopaedics implants were designed and manufactured based on data from the Western population whose skeletal dimensions are different from the Bengali Bangladeshi population. This study aims to determine the value of the femoral neck-shaft angle of the adult Bengali Bangladeshi population for adequate planning, preparation and pre-operative selection of orthopaedic implants for surgeries involving the femoral neck and stocking of orthopaedic implants. This was a cross-sectional analytical study which involved measuring the femoral neck-shaft angle (NSA) from the pelvic radiographs anterior-posterior view of adult patients reported "normal study" by the registered radiologist. This study was carried out in the Department of Anatomy, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh from March 2019 to February 2020. A total of 200 femoral neck-shaft angles were analyzed from 100 patients' radiographs comprising 50 males and 50 females. The average NSA of adult Bengali Bangladeshi is 128.74°±5.83° with a mean value of 128.68°±6.20° for the right and 128.81°±5.66° for the left. The mean value of NSA is 129.64°±5.90° and 127.85°±5.64° in adult males and females respectively. The femoral neck-shaft angle in adult Bengali Bangladeshi males was significantly higher than the females.

United States Experience With a Femoral Neck Retaining Total Hip Arthroplasty Stem: A Retrospective Study With Control Comparison From the Literature.

BACKGROUND: Femoral neck retaining prostheses have gained popularity in Europe, but the United States has not seen the same trends occurring. Previous reports demonstrate high survivorship for these implants, but to our knowledge, there are no reports examining US data. METHODS: After institutional review board approval, 824 primary total hip arthroplasties utilizing a femoral neck-retaining prosthesis were examined for femoral component survivorship rates. European studies were systematically reviewed to determine survivorship rates. The data were used to formulate a Kaplan-Meier survivorship curve and compare US data to that of the European studies. RESULTS: European studies demonstrated survivorship rates for all causes of 97.7 and 99.0% for aseptic loosening at an average of 6 years (range, 4.5 to 10). The current study demonstrated an all-cause 94% Kaplan-Meier survivorship estimate at 5 years and when aseptic loosening only was considered, survivorship increased to 99.4% at 5 years and 98.4% at 11 years. CONCLUSION: This femoral neck-retaining prosthesis demonstrated excellent survivorship that is comparable to the rates seen in European studies as well as the rates of standard and mid-stem prostheses in the United States.

Predicting Instability Risk Following Hemiarthroplasty for Femoral Neck Hip Fractures in Geriatric Patients.

BACKGROUND: Although a rare complication, dislocation following hemiarthroplasty (HA) for a femoral neck hip fracture is associated with increased mortality, readmission, and possible revision surgery. To date many of the specific risk factors have been difficult to demonstrate. Patient factors, surgical factors, as well as morphological factors need to be assessed. Therefore, the purpose of this study was to elucidate the risk factors for dislocation of HA following femoral neck hip fractures in the geriatric population. METHODS: This was a retrospective review of 270 patients who had hip fractures. Medical records between the years 2016 and 2022 informed binomial regression predictive models. The discriminative ability of variables in the final model and acetabular anteversion to predict dislocation was assessed with area under the curve (AUC) estimates. RESULTS: Center edge angle (odds ratio 1.23), abduction angle (odds ratio 1.17), and depth width ratio (2.96e-11) were significant predictors of dislocation (P = .003, .028, and <.001, respectively). Center edge angle and depth width ratio (<44.1 ° and .298), respectively, were cut scores for risk. Dementia had a high discriminative of ability, as did men (AUC = 0.617, 0.558, respectively). Acetabular anteversion was not predictive of dislocation (P = .259) and theorized anteversion safe zones had poor discriminative ability with AUCs of 0.510 and 0.503, respectively. CONCLUSIONS: Morphological factors related to hip dysplasia and a shallow acetabulum, which can be assessed with a radiograph alone, were found to be predictors of instability following HA in the elderly. Hemiarthroplasty implant design and manufacturer, and also acetabular version did not contribute to instability risk.

The Duration of Hardware Retention After Radiologic Union of Surgically Treated Femoral Neck Fractures in Children May Predict the Aggravation or Occurrence of Avascular Necrosis of the Femoral Head or Neck After Hardware Removal.

BACKGROUND: The incidence of aggravation or occurrence of avascular necrosis (AVN) following hardware removal in surgically treated pediatric femoral neck fractures who achieved radiologic consolidation is unknown. This study aimed to investigate the risk factors for this complication. METHODS: Seventy-one pediatric (mean age: 9.8±3.9 y) were retrospectively analyzed. Risk factors (age, sex, laterality, severity of initial displacement, type of fracture, time from trauma to reduction, reduction and fixation method, quality of reduction, time required to achieve radiologic union, duration of hardware retention, presence of AVN before hardware removal and follow-up time) were recorded. The severity of AVN was assessed based on radiographs with Ratliff's classification. RESULTS: Following hardware removal, the aggravation/occurrence of AVN was detected in 11 hips (15.5%). Among the 5 hips (7%) with aggravation of AVN, 1 (1.4%) with type II AVN and 3 (4.2%) with type III AVN exhibited aggravation of type I AVN, while the remaining hip (1.4%; type I) showed enlargement of the involved AVN area. Six hips (8.5%) developed AVN following hardware removal: 2 (2.8%) were classified as type I and 4 (5.6%) as type III. Receiver operating characteristic curve analysis indicated that hardware retention >7 months after union is associated with a decreased rate of aggravation or occurrence of AVN of the femoral neck or head following hardware removal. CONCLUSIONS: The incidence of aggravation or occurrence of AVN following hardware removal in surgically treated pediatric femoral neck fractures is 15.5%; hardware retention >7 months after radiologic union may reduce the risk of aggravation or occurrence of AVN of the femoral neck or head postimplant removal. LEVEL OF EVIDENCE: Level III.

Femoral Neck Preservation and Diaphyseal Invasion Comparing a Calcar-Metaphyseal Short Stem with its Homonymous Standard Femoral Stem. A Radiographic Study.

BACKGROUND: We aim to compare the preoperative planning radiographs of 50 patients in whom both a short stem and its homonymous standard version were programmed, focusing on the preservation of the neck and the invasion of the femoral shaft. The secondary objective was to evaluate the 50 preoperative radiographs with the 50 postoperative radiographs in which the short stem was implanted, measuring the real invasion of the diaphysis and the real preservation of the femoral neck. MATERIAL AND METHODS: We measured cut level at the femoral neck and diaphyseal invasion in 50 preoperative x-rays where an Alteon Neck Preserving Stem (ANPS) was templated and we compared it with 50 preoperative x-rays where an Alteon Taper Wedge Stem (ATWS) was templated. After surgery, we compared both parameters previously measured in the preoperative x-rays with the 50 postoperative radiographs where the short stem was implanted obtaining the real bone preservation at the femoral neck and the real diaphyseal invasion length. RESULTS: For templating comparison, mean bone preservation at the femoral neck was 14.87mm (SD 3.64) for the ANPS group and 9.94mm (SD 8.39) for the ATWS group (p <0.001). The mean diaphyseal bone invasion was 47.21mm (SD 5.89) and 76.77mm (SD 8.39) for ANPS and ATWS respectively (p <0.001). After surgery, the mean postoperative bone preservation at the femoral neck was 15.08mm (SD 3.1) with a mean of 0.17mm (SD 0.51) more preservation in the preoperative group. CONCLUSION: 1. ANPS allow bone preservation with limited diaphyseal invasion when compared with his homonymous ATWS in the preoperative templates. 2. ANPS showed a good correlation between preoperative radiographs and real bone preservation of the femoral neck and invasion of the femoral shaft.

Femoral neck fracture after femoral head necrosis: a case report and review of the literature.

INTRODUCTION: Pathological fractures of the femoral neck caused by necrosis of the femoral head are extremely rare. Here, we report a rare case of bilateral femoral head osteonecrosis extending to the femoral neck, with bilateral pathological fractures of the femoral neck occurring within a short period of time. CASE REPORT: A 65-year-old male with a 25-year history of daily consumption of 750 ml of liquor, presented with right hip pain after labor for 1 month. He subsequently sustained a right femoral neck fracture without trauma and underwent a right total hip arthroplasty. Two months later, he suffered a non-traumatic left femoral neck fracture and underwent a left total hip arthroplasty. Histopathological examination revealed osteonecrosis of the femoral head and neck, along with the presence of osteoclasts and granulomatous inflammation. Bone mineral density testing also showed osteoporosis. The bilateral femoral neck fractures were ruled out to be caused by any other pathological factors. DISCUSSION: This is the first report of pathological fractures of the bilateral femoral neck caused by femoral head necrosis. During the literature review process, we found that this case conforms to the histological characteristics of rapidly destructive hip disease and analyzed the etiology of femoral head necrosis and the pathogenesis of femoral neck fractures.

A neck-sparing short stem shows significantly lower blood loss in total hip arthroplasty compared to a neck-resecting short stem.

Short stems are associated with a significantly lower blood loss (BL) compared to straight stems in total hip arthroplasty (THA). Different types of stems differ in design, fixation and level of femoral neck osteotomy. Therefore, we sought to evaluate the difference regarding the perioperative BL between two short stems with different designs in direct anterior approach (DAA). A total of 187 THA performed by a single surgeon were analysed. 107 patients received a neck-resecting (Group A) and 80 patients a neck-sparing short stem (Group B). Blood counts of the day before surgery and of two days after surgery were evaluated. Total blood volume and BL were calculated. Additionally, duration of surgery was analysed. The perioperative BL was significantly lower in Group B (451.4 ± 188.4 ml) compared to Group A (546.6 ± 232.7 ml; p = 0.002). The postoperative haematocrit (31.6 ± 3.7% vs. 30.4 ± 4.4%; p = 0.049) and haemoglobin-level (11.0 ± 1.3 g/dL vs. 10.4 ± 1.5 g/dL; p = 0.002) were significantly higher in Group B. Duration of surgery was significantly shorter in Group B (62.0 ± 11.4 min vs. 72.6 ± 21.8 min; p < 0.001). The use of a neck-sparing short stem leads to a significantly decreased BL compared to a neck-resecting short stem in DAA THA. A less extensively conducted capsular release necessary for optimal femoral exposition might lead to a lower perioperative BL and shorter durations of surgery.