Nonanatomical reduction of femoral neck fractures in young patients treated with femoral neck system: a retrospective cohort study.

PURPOSE: Negative buttress reduction should be avoided in the treatment of femoral neck fractures (FNFs) using conventional fixation. As the femoral neck system (FNS) has been recently developed and utilized widely to treat FNFs, the association of reduction quality with postoperative complications and clinical function has not been clarified. The purpose of this study was to evaluate the clinical effect of nonanatomical reduction in young patients with FNFs treated with FNS. METHODS: This multicenter, retrospective cohort study included 58 patients with FNFs treated with FNS between September 2019 and December 2021. According to the reduction quality immediately following surgery, patients were classified into positive, anatomical, and negative buttress reduction groups. Postoperative complications were assessed with 12 months of follow-up. The logistic regression model was used to identify risk factors for postoperative complications. The postoperative hip function was assessed using the Harris hip scores (HHS) system. RESULTS: At a follow-up of 12 months, a total of eight patients (8/58, 13.8%) had postoperative complications in three groups. Compared with the anatomical reduction group, negative buttress reduction was significantly associated with a higher complication rate (OR = 2.99, 95%CI 1.10-8.10, P = 0.03). No significant associations were found between positive buttress reduction and the incidence of postoperative complications (OR = 1.21, 95%CI 0.35-4.14, P = 0.76). The difference was not statistically significant in Harris hip scores. CONCLUSION: Negative buttress reduction should be avoided in young patients with FNFs treated with FNS.

Long-Term Outcome of Valgus Osteotomy and Fixation with Double Angled Dynamic Hip Screw for Nonunion Fracture of the Neck of the Femur in Young Adults / Desfecho a longo prazo da osteotomia valgizante e fixação com parafuso dinâmico de quadril de ângulo duplo de fratura não consolidada do colo femoral em adultos jovens

Abstract Objective To evaluate the long-term results of valgus intertrochanteric osteotomy fixed with double angled dynamic hip screw for nonunion fracture of the neck of the femur in young adults. This implant allows more freedom of fixation in the sagittal plane. Very few studies have evaluated the long-term outcome for treatment of nonunion in fractures of the neck of the femur. Methods This is a prospective interventional study that included 20 patients with nonunion of the fracture of the neck of the femur aged < 60 years old without avascular necrosis of the head and significant resorption of the neck of the femur. A lateral closing wedge osteotomy was performed just above the lesser trochanter after inserting the Richard screw across the nonunion site, and it was fixed with a double-angle 120° barrel plate. The outcome was evaluated using union rate and the Harris Hip Score for functional outcome. Results The average postoperative decrease in the Pauwels angle was of 28.9°. A total of 80% of the cases progressed to union within a mean duration of 7.53 months. The mean Harris Hip Score at the final follow-up was 86.45. Conclusion Valgus intertrochanteric osteotomy and fixation with a double angled dynamic hip screw is a reliable and effective method for preservation of head and promoting union in an ununited fractured neck of the femur in young patients.

Resumo Objetivo Avaliar os resultados a longo prazo da osteotomia intertrocantérica valgizante, fixada com parafuso dinâmico de quadril (DHS, na sigla em inglês) de ângulo duplo, em fraturas não consolidadas do colo femoral em adultos jovens. Este implante permite uma liberdade maior de fixação no plano sagital. Muito poucos estudos avaliaram o desfecho do tratamento a longo prazo da fratura não consolidada do colo femoral. Métodos Trata-se de um estudo prospectivo de intervenção que incluiu 20 pacientes com fratura não consolidada do colo femoral com idade < 60 anos, sem necrose avascular da cabeça femoral e significativa reabsorção do colo femoral. Foi realizada uma osteotomia em cunha de fechamento lateral logo acima do trocânter menor após a inserção do parafuso tipo Richard no sítio do retardo da consolidação óssea, sendo fixada com uma placa cilíndrica de ângulo duplo de 120°. O resultado foi avaliado com o uso da taxa de consolidação e da escala Harris Hip Score quanto ao desfecho funcional. Resultados Foi obtida uma redução pós-operatória média de 28,9° do ângulo de Pauwels. Os casos que evoluíram para a consolidação alcançaram 80%, em um período médio de 7,53 meses. A média da escala Harris Hip Score foi de 86,45 no acompanhamento final. Conclusão A osteotomia intertrocantérica valgizante e a fixação com DHS de ângulo duplo é um método confiável e eficaz para a preservação da cabeça do fêmur, promovendo a consolidação de uma fratura não consolidada do colo femoral em pacientes jovens.

Ipsilateral femoral neck and shaft fracture in children: Two case reports.

RATIONALE: Pediatric femoral shaft combined with ipsilateral femoral neck fractures are very rare but challenging injuries fraught with the development of avascular necrosis, coxa vara, and leg length discrepancy. Majority of the previous reports indicated the neck femur fracture was fixed with cannulated screws or/and pins, femoral shaft fracture was stabilized with a plate and screws. However, we used cannulated screws combined with elastic stable intramedullary nails to minimally invasive procedures treat this type of injury and achieved good follow-up results. PATIENT CONCERNS: A 7-year-old boy (Case 1) was hospitalized due to a traffic accident resulting in swelling and deformity of the right thigh accompanied by limited mobility of hip and knee. A 5-year-old male child (Case 2) presented with pain and swelling in the bilateral lower limb after fall from approximately 12 feet. DIAGNOSES: Physical examination, X-ray film, and computed tomography were performed. Both patients were diagnosed with ipsilateral femoral neck and shaft fracture. INTERVENTIONS: The fractures were reduced closed by image-intensifier imaging. Two partially threaded cancellous screws were used to fix femoral neck fracture, and elastic intramedullary nails were performed to stable the femoral shaft fracture. Postoperatively, the patients were immobilized in a one-and-a-half hip spica cast for six weeks. The internal fixations were removed after one year. OUTCOMES: Case one was follow-up at 14 months and the other one was followed up for 3 years. And at the last follow-up showed a normal and painless hip function. No clinical complications were found during follow-up visit, including head penetration, implant failure, fracture nonunion, avascular necrosis and hip varus deformity. LESSONS: Clinician should carefully check and read relevant imaging data to avoid missed diagnosis. And the internal fixation method described in this paper may be more minimally invasive.

Fatigue fracture of an uncemented Zweymüller femoral stem at the neck-shoulder junction.

A fracture through the neck of the femoral stem in total hip arthroplasty is extremely rare. We report a neck fracture of a cementless Zweymüller stem, one of the most implanted stems worldwide. According to our knowledge, this is the first thorough case description of a neck fracture of a cementless Zweymüller stem. The case concerns a 53-year-old man, with a body weight of 103 kg and a body mass index of 31. We consider potential risk factors for a femoral stem fracture, such as patient-related factors, suboptimal implant positioning, surgical technique and implant characteristics.

A meta-analysis of fracture risk and bone mineral density in patients with systemic sclerosis.

INTRODUCTION: Osteoporosis and fractures are important public health issues that impose serious burdens on patients. Patients with systemic sclerosis (SSc) have low bone mineral density (BMD) and increased risk for fracture. We aimed to explore the association between SSc and BMD and fracture risk. METHODS: For this meta-analysis, we analyzed data from articles that reported mean differences in BMD or fracture risk between patients with SSc and controls. We undertook a systematic literature search of the PubMed, Web of Science, and Cochrane Library databases. The pooled weighted mean difference (WMD) was used to estimate the mean difference in BMD between patients with SSc and controls. Pooled odds ratios (ORs; with 95% confidence intervals [95% CIs]) were used to assess the association between SSc and fracture risk. RESULTS: Analysis of the results from 18 studies showed that patients with SSc had significantly lower BMD than controls in the following categories: whole body (WMD - 0.07, 95% CI - 0.1 to - 0.04, p < 0.00001), lumbar spine (WMD - 0.08, 95% CI - 0.11 to - 0.05, p < 0.00001), femoral neck (WMD: -0.28, 95% CI: -0.46 to -0.10, p=0.002), total hip (WMD - 0.10, 95% CI - 0.14 to - 0.06, p < 0.00001), and femoral trochanter (WMD - 0.06, 95% CI - 0.09 to - 0.03, p < 0.0001). Moreover, patients with SSc had an increased risk of vertebral fracture (OR 10.38, 95% CI 1.19 to 90.58, p = 0.03). We did not find a significant difference in the risk of osteoporotic fracture between patients with SSc and controls (OR = 2.24, 95% CI 0.58 to 8.59, p = 0.24). CONCLUSION: Patients with SSc have a significant reduction in bone mass, and these patients have an increased risk of vertebral fracture. The early monitoring of BMD in patients with SSc is recommended for the prevention of osteoporosis and fracture.Key points• SSc patients have a significant low BMD• SSc patients also have an increased risk of vertebral fracture.

Early mechanical complications following fixation of proximal femur fractures: From prevention to treatment.

Proximal femur fractures have significant functional repercussions in both older adults (sometimes life-threatening) and younger adults (socioeconomic). This study will review the early mechanical complications (EMC) associated with the fixation of femoral neck (FNF) and trochanteric (TF) fractures. What is the nature of these complications? They consist of incorrect fracture fixation, secondary displacement and/or fixation failure (FNF: 3-10%; TF: 5-7%), and more rarely, secondary fractures distal to the implant. What are the risk factors and how can they be controlled? They are related to the patient (osteoporosis), to the type of fracture (FNF: posterior comminution, magnitude of displacement, vertical fracture line, fracture of calcar/TF: comminution of calcar, lesser trochanter fracture, metaphyseal comminution, lateral cortex fracture, greater trochanter comminution), to the chosen treatment (FNF: triple screw fixation or screw-plate are preferable/TF: all implants suitable for simple fractures, cervicomedullary implants for complex fractures), and to the surgical technique (quality of reduction, implant positioning). How should they be treated? Early revision of internal fixation can be difficult and increases the infection risk. Inter- or subtrochanteric valgus osteotomy leads to satisfactory results but is difficult to carry out. Secondary arthroplasty, which is the preferred option in older adults, leads to good outcomes but is technically more difficult, and has a higher complication rate in EMC of trochanteric fractures. LEVEL OF EVIDENCE: V.

Nanohydroxyapatite Based Ceramic Carrier Promotes Bone Formation in a Femoral Neck Canal Defect in Osteoporotic Rats.

Hip fractures are among the most common types of fracture risks in old age osteoporotic patients that often end up with immobile disabilities. Weak bones due to loss of mineral content along with an increase in the porosity of the femur neck canal in osteoporosis reduce the mechanical properties of the bone and predispose the patients to fractures. In this study, we have used calcium sulfate/nanohydroxyapatite based nanocement (NC) as carrier of recombinant human bone morphogenetic protein-2 (BMP-2), zoledronate (ZA), and bone marrow mesenchymal stromal cells (MSCs) derived exosomes (EXO) to enhance bone formation and defect healing in a femur neck canal defect model in osteoporotic rats. A cylindrical defect in the femur neck canal with dimensions of 1 mm (diameter) × 8 mm (length) starting from the lateral cortex toward the apex of the femur head was developed. The defect was impacted using NC alone or functionalized as (a) NC + ZA (systemic), (b) NC + ZA (local), (c) NC + EXO + ZA, and (d) NC + BMP + ZA to evaluate bone formation by ex vivo micro-computed tomography (micro-CT) and histological analysis 16 weeks postsurgery. Moreover, the femurs (both defect and contralateral leg) were subjected to biomechanical analysis to assess the effect of treatments on compressive mechanical properties of the bones. The treatment groups (NC + ZA (L), NC + BMP + ZA, and NC + EXO + ZA) showed enhanced bone formation with complete healing of the defect. No differences in the mechanical properties of both the defect and contralateral across the leg were observed among the groups. However, a trend was observed where NC + BMP + ZA showed enhanced biomechanical strength in the defect leg. This suggests that NC could act as a potent carrier of bioactive molecules to reduce the risks of hip fractures in osteoporotic animals. This type of treatment can be given to patients who are at higher risk of osteoporosis mediated femur neck fracture as a preventive measure or for enhanced healing in already compromised situations. Moreover, this study provided a proof of concept regarding the use of exosomes in bone regeneration therapy, which might be used as a booster dose that will eventually reduce the dosage of BMP and hence circumvent the limitations associated with the use of BMP.

Spontaneous bilateral femoral neck fractures in a young male adult: a case report and literature review.

BACKGROUND: Simultaneous bilateral femoral neck fracture is a very rare condition, even in osteoporotic elderly individuals. We report an atypical case of a young male adult who developed simultaneous bilateral femoral neck fractures without previous trauma or overuse. CASE PRESENTATION: A 33-year-old man presented with discomfort in the bilateral groin, which had started 2 weeks previously. Bilateral femoral neck fractures were observed on a radiograph, and in addition, a fracture line was seen at the right subchondral region of the acetabulum using magnetic resonance imaging (MRI). Although the patient had no obvious risk factors associated with bone fragility, his bone mineral density measured using dual X-ray absorptiometry indicated severe osteoporosis (lumber spine: T score - 3.4 standard deviation [SD]; femoral neck: T score - 2.8 SD). Serum 25-hydroxyvitamin D level was deficient (19 ng/mL), which was considered to be partly due to non-sunlight exposure for 3 years owing to social withdrawal. Bilateral osteosynthesis was performed, considering his young age, although more than 2 weeks had passed since the onset of the fracture. Bone union and non-occurrence of osteonecrosis of the femoral head were confirmed via radiography and MRI 8 months after the surgery. CONCLUSIONS: Our case suggests that simultaneous non-traumatic bilateral femoral neck fractures can occur in healthy young men.

Periprosthetic fracture morphology of a femoral neck prosthesis: An in vitro study.

Femoral neck prostheses have been developed for the treatment of osteoarthritis in young and active patients. The concept combines a bone-conserving and minimal invasive technique with proximal load transferring by metaphyseal anchoring, which results in a more physiological loading pattern. However, little is known about the morphology of periprosthetic fractures. Thus, the aim of this study was to describe fracture patterns and to determine patient-specific factors favoring periprosthetic fracture. This study was performed as a biomechanical experimental study using 10 fresh frozen femora and 10 Silent-Hip femoral neck implants (DePuy International Ltd., Leeds, UK). In order to simulate physiological loading, a static muscle reconstruction (abductor muscles and iliotibial band) and a dynamic simulation of the gait cycle were applied. During biomechanical testing (50% and 100% of normal weight-bearing), three periprosthetic fractures with two different morphologies occurred. The first pattern corresponds to an abrupt breakaway. The second type was of spiral configuration extending to the diaphyseal region and emerging from an initial fissure. Specimen-specific factors favoring periprosthetic fracture were body mass index and varus angle of the implant. Periprosthetic fractures may extend to the subtrochanteric/diaphyseal region and may be of spiral configuration. According to the finding of this study, body mass index and varus/valgus position of the implant are important factors influencing the risk of periprosthetic fractures. Furthermore, partial weight-bearing as part of the postoperative regimen may be favorable.

The influence of ageing on the incidence and site of trauma femoral fractures: a cross-sectional analysis.

BACKGROUND: This study aimed to determine the influence of ageing on the incidence and site of femoral fractures in trauma patients, by taking the sex, body weight, and trauma mechanisms into account. METHODS: This retrospective study reviewed data from adult trauma patients aged ≥20 years who were admitted into a Level I trauma center, between January 1, 2009 and December 31, 2016. According to the femoral fracture locations, 3859 adult patients with 4011 fracture sites were grouped into five subgroups: proximal type A (n = 1359), proximal type B (n = 1487), proximal type C (n = 59), femoral shaft (n = 640), and distal femur (n = 466) groups. A multivariate logistic regression analysis was applied to identify independent effects of the univariate predictive variables on the occurrence of fracture at a specific site. A two-dimensional plot was presented visually with age and the propensity score accounts for the risk of a fracture at a specific femoral site. RESULTS: This analysis revealed that older age was an independent variable that could positively predict the occurrence of proximal type A (OR [95%CI]: 1.03 [1.03-1.04], p < 0.001) and B fractures (1.02 [1.01-1.02], p < 0.001), and negatively predict the occurrence of proximal type C (0.96 [0.94-0.98], p < 0.001), shaft (0.95 [0.95-0.96], p < 0.001), and distal fractures (0.98 [0.98-0.99], p < 0.001). DISCUSSION: Using the propensity scores which account for the risk of a fracture in a specific femoral site, this study revealed that the older patients were at a higher risk of developing proximal type A and type B fractures, while a lower risk of developing fractures in the shaft and distal femur. This incidence of fracture site can largely be explained by age-related factors, including a decrease in bone strength and falling being the most common mechanism of trauma in older patients. CONCLUSIONS: This study revealed a difference in the involvement of age in the incidence of femoral fracture sites in the trauma patients.

The trend of radiological severity of hip fractures over a 30 years period: a cohort study.

BACKGROUND: Despite advances in operative techniques and preoperative care, proximal femur fractures (PFF) still represent a great public health problem. Displacement and fracture stability have been assumed as important determinants of treatment modality and outcome in such fractures. Purpose of this study was to determine whether the radiological severity of PFF fractures has increased over time. METHODS: In a cohort study, the plain radiographs of all patients with PFF aged over 50 years who were admitted to Umeå University Hospital in 1981/82, 2002 and 2012 were recruited to examine the types of fractures. RESULTS: The ratio of undisplaced to displaced femoral neck (FN) fractures was 30 to 70% in 1981/82, 28 to 72% in 2002 and 25 to 75% in 2012. The ratio of stable to unstable intertrochanteric (IT) fractures was 64 to 36% in 1981/82, 68 to 32% in 2002 and 75 to 25% in 2012. The ratio of simple to comminute subtrochanteric fractures was 35 to 65% in 1981/82, 16 to 84% in 2002 and 12 to 88% in 2012. In both FN and IT fractures we found no statistical difference among these 3 study periods, p = 0.67 and p = 0.40. In subtrochanteric fractures we saw a tendency towards more comminute subtrochanteric fractures (1981/82 to 2012), p = 0.09. CONCLUSIONS: We found no significant increment in the radiological severity of FN and IT over a 30 years' period. However, there was tendency towards an increase in comminute subtrochanteric fractures.

Posterior Approach for a Cemented Hemiarthroplasty.

PURPOSE: Femoral neck fractures are common injuries with over 1 million occurring yearly. This video demonstrates a case of a displaced femoral neck fracture treated with a cemented hemiarthroplasty through a posterior approach. METHODS: Multiple approaches to the hip for arthroplasty have been described, each with advantages and disadvantages. Careful technique is critical to success. RESULTS: This presents a case of a displaced femoral neck fracture treated with a cemented hemiarthroplasty through a posterior approach. CONCLUSIONS: Displaced femoral neck fractures are common fractures. The posterior approach for cemented hemiarthroplasty is a safe, reproducible technique.

Biomechanical Evaluation of the Modified Cannulated Screws Fixation of Unstable Femoral Neck Fracture with Comminuted Posteromedial Cortex.

PURPOSE: To verify the biomechanical importance with respect to the integrity of posteromedial cortex of femoral neck fracture (FNF) and demonstrate whether the modified fixation of cannulated screws (CSs) could increase the biomechanical strength. METHODS: A total of 24 left artificial femurs were randomly divided into three groups. The osteotomy was made in the center of the femoral neck at a 20° angle to the shaft axial. The posteromedial cortices of femoral neck were removed in groups B and C. In group A, 8 femurs with intact posteromedial cortex were fixed with three parallel partial thread screws (PTSs), forming a standard triangle. In group B, the femurs were stabilized with the same fixation of CSs like group A. In group C, two inferior PTSs were replaced by two fully thread screws (FTSs). RESULTS: The lower A-P and axial stiffness and load to failure along with higher axial displacement were found in group B compared with group A (p≤0.001 for all). Between groups B and C, the modified fixation of CSs increased A-P and axial stiffness and load to failure and reduced the axial displacement (p≤0.001 for all). CONCLUSIONS: We verified that the comminuted posteromedial cortex affected the biomechanical strength adversely and resulted in higher displacement. The modified fixation of CSs characterized by two inferior FTSs could improve the biomechanical performance and buttress the femoral head fragment better.

Technology of percutaneous cannulated screw implantation using screw view model of navigation in Garden type I of femoral neck fracture: A case report.

RATIONALE: The aim of the present study was to assess the efficacy and safety of percutaneous cannulated screw (PCS) implantation assisted by screw view model of navigation (SVMN) to treat femoral neck fracture (FNF). PATIENT CONCERNS: A 42-year-old male patient suffered from a high falling injury, causing pain, swelling, deformity, and limited mobility on his right hip. DIAGNOSES: He was diagnosed with Garden type I of FNF. INTERVENTIONS: PCS implantation assisted by SVMN was used to treat fracture of femoral neck in this patient. OUTCOMES: The follow up lasted for 48 months. A total of 3 screws were inserted into femoral neck, all exhibiting excellent position. The mean screw deviation was 0.43° and 5.73° of femoral neck-shaft and anteversion angle, respectively. The guide wire drilling attempt of each screw was one-time. The fluoroscopic time lasted 6.3 minutes, the Harris hip scores improved from 67 to 88, and the blood loss was 35 mL. It took 11.7 minutes for designing the screws, 13.9 minutes for implanting the guide wires, and 37.3 minutes for placing the screws. No clinical complications were found during 48-month follow-up visit, including head penetration, implant failure, fracture nonunion, and femoral head osteonecrosis. LESSONS: The study revealed that SVMN is conducive to the PCS insertion for FNF. Our lesson is that the FNF must be well reduction before SVMN assisted PCS placement.

Fragility Fractures in Older People in Japan Based on the National Health Insurance Claims Database.

Fragility fractures associated with age-related bone loss are of urgent concern worldwide because they reduce QOL and pose financial burdens for health care services. Currently, national data in Japan are limited. This study provides quantitative data for older patients throughout Japan who, although otherwise relatively healthy, sustained fragility fractures and were hospitalized for them. The National Database of Health Insurance Claims and Specific Health Checkups of Japan was accessed to target patients aged 65 years or older who sustained fractures between May 2013 and September 2014 and were not hospitalized for at least 13 months prior to fracture. We investigated whether the first fracture sustained was fragility related at any of four locations (proximal humerus, distal radius, vertebra, or femoral neck) and whether it necessitated hospitalization. Fragility fractures were identified in 490138 of 1188754 patients (41.2%, 345980 patients/year; 1 : 4 male-to-female ratio). Regardless of gender, vertebral fractures were most common across the age cohorts studied (43286 males and 162767 females/year), and femoral neck fractures increased markedly with increased patient age. Approximately 80% of patients with femoral neck fractures were hospitalized (62.3% of males, 71.1% of females) compared with up to 10.4% of patients with other fragility fractures. Data provided in this study can be used as a baseline for evaluating the health economy and establishing health policy in Japan.

Does fully-threaded Headless Compression Screw provide a length-stable fixation in undisplaced femoral neck fractures?

OBJECTIVE: Femoral neck shortening is a common complication after surgical treatment for intracapsular femoral neck fractures. This study investigated whether fully-threaded Headless Compression Screw (FTHCS) can be a more length-stable implant than partially-threaded cannulated screw (PTCS) in reducing femoral neck shortening. METHODS: A total of 50 patients with undisplaced femoral neck fractures (17 treated by internal fixation with three FTHCS, and 33 treated by three PTCS) from 2011 to 2014 were enrolled in this study. The radiography of the hips and medical records were reviewed for proximal femur geometry and complications. RESULTS: Significant shortening of the femoral neck length until union were noted in both group (FTHCS group: -2.5 mm, p = 0.045; PTCS group: -2.4 mm, p = 0.011). There was no significant difference in the length of femoral neck shortening between groups (p = 0.855). Age was the only significant risk factor for >5 mm of femoral neck shortening (p = 0.041). The femoral neck-shaft angle tended to reduce and become more varus in both groups (FTHCS: -2.7°, SD = 4.5, p = 0.028; PTCS: -5.0°, SD = 8.3, p = 0.002), but the differences between groups were nonsignificant (p = 0.577). The complication rates were similar between FTHCS and PTCS (17.6% and 21.2%, p > 0.999). CONCLUSION: The FTHCSs may be a substitute for PTCSs, but it cannot prevent femoral neck shortening and varus collapse after fracture fixation. Future studies should focus on how to preserve femoral neck length and hip function after femoral neck fractures.

Validation of Neck-Shaft Angle Correction After Cephalomedullary Nail Fixation.

OBJECTIVES: To validate a neck-shaft angle (NSA) correction formula using the known angle between the medullary nail and lag screw of an indwelling cephalomedullary nail (CMN). METHODS: Pertrochanteric femur fractures were created in 7 synthetic femurs and reconstructed with a CMN. Anteroposterior x-rays were taken with the proximal femur in 0, 15, 30, and 45 degrees of internal/external rotation and 10 and 20 degrees of flexion with neutral rotation. The femoral NSA and the nail angle were measured on anteroposterior x-rays. The corrected NSA was obtained by multiplying the known nail angle by the quotient of the measured NSA over the measured nail angle. RESULTS: With increasing degrees of internal or external rotation, the difference between the actual and the measured NSA increased. After correction using the known angle of the nail, the measured NSA was reduced to within 3 degrees of the actual NSA over all degrees of rotation. At neutral rotation, 15 degrees of external rotation, and 10 and 20 degrees of hip flexion, there was minimal difference between the actual NSA and the measured NSA, negating the effect of the correction formula. CONCLUSIONS: The measured NSA after CMN of intertrochanteric fractures is altered by hip rotation. This study validates the correction formula, which determines this difference by using the known angle between the lag screw and the nail.

On the internal reaction forces, energy absorption, and fracture in the hip during simulated sideways fall impact.

The majority of hip fractures have been reported to occur as a result of a fall with impact to the greater trochanter of the femur. Recently, we developed a novel cadaveric pendulum-based hip impact model and tested two cadaveric femur-pelvis constructs, embedded in a soft tissue surrogate. The outcome was a femoral neck fracture in a male specimen while a female specimen had no fracture. The aim of the present study was, first, to develop a methodology for constructing and assessing the accuracy of explicit Finite Element Models (FEMs) for simulation of sideways falls to the hip based on the experimental model. Second, to use the FEMs for quantifying the internal reaction forces and energy absorption in the hip during impact. Third, to assess the potential of the FEMs in terms of separating a femoral fracture endpoint from a non-fracture endpoint. Using a non-linear, strain rate dependent, and heterogeneous material mapping strategy for bone tissue in these models, we found the FEM-derived results to closely match the experimental test results in terms of impact forces and displacements of pelvic video markers up to the time of peak impact force with errors below 10%. We found the internal reaction forces in the femoral neck on the impact side to be approximately 35% lower than the impact force measured between soft tissue and ground for both specimens. In addition, we found the soft tissue to be the component that absorbed the largest part of the energy of the tissue types in the hip region. Finally, we found surface strain patterns derived from FEM results to match the fracture location and extent based on post testing x-rays of the specimens. This is the first study with quantitative data on the energy absorption in the pelvic region during a sideways fall.

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

BACKGROUND: The incidence of early postoperative complications of displaced intracapsular hip fractures is high. The purpose of this study was to compare the early postoperative complications and assess the incidence of femoral neck shortening on using a newly designed proximal femoral cannulated screw locking plate (CSLP) versus multiple cancellous screws (MCS) in the treatment of displaced intracapsular hip fractures in young adults. METHODS: Sixty-eight young adult patients with displaced intracapsular hip fractures were randomly assigned to either the CSLP group or the MCS group and treated routinely by internal fixation with either the CSLP or the MCS. Harris Hip Score, nonunion, failure of fixation, overall complications, and femoral neck shortening were recorded and compared. RESULTS: Two patients (5.88%) in the CSLP group and eight (23.53%) in the MCS group had postoperative nonunion (P < 0.05). There was one case (2.94%) of fixation failure in the CSLP group and three cases (8.82%) in the MCS group (P > 0.05). Three patients (8.82%) in the CSLP group and 11 (32.35%) in the MCS group had overall complications (P < 0.05). Mean femoral neck shortening was 5.10 mm in the vertical plane and 5.11 mm in the horizontal plane in the CSLP group and 11.14 mm in the vertical plane and 10.51 mm in the horizontal plane in the MCS group. Severe femoral neck shortening (≥ 10 mm) did not occur in either the vertical or the horizontal plane in any patient of the CSLP group but occurred in 10 patients (28.57%) in the vertical plane and in 8 (22.86%) patients in the horizontal plane in the MCS group. CONCLUSIONS: Compared with MCS, the use of CSLP in the treatment of displaced intracapsular hip fractures in young adults can reduce the rates of postoperative nonunion and overall complications and minimize femoral neck shortening. TRIAL REGISTRATION: ChiCTR1800016032 . Registered 8 May 2018. Retrospectively registered.

Femoral Neck Stress Injuries: Analysis of 156 Cases in a U.S. Military Population and Proposal of a New MRI Classification System.

OBJECTIVE: The objective of this study is to formulate a new MRI classification system for fatigue-type femoral neck stress injuries (FNSIs) that is based on patient management and return-to-duty (RTD) time. MATERIALS AND METHODS: A retrospective review of 156 consecutive FNSIs in 127 U.S. Army soldiers over a 24-month period was performed. The width of marrow edema for low-grade FNSIs and the measurement of macroscopic fracture as a percentage of femoral neck width for high-grade FNSIs were recorded. RTD time was available for 90 soldiers. Nonparametric testing, univariate linear regression, and survival analysis on RTD time were used in conjunction with patient management criteria to develop a new FNSI MRI classification system. RESULTS: The FNSI incidence was 0.09%, and all FNSIs were compressive-sided injuries. RTD time was significantly longer for high-grade FNSIs versus low-grade FNSIs (p < 0.001). Our FNSI MRI classification system showed a significant difference in RTD time between grades 1 and 2 (p = 0.001-0.029), 1 and 3 (p < 0.001), and 1 and 4 (p = 0.001-0.01). There was no significant RTD time difference between the remaining grades. The rates of completing basic training (BT) and requiring medical discharge were significantly associated with the FNSI MRI grades (p = 0.038 and p = 0.001, respectively). CONCLUSION: The proposed FNSI MRI classification system provides a robust framework for patient management optimization by permitting differentiation between operative and nonoperative candidates, by allowing accurate prediction of RTD time, and by estimating the risk of not completing BT and requiring medical discharge from the military.