3D-printed Multifunctional Guide Plate for Fenestration and Screws Drill in Proximal Femoral Benign Tumor.

The accurate fenestration, screw implantation and assisting stabilizing-plate placement in surgery of benign tumors in the proximal femur needs be defined easily. The aim of this study was to investigate the value of 3D printed multifunctional guides plate (3D-MGP) based on computer aided design. Between January 2020 and June 2022, 17 patients (nine females and eight males) with benign proximal femoral tumor had lesion curettage and allograft combined with internal plate fixation using 3D-MGP. In this study, the patients had CT scans and a technician reconstructed the 3D images of tumor and the femur, a doctor designed the location and margin of the fenestration and screws, and integrated different functions into MGP for benign proximal femoral lesions, which assisted in precise localization, fenestration and screw drilling. Musculoskeletal Tumor Society (MSTS) scoring was used to evaluate lower extremity function. Bone healing and the screws location was assessed with the radiographs. All patients underwent successful surgery with complete resection of the tumor and internal fixation with using the 3D-MGP. The mean follow-up was 16.4 months. The operative time was 126.47 ± 18.44 min, intraoperative bleeding was 198.23 ± 67.94 mL, intraoperative fluoroscopy was 6.47 ± 0.62, postoperative drainage was 223.82 ± 119.51 mL, and MSTS score was 27.29 ± 1.31 points. There were no unplanned fenestration and improper screw fixation. The 3D-MGP enabled personalized and accurate location of tumor, fenestration, screw placement and assisted stabilizing-plate placement for the treatment of benign tumor of the proximal femur. This technique has the potential to shorten operative times, decrease intraoperative bleeding, and reduce radiation exposure to patients.

Management of Combined Fracture Neck of Femur and Femoral Deformity in Osteogenesis Imperfecta Patient: A Case Report.

Osteogenesis imperfecta (OI) patients usually sustain repeated fractures from trivial trauma and also have skeletal deformities that affect walking. The bone fragility and repeated fractures produce deformities of the long bones especially in femur and tibia. However, neck of femur (NOF) fractures in OI are rarely described. A 11-year-old male patient known to have OI (Sillence type IV) sustained a NOF fracture after a fall. He also had proximal femoral anterolateral bowing proximally and over an intramedullary (IM) rod inserted 4 years back. He was treated by corrective osteotomy and stabilisation with an IM telescoping nail for the deformed femur and the Wagner technique for the NOF fracture. One year after operation, the patient had recovered satisfactory functional outcome with union of the NOF fracture and correction of the femoral deformity. Conclusion: The method of the Wagner technique can achieve stable fixation for femoral neck fractures and introduces the least interference with concurrent telescoping nail insertion. How to cite this article: Elbaseet HM, Ibrahim AH, Abol Oyoun N, et al. Management of Combined Fracture Neck of Femur and Femoral Deformity in Osteogenesis Imperfecta Patient: A Case Report. Strategies Trauma Limb Reconstr 2024;19(1):56-59.

Do neutrophil/lymphocyte, monocyte/lymphocyte, platelet/lymphocyte ratios affect prognosis and stage in avascular necrosis of the femoral head?

INTRODUCTION: Avascular necrosis of the femoral head (AVNFH) is an osteonecrosis type caused by ischaemic osteocyte loss of femoral head, and its exact pathomechanism is still unknown. Neutrophil, lymphocyte, monocyte, platelet levels in complete blood count and ratios between these levels have been used by almost all medical disciplines as accesible and reliable biomarkers of immune response. Aim of this study is to identify the effects of neutrophil/lymphocyte (NL), monocyte/lymphocyte (ML), platelet/lymphocyte (PLT/L) ratios on prognosis and stage in patients with avascular necrosis of the femoral head (AVNFH). MATERIALS AND METHODS: A total of 106 (30 female; 76 male) patients aged 18 and over diagnosed with avascular necrosis of femoral head between 2012-2022 years were retrospectively evaluated. Study was planned after a total of 106 (30 female, 76 male) healthy patients with consent to participate who were demographically equal to the study group were included in the control group. Patients in the study group were divided into 3 groups as Stage I, II and III according to the Ficat-Arlet classification. RESULTS: In terms of neutrophil counts; neutrophil values of study and control groups were 4.94±1.89 and 4,21±1,17; respectively. There was statistically significant difference between counts (p<0.05). In terms of neutrophil/lymphocyte ratio, NL ratio was statistically significantly higher in study group (2.11±0.85) than control group (1.75±0.44). Cut-off value of NL ratio was 2.13 according to the ROC analysis (sensitivity 47.17% (95% CI (37.4-57.1)); specificity=84.91% 95% GA (76.6-91.1)). Sensitivity and specificity of cut-off value was statistically significant. There was no difference between groups created according to Ficat-Arlet in terms of hemogram parameters. DISCUSSION: NL may indicate AVNFH; however, other parameters are considered as inadequate for identifying an independent marker in AVNFH due to ineffective immune response. Future studies with larger samples which allow standard and multi-dimensional analysis are needed (Tab. 4, Fig. 5, Ref. 20).

Management of complete intra-articular distal femur and patellar fractures in an achondroplastic young adult; small is challenging' revisited: a case-report.

BACKGROUND: People with achondroplasia exhibit distinct physical characteristics, but their cognitive abilities remain within the normal range. The challenges encountered during surgical procedures and perioperative care for achondroplastic individuals, are underrepresented in the existing literature. CASE PRESENTATION: In this report, the management of a 26-year-old North-African achondroplastic male is highlighted. The patient suffered a complete intra-articular distal femur fracture (AO/OTA 33-C1) and an ipsilateral patella fracture (AO/OTA 34-C1). The patient's unusual anatomical variations and the lack of suitable orthopedic implants posed significant surgical challenges, particularly in the context of a resource-limited developing country. Facial and spinal deformities, which are common in patients with achondroplasia, further complicated the anesthetic approach. CONCLUSIONS: The limited information on operative management of fractures in achondroplastic patients necessitated independent decision-making and diverging from the convenient approach where clear guidance is available in the literature.

Periprosthetic Hip Fractures around the Stem: Can the Stem Design Affect Fracture Features?

Background: Total hip arthroplasty is one of the most successful orthopedic surgeries; nevertheless, many of these surgeries are the causes of failure, and among them, periprosthetic fractures are one of the major causes of revision. Our study focuses on periprosthetic hip fractures with two different stem designs. The aim of the study was to analyze the obtained results, focusing on the features of periprosthetic stem fractures observed. Methods: We retrospectively reviewed periprosthetic fractures occurring between 2010 and 2023, involving Alloclassic® or CLS® uncemented femoral stems. We analyzed demographic data, proximal femur morphology, and the fracture type. Results: We identified 97 patients. Considering the proximal femur morphology, we found that there was statistically significant prevalence of Dorr A proximal femur morphology in the CLS® group and of Dorr C in the Alloclassic® group. Considering the distribution of the fracture pattern, we reported a non-statistically significant prevalence of the fracture pattern with stable stems in the CLS® group. Conclusions: The choice of the prosthetic design of the femoral stem is a crucial element when planning total hip arthroplasty. However, we found a non-statistically significant difference between the two stems considered, raising questions about the real role of stem design as a primary determinant of periprosthetic hip fractures.

Comprehensive Review on Distal Femur Fractures: From Epidemiology to Treatment Strategies.

Distal femur fractures present a substantial orthopedic challenge, necessitating a comprehensive exploration spanning epidemiology, anatomy, classification, diagnosis, and treatment strategies. This review thoroughly analyzes the multifaceted aspects surrounding distal femur fractures. It delves into the definition and epidemiology, shedding light on the incidence, age distribution, and associated risk factors. An exhaustive examination of the distal femur's anatomy, encompassing ligaments and tendons, establishes the groundwork for understanding fracture patterns and subsequent classification according to the AO Foundation/Orthopaedic Trauma Association (AO/OTA) system. Diagnostic considerations encompass physical examination and various imaging modalities, emphasizing the critical importance of prompt and accurate assessment. The extensive discussion on treatment options ranges from non-surgical management, including casting and traction, to surgical interventions, such as open reduction and internal fixation, intramedullary nailing, and external fixation. The implications for clinical practice underscore the necessity for tailored approaches based on fracture characteristics to optimize patient outcomes. However, this review also emphasizes areas necessitating further investigation, including exploring predictive biomarkers, advanced surgical techniques, and innovative rehabilitation protocols. Insights from long-term outcomes and quality-of-life assessments in diverse populations offer promising avenues for enhancing the comprehensive management of distal femur fractures. Continuous research in these areas can refine treatment strategies and elevate the standard of care for individuals grappling with this intricate orthopedic condition.

Effectiveness of Proximal Femur Nail in the Management of Unstable Per-Trochanteric Fractures: A Retrospective Cohort Study.

Background  Intertrochanteric (IT) fractures in the elderly demand surgical intervention for optimal recovery. While dynamic hip screw (DHS) is standard for stable fractures, its use in unstable cases is debated. Proximal femur nail (PFN) addresses unstable per-trochanteric fractures, boasting biomechanical advantages. Many studies favor PFN over DHS, despite concerns like screw migration. In resource-constrained developing nations, the choice of implant is pivotal. This research assesses proximal femur nailing outcomes for unstable fractures, providing insights for regional orthopedic protocols and contributing to tailored treatment guidelines in contexts with limited resources. Objective To assess the clinical and radiological outcomes in patients undergoing proximal femur nailing for unstable per-trochanteric fractures. Material and Methods This retrospective single-arm cohort study was conducted from January 2020 to July 2022. All the consecutive patients who underwent PFN for unstable per-trochanteric fractures were included in this study. Harris Hip Score (HHS) and ambulation status were recorded to evaluate functional outcomes. In contrast, the radiological outcome was assessed by calculating Radiographic Union Score for Hip (RUSH) scores at six weeks, three months, and six months post-operatively. Results  A total of 48 patients were included in this study with equal gender distribution and a mean age of 66 years. The functional outcome was recorded with 2.1% (1), 33.3% (16), and 50% (24) of patients achieving full weight bearing (FWB) without pain at six weeks, three months, and six months respectively while 14.6% (7) of the patients never achieved FWB. The radiological outcome was assessed by calculating RUSH score with 6.3% (3), 43.8% (21), and 50% (24) of the patients achieving complete union at the end of six weeks, three months, and six months respectively. One patient (2.1%) experienced malunion. Conclusion PFN remains an optimal treatment modality for the fixation of unstable per-trochanteric fractures yielding promising functional and radiological outcomes.

Geriatric proximal femur fracture updates.

Proximal femur fractures in the aging population present a variety of challenges. Physiologically, patients incurring this fracture are typically frail, with significant medical comorbidities, yet require early surgical treatment to restore mobility to prevent deterioration. Socioeconomically, the occurrence of a fragility fracture may be the beginning of the loss of independence, and the burdens of rehabilitation and support are borne by the individual patient and health care systems.

The presence of a deep lateral femoral notch sign in ACL-injured patients is associated with a 2.7° steeper posterior tibial slope and a 19% higher frequency of lateral meniscal injuries.

PURPOSE: The purpose of this study was to study the relationship between the presence of a deep lateral femoral notch sign (DLFNS) in anterior cruciate ligament (ACL)-injured patients and a higher posterior lateral tibial slope (LPTS), a reduced meniscal bone angle (MBA), a higher LPTS/MBA ratio and a higher incidence of concomitant injuries in primary ACL tears. METHODS: A retrospective case-control study was performed in patients submitted to primary ACL reconstruction with an available preoperative magnetic resonance imaging (MRI) scan. Patients with ACL tears and a femoral impactation with a depth ≥2 mm were assorted to the DLFNS group and patients with ACL tear and without a DLFNS to the control group. LPTS and MBA were measured in MRI. The presence of concomitant injuries (meniscal, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament and bone injuries) was assessed in MRI. Quantitative data are presented in the median ± interquartile range (IQR). RESULTS: There were 206 patients included in the study, with 46 patients assorted to the DLFNS group and 160 patients to the control group. In the DLFNS group, the median LPTS was 6.7° (IQR: 4.0-8.2) versus 4.0° in the control group (IQR: 2.2-6.5) (p = 0.003). The LPTS/MBA ratio was significantly higher in the DLFNS group, with a median of 0.32 (IQR: 0.19-0.44), in comparison to the control group, with a median of 0.19 (IQR: 0.11-0.31) (p < 0.001). The multivariable logistic regression analysis showed that the LPTS is an independent risk factor to having a DLFNS (odds ratio [OR] = 1.161; 95% confidence interval [CI]: 1.042-1.293, p = 0.007). There was a higher incidence of concomitant lateral meniscal injuries in the DLFNS group (67% vs. 48%, p = 0.017). CONCLUSIONS: In patients with ACL tears, the presence of a DLFNS is associated with a steeper lateral posterior tibial slope, as well as a higher incidence of concomitant lateral meniscal injuries. LEVEL OF EVIDENCE: Level III.

[Is the 95°blade plate still important in the treatment of proximal femoral pseudarthrosis?] / Hat die 95°-Winkelplatte bei der Behandlung von proximalen Femurpseudarthrosen noch einen Stellenwert?

Due to demographic changes, fractures and subsequently delayed fracture healing as well as pseudarthrosis of the proximal femur are on the increase. In the acute fracture situation, a load-stable treatment with an intramedullary implant (cephalomedullary nail) is generally sought. To date, there is no uniform consensus on the optimal treatment for complicated cases. The aim of this study was to evaluate the clinical and radiological outcome after revision of pseudarthrosis using a 95° blade plate in aseptic proximal femoral pseudarthrosis and to identify the specifications of blade plate treatment.The retrospective study design was used to evaluate data, some of which were prospectively collected. The study period covered January 2010 to December 2020 and 22 patients (10 women, 12 men) with an average age of 59 years were included in this single-center study. All patients showed pseudarthrosis after a femoral fracture type AO 31 A1-A3 or proximal femoral fracture type AO 32 A-C. Clinical and radiological follow-up were performed after 3, 6 and 12 months. Functional outcomes were assessed using the modified Harris hip score (mHHS), the numerical rating scale (NRS) and the short form health survey (SF-12).The postoperative radiological results after reosteosynthesis using a blade plate showed good results and 86.4% of the patient population were healed during the observation period. Pseudarthrosis persisted in four patients and was surgically revised.The functional results showed good results on average, albeit with a high dispersion of 17-91 points in the mHHS. The SF-12 averaged 42.6 (±10.4) points and the psychological score 49.4 (±9.6) points. The postoperative pain level was low both at rest and under stress.It was shown that reosteosynthesis with a blade plate is a surgically demanding but effective treatment option with a low potential for infection and safe bone consolidation, especially for the correction of high-grade axial deviation or varus malalignment.

Cantilever Failure of Modular Uncemented Femoral Revision Stem in Patients with Poor Proximal Femoral Support; How to avoid it?

Objectives: Revision hip arthroplasty is a major surgical challenge and is even more difficult in cases with a deficient proximal femur. Modular uncemented cone body revision femoral stems were introduced as a solution. They have the advantage of optimising joint kinematics by allowing the variable degrees of version, offset and leg length. However, we noticed cantilever failure of such stems, particularly in patients with deficient proximal femoral support. Fatigue fracture of the revision femoral stems should raise questions about its use in patients with insufficient proximal femoral bone support. Methods: We present a case series of five patients with the cantilever failure of Stryker restoration modular stem conical distal femur prosthesis. These cases were identified during a retrospective review of revision hip surgeries performed at our trust. Results: The stem failed after an average of 22.6 months post-revision surgery. Primarily, poor proximal femur bone support with a well-fixed distal stem and secondarily high BMI led to this catastrophic failure in the absence of trauma. All five cases were re-revised to Stanmore proximal femoral replacement and achieved good functional outcomes after an average follow-up of seven years. Conclusion: Proximal femoral bone support should be restored to prevent early cantilever failure of distally fixed proximal modular revision femoral stems. Consider a proximal femoral replacement if we cannot ensure proximal bone support.

A systematic review and meta-analysis of long-term outcomes of femoral derotation surgery for intoeing gait in cerebral palsy.

BACKGROUND: Femoral derotation osteotomy is treatment of choice in intoeing gait secondary to cerebral palsy (CP). RESEARCH QUESTION: The aim of this study was to critically appraise the literature regarding the long-term outcomes of femoral derotation surgery in CP. METHODS: Electronic databases of PubMed and Scopus was used for the literature review by two researchers independently (SB, SC). The study population included patients of cerebral palsy undergoing femoral derotation surgery. The keywords used were "cerebral palsy", "intoeing gait", "femur anteversion", "hip anteversion", "femur derotation" and "femur osteotomy". RESULTS: Nine studies which included 657 limbs in 407 patients were selected for this study of which eight were retrospective in nature. The improvement in hip rotation at stance at last follow up (more than five years) maintained a statistical significance (SMD 1.67 95 %CI 1.12-2.22). Similar statistically significant outcomes were noted for foot progression angle (SMD 1.19 95 %CI 0.92-1.47), anteversion (SMD 2.75 95 %CI 1.49-4.01) and total passive internal rotation (SMD 1.71 95 %CI 1.19-2.22). SIGNIFICANCE: Femoral derotation surgery is the procedure of choice for correction of intoeing gait in CP. Even though, there is deterioration of results on long-term as compared to short term, majority of the patients shall maintain overall correction without recurrence of an intoeing gait. Future studies with uniform criteria for defining recurrence on the basis of functional limitations shall provide better idea about the natural course of this procedure.

Total Hip Arthroplasty in a Patient With a Large Proximal Femur Aneurysmal Bone Cyst: A Case Report and Literature Review.

Aneurysmal bone cysts (ABCs) are rare benign bone lesions with a predilection for the metaphysis of long bones. They are often cystic, expansive, and osteolytic and may result in bony deformity. In general, there remains debate about optimal treatment for ABCs; however, the mainstay typically consists of a combination of curettage, bone grafting, and considering the need for internal fixation and osteotomies. The goals of treatment include preserving bony anatomy while eliminating the lesion. There is sparse literature regarding the treatment of osteoarthritis adjacent to benign bony tumors. If total hip arthroplasty is chosen as a treatment option, diligent preoperative planning is required, and the surgeon must assess the patient's bone stock, account for bony deformity, and utilize specific implants and techniques based on the patient's characteristics. We present a case of an adult patient with proximal femur ABC and symptomatic adjacent hip osteoarthritis who underwent treatment with total hip arthroplasty.

The burden of periprosthetic femoral fractures in England and Wales: Insights from the first two years of data collection in the National Hip Fracture Database and regional variation in care.

INTRODUCTION: Periprosthetic femoral fractures (PPFFs) represent an important healthcare problem, with a rising incidence noted due to an increase in the number of arthroplasty surgeries being performed. There is a current lack of national consensus as to how these complex, often frail patients are managed. AIMS: Our primary aim was to present the epidemiology of PPFFs in England and Wales over the first two years of data collection by the National Hip Fracture Database (NHFD). Secondary aims included how well the NHFD Key Performance Indicators (KPIs) are met for PPFF patients, whether centres reporting a higher burden of PPFF patients are more likely to meet KPIs compared to lower volume centres, and to also identify if regional variation in care for these patients exist. METHODS: Patients aged 60 years or over, admitted to any acute hospital in England or Wales with a PPFF within the period 1st January 2020 to 31st December 2021 were included. Fractures were classified using the Vancouver system. The primary outcome of interest was the incidence of PPFF in England and Wales. Secondary outcomes included i) geographical distribution, ii) pattern of injury, iii) treatment received, iv) KPI performance nationally, v) KPI performance by top 5 highest volume hospitals vs the rest, vi) KPI performance by region and vii) KPI performance compared with native hip fracture patients. RESULTS: A total of 5,566 PPFFs were reported during our study period. A 31 % increase in cases was seen between 2020 and 2021 (2,405 to 3,161). The South-West of England reported the highest burden of PPFFs (14 % of all cases reported in 2021). Vancouver B subtypes were most common around hip replacements (62 %) and C subtype around knee replacements (55 %). A total of 4,598 patients (82.6 %) underwent operative management. There was regional variation in KPI attainment. When compared to KPI attainment for native hip fractures PPFF care under performed in most regions and domains. High volume PPFF centres were not associated with improved attainment of KPIs. CONCLUSION: We have described the incidence, nature, and management of PPFF at national and regional levels using routinely collected NHFD data. Both numerically and due to case complexity, PPFF are a considerable challenge to patients and health services alike. This epidemiology is not captured by other existing datasets and increased case contribution to the NHFD is encouraged to improve understanding and enable prioritisation and delivery of further care and research.

Vascular injury during lateral close-wedge distal femoral osteotomy: A case report and review of surgical principles.

INTRODUCTION: Knee malalignment can increase the risk of osteoarthritis. Osteotomies can correct limb deformities, but they come with the risk of complications such as cortical hinge fracture, hardware failure, pain syndrome, and infection. Vascular injury is rare, but it can lead to bleeding, limb ischemia, and swelling. If revascularization is delayed for over 12 h, it can result in poor outcomes. The work has been reported in line with the SCARE criteria. CASE: A 41-year-old female underwent a lateral close-wedge distal femoral osteotomy. Postoperatively, no distal pulse was detected. An emergency vascular surgery consultation revealed popliteal vein penetration and popliteal artery thrombosis, probably during pin penetration. Revascularization was performed, and the patient was discharged without complications. At the three-year follow-up, the patient was in good health and without complications. DISCUSSION: Knowledge of the femoral artery and vein's proximity to the apex of the wedge is crucial in lateral close wedge distal femoral osteotomy. Despite vascular injury with an oscillating saw, it can happen during guide pin insertion. Although Intraoperative massive bleeding can show vascular injury, lack of it was not a protective factor. CONCLUSION: During the process of pin insertion, it is important to ensure that the pin's orientation is directly lateral to the medial. This should be checked using the C-Arm by obtaining AP, Lat, and Oblique views. To check for intraoperative bleeding, the tourniquet should be deflated. Once the procedure is complete, it is important to check for any vascular injury by examining distal pulses and limb perfusion carefully, particularly in the recovery room.

The Impact of Delayed Osteosynthesis of Bone Healing in Patients with Extra-articular Distal Femoral Fracture.

Background: In extra-articular distal femoral fractures (EDFFs), nonunion is a serious complication that occurs rarely. In this study, we examined how longer preservation of initial fracture hematoma by delaying the osteosynthesis (OS) affects the fracture union. Methods: In a retrospective cohort study, 98 EDFF patients were included. The OS was done within 2 days of injury in 50 patients (early OS group) and after 2 days of injury in 48 patients (late OS group). Time to callus formation and fracture union, bleeding amount, surgical duration, pain, knee range of motion, knee function, and postoperative complications, including the nonunion, knee deformity, infection, and revision, were compared between the 2 groups. Statistical analyses were done with SPSS. A comparison of the mean between the 2 groups was made with an independent t test or its nonparametric counterpart. A comparison of categorical variables between the 2 groups was made using a chi-square or the Fisher's exact test. P ˂ 0.05 was considered statistically significant. Results: The mean time to callus formation was 47.1 ± 17.3 days in the early OS group and 46.9 ± 19.7 in the late OS group (P = 0.950). The mean time to fracture union was 114.9 ± 21 in the early OS group and 117.4 ± 28.8 days in the late OS group (P = 0.630). The mean operation time and bleeding amount between the 2 groups did not differ significantly (P = 0.230 and P = 0.340, respectively). The knee range of motion, pain, and function were not notably different (P = 0.620, P = 0.790, and P = 0.770, respectively). Nonunion occurred in 3 patients of early OS and 2 patients of the late OS group. Other complications were also comparable in the 2 study groups. Conclusion: Delayed OA in EDFF patients has no significant effect on bone healing and fracture union. Future standard studies are required to confirm these results.

Finite element analysis of patient-specific additive-manufactured implants.

Introduction: Bone tumors, characterized by diverse locations and shapes, often necessitate surgical excision followed by custom implant placement to facilitate targeted bone reconstruction. Leveraging additive manufacturing, patient-specific implants can be precisely tailored with complex geometries and desired stiffness, enhancing their suitability for bone ingrowth. Methods: In this work, a finite element model is employed to assess patient-specific lattice implants in femur bones. Our model is validated using experimental data obtained from an animal study (n = 9). Results: The results demonstrate the accuracy of the proposed finite element model in predicting the implant mechanical behavior. The model was used to investigate the influence of reducing the elastic modulus of a solid Ti6Al4V implant by tenfold, revealing that such a reduction had no significant impact on bone behavior under maximum compression and torsion loading. This finding suggests a potential avenue for reducing the endoprosthesis modulus without compromising bone integrity. Discussion: Our research suggests that employing fully lattice implants not only facilitates bone ingrowth but also has the potential to reduce overall implant stiffness. This reduction is crucial in preventing significant bone remodeling associated with stress shielding, a challenge often associated with the high stiffness of fully solid implants. The study highlights the mechanical benefits of utilizing lattice structures in implant design for enhanced patient outcomes.

Non-traumatic Simultaneous Bilateral Femur Neck Fracture in a Young Female Unraveling End-Stage Renal Disease: A Case Report and Literature Review.

Introduction: Spontaneous femur neck fracture is rare, especially when they occur bilaterally. Renal osteodystrophy is among the causes of these fractures that should be kept in mind. We report a case of a young female who presented with bilateral hip pain and was found to have bilateral femur neck fracture due to renal osteodystrophy. This was the first presentation of an undiagnosed end-stage kidney disease. This case report aims to highlight the importance of investigating the cause of these rare fractures in young patients and discuss available surgical options. Case Report: A 19-year-old female presented complaining of bilateral hip pain. On physical examination, there was tenderness on palpation of both thighs. Her workup was significant for anemia, a high level of creatinine, hypocalcemia, elevated alkaline phosphatase, and parathyroid hormone. A pelvis radiograph showed bilateral femur neck fracture. Considering her very young age, the metabolic derangements she had and to avoid exposing her to a major surgery, we treated her fractures by fixation using three cannulated screws on each side. We aimed to report this case as it is an unusual presentation of a previously undetected stage 5 chronic kidney disease (CKD) in a very young patient. Conclusion: Renal osteodystrophy due to CKD can present with spontaneous bilateral femur neck fracture. Physicians should have a high index of suspicion for this condition not to miss a chronic disease with multiple sequelae. Furthermore, these fractures carry a high risk of complications and mortality, so they should be addressed promptly.

Femoral neck osteosynthesis using interfragmentary compression or position screw in synthetic bones. What are the mechanical differences?

PURPOSE: We aim to compare interfragmentary compression with the position osteosynthesis in the fixation of different femoral neck fractures (FN) in synthetic bones subjected to vertical load. METHODS: Forty-two synthetic femurs were subjected to neck fractures and separated into 3 groups according to the Pauwels classification: Pauwels I had 6 units (PI); Pauwels II, 24 units, with and without comminution (PII); and Pauwels III, 12 units, with and without comminution (PIII). After, they were fixed with 2 different ways: three 7, 0 mm cannulated lag screws (CSs) versus three 6, 5 mm solid fully threaded screws (SSs). Screws positioning was oriented by the Pauwels classification: inverted triangle or crossed screws. All specimens were submitted to vertical loading until failure. RESULTS: The average force was 79.4 ± 22.6 Kgf. The greatest one was recorded in model 1 (135.6 Kgf), and the lowest in model 41 (39.6 Kgf). CSs and SSs had similar resistance until failure (p = 0.2). PI showed heightened resistance and PIII showed a worse response (p < 0,01). CSs had better performance in PIII (p = 0.048). Comminution and screws orientation caused no difference on peak force (p = 0.918 and p = 0.340, respectively). CONCLUSIONS: In synthetic bones, the resistance of a femoral neck fracture osteosynthesis using a 7, 0 mm cannulated lag screw or 6, 5 mm solid fully threaded screw are similar. There was no loss of efficiency with comminution in the femoral neck. Osteosynthesis resistance decreased with the verticalization of the fracture line and, in the more vertical ones, interfragmentary compression with CSs was more resistant than positional osteosynthesis with SSs.

Incidence and management of secondary deformities after megaendoprosthetic proximal femur replacement in skeletally immature bone sarcoma patients.

INTRODUCTION: Megaendoprosthetic reconstruction of bone defects in skeletally immature patients has led to the development of unique complications and secondary deformities not observed in adult patient cohorts. With an increasing number of megaendoprosthetic replacements performed, orthopedic oncologists still gain experience in the incidence and type of secondary deformities caused. In this study, we report the incidence, probable cause and management outcome of two secondary deformities after megaendoprosthetic reconstruction of the proximal femur: hip dysplasia and genu valgum. MATERIALS AND METHODS: Retrospective analysis of 14 patients who underwent primary and/or repeat reconstruction/surgery with a megaendoprosthetic proximal femur replacement between 2018 and 2022. RESULTS: Mean patient age was 9.1 years (range 4-17 years). Stress shielding was observed in 71.4%. Hip dislocation was the most frequent complication (50%). While four dislocations occurred without an underlying deformity, secondary hip dysplasia was identified in 58.3% (n = 7/12) of intraarticular resections and reconstructions, leading to dislocation in 71.4% (n = 5/7). A genu valgum deformity was observed in 41.6% (n = 5/12). The incidence of secondary hip dysplasia and concomitant genu valgum was 42.9% (n = 3/7). Triple pelvic osteotomy led to rebound hip dysplasia in two cases (patients aged < 10 years), whereas acetabular socket replacement led to stable hip joints over the course of follow-up. Temporary hemiepiphyseodesis was applied to address secondary genu valgum. CONCLUSIONS: Patients aged < 10 years were prone to develop secondary hip dysplasia and genu valgum following proximal femur replacement in this study. Management of secondary deformities should depend on remaining skeletal growth. Stress shielding was observed in almost all skeletally immature patients.