Association of osteoporotic fractures of femoral neck and femoral neck geometric parameters in native Chinese women.

BACKGROUND: Although it is generally believed that the femoral neck fracture is related to the femoral neck geometric parameters (FNGPs), the association between the risk of osteoporotic fracture of the femoral neck and FNGPs in native Chinese women is still unclear. METHODS: A total of 374 female patients (mean age 70.2 ± 9.32 years) with osteoporotic fracture of the femoral neck, and 374 non-fracture control groups were completely matched with the case group according to the age ratio of 1:1. Using DXA bone densitometer to measured eight FNGPs: the outer diameter (OD), cross-sectional area (CSA), cortical thickness (CT), endocortical diameter (ED), buckling ratio (BR), section modulus (SM), cross-sectional moment of inertia (CSMI), and compressive strength index (CSI) at the narrowest point of the femoral neck. RESULTS: Compared with the control group, the average values of OD (2.9%), ED (4.5%), and BR (26.1%) in the patient group significantly increased (p = 0.015 to < 0.001), while CSA (‒15.3%), CT (‒18.2%), SM (‒10.3%), CSMI (‒6.4%), and CSI (‒10.8%) significantly decreased (all p < 0.001). The prevalence of osteoporosis in the lumbar spine, femoral neck, and total hip was, respectively, 82%, 81%, and 65% in fracture patients. Cox proportional hazard model analysis showed that in the age adjusted model, the fracture hazard ratio (HR) of CSA, CT, BR, SM, and CSI significantly increased (HRs = 1.60‒8.33; 95% CI = 1.08‒16.6; all p < 0.001). In the model adjusted for age and femoral neck BMD, HRs of CT (HRs = 3.90‒8.03; 95% CI = 2.45‒15.1; all p < 0.001) and BR (HRs = 1.62‒2.60; 95% CI = 1.20‒5.44; all p < 0.001) were still significantly increased. CONCLUSION: These results suggest that the majority of osteoporotic fractures of the femoral neck of native Chinese women occur in patients with osteoporosis. CT thinning or BR increase of FNGPs may be independent predictors of fragility fracture of femoral neck in native Chinese women unrelated to BMD.

Relationship Between Prepatellar Fat Thickness and Bone Mineral Density.

OBJECTIVE: To evaluate the relationship between bone mineral density (BMD) by measuring the prepatellar fat thickness with knee radiography and to gain a measurement method that has not been done before in the literature. STUDY DESIGN: Cross-sectional descriptive study. Place and Duration of the Study: Department of Physical Medicine and Rehabilitation, Training and Research Hospital, Sanliurfa, Turkiye, between January and June 2020. METHODOLOGY: Patients' age, body mass index (BMI) data, prepatellar fat thickness (mm), L1-L4 total, bone mineral density femoral neck, femur trochanter major, and femur total T scores were recorded. The relationships between these three groups (normal, osteopenia, osteoporosis) and between prepatellar fat tissue measurement were evaluated. One-way analysis of variance (ANOVA) and Post Hoc Tukey tests were used in the analysis. RESULTS:  A statistically significant difference was found in terms of trochanter major T score measurements (X2 = 20.435; p <0.001) and BMI (X2 = 66.535; p <0.001) measurements of prepatellar fat thickness measurement. A statistically significant difference was found between the three groups in terms of prepatellar fat thickness measurement, L1-4 T-score, femoral neck, and femur total values (p <0.001). CONCLUSION:  Prepatellar fat thickness in postmenopausal Turkish women was positively correlated with BMD; BMD increases as the prepatellar fat thickness increases. This explains that perapatellar fat thickness creates a mechanical load on the bones and causes an increase in BMD. KEY WORDS: Osteoporosis, Fat thickness, Bone mineral density.

Associations between co­exposure to heavy metals and vertebral compression fracture, as well as femoral neck bone mineral density: A cross-sectional study from NHANES data.

OBJECTIVE: Accumulating evidence showed that exposure to heavy metals was harmful to human health. Little is known regarding the mixing effects of multiple metal exposures on vertebral compression fracture (VCF) and femoral neck bone mineral density (BMD). This study aimed to explore the individual and joint effects of four heavy metals [manganese (Mn), lead (Pb), cadmium (Cd) and mercury (Hg)] on VCF risk and femoral neck BMD. METHODS: This cross-sectional study included 1,007 eligible individuals with vertebral fractures from National Health and Nutrition Examination Survey 2013-2014. The outcome was the risk of VCF and femoral neck BMD. Weighted multivariate logistic regression was used to explore the individual effect of four heavy metals on the VCF risk, separately. Weighted multivariate linear regression was used to explore the individual effect of four heavy metals on the femoral neck BMD, separately. Adopted bayesian kernel machine regression (BKMR) model and quantile-based g computation (qgcomp) to examine the joint effects of four heavy metals on the VCF risk and femoral neck BMD. RESULTS: Among the population, 57 individuals developed VCF. After adjusting covariates, we found no statistical differences regarding the individual effects of four heavy metals on the risk of VCF. BKMR model and qgcomp indicated that there were no statistical differences regarding the joint effects between four heavy metals on the VCF risk. In addition, we found that Cd was associated with femoral neck BMD, and an increase in the mixture of heavy metal exposures was associated with a decreased risk of femoral neck BMD. CONCLUSION: No significant correlation was observed between co-exposure to Mn, Pb, Cd and Hg and VCF risk. But co-exposure to Mn, Pb, Cd and Hg may be associated with femoral neck BMD.

Modified "SUPERhip2" to Reconstruct Postinfectious Femoral Neck Pseudoarthrosis (Hunka Type 3): A Case Report.

CASE: We report a case of a 3-year-old girl who developed a post-infectious femoral neck pseudoarthrosis after a proximal hematogenous femoral osteomyelitis (type 3 according to Hunka classification of the sequelae of the septic hip in children). The patient was treated by a modified "SUPERhip 2" procedure (a reconstructive procedure described to reconstruct congenital femoral neck pseudoarthrosis). This report describes the surgical technique in details and discusses the advantages, pitfalls, and complications and possible complications. CONCLUSION: Our modification simplifies the "SUPERhip 2" procedure. Postinfectious neck pseudoarthrosis was successfully treated, and we believe this modification is applicable for the treatment of congenital femoral neck pseudoarthrosis as well.

Clinical efficacy of Femoral Neck System for treatment of unstable femoral neck fractures in young adults.

OBJECTIVE: This study was performed to evaluate the mid-term clinical efficacy of the Femoral Neck System (FNS) (DePuy Synthes, Zuchwil, Switzerland) in treating young patients with unstable Pauwels type III femoral neck fractures. METHODS: We performed a retrospective observational analysis of 21 young adults treated with the FNS. Clinical outcomes were assessed based on fracture reduction quality, Harris hip scores, and postoperative complication rates. RESULTS: The study comprised 21 patients with a mean age of 35 years (range, 20-50 years) who were followed for a mean duration of 22.8 months (range, 16-30 months). Closed reduction was unfeasible in three (14.3%) patients, each of whom required open reduction. Notable postoperative complications were avascular necrosis in two (9.5%) patients, nonunion in one (4.7%), and implant failure in one (4.7%). Each of these complications led to the requirement for total hip arthroplasty. CONCLUSION: The favorable mid-term clinical outcomes of this study indicate that the FNS is a potentially effective treatment modality for young individuals with unstable Pauwels type III femoral neck fractures.

Biomechanical changes in the proximal femur before and after removal of femoral neck system.

BACKGROUND: As an innovative internal fixation system, FNS (femoral neck system) is increasingly being utilized by surgeons for the treatment of femoral neck fractures. At present, there have been numerous finite element analysis experiments studying the immediate stability of FNS and CSS in treating femoral neck fractures. However, there is scarce mechanical analysis available regarding the effects post internal fixation removal. This study aimed to investigate the alterations in mechanical parameters of the proximal femur before and after the removal of FNS (femoral neck system), and to assess potential distinctions in indicators following the extraction of CSS (Cannulated Screws). METHODS: A proximal femur model was reconstructed using finite element numerical techniques. The models for CSS and FNS were formulated utilizing characteristics and parametric definitions. The internal fixation was combined with a normal proximal femur model to simulate the healing state after fracture surgery. Within the framework of static analysis, consistent stress burdens were applied across the entirety of the models. The total deformation and equivalent stress of the proximal femur were recorded before and after the removal of internal fixation. RESULTS: Under the standing condition, the total deformation of the model before and after removing CSS was 0.99 mm and 1.10 mm, respectively, indicating an increase of 12%. The total deformation of the model before and after removing FNS was 0.65 mm and 0.76 mm, respectively, indicating an increase of 17%. The equivalent stress for CSS and FNS were 55.21 MPa and 250.67 MPa, respectively. The average equivalent stress on the cross-section of the femoral neck before and after removal of CSS was 7.76 MPa and 6.11 MPa, respectively. The average equivalent stress on the cross-section of the femoral neck before and after removal of FNS was 9.89 MPa and 8.79 MPa, respectively. CONCLUSIONS: The retention of internal fixation may contribute to improved stability of the proximal femur. However, there still existed risks of stress concentration in internal fixation and stress shielding in the proximal femur. Compared to CSS, the removal of FNS results in larger bone tunnels and insufficient model stability. Further clinical interventions are recommended to address this issue.

Age and sex are excellent predictors of bone complications in patients with type 2 diabetes with no history of osteoporotic fracture or treatment for osteoporosis.

OBJECTIVE: To identify patients with type 2 diabetes mellitus (T2DM) with no history of fracture or osteoporosis treatment who are at risk of bone complications through the assessment of bone quality and quantity. METHODS: Of the outpatients attending our clinic during 2021 to 2022, we retrospectively enrolled 137 (men/women: 85/52, median age: 65 years) consecutive patients aged ≥40 years who had T2DM but no history of fracture or osteoporosis treatment. The lumbar spine and femoral neck bone mineral density and the trabecular bone score were determined using dual-energy X-ray absorptiometry. Independent factors associated with bone disease were identified using logistic regression analysis, and odds ratios (ORs) were calculated. RESULTS: Age and female sex were significantly associated with high ORs for development of bone disease. The integrated risk of bone complications was nearly 40-fold higher in older (≥65 years) women than in younger (<65 years) men. This difference remained after adjustment for the duration of T2DM, body mass index, and HbA1c level. CONCLUSIONS: Older women have the highest risk of osteopenia and osteoporosis among patients with T2DM who have no history of fracture or osteoporosis treatment. These patients should undergo intensive monitoring for bone fragility from an early stage of their disease.

Pre-sliding technique to improve femoral neck system against the shortening: a retrospective cohort study.

OBJECTIVE: To investigate the efficacy of using pre-sliding technique to prevent postoperative shortening of displaced femoral neck fracture fixed with femoral neck system (FNS). METHODS: Retrospective analysis of 110 cases of displaced femoral neck fracture treated with femoral neck system from September 2019 to November 2022 in our center, which were divided into 56 cases in the pre-sliding group and 54 cases in the traditional group. The baseline data such as gender, age, side, mechanism of injury, fracture type, operation time, intraoperative bleeding were recorded and compared between the two groups, and the quality of fracture reduction, shortening distance, Tip Apex Distance (TAD), union time, Harris score of the hip were also compared between the two groups. RESULTS: The TAD value of the pre-sliding group was smaller than that of the traditional group, and the difference was statistically significant (P < 0.001). The shortening distance in both groups on postoperative day 1 was smaller in the pre-sliding group than in the traditional group, but the difference was not statistically significant (P = 0.07), and the shortening distance was smaller than in the traditional group at 1, 3, 6, and 12 months postoperatively, and the difference was statistically significant (all P < 0.001). Of the 110 cases, 34 (30.9%) had moderate or severe shortening, of which 24 (44.4%) were in the traditional group and 10 (17.9%) in the pre-sliding group, and the difference was statistically significant (P < 0.001), and the Harris score at 1 year, which was higher in the pre-sliding group than in the traditional group, and the difference between the two groups was statistically significant (P < 0.001). There was no statistically significant difference in the comparison of baseline data such as gender, age, side, mechanism of injury, fracture type, operation time, intraoperative bleeding, and quality of reduction between the two groups (all P > 0.05), and no statistically significant difference in fracture healing time between the two groups (P = 0.113). CONCLUSION: The use of the pre-sliding technique of displaced femoral neck fracture fixed with FNS reduces the incidence of moderate and severe shortening, improves the postoperative TAD value, and improves the hip function scores, with a satisfactory midterm efficacy.

Diabetes and osteoporosis: a two-sample mendelian randomization study.

BACKGROUND: The effects on bone mineral density (BMD)/fracture between type 1 (T1D) and type 2 (T2D) diabetes are unknown. Therefore, we aimed to investigate the causal relationship between the two types of diabetes and BMD/fracture using a Mendelian randomization (MR) design. METHODS: A two-sample MR study was conducted to examine the causal relationship between diabetes and BMD/fracture, with three phenotypes (T1D, T2D, and glycosylated hemoglobin [HbA1c]) of diabetes as exposures and five phenotypes (femoral neck BMD [FN-BMD], lumbar spine BMD [LS-BMD], heel-BMD, total body BMD [TB-BMD], and fracture) as outcomes, combining MR-Egger, weighted median, simple mode, and inverse variance weighted (IVW) sensitivity assessments. Additionally, horizontal pleiotropy was evaluated and corrected using the residual sum and outlier approaches. RESULTS: The IVW method showed that genetically predicted T1D was negatively associated with TB-BMD (ß = -0.018, 95% CI: -0.030, -0.006), while T2D was positively associated with FN-BMD (ß = 0.033, 95% CI: 0.003, 0.062), heel-BMD (ß = 0.018, 95% CI: 0.006, 0.031), and TB-BMD (ß = 0.050, 95% CI: 0.022, 0.079). Further, HbA1c was not associated with the five outcomes (ß ranged from - 0.012 to 0.075). CONCLUSIONS: Our results showed that T1D and T2D have different effects on BMD at the genetic level. BMD decreased in patients with T1D and increased in those with T2D. These findings highlight the complex interplay between diabetes and bone health, suggesting potential age-specific effects and genetic influences. To better understand the mechanisms of bone metabolism in patients with diabetes, further longitudinal studies are required to explain BMD changes in different types of diabetes.

Genetically determined type 1 diabetes mellitus and risk of osteoporosis.

BACKGROUND: Observational evidence suggests that type 1 diabetes mellitus (T1DM) is associated with the risk of osteoporosis (OP). Nevertheless, it is not apparent whether these correlations indicate a causal relationship. To elucidate the causal relationship, a two-sample Mendelian randomization (MR) analysis was performed. METHODS: T1DM data was obtained from the large genome-wide association study (GWAS), in which 6683 cases and 12,173 controls from 12 European cohorts were involved. Bone mineral density (BMD) samples at four sites were extracted from the GEnetic Factors for OSteoporosis (GEFOS) consortium, including forearm (FA) (n = 8,143), femoral neck (FN) (n = 32,735), lumbar spine (LS) (n = 28,498), and heel (eBMD) (n = 426,824). The former three samples were from mixed populations and the last one was from European. Inverse variance weighting, MR-Egger, and weighted median tests were used to test the causal relationship between T1DM and OP. A series of sensitivity analyses were then conducted to verify the robustness of the results. RESULTS: Twenty-three independent SNPs were associated with FN-BMD and LS-BMD, twenty-seven were associated with FA-BMD, and thirty-one were associated with eBMD. Inverse variance-weighted estimates indicated a causal effect of T1DM on FN-BMD (odds ratio (OR) =1.033, 95 % confidence interval (CI): 1.012-1.054, p = 0.002) and LS-BMD (OR = 1.032, 95 % CI: 1.005-1.060, p = 0.022) on OP risk. Other MR methods, including weighted median and MR-Egger, calculated consistent trends. While no significant causation was found between T1DM and the other sites (FA-BMD: OR = 1.008, 95 % CI: 0.975-1.043, p = 0.632; eBMD: OR = 0.993, 95 % CI: 0.985-1.001, p = 0.106). No significant heterogeneity (except for eBMD) or horizontal pleiotropy was found for instrumental variables, suggesting these results were reliable and robust. CONCLUSIONS: This study shows a causal relationship between T1DM and the risk of some sites of OP (FN-BMD, LS-BMD), allowing for continued research to discover the clinical and experimental mechanisms of T1DM and OP. It also contributes to the recommendation if patients with T1DM need targeted care to promote bone health and timely prevention of osteoporosis.

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

BACKGROUND: The purpose of this study was to compare the outcomes of femoral neck shortening between the femoral neck system (FNS) and the cannulated cancellous screws (CCS) for displaced femoral neck fractures in young adults PATIENTS AND METHODS: In this retrospective analysis, 225 patients aged 18-65 years with displaced femoral neck fracture were divided into two groups according to internal fixation: 135 patients in the FNS group and 90 patients in the CCS group. The length of hospital stay, duration of surgery, intraoperative blood loss, quality of reduction, extent of femoral neck shortening, incidence of femoral neck shortening, femoral neck shortening at each follow-up visit, Harris hip score (HHS), reoperation, and complications were compared between the two groups. RESULTS: The median follow-up time was 28.2 (26.0, 31.2) months in the FNS group and 30.2 (26.3, 34.7) months in the CCS group. The follow-up time, age, sex distribution, body mass index (BMI), mechanism of injury, injured side, length of hospital stay, time from injury to surgery, and fracture classification were similar between the groups. Duration of surgery was longer in the FNS group (65.0 (55.0, 87.0) min versus 55.0 (50.0, 65.0) min, P<0.001); intraoperative blood loss was greater in the FNS group (50.0 (20.0, 60.0) ml versus 20.0 (10.0, 35.0) ml, P<0.001). Femoral neck shortening was 2.4 (1.0, 4.5) mm in the FNS group versus 0.6 (0.0, 2.6) mm in the CCS group at 1 month postoperatively (P<0.001); 3.7 (1.8, 6.4) mm in the FNS group versus 1.2 (0.6, 3.8) mm in the CCS group at 3 months (P<0.001); 4.1(2.4, 7.7) mm in the FNS group versus 2.3 (1.1, 4.4) mm in the CCS group at 6 months (P<0.001); 4.2 (2.6, 7.7) mm in the FNS group versus 2.6 (1.3, 4.6) mm in the CCS group at 12 months (P<0.001); and 4.5 (2.8, 8.0) mm in the FNS group versus 2.8 (1.5, 4.8) mm in the CCS group at 18 months (P<0.001). The two groups showed no significant differences in HHS, reoperation, and reduction quality. CONCLUSION: Compared to CCS, FNS is deficient in preventing femoral neck shortening. Future research should focus on improving FNS in terms of preventing femoral neck shortening.

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.

"The least significant change on bone mineral density scan increased in patients with higher degrees of obesity".

BACKGROUND: The least significant change (LSC) threshold of 0.03 g/cm² is used to interpret bone mineral density (BMD) scans in the general population. Our working hypothesis was that the current LSC threshold would not be applicable in obese populations. AIMS: The aim of this study was to calculate the LSC in an obese population. METHODS: We performed an interventional study among 120 obesity patients, in whom two measurements of BMD were performed at 3 sites. Pairs of measures were used to calculate the LSC, using the Bland and Altman method. RESULTS: We calculated that the LSC was 0.046 g/cm² at the lumbar spine, 0.069 g/cm² at the femoral neck, and 0.06 g/cm² at the total hip. We also calculated the LSC for each class of obesity and observed an increase in LSC with increasing body mass index (BMI). We calculated a LSC of 0.05 g/cm² in patients with class 2 or class 3 obesity, whereas the LSC in patients with class 1 obesity is similar to the threshold used in the general population. DISCUSSION: In obese population, like BMD, LSC is higher than the threshold value of the general population, and increases with increasing BMI. CONCLUSION: LSC of 0.05 g/cm² could be used in clinical practice in patients with class 2 or 3 obesity. These findings should help to improve the interpretation of BMD scans in these patients and optimize their management. TRIAL REGISTRATION NUMBER: Comité de Protection des Personnes Ile-de France VII, France.

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.

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.

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.

Association of coffee intake with bone mineral density: a Mendelian randomization study.

Background: In observational studies, the relationship between coffee intake and bone mineral density (BMD) is contradictory. However, residual confounding tends to bias the results of these studies. Therefore, we used a two-sample Mendelian randomization (MR) approach to further investigate the potential causal relationship between the two. Methods: Genetic instrumental variables (IVs) associated with coffee intake were derived from genome-wide association studies (GWAS) of the Food Frequency Questionnaire (FFQ) in 428,860 British individuals and matched using phenotypes in PhenoScanner. Summarized data on BMD were obtained from 537,750 participants, including total body BMD (TB-BMD), TB-BMD in five age brackets ≥60, 45-60, 30-45, 15-30, and 0-15 years, and BMD in four body sites: the lumbar spine, the femoral neck, the heel, and the ultradistal forearm. We used inverse variance weighting (IVW) methods as the primary analytical method for causal inference. In addition, several sensitivity analyses (MR-Egger, Weighted median, MR-PRESSO, Cochran's Q test, and Leave-one-out test) were used to test the robustness of the results. Results: After Bonferroni correction, Coffee intake has a potential positive correlation with total body BMD (effect estimate [Beta]: 0.198, 95% confidence interval [Cl]: 0.05-0.35, P=0.008). In subgroup analyses, coffee intake was potentially positively associated with TB-BMD (45-60, 30-45 years) (Beta: 0.408, 95% Cl: 0.12-0.69, P=0.005; Beta: 0.486, 95% Cl: 0.12-0.85, P=0.010). In addition, a significant positive correlation with heel BMD was also observed (Beta: 0.173, 95% Cl: 0.08-0.27, P=0.002). The results of the sensitivity analysis were generally consistent. Conclusion: The results of the present study provide genetic evidence for the idea that coffee intake is beneficial for bone density. Further studies are needed to reveal the biological mechanisms and offer solid support for clinical guidelines on osteoporosis prevention.

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.

Bone health status evaluation in men by means of REMS technology.

BACKGROUND: Osteoporosis in males is largely under-diagnosed and under-treated, with most of the diagnosis confirmed only after an osteoporotic fracture. Therefore, there is an urgent need for highly accurate and precise technologies capable of identifying osteoporosis earlier, thereby avoiding complications from fragility fractures. AIMS: This study aimed to evaluate the diagnostic accuracy and precision of the non-ionizing technology Radiofrequency Echographic Multi Spectrometry (REMS) for the diagnosis of osteoporosis in a male population in comparison with conventional Dual-energy X-ray Absorptiometry (DXA). METHODS: A cohort of 603 Caucasian males aged between 30 and 90 years were involved in the study. All the enrolled patients underwent lumbar and femoral scans with both DXA and REMS. The diagnostic agreement between REMS and DXA-measured BMD was expressed by Pearson correlation coefficient and Bland-Altman method. The accuracy of the diagnostic classification was evaluated by the assessment of sensitivity and specificity considering DXA as reference. RESULTS: A significant correlation between REMS- and DXA-measured T-score values (r = 0.91, p < 0.0001) for lumbar spine and for femoral neck (r = 0.90, p < 0.0001) documented the substantial equivalence of the two measurement techniques. Bland-Altman outcomes showed that the average difference in T-score measurement is very close to zero (-0.06 ± 0.60 g/cm2 for lumbar spine and - 0.07 ± 0.44 g/cm2 for femoral neck) confirming the agreement between the two techniques. Furthermore, REMS resulted an effective technique to discriminate osteoporotic patients from the non-osteoporotic ones on both lumbar spine (sensitivity = 90.1%, specificity = 93.6%) and femoral neck (sensitivity = 90.9%, specificity = 94.6%). Precision yielded RMS-CV = 0.40% for spine and RMS-CV = 0.34% for femur. CONCLUSION: REMS, is a reliable technology for the diagnosis of osteoporosis also in men. This evidence corroborates its high diagnostic performance already observed in previous studies involving female populations.