Infantile Myofibromatosis of the Femoral Neck: A Case Report.

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

The effect of pre-fracture proximal femur geometry on hip fracture type in elderly patients.

This study aimed to analyze the relationship between fracture type by determining data on the geometry of the proximal femur in the pre-fracture period in patients over 65 years of age who had hip fractures as a result of low-energy trauma. A total of 127 patients who were admitted to the hospital for reasons other than hip pathology within 1 year before the occurrence of hip fracture and who had an anterior-posterior pelvic X-ray were included in the study. Measurements were made to evaluate the proximal femur geometry, neck shaft angle, central edge angle, femoral head diameter, femoral neck diameter, femoral neck length, femoral offset length, femoral neck axial length, hip axis length, and femoral shaft diameter. As a result of these measurements, analyses were performed to determine the relationship between the control group and fracture types. The mean Neck shaft angle scores were significantly higher in both fracture types than in the control group (P = .034, P = .002). The mean Femoral offset length values of both fracture types were lower than those of the control group (P = .002, P = .011, respectively). Multiple logistic regression analysis revealed that the risk of collum femoris fracture increased as the Femoral head diameter value increased. (OD = 0.21, P = .002). The geometric parameters of the proximal femur play an important role in the formation of hip fracture types. Therefore, differences in proximal femur geometry in hip fracture types should be considered, and patient-focused choices should be made regarding the surgical procedures and implants to be used during fracture fixation.

Proximal femur geometry: a major predictor of proximal femur fracture subtypes.

INTRODUCTION: Proximal femur geometry (PFG) represents an important risk factor for the occurrence of hip fractures. There are currently few studies regarding the correlation between PFG and the occurrence of a specific fracture subtype, and those that exist have small cohorts and present with different methodologies and contradictory results. Therefore, there is no consensus in the literature regarding this topic. The present study aimed to establish the contribution of the PFG in the occurrence of different subtypes of proximal femur fractures (PFF): intertrochanteric, neck and subtrochanteric. METHODS: Analysis of 1022 plain anteroposterior pelvic radiographs of patients consecutively admitted to the emergency room of a Level 1 Trauma Centre between 2013 and 2019 after low energy trauma who presented with PFF and underwent surgical treatment. Patients were analysed considering age, gender and subtype of PFF (intertrochanteric, neck or subtrochanteric). Radiological parameters including cervicodiaphyseal angle (CDA), horizontal offset (HO), femoral neck width (FNW), femoral neck length (FNL), great trochanter-pubic symphysis distance (GTPSD), acetabular teardrop distance (ATD) and width of the intertrochanteric region (WIR) were measured and compared between the different subtypes of fractures (7154 measurements). Statistical analysis was conducted recurring to absolute measurements and measurements ratios. The correlation was assessed using t-test. RESULTS: There were statistically significant differences in proximal femur geometry between the different subtypes of fractures. Patients presenting with femoral neck fractures had greater CDA (132.5 ± 6.9 vs. 130.0 ± 7.3; p < 0.001) and lower HO (45.8 ± 7.4 vs. 49.0 ± 8.0; p < 0.001), HO/ATD (0.34 ± 0.068 vs. 0.37 ± 0.072; p < 0.001) and HO/GTPSD (0.26 ± 0.049 vs. 0.28 ± 0.039; p < 0.001) than patients with intertrochanteric/subtrochanteric fractures. CONCLUSIONS: PFG represents an important contributor to the occurrence of different fracture subtypes. Femoral neck fractures are associated with greater CDA and lower HO, HO/ATD and HO/GTPSD when compared to intertrochanteric or subtrochanteric fractures.

Relationship of sarcopenia with bone geometry and mass among postmenopausal women.

OBJECTIVE: The aim of this study was to verify whether sarcopenia and its components are associated with hip areal bone mineral density (aBMD) and geometry in postmenopausal women (PW). METHODS: In this cross-sectional study, appendicular bone-free lean mass (aLM) and hip bone mass and geometry were measured using dual-energy x-ray emission absorptiometry (DXA). Muscle power and strength were measured by five times Sit-to-Stand Test (5-STS) and dynamometry, respectively, in 175 PW. Sarcopenia was identified as low aLM plus low muscle strength or low muscle power. Multiple linear regression (covaried by age, smoking, hormonal therapy, and diseases) was used to determine the relationship between sarcopenia and bone geometry and mass. The results are presented as mean differences between groups. RESULTS: Dynamometry, five times Sit-to-Stand Test, and aLM indicated positive associations (P < 0.05) with most indicators of bone mass and geometry. Sarcopenia, applying low muscle strength or low muscle power, was negatively associated with femoral neck width (-0.2 mm, P = 0.001), cortical thickness of femoral calcar (-0.6 mm, P = 0.043), subtrochanteric cortical thickness (-1.2 mm, P = 0.002), femoral neck cross-sectional area (-19.5 mm2, P < 0.001), cross-section moment of inertia (-2,244 mm4, P < 0.001), section modulus (-115 mm3, P < 0.001), femoral neck aBMD (-0.1 g/cm2, P = 0.002), upper femoral neck aBMD (-0.1 g/cm2, P = 0.003), lower femoral neck aBMD (-0.1 g/cm2, P = 0.016), and trochanteric aBMD (-0.1 g/cm2, P = 0.035). CONCLUSIONS: Thus, muscle mass, strength and power, alone or in combination (ie, sarcopenia), are associated with low aBMD, impaired bone geometry, and, therefore, bone strength in PW. These measures may help identify PW at risk of hip fractures.

Is Femoral Neck System a Valid Alternative for the Treatment of Displaced Femoral Neck Fractures in Adolescents? A Comparative Study of Femoral Neck System versus Cannulated Compression Screw.

Background and Objectives: The femoral neck system (FNS) is a new minimally invasive internal fixation system for femoral neck fractures (FNFs), but its use has not been reported in adolescents. The aim of this study was to compare the clinical and radiographic outcomes of displaced FNF in adolescents treated with FNS or a cannulated compression screw (CCS). Materials and Methods: A retrospective study of 58 consecutive patients with displaced FNF treated surgically was performed; overall, 28 patients underwent FNS and 30 CCS fixation. Sex, age at injury, type of fracture, associated lesions, duration of surgery, radiation exposure, and blood loss were collected from the hospital database. The clinical and radiographic results, as well as complications, were recorded and compared. Results: The patients were followed up for 16.4 ± 3.1 months on average after index surgery (range, 12 to 24). Consolidation time among patients treated with FNS was significantly lower than those managed by CCS (p = 0.000). The functional scores of patients treated with FNS were significantly higher than those managed by CCS (p = 0.030). Unplanned hardware removal in patients treated with FNS was significantly lower than in those managed by CCS (p = 0.024). Conclusions: FNS has a lower complication rate and better functional outcome than CCS. It may be a good alternative to treat femoral neck fractures in adolescents.

Analysis of the femoral neck from rats in the periestropause treated with oxytocin and submitted to strength training.

Among the interventions used to prevent osteoporosis in female organisms, strength training (ST) and oxytocin (OT) stand out, as a promising hormone with anabolic action on bone. This study aimed to verify whether the combined action of OT and ST, compared to isolated interventions, potentiates the bone remodeling process of the femoral neck of Wistar rats during periestropause. Forty Wistar rats (18 months) with irregular estrous cycle were randomly distributed into groups: 1-Vehicle (Veh; NaCl 0.15 mol/L ip); 2-Oxytocin (Ot; 134 µg/kg/ip); 3-Strength training (St); 4-Ot + St. The animals of the 1, 2 and 4 groups received two intraperitoneal injections with an interval of 12 h every 30 days, totaling 8 injections at the end of the experimental period (18 to 21 months). The animals in the St and Ot + St groups performed ST on a ladder 3 times a week, maximal voluntary carrying capacity (MVCC) test monthly. After 120 days, the animals were euthanized; the femur was collected for analysis of biomechanical testing, densitometry, bone microtomography, Raman spectroscopy, tissue PCR, and blood for analysis of bone biomarkers, liver damage, and oxidative stress. The main effects in the Ot group were observed in the maximum load and energy in the compression testing (femoral head), and stiffness and energy in the three-points bending testing (femur diaphysis). In addition, the main effects occurred on the bone mineral density (BMD), cortical thickness (Ct.Th), number of pores (Po.N), polar moment of inertia (J), trabecular thickness (Tb.Th), and connectivity density (Conn.Dn), Bone alkaline phosphatase (Alp), Tumor necrosis factor receptor superfamily member 11b (Opg), Tumor necrosis factor ligand superfamily member 11 (Rankl) and Cathepsin K (Ctsk) expression. There was an effect in the tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP). In the St group, the main effect was observed on the energy (compression and the three-points bending), stiffness, aBMD, BMD, cortical bone area (Ct.Ar), Po.N, trabecular bone volume (BV/TV), Tb.Th and in the mineralization ratio (ѵ1PO4/proline), Runt-related transcription factor 2 (Runx2), Bone morphogenetic protein 2 (Bmp2), Alp, Osteopontin/secreted phosphoprotein 1 (Opn/Spp1), Opg, Tumor necrosis factor receptor superfamily member 11ª (Rank), Rankl, Ctsk expression. There was an effect in the TRAP and ALP. The interaction in the combination of therapies in the Ot + St group was verified in energy to maximum load (compression and three-points bending testing), stiffness, BMD, Ct.Th, J, Tb.Th and ѵ1PO4/proline. In the gene analysis there was interaction in the Runx2, Osterix/Sp7 transcription factor (Osx/Sp7), Bmp2, Alp, Osteocalcin/Bone gamma-carboxyglutamate protein (Ocn/Bglap), Opg, Rankl and Acid phosphatase 5, tartrate resistant (Trap/Acp5) expression. In addition, the combination of OT and ST resulted in a higher maximum load compared to the Veh group, with higher BV/TV than the Ot group, higher Rankl and Ctsk expression than Veh and Ot groups, and lower Po.N and lower activity of TRAP than the other groups. In oxidative stress, total antioxidant capacity (TAC) was lower. These results showed that the combination of interventions is a promising anabolic strategy for the prevention of osteoporosis in the period of periestropause, standing out from the effects of isolated interventions.

Comparison between headless cannulated screws and partially threaded screws in femoral neck fracture treatment: a retrospective cohort study.

The choices of the treatments for femoral neck fractures (FNF) remain controversial. The purpose of this study is to evaluate the prognoses of the variable pitch fully threaded headless cannulated screws (HCS) in the fixation of femoral neck fractures and to compare them with those of partially threaded cannulated screws (PCS). Between 1st January 2012 and 31st December 2016, there were 89 patients with the main diagnose of FNF who accepted the treatment of closed reduction cannulated screw fixation in Peking University People's Hospital. 34 cases of PCS and 23 cases of HCS met the criterion. The characteristics, prognoses and the imaging changes of all cases were described and the differences between the two groups were compared. Statistical analyses were performed using SPSS version 23.0 (SPSS Inc., USA). Mann-Whitney U test, Analysis of Variance and Chi-square test were used. Statistical significance was defined as P value (two sided) less than 0.05. There was no significant difference in the general characteristics, fracture classifications and reduction quality between the two groups. HCS group had a significant lower angle decrease rate (30.4% vs. 58.8%, P = 0.035), femoral neck shortening rate (26.1% vs. 52.9%, P = 0.044) and screw back-sliding rate (21.7% vs. 50.0%, P = 0.032), but a higher screw cut-out rate (21.7% vs. 0.0%, P = 0.008). In non-displacement fracture subgroup, HCS had significant higher Harris Score (92 vs. 90, P = 0.048). Compared with PCS, HCS had a lower screw back-sliding rate, femoral shortening rate, angle decrease rate and similar function score, but would result in more screw cut-outs in displaced FNF. As a conclusion, HCS should not be used in displaced FNF due to its higher screw cut-out rate, and its potential advantage in non-displaced FNF needs to be further proved. Further qualified investigations with a larger scale of patients and longer follow-up are needed in the future.

Reduction in femoral neck and total hip bone mineral density following hospitalisation for diabetes-related foot ulceration.

Management of diabetes-related foot ulceration (DFU) includes pressure offloading resulting in a period of reduced activity. The metabolic effects of this are unknown. This study aims to investigate changes in bone mineral density (BMD) and body composition 12 weeks after hospitalisation for DFU. A longitudinal, prospective, observational study of 22 people hospitalised for DFU was conducted. Total body, lumbar spine, hip and forearm BMD, and total lean and fat mass were measured by dual-energy X-ray absorptiometry (DXA) during and 12 weeks after hospitalisation for DFU. Significant losses in total hip BMD of the ipsilateral limb (- 1.7%, p < 0.001), total hip BMD of the contralateral limb (- 1.4%, p = 0.005), femoral neck BMD of the ipsilateral limb (- 2.8%, p < 0.001) and femoral neck BMD of the contralateral limb (- 2.2%, p = 0.008) were observed after 12 weeks. Lumbar spine and forearm BMD were unchanged. HbA1c improved from 75 mmol/mol (9.2%) to 64 mmol/mol (8.0%) (p = 0.002). No significant changes to lean and fat mass were demonstrated. Total hip and femoral neck BMD decreased bilaterally 12 weeks after hospitalisation for DFU. Future research is required to confirm the persistence and clinical implications of these losses.

Can fingernail quality predict bone damage in Type 2 diabetes mellitus? a pilot study.

Type 2 diabetes mellitus (T2DM) adversely affects the normal functioning, intrinsic material properties, and structural integrity of many tissues, including bone. It is well known that the clinical utility of areal bone mineral density (aBMD) is limited to assess bone strength in individuals with T2DM. Therefore, there is a need to explore new diagnostic techniques that can better assist and improve the accuracy of assessment of bone tissue quality. The present study investigated the link between bone and fingernail material/compositional properties in type 2 diabetes mellitus (T2DM). For that, femoral head and fingernail samples were obtained from twenty-five adult female patients (with/without T2DM) with fragility femoral neck fractures undergoing hemi/total hip arthroplasty. Cylindrical cores of trabecular bone were subjected to micro-CT, and lower bone volume fraction was observed in the diabetic group than the non-diabetic group due to fewer and thinner trabeculae in individuals with T2DM. The material and compositional properties of bone/fingernail were estimated using nanoindentation and Fourier Transform Infrared Spectroscopy, respectively. Both bone/fingernails in T2DM had lower reduced modulus (Er), hardness (H), lower Amide I and Amide II area ratio (protein content), higher sugar-to-matrix ratio, and relatively high carboxymethyl-lysine (CML) content compared with non-diabetic patients. Sugar-to-matrix ratio and relative CML content were strongly and positively correlated with HbA1c for both bone/fingernail. There was a positive correlation between bone and fingernail glycation content. Our findings provide evidence that the degradation pattern of bone and fingernail properties go hand-in-hand in individuals with T2DM. Hence, the fingernail compositional/material properties might serve as a non-invasive surrogate marker of bone quality in T2DM; however, further large-scale studies need to be undertaken.

Causal Effect of Blood Pressure on Bone Mineral Density and Fracture: A Mendelian Randomization Study.

Background: Hypertension may have some association with osteoporosis. This Mendelian randomization (MR) study aimed to explore the causal effect of blood pressure (BP) on bone mineral density (BMD), fall, and fracture. Methods: We used the genome-wide association study (GWAS) summary data among 330,956 European-descent individuals to identify 107 single-nucleotide polymorphisms (SNPs) as the instrumental variables of BP. MR analyses of these instruments were performed on 53,236 European individuals for the association with forearm BMD (FA-BMD), femoral neck BMD (FN-BMD), and lumbar spine BMD (LS-BMD); 451,179 European individuals for fall susceptibility; and up to 1.2 million individuals from European descent for fracture. Conventional inverse variance weighted (IVW) method was adopted to obtain the causal estimates of BP on different outcomes, while weighted median, MR-egger, and MR pleiotropy residual sum and outlier (MR-PRESSO) test were used for sensitivity analyses. Results: Genetically high pulse pressure (PP) could significantly improve FA-BMD (beta-estimate: 0.038, 95% confidence interval [CI]: 0.013 to 0.063, SE:0.013, P-value=0.003

IL-8 correlates with reduced baseline femoral neck bone mineral density in adults with cystic fibrosis: a single center retrospective study.

Cystic fibrosis (CF) is a multi-system disease that is characterized by lung disease due to recurrent airway infection and inflammation. Endocrine complications, such as CF bone disease (CFBD), are increasingly identified as patients are living longer. The cause of CFBD is multifactorial with chronic systemic inflammation theorized to be a contributing factor. Thus, we attempted to identify inflammatory biomarkers that are associated with CFBD. We conducted a retrospective observational study of 56 adult patients with CF with an average percentage predictive forced expiratory volume in one second (ppFEV1) of 73.7% (standard deviation: 30.0) who underwent baseline serum analysis for osteoprotegerin (OPG) and pro-inflammatory biomarkers (IL-1ß, IL-6, IL-8 and TNF-α), and had repeated dual-energy x-ray absorptiometry (DXA) scans separated by at least 2 years to examine correlations between serum biomarkers and bone mineral density (BMD) measurements. Univariate linear regression model analysis demonstrated that serum IL-1ß and IL-8, but not other pro-inflammatory markers, were negatively correlated with baseline BMD results. However, after accounting for confounding variables, only the relationship between IL-8 and left femoral neck BMD remained statistically significant. Additionally, IL-8 level was associated with BMD decline over time. These results suggest that IL-8 might play a unique role in the pathophysiology of CFBD relative to other pro-inflammatory cytokines but further study is warranted before firm conclusions can be made.

Correlation between lag screw route and the ideal insertion point of the intramedullary nail.

Understanding the morphology of the superior aspect of the proximal femur is critical for treating femoral fracture. We assessed the correlation among the ideal insertion point of the femoral nail, femur head-neck axis, and native anteversion. One hundred patients with normal femurs were included in this study. Computed tomography (CT) images of the proximal femur superior aspect and amount of native anteversion were acquired. Generalised Procrustes analysis showed the morphological characteristics of the superior proximal femur according to native anteversion amount. Morphological characteristics were represented by 4 parameters; the correlation between parameters and native anteversion was investigated using CT data. The passing point of the line from the proximal femoral canal parallel to the native anteversion at the greater trochanter was located more posteriorly (mean 35.6%); the passing point of native anteversion was posterior in the femoral neck and head, although the line of the head-neck centre passed more anteriorly at the greater trochanter (mean 67.5%). This posterior translation was significantly associated with native anteversion amount. Morphometric geometric analysis showed that the lag screw could not pass head-neck centre from the nail inserted into proximal femoral canal. Anterior insertion of the nail was needed for positioning the lag screw centre.

Primary cam morphology; bump, burden or bog-standard? A concept analysis.

BACKGROUND: Cam morphology, a distinct bony morphology of the hip, is prevalent in many athletes, and a risk factor for hip-related pain and osteoarthritis. Secondary cam morphology, due to existing or previous hip disease (eg, Legg-Calve-Perthes disease), is well-described. Cam morphology not clearly associated with a disease is a challenging concept for clinicians, scientists and patients. We propose this morphology, which likely develops during skeletal maturation as a physiological response to load, should be referred to as primary cam morphology. The aim of this study was to introduce and clarify the concept of primary cam morphology. DESIGN: We conducted a concept analysis of primary cam morphology using articles that reported risk factors associated with primary cam morphology; we excluded articles on secondary cam morphology. The concept analysis method is a rigorous eight-step process designed to clarify complex 'concepts'; the end product is a precise definition that supports the theoretical basis of the chosen concept. RESULTS: We propose five defining attributes of primary cam morphology-tissue type, size, site, shape and ownership-in a new conceptual and operational definition. Primary cam morphology is a cartilage or bony prominence (bump) of varying size at the femoral head-neck junction, which changes the shape of the femoral head from spherical to aspherical. It often occurs in asymptomatic male athletes in both hips. The cartilage or bone alpha angle (calculated from radiographs, CT or MRI) is the most common method to measure cam morphology. We found inconsistent reporting of primary cam morphology taxonomy, terminology, and how the morphology is operationalised. CONCLUSION: We introduce and clarify primary cam morphology, and propose a new conceptual and operational definition. Several elements of the concept of primary cam morphology remain unclear and contested. Experts need to agree on the new taxonomy, terminology and definition that better reflect the primary cam morphology landscape-a bog-standard bump in most athletic hips, and a possible hip disease burden in a selected few.

Clinical outcome of femoral neck system versus cannulated compression screws for fixation of femoral neck fracture in younger patients.

BACKGROUND: The clinical outcome of a new fixation device (femoral neck system, FNS) for femoral neck fractures remains unclear. The main purpose of this study was to evaluate two different internal fixation methods for the treatment of femoral neck fractures in patients aged under 60 years. METHODS: We retrospectively studied patients who underwent internal fixation surgery in our hospital for femoral neck fractures between January 2017 and January 2020. Cannulated compression screws (CCS) and FNS groups were divided according to different internal fixation methods. General data (such as sex, age, body mass index, type of fracture) of all patienFemoral neck shorteningts were collected, and joint function was evaluated using the Harris Hip Score (HHS) before and 1 year after surgery. We recorded related surgical complications, including femoral head necrosis, nonunion, and femoral neck shortening. RESULTS: There were no significant differences in age, sex, or body mass index between the two groups. There was no statistical difference in HHSs between the two groups before surgery. Patients who underwent FNS treatment had longer surgery time (79.75 ± 26.35 min vs. 64.58 ± 18.56 min, p = 0.031) and more blood loss (69.45 ± 50.47 mL vs. 23.71 ± 28.13 mL, p < 0.001). The degree of femoral neck shortening in the FNS group was significantly lower than that in the CCS group (10.0% vs 37.5%, p = 0.036). Regarding postoperative complications, there was no statistical difference in the incidence of femoral head necrosis and fracture nonunion between the two groups. CONCLUSION: Patients younger than 60 with femoral neck fractures can obtain satisfactory clinical results with CCS or FNS treatment. FNS has excellent biomechanical properties and shows significantly higher overall construct stability.

Prevalence and predictive factors of osteoporosis in Thai systemic sclerosis.

Systemic sclerosis (SSc) is recognized as a chronic inflammatory disease and several SSc-associated factors may increase the risk of osteoporosis and its related fractures. To determine the prevalence and predictive factors of osteoporosis in Thai SSc, a cross-sectional study was designed in adult SSc patients at Scleroderma clinic, Khon Kaen University Hospital. The prevalence of osteoporosis with the 95% confidence interval (CI) were determined and the odds ratio (OR) with 95%CI were assessed the clinical association with osteoporosis. A total of 205 SSc patients were recruited with the female to male ratio of 2.7:1. The majority of cases were diffuse SSc subset (83.4%) with a disease duration < 5 years (62.9%). The overall prevalence of osteoporosis was 29.3% (95%CI 23.1-36.0). After an age adjusted analysis, the respective prevalence of osteoporosis at lumbar spine (LS) in women and men was 26.3% and 10%, while the prevalence of osteoporosis at the femoral neck (FN) in women and men was 11% and 2.1%. Low BMI (≤ 18.5 kg/m2) and menopause were associated with osteoporosis at both the LS and FN. Using multivariate analysis, low BMI and menopause were associated with osteoporosis at LS (OR 7.78 and 5.32, respectively), while low BMI was also associated with osteoporosis at LS in pre-menopausal women. In conclusion, the prevalence of osteoporosis in Thai SSc was 29.3%. Osteoporosis at the LS is more common than FN in both men and women. Low BMI was associated with osteoporosis in overall SSc and pre-menopausal women, while only menopause was associated with osteoporosis at the FN.

Accuracy of CT for measuring femoral neck anteversion in children with developmental dislocation of the hip verified using 3D printing technology.

BACKGROUND: Accurate femoral neck anteversion angle (FNA) measurement is of great significance in the diagnosis and treatment of developmental dysplasia of the hip (DDH) in children. The FNA measurement still remains a controversy. We aimed to verify the accuracy of our CT method by 3D printing technology and to evaluate its clinical value. METHODS: Sixty-eight children with unilateral DDH were enrolled, and their FNA was measured using 2D-CT and 3D-CT, respectively, by three observers. This procedure was repeated 3 months later. The above measurement outcomes were then compared with the results in the 3D-printed femur (3D-PF) model. The FNA in the 3D-PF model was measured by three observers (two radiologists and one orthopedist; all were professors) collectively through electronic angle instrument. RESULTS: The primary measurement of FNA at the affected hips by 2D-CT was 44.0 ± 6.1, 49.5 ± 8.9, and 52.8 ± 7.9°, respectively. On the 3D-CT, it was 47.6 ± 5.4, 49.3 ± 6.8, and 48.6 ± 6.2°. Three months later, the FNA on 2D-CT was 49.3 ± 10.5, 42.8 ± 7.4, and 45.1 ± 9.3°, and it was 48.0 ± 6.5, 48.9 ± 7.2, and 49.0 ± 5.7° on 3D-CT, respectively. The FNA in the 3D-PF model at the affected and unaffected hips was 48.5 ± 6.6 and 36.9 ± 13.1°. There were significant differences between 2D-CT and 3D-PF measurements, but no significant difference was found between 3D-CT and 3D-PF measurements. The results by 2D-CT showed significant differences among groups and between the groups. However, the results by 3D-CT had no significant differences among groups or between the groups. CONCLUSION: The results of our study showed that 3D-CT is a more precise, and reproducible method for FNA measurement in DDH. The FNA at the affected hips is 11.6° larger than the unaffected in DDH children aged 3-8 years.

Is Cam Morphology Found in Ancient and Medieval Populations in Addition to Modern Populations?

BACKGROUND: Cam morphology is thought to originate near puberty and reflects a response of the peripheral aspect of the proximal femoral physis to increased local load. Participation in particular sports activities has been associated with cam morphology in contemporary patient populations; however, it is unclear whether cam is a recent phenomenon. There are limited data regarding the frequency of its occurrence and the general deviations in femoral anatomy in different historical populations. Such information may help to understand the possible influence of lifestyle and diet on cam morphology. QUESTIONS/PURPOSES: The purpose of this study was to evaluate femoral morphology in three historical populations. We asked: (1) Was cam morphology present in the three study populations, did those populations differ, and were there differences between sexes? (2) Were there differences in neck-shaft angle, version, or inclination between and among the examined populations? METHODS: We examined 204 adult femurs from the Neolithic population from Iran (n = 37, 3000 BC to 1631 BC), medieval population from Poland (n = 135, 10th to 13th centuries), and contemporary Australian aborigines (n = 32, early 20th century), provided by the Open Research Scan Archive, Museum of the First Piasts at Lednica and the University of Wroclaw, respectively. All three human populations represent different chronologic periods and lifestyles. All bones were scanned using CT and then measured on their three-dimensional (3-D) reconstructions in selected planes. Cam impingement was defined as an alpha angle > 55° measured on the inclination view. To evaluate the differences in anatomy between populations, we measured the true neck-shaft angle on the true AP view, apparent neck-shaft angle on the apparent AP view, the version angle on the version view, and the inclination angle on the inclination view. The prevalence of cam morphology and other anatomic parameters were compared among groups using chi-square test, one-way ANOVA with post hoc Tukey test, and paired t-test. RESULTS: Cam morphology was present in 5% of the Neolithic population from Iran, in 7% of the medieval population from Poland, and 3% of the contemporary Australian aborigine femurs (OR Neolithic population from Iran/the medieval population from Poland 0.7 [95% CI 0.2 to 3.4]; p = 0.67; OR Neolithic population from Iran/contemporary Australian aborigines 1.8 [95% CI 0.2 to 20.5]; p = 0.65; OR the medieval population from Poland/contemporary Australian aborigines 2.5 [95% CI 0.3 to 20.1]; p = 0.40). There were differences in the presence of cam morphology between the sexes in the medieval population from Poland with both femurs (females: 1% [1 of 76]; males: 15% [9 of 59]; p = 0.002). There was a difference in true neck-shaft angle between the Neolithic population from Iran (121° ± 6°) and contemporary Australian aborigines (131° ± 5°; mean difference 10° [95% CI 7° to 13°]; p < 0.001) and between the medieval population from Poland (124° ± 5°) and the contemporary Australian aborigines (mean difference 7° [95% CI 5° to 9°]; p < 0.001). Apparent neck-shaft angle differed between the Neolithic population from Iran (126° ± 6°) and the contemporary Australian aborigines (134° ± 5°; mean difference 8° [95% CI 6° to 11°]; p < 0.001), and between the medieval population from Poland (126° ± 6°) and the contemporary Australian aborigines (mean difference 9° [95% CI 7° to 11°]; p < 0.001). Moreover, we observed a difference in the version angle between the Neolithic population from Iran (19° ± 7°) and the medieval population from Poland (12° ± 9°; mean difference 7° [95% CI 4° to 10°]; p < 0.001] and in the inclination angle between aforementioned groups (18° ± 7° versus 11° ± 8°; mean difference 7° [95% CI 5° to 10°]; p < 0.001). CONCLUSION: This study found that cam morphology existed in historical populations at rates comparable with a contemporary population. CLINICAL RELEVANCE: The presence of cam morphology in historical populations suggests that cam morphology can develop outside of the intense sports activity seen in modern adolescents. Further study will help elucidate the etiology of cam morphology, which may be useful in the development of preventive strategies.

Finite Element Analysis of Femoral Neck Fracture Treated with Bidirectional Compression-Limited Sliding Screw.

BACKGROUND The rate of femoral neck shortening after internal fixation for femoral neck fracture is high and this complication reduces the function of the affected lower limb. The aim of this study was to design a bidirectional compression-limited sliding screw (BCLSC) that can achieve a full balance between retaining the sliding pressure of the ends of and maintaining the length of the femoral neck. MATERIAL AND METHODS We constructed a 3-dimensional model of a Pauwels III femoral neck fracture and models of 3 internal fixation methods (3 cannulated screws [3CS], dynamic hip screw [DHS]+CS, and BCLSC) by finite element analysis (FEA).The finite element model simulated the loading of the human body when standing on 1 leg. Displacement and stress distribution of the models were calculated based on an axial stress of 600 N. RESULTS The peak von Mises stress (VMS) values of fracture ends in the 3CS, DHS+CS and BCLSC groups were 94.687 MPa, 26.375 MPa and 45.698 MPa; the peak VMS values of internal fixed stress were 451.53 MPa, 174.45 MPa, and 337.34 MPa; the peak VMS values of the lateral femoral wall were 70.021 MPa, 53.033 MPa, and 20.009 MPa; maximum displacements of the femoral head were 1.4482 mm, 1.3813 mm, and 1.3889 mm; and the internal fixed displacement peaks were 4.1134 mm, 3.91 mm, and 4.1004 mm, respectively. CONCLUSIONS The FEA showed that compared with the CS, the new BCLSC showed better performance in resisting shearing force for Pauwels III femoral neck fracture, with better mechanical properties. These data provide a basis for further experiments and clinical application.

Subtle Slipped Capital Femoral Epiphysis Is not Associated With Idiopathic Cam Morphology.

BACKGROUND: The etiology of idiopathic cam morphology remains unclear. One theory suggests that subtle slipped capital femoral epiphysis (SCFE) leads to proximal femoral changes resulting in cam morphology. The purpose of this study was to evaluate the association between subtle SCFE and cam morphology in a large osteological collection. METHODS: We examined 962 cadaveric hips to measure 2 markers of cam morphology, alpha angle and anterior femoral head-neck offset (AHNO), and a validated, objective marker of subtle SCFE deformity (calcar ridge line offset). When the femur is viewed medially, the calcar ridge line extends from the lesser trochanter proximally along the postero-inferior femoral neck and points toward the fovea. In SCFE-like deformity, the fovea deviates posteriorly from this projected line. Pearson correlations were performed to evaluate for possible association of calcar ridge line offset with alpha angle and AHNO. In addition, a multiple regression analysis was performed to determine the influence of age, alpha angle, and AHNO on calcar ridge line offset. RESULTS: There was no clinically relevant association between the calcar ridge line offset and alpha angle (r=-0.02, P=0.58) or AHNO (r=0.08, P=0.012). Furthermore, specimens whose calcar ridge line deviated 1 SD above the mean (more SCFE-like deformity) had a smaller alpha angle (46.6±9.1 vs. 48.3±10.6, P=0.046) and greater AHNO (0.83±0.19 vs. 0.77±0.16, P<0.001), both reflecting less cam-like morphology. On regression analysis, increasing age and increasing AHNO (decreased cam morphology) predicted increased calcar ridge line offset, though the model accounted for only 1.2% of the variance. CONCLUSIONS: Subtle SCFE-like deformity, as objectively measured from the calcar ridge line, was not predictive of more cam-like morphology, and in fact mild opposite associations were found. Further study is needed to identify other potential etiologies of idiopathic cam morphology. CLINICAL RELEVANCE: We present evidence from a large, well-documented osteological collection indicating that subtle SCFE is not associated with idiopathic cam morphology.