Hip geometry in hip fracture patients in Greenland occurring over a 7.7-year period

Background Hip geometry influences hip fracture risk. Hip fractures are common, and they are associated with pain, disability, premature death and marked costs on society. Osteoporotic fractures are frequent in Arctic populations and increase with advancing age in this society with a steep rise in life expectancy. Greenland Inuit is a distinct ethnic group, and data on hip geometry is missing. We thus aimed to describe hip geometry in 7.7 years of consecutive hip fracture patients in Greenland. Methods We evaluated collodiaphysial angle, femoral neck length, the outer and inner diameter of the femur at 2 and 5 centimetres below the centre of the lesser trochanter and the cortical thickness from pelvic and hip radiographs in all patients operated in Greenland over 7.7 years. We included all 84 patients with one non-fractured hip visible for geometric analysis. Analyses were conducted in duplicate. Results We found a collodiaphysial angle of 134.8/132.6o in men/women (p = 0.06) and a femoral neck length of 38.0/33.9 mm in men/women (p = 0.001). Cortical thickness was affected by sex in the adjusted analysis (p < 0.001). Cortical thickness index at 5 cm below the centre of the lesser trochanter decreased with age (p = 0.026) and may be influenced by height (2 cm below the centre of the lesser trochanter, p = 0.053). Conclusion Our findings differed from European data and suggest a delicate balance in hip geometry in Arctic populations. Ethnic peculiarities influence the structure of the hip and may influence fracture risk. A focus on hip geometry and risk factors for osteoporotic fractures in Arctic populations is warranted.

Hip Geometry Variation in Homozygous Ectonucleotide Pyrophosphatase/ Phosphodiesterase 1 (ENPP1) Deficient Patients

ENPP1 is an important regulator of skeletal and soft tissue mineralization. Mouse models have demonstrated a link between defective ENPP1 and altered bone mineralization, including osteopenia and mild osteomalacia. In humans, rare homozygous loss of ENPP1 leads to generalized arterial calcification of infancy (GACI), characterized by vascular, joint, and organ calcification, hypophosphatemic rickets/osteomalacia, and skin and retinal findings. Heterozygous ENPP1 deficiency has been described in early-onset osteoporosis and an ENPP1 polymorphism was found to be strongly associated with variation in hip geometry, as measured by DXA hip structural analysis (HSA). However, the overall skeletal phenotype of ENPP1-deficiency is not well characterized in affected individuals. In addition to bone density, DXA provides surrogate information about mechanical strength, resistance to compression, tension, and buckling, offering a non-invasive and clinically accessible tool to assess hip geometry. Parameters include cross-sectional area (CSA), cross-sectional moment of inertia (CSMI), subperiosteal width (SPW), endocortical width (ECW), cortical thickness (CT), section modulus (Z), and buckling ratio (BR)—each measured in the narrow neck (NN), intertrochanteric (IT), and femoral shaft (FS) regions. SPW and ECW increase with age and are correlated with bone fragility. In mice, CSA and CSMI are inversely correlated with bone fragility when assessed by biomechanical tests. However, the opposite correlation has been observed in patients with fractures. HSA by DXA was assessed in 7 homozygous ENPP1-deficient patients (age range 5–56 years) and in 73 sex- and age-matched controls. All ENPP1-deficient patients were hypophosphatemic, of which, 2 were receiving treatment. Given the small sample size, standardized test statistics (t-scores) were derived for 21 hip geometry parameters; comparisons between groups were performed using the Mann-Whitney test. The Benjamini-Hochberg test was used to correct for multiple comparisons with a false discovery rate (FDR) q-value threshold set at 0.15. Compared with controls, ENPP1-deficient patients had significant changes in structural and derived measures of strength. Increases were seen in NN SPW, NN ECW, and FS SPW, which are correlated with bone fragility. In contrast, the increases seen in FS CSA, FS Z, FS CSMI, and NN CSMI are associated with improved bone strength. Although a q-value threshold of 0.15 indicates that 15% (~1/7) of all significant discoveries will represent a false positive, most findings represented true discoveries. These findings suggest that ENPP1 influences bone structure and strength, supporting findings from the aforementioned ENPP1 polymorphism study describing increased SPW in the NN and FS regions. This work contributes to the nascent body of literature studying the impact of ENPP1 on skeletal homeostasis.

Effect of Tissue-Selective Estrogen Complex on Hip Structural Geometry in Postmenopausal Women: A 12-Month Study

BackgroundHip structural analysis (HSA) is a method for evaluating bone geometry reflecting bone structural and biomechanical properties. However, tissue-selective estrogen complex (TSEC) treatment effects on HSA have not been investigated.ObjectiveThis study was performed to evaluate the effect of TSEC treatment on hip geometry in postmenopausal Korean women. The treatment was given for 12 months, and hip geometry was measured by HSA.Materials and MethodsA total of 40 postmenopausal women who received TSEC containing conjugated estrogen 0.45 mg and bazedoxifene 20 mg for treating vasomotor symptoms were included in this retrospective cohort study. The changes in bone mineral density and parameters of HSA including the outer diameter, cross-sectional area, cross-sectional moment of inertia, cortical thickness, section modulus, and buckling ratio as determined by dual-energy X-ray absorptiometry were compared before and after 12 months of TSEC treatment.ResultsMean age and years since menopause were 55.1 and 4.5 years, respectively. Total hip bone mineral density significantly increased by 0.74% after treatment (P=0.011). The changes in HSA were mainly demonstrated in the narrow femoral neck: cross-sectional area (P=0.003) and cortical thickness (P&lt;0.001) increased significantly. For the shaft region, only SM decreased significantly after treatment (P=0.009). However, most parameters did not change significantly with TSEC treatment in the intertrochanteric and shaft regions.ConclusionsOur findings demonstrate that 12 months of TSEC treatment could improve bone geometry as measured by HSA. The findings suggest that TSEC might be an interesting option for the prevention of fracture as well as osteoporosis in postmenopausal women.

Restoration of the hip geometry after two-stage exchange with intermediate resection arthroplasty for periprosthetic joint infection

Two-stage exchange with intermediate resection arthroplasty (RA) is a well-established surgical procedure in the treatment of chronic periprosthetic joint infection (PJI), whereby a higher failure rate of final hip geometry restoration due to tissue contraction is controversially discussed. The aim was to evaluate radiographic changes of hip geometry parameters during PJI treatment and to determine the impact of the intermediate RA on the final joint restoration after reimplantation of a total hip arthroplasty (reTHA). Radiographic parameters (leg length (LL), femoral offset (FO), horizontal/vertical acetabular center of rotation distance (h/vCORD)) of 47 patients (mean age: 64.1 years) were measured on standard radiographs of the pelvis and compared between four different stages during PJI treatment (pre-replacement status (preTHA), primary total hip arthroplasty (pTHA), RA and reTHA). The RA duration (mean: 10.9 months) and the number of reoperations during this period (mean: n = 2.0) as well as their impact on hip geometry restoration were evaluated. Between preTHA and pTHA/reTHA an equivalent restoration was measured regarding the FO (p < 0.001/p < 0.001) and hCORD (p = 0.016/p < 0.001), but not regarding the LL and vCORD. In contrast, analysis revealed no influence of RA and an equivalent reconstruction of LL (p = 0.003), FO (p < 0.001), v/hCORD (p = 0.039/p = 0.035) at reTHA compared to pTHA. Furthermore, RA duration (p = 0.053) and the number of reoperations after RA (p = 0.134) had no impact on radiographic hip geometry restoration. The two-stage exchange with intermediate RA does not alter the preexisting hip joint parameters, whereby a good restoration of the final hip geometry, independent of the duration or the number of reoperations, can be achieved.

Hip Geometry in Hip Fracture Patients in Greenland

Background: Hip geometry influences hip fracture risk. Hip fractures are common and they are associated with pain, disability, premature death and marked costs on society. Osteoporotic fractures are frequent in Arctic populations and increase with advancing age in this society that has a steep rise in life expectancy. Greenland Inuit is a distinct ethnic group and data on hip geometry is missing. This let us to describe hip geometry in populations with hip fracture in Greenland.Methods: We evaluated collodiaphysial angle, femoral neck length, the outer and inner diameter of the femur at 2 and 5 centimetres below the centre of the lesser trochanter and the cortical thickness from pelvic and hip radiographs in all patients operated in Greenland over a 7.7-year period. We included all 84 patients with one non-fractured hip visible for geometric analysis. Analyses were conducted in duplicate.Results: We found collodiaphysial angle of 134.8/132.6o in men/women (p=0.06) and femoral neck length of 38.0/33.9mm in men/women (p=0.001). Cortical thickness was influenced by sex in the adjusted analysis (p<0.001). Cortical thickness index at 5cm below the centre of the lesser trochanter decreased with age (p=0.026) and may be influenced by height (2cm below the centre of the lesser trochanter, p=0.053). Conclusion: Our findings differed from European reference data and suggest a delicate balance in hip geometry that may change with lifestyle transition in Arctic populations. Ethnic peculiarities influence the hip structure and may have an impact on fracture risk. A focus on hip geometry and risk factors for osteoporotic fractures in Arctic populations is warranted.

Association of HIVEP3 Gene and Lnc RNA with Femoral Neck Bone Mineral Content and Hip Geometry by Genome-Wide Association Analysis in Chinese People

Purpose. GWAS has successfully located and analyzed the pathogenic genes of osteoporosis. Genetic studies have found that heritability of BMD is 50%–85% while the other half is caused by hip geometric parameters and tissue horizontal characteristics. This study was designed to study the GWAS of osteoporosis in Shanghai Han population. Methods. We collected 1224 unrelated healthy young men (20–40 years old), young women (20–40 years old), and postmenopausal women (over 50 years old) who lived in Shanghai. BMD and hip geometric parameters were measured by dual-energy X-ray absorptiometry. The genomic DNA of peripheral blood was extracted and analyzed by using Illumina Human Asian Screening Array-24 + v 1.0 (ASA) gene chip. Statistical analysis was carried out to evaluate the relationship between these SNPs and BMD and hip geometric parameters. Results. A total of 1155 subjects were included. We found that one SNP rs35282355 located in the human immunodeficiency virus type 1 enhancer-binding protein 3 gene (HIVEP3) and another 25 SNPs located in LINC RNA were significantly correlated with bone mineral content (BMC) in the femoral neck ( P = 2.30 × 10−9, P < 5 × 10−8). We also found that the correlation between SNP rs35282355 and cross-sectional area (CSA) of hip geometry was a significant marginal statistical difference ( P = 5.95 × 10−8). Conclusions. Through this study, we found that HIVEP3 gene and LINC RNA are potentially correlated with femoral neck BMC. These results provide important information for us to further understand the etiology and genetic pathogenesis of osteoporosis. In the future, we will expand the sample size to verify these loci and carry out molecular research.

TO EVALUATE EFFECT OF HORIZONTAL HIP OFFSET AND LEG LENGTH RECONSTRUCTION ON FUNCTIONAL OUTCOME OF TOTAL HIP REPLACEMENT

Background: For total hip replacement besides long term durability a optimal postoperative functional outcome is essential.so aim of this study was to determine the combined influence of hip geometry reconstruction on the clinical outcome following primary total hip replacement for unilateral osteoarthritis. Methods: A hospital based prospective study was carried out on 60 cases of unilateral osteoarthritis with normal contralateral hip. We prospectively assessed the clinical outcome and radiographic parameters for hip geometry reconstruction using validated measurements for the operated hip compared to the contralateral native hip with primary unilateral THA. The correlation of reconstruction parameters was investigated using a multivariate polynomial regression model for the dependent variable ?HHS (difference between the Harris hip scores preoperatively and 6 months postoperatively). Target zones for hip reconstruction were investigated for an association with superior clinical outcome. Results: The regression model demonstrated a significant correlation for the ?HHS and both hip offset (HO) reconstruction and leg length difference. Patients with accurate to slightly increased HO reconstruction combined with balanced leg length demonstrated a significantly higher ?HHS than patients outside this zone. Conclusion: HO and leg length reconstruction demonstrated an additive effect on clinical outcome and surgeons should aim for high accuracy in the reconstruction of both factor. Keyword: Hip offset, total hip arthoplasty, harris hip score