Prediction of Incident Hip Fracture with the Estimated Femoral Strength by Finite Element Analysis of DXA Scans in the Study of Osteoporotic Fractures

A bone fractures only when loaded beyond its strength. The purpose of this study was to determine the association of femoral strength, as estimated by finite element (FE) analysis of DXA scans, with incident hip fracture in comparison to hip BMD, FRAX(®) and hip structure analysis (HSA) variables. This prospective case-cohort study included a random sample of 1941 women and 668 incident hip fracture cases (295 in the random sample) during a mean±SD follow-up of 12.8±5.7 yrs from the Study of Osteoporotic Fractures (n=7860 community-dwelling women ≥67 yr of age). We analyzed the baseline DXA scans (Holgoic 1000) of the hip using a validated plane-stress, linear-elastic finite element (FE) model of the proximal femur and estimated the femoral strength during a simulated sideways fall. Cox regression accounting for the case-cohort design assessed the association of estimated femoral strength with hip fracture. The age-BMI-adjusted hazard ratio (HR) per SD decrease for estimated strength (2.21, 95% CI 1.95–2.50) was greater than that for TH BMD (1.86, 95% CI 1.67–2.08; p<0.05), FN BMD (2.04, 95% CI 1.79–2.32; p>0.05), FRAX(®) scores (range 1.32–1.68; p<0.0005) and many HSA variables (range 1.13–2.43; p<0.005), and the association was still significant (p<0.05) after further adjustment for hip BMD or FRAX(®) scores. The association of estimated strength with incident hip fracture was strong (Harrell's C index 0.770), significantly better than TH BMD (0.759, p<0.05) and FRAX(®) scores (0.711–0.743, p<0.0001) but not FN BMD (0.762, p>0.05) Similar findings were obtained for intra- and extra-capsular fractures. In conclusion, the estimated femoral strength from FE analysis of DXA scans is an independent predictor and performs at least as well as FN BMD in predicting incident hip fracture in postmenopausal women

Pathogenesis of adolescent idiopathic scoliosis in girls - a double neuro-osseous theory involving disharmony between two nervous systems, somatic and autonomic expressed in the spine and trunk: possible dependency on sympathetic nervous system and hormones with implications for medical therapy

Anthropometric data from three groups of adolescent girls - preoperative adolescent idiopathic scoliosis (AIS), screened for scoliosis and normals were analysed by comparing skeletal data between higher and lower body mass index subsets. Unexpected findings for each of skeletal maturation, asymmetries and overgrowth are not explained by prevailing theories of AIS pathogenesis. A speculative pathogenetic theory for girls is formulated after surveying evidence including: (1) the thoracospinal concept for right thoracic AIS in girls; (2) the new neuroskeletal biology relating the sympathetic nervous system to bone formation/resorption and bone growth; (3) white adipose tissue storing triglycerides and the adiposity hormone leptin which functions as satiety hormone and sentinel of energy balance to the hypothalamus for long-term adiposity; and (4) central leptin resistance in obesity and possibly in healthy females. The new theory states that AIS in girls results from developmental disharmony expressed in spine and trunk between autonomic and somatic nervous systems. The autonomic component of this double neuro-osseous theory for AIS pathogenesis in girls involves selectively increased sensitivity of the hypothalamus to circulating leptin (genetically-determined up-regulation possibly involving inhibitory or sensitizing intracellular molecules, such as SOC3, PTP-1B and SH2B1 respectively), with asymmetry as an adverse response (hormesis); this asymmetry is routed bilaterally via the sympathetic nervous system to the growing axial skeleton where it may initiate the scoliosis deformity (leptin-hypothalamic-sympathetic nervous system concept = LHS concept). In some younger preoperative AIS girls, the hypothalamic up-regulation to circulating leptin also involves the somatotropic (growth hormone/IGF) axis which exaggerates the sympathetically-induced asymmetric skeletal effects and contributes to curve progression, a concept with therapeutic implications. In the somatic nervous system, dysfunction of a postural mechanism involving the CNS body schema fails to control, or may induce, the spinal deformity of AIS in girls (escalator concept). Biomechanical factors affecting ribs and/or vertebrae and spinal cord during growth may localize AIS to the thoracic spine and contribute to sagittal spinal shape alterations. The developmental disharmony in spine and trunk is compounded by any osteopenia, biomechanical spinal growth modulation, disc degeneration and platelet calmodulin dysfunction. Methods for testing the theory are outlined. Implications are discussed for neuroendocrine dysfunctions, osteopontin, sympathoactivation, medical therapy, Rett and Prader-Willi syndromes, infantile idiopathic scoliosis, and human evolution. AIS pathogenesis in girls is predicated on two putative normal mechanisms involved in trunk growth, each acquired in evolution and unique to humans

Outcomes of robotic-arm-assisted medial unicompartmental knee arthroplasty: minimum 3-year follow-up

The purpose of this study was to determine implant survivorship, complications, and re-operation rates, after robotic arm-assisted unicompartmental knee arthroplasty (UKA) at intermediate follow-up. Patient satisfaction and clinical outcome were further investigated, in addition to an analysis of restoration of knee alignment. Fifty-one patients, who received a robotic arm-assisted medial UKA, were prospectively studied, and followed for a minimum of 3 years (mean 51.4 ± 4.5 months). Survival of implants, complications, reoperations, and patients’ overall satisfaction were evaluated. WOMAC scores, as well as knee flexion, varus deformity and flexion contracture were further analyzed, before and after surgery. No implant failure or implant-related complication was recorded, and no revision surgery was performed at the last follow-up in any patient. Overall satisfaction was excellent; 96.1% of patients, at the latest follow-up, was satisfied or very satisfied, while none was dissatisfied or very dissatisfied. Total WOMAC score and each score’s component was significantly improved after surgery. Knee alignment was significantly improved, as flexion increased, varus decreased, and flexion contracture also decreased. In conclusion, robotic-arm-assisted UKA, through accurate implant positioning, significantly improves range of motion and coronal plane alignment, in appropriately selected patients. Excellent overall satisfaction rates and clinical outcomes can be expected, at intermediate follow-up, along with excellent survival of implants and minimal to none surgery-related morbidity. © 2019, Springer-Verlag France SAS, part of Springer Nature

The role of parathyroid hormone (PTH) and vitamin D in falls and hip fracture type

Background: Fragility fractures of the hip are associated with high morbidity and mortality, and represent a rather devastating consequence of osteoporosis. Hip fractures are traditionally investigated as a whole, although it has been recently implied that distinct pathogenic mechanisms may lead either to trochanteric or subcapital fractures. Aims: To investigate whether differences exist by hip fracture type with respect to serum 25(OH)D (vitamin D) and parathyroid hormone (PTH) levels, in addition to epidemiological and demographic data, including history of falls. Methods: The inclusion criteria were met by 116 patients [48 men and 68 women; mean age 80.8 ± 8.5 (range 62–94) years]. Patients were analyzed according to hip fracture type, history of falls, and vitamin D and PTH status. Results: Older age, recurrent falls, serum levels of PTH &gt; 65 pg/ml, and severe vitamin D deficiency were found to be associated with trochanteric fractures. Additionally, older age, female gender, PTH &gt; 65 pg/ml, and severe vitamin D deficiency were related to recurrent falls. Meanwhile, patients with absence of PTH response to low vitamin D levels, were not repeated fallers and suffered mostly from subcapital fractures. Discussion and conclusion: Elevated PTH levels predispose both to falls and trochanteric fractures, while vitamin D-deficient patients with normal PTH levels are mostly related to subcapital fractures. It is thereby indicated that different pathophysiological processes lie behind subcapital and trochanteric fractures. A better understanding of these mechanisms may assist in the development of prevention strategies for individuals recognized at risk for falls and either type of hip fracture. © 2019, Springer Nature Switzerland AG

Serum vitamin D levels and muscle strength in ambulatory elderly men and women and in patients with hip fracture in Crete

The importance of vitamin D in calcium and phosphate homeostasis and in bone metabolism and also the harmful effects of its deficiency in skeletal health in infancy (rickets) as well as in adult life (osteomalacia – osteoporosis) is well known. Less known is the role of vitamin D in the function of the muscles and the effect of its deficiency on muscle strength and falling which often results in hip fracture. Epidemiologic studies have shown that vitamin D deficiency is common among the elderly especially in home bound or institutionalized subjects and also in patients with hip fractures. It has been referred that great and chronic vitamin D deficiency cause muscle weakness due to a direct effect through vitamin D receptors on the maturation and functioning of the muscle cells resulting in increased incidence of falls and hip fractures. Studies in European countries have also shown that cervical hip fractures occur more often than trochanteric ones in countries of northern Europe whereas the opposite is true in southern Europe and Mediterranean countries where were also found the lowest in Europe 25 (OH) D serum levels among the elderly. Aims of this study were to investigate 1) the 25 (OH) D serum levels in ambulatory community dwelling elderly Cretan men and women 2) the possible correlation between serum 25 (OH) D levels and quadriceps muscle strength in the same population and 3) the possible correlation of 25 (OH) D serum levels with the type of hip fracture between elderly patients with cervical and trochanteric hip fractures In the first part of this study, were measured the serum values of 25 (OH) D in 101 ambulatory community dwelling subjects, 70 women and 31 men, 65 years of age or over recruited from centers of open care for the aged of the Municipality of Heraklion-Crete following strict inclusion criteria. Body mass index (BMI), kg/m2, grade of mobility, type of daily diet used, number of falls during the preceding year, type of clothing used and time of exposure to sunlight were recorded. The serum values of 25 (OH) D were measured using the OCTEIA 25 (OH) D kit. Ref. values 44-144 nmol/l and of parathormone (PTH) using the immunoradiometric assay ELSA-PTH CIS Bio-international. Ref. values 15-65 pg/ml. Serum creatinine, calcium and phosphate serum levels were measured using standard methods, from fasting blood samples. 1) The mean serum 25 (OH) D level was found to be 51,46 ± 27,32 nmol/l in women and 71,7 ± 28,65 in men. 2) A percentage of 35,4 of the men and 53,6% of the women had 25 (OH) D serum levels 30 nmol/l. The high proportion of the study participants with vitamin D deficiency should be attributed to: 1) the limited exposure of the study subjects to sunlight due to local clothing habits 2) the limited time spent in outdoors physical activity and 3) to the fact that they did not consume foods fortified with vitamin D. ...............Είναι γνωστός ο ρόλος της βιταμίνης D στην ομοιόσταση του ασβεστίου και του φωσφόρου, καθώς και οι συνέπειες της ανεπάρκειάς της στον οργανισμό του ανθρώπου και ιδιαίτερα στον σκελετό των παιδιών (ραχίτις), αλλά και των ενηλίκων (οστεομαλακία- οστεοπόρωση). Λιγότερο γνωστή είναι η σημασία της βιταμίνης D στην λειτουργία του μυϊκού συστήματος και η σχέση της ανεπάρκειάς της με την ελάττωση της μυϊκής ισχύος και τις πτώσεις, οι οποίες συχνά προκαλούν κατάγματα ισχίου στους ηλικιωμένους. Επιδημιολογικές έρευνες έχουν δείξει ότι η ανεπάρκεια της βιταμίνης D είναι συχνή στους ηλικιωμένους, ιδιαίτερα σε αυτούς που μένουν μόνιμα μέσα στο σπίτι ή σε ιδρύματα, καθώς και στους ασθενείς με κάταγμα ισχίου. Έχει διαπιστωθεί ότι η έντονη και χρόνια ανεπάρκεια της βιταμίνης D οδηγεί σε ελάττωση της μυϊκής ισχύος, λόγω επηρεασμού της ωρίμανσης και λειτουργίας των μυϊκών κυττάρων με αποτέλεσμα την αύξηση της συχνότητας των πτώσεων και των καταγμάτων - ιδιαίτερα του ισχίου – που προκαλούνται από αυτές. Έρευνες σε ευρωπαϊκές χώρες έχουν δείξει επίσης ότι τα αυχενικά κατάγματα του ισχίου είναι συχνότερα από τα διατροχαντήρια στις χώρες της βόρειας Ευρώπης, ενώ το αντίθετο συμβαίνει στις χώρες της νότιας Ευρώπης και της Μεσογείου, όπου έχουν επίσης βρεθεί τα χαμηλότερα επίπεδα 25 (ΟΗ) D στον ορό μεταξύ των ηλικιωμένων κατοίκων των χωρών της Ευρώπης. Σκοποί αυτής της εργασίας ήταν η διερεύνηση των επιπέδων της 25 (ΟΗ) D στον ορό ηλικιωμένων περιπατητικών κατοίκων της Κρήτης, της σχέσης των επιπέδων αυτών με την ισχύ του τετρακέφαλου μυός καθώς και της πιθανής τους σχέσης με τον τύπο του κατάγματος ισχίου ( αυχενικό vs διατροχαντήριο κάταγμα ισχίου ) Στο πρώτο τμήμα της έρευνας, μετρήθηκαν τα επίπεδα της 25 (ΟΗ) D στον ορό σε 101 περιπατητικά άτομα, 70 γυναίκες και 31 άντρες, ηλικίας 65 ετών και άνω, οι οποίοι επιλέχθηκαν από τα ΚΑΠΗ Ηρακλείου Κρήτης, με αυστηρά κριτήρια συμμετοχής. Μετρήθηκαν ο δείκτης σωματικής μάζας (ΒΜΙ, kg/m2), ο βαθμός κινητικότητας, ο τύπος της καθημερινής δίαιτας, ο αριθμός των πτώσεων το προηγούμενο έτος, ο τύπος των ενδυμάτων και ο χρόνος έκθεσης στο ηλιακό φως. Μετρήθηκαν επίσης οι τιμές της 25 (ΟΗ) D στον ορό με τη χρήση της μεθόδου OCTEIA 25 (OH) D με τιμές αναφοράς 48-144 nmol/l και της παραθορμόνης (PTH) με τη χρήση της ανοσοραδιομετρικής μεθόδου ELSA PTH, με τιμές αναφοράς 15-65 pg/ml. 1. Η μέση τιμή της 25 (ΟΗ) D στον ορό ήταν 51,46 ± 27,32 nmol/l στις γυναίκες και 71,7 ± 28,65 στους άνδρες. 2. Το 35,4% των ανδρών και το 51,4% των γυναικών είχαν 25 (ΟΗ) D στον ορό 30 nmol/l. Το υψηλό ποσοστό των συμμετεχόντων στην έρευνα, ιδιαίτερα των γυναικών, με ανεπάρκεια βιταμίνης D θα πρέπει να αποδοθεί 1) στην περιορισμένη έκθεση στο ηλιακό φως, λόγω της χρήσης ενδυμάτων που κάλυπταν όλο το σώμα εκτός του προσώπου, από τον Οκτώβριο μέχρι τον Μάιο 2) στη διάθεση περιορισμένου χρόνου για την εκτός οικίας φυσική δραστηριότητα και 3) στη μη χρήση τροφίμων εμπλουτισμένων με βιταμίνη D. ........................