Search

Background: Debate exists on the optimum fixation construct for large avulsion fractures of the fifth metatarsal base. We compared the biomechanical strength of 2 headless compression screws vs a hook plate for fixation of these fractures., Methods: Large avulsion fractures were simulated on 10 matched pairs of fresh-frozen cadaveric specimens. Specimens were assigned to receive two 2.5-mm headless compression screws or an anatomic fifth metatarsal hook plate, then cyclically loaded through the plantar fascia and metatarsal base. Specimens underwent 100 cycles at 50%, 75%, and 100% physiological load for a total of 300 cycles., Results: The hook plate group demonstrated a significantly higher number of cycles to failure compared with the screw group (270.7 ± 66.0 [range 100-300] cycles vs 178.6 ± 95.7 [range 24-300] cycles, respectively; P = .039). Seven of 10 hook plate specimens remained intact at the maximum 300 cycles compared with 2 of 10 screw specimens. Nine of 10 plate specimens survived at least 1 cycle at 100% physiologic load compared with 5 of 10 screw specimens., Conclusion: A hook plate construct was biomechanically superior to a headless compression screw construct for fixation of large avulsion fractures of the fifth metatarsal base., Clinical Relevance: Whether using hook plates or headless compression screws, surgeons should consider protecting patient weight-bearing after fixation of fifth metatarsal base large avulsion fracture until bony union has occurred.

Skeletal ossification occurs either directly within mesenchymal tissues or indirectly through a template of hyaline cartilage. Between the epiphyses and diaphyses of long bones, hyaline cartilaginous growth plates remain and constitute the progenitor cell reservoir from which the tissue develops toward the diaphysis and determines longitudinal bone size. Growth plates exhibit a characteristic architecture with columnar cell organization and different zonal morphology. The cells increase their volume toward the diaphysis, and eventually the longitudinally arranged septa of extracellular matrix mineralize. Finally, the mineralized cartilage matrix is replaced by lamellar bone. The extracellular matrix is rich in glycosaminoglycans, proteoglycans, and collagen II; at the edges of the growth plates, collagen I, III, and collagen X, especially at the mineralization front, are also present.The geometry of the growth plates is regulated by the local mechanical environment. In general, all plates orient themselves perpendicular to the resulting compressive force vector; grooves, ridges, and lateral angulations are adaptations to withstand shear forces acting on the growth plates. The final shape of the fully grown bone is determined not only by the epiphyseal growth plates but also by their apophyseal counterpart. Both structures respond in a comparable fashion to the local mechanical environment., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

The basic law of mechanobiology states that the external form and internal architecture of the skeleton and joints follow the functional stimuli that act upon them. Radiographs and magnetic resonance imaging reflect the loading history of the growing child, enabling an experienced radiologist to analyze the clinical functioning of patients by interpreting imaging studies. Concerning the hip joint, the physes of the coxal femoral end, the coxal femoral epiphysis with its epiphyseal growth plate, as well as the apophysis of the greater trochanter with its trochanteric growth plate, are the essential organ structures subject to internal forces. They determine the definitive geometric shape of the proximal femur. Indirectly they influence the appearance of the acetabulum and the centration of the hip joint., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

The study of skeletochronology and bone tissue as a record of information on ontogenetic stages and events is widely used for improving the knowledge about life histories (LHs) of extinct and extant vertebrates. Compared with dinosaurs and extant reptiles, mammalian bone histology has received little attention. Here, we calibrate for the first time bone and dental age with histological bone characteristics and LH stages in ontogenetic series of red deer. We rely on known LHs of different aged individuals of captive Cervus elaphus hippelaphus from Austria to correlate epiphyseal closure, dental eruption pattern, bone growth marks and bone tissue patterns in femora and tibiae, and of wild Cervus elaphus hispanicus from Spain. Our data show that females (of both subspecies) attain skeletal maturity earlier than males. At this moment, epiphyseal closure (in femora and tibiae) and dental eruption are complete and long bones start to deposit an external fundamental system. The results also show that the attainment of reproductive maturity in red deer occurs slightly before skeletal maturity., (© 2019 Anatomical Society.)

Epiphyseal tubercle and peripheral cupping can influence the development of slipped capital femoral epiphysis (SCFE) and Cam morphology. During normal skeletal growth, epiphyseal tubercle shrinks while the peripheral cupping grows. We hypothesized that epiphyseal tubercle act as the primary stabilizer of the head-neck junction at early stages and this role is gradually transferred to epiphyseal cupping as the tubercle shrinks and cupping grows. From a cohort of 80 boys and girls (8-15 years old) with normal hips, CT scans of 5 subjects corresponding to minimum, 25th percentile, median, 75th percentile and maximum relative tubercle and cupping height were used to develop 3D finite element models. In vivo measured hip loads were used to study load sharing between the tubercle and peripheral cupping under combined and uniaxial loads exerted on femoral head during a range of daily activities. Lower epiphyseal tubercle height, larger epiphyseal cupping height and bigger differences in tubercle and cupping heights were strongly associated with increased epiphyseal cupping to epiphyseal tubercle stress ratios (R 2  > 0.7). We found lower peripheral cupping stresses relative to the tubercle (cupping to tubercle stress ratio <1) in hips with larger tubercle and smaller cupping. The relative decreases in tubercle size along with increased in peripheral cupping in our models gradually shifted the load distribution to higher stresses in the periphery compared to the epiphyseal tubercle area (cupping to tubercle stress ratio >1). Both tubercle and cupping play a substantial role in sharing the generated stresses across the head-neck junction under all tested loading conditions. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1571-1579, 2019., (© 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

Background: Medial patellofemoral ligament (MPFL) reconstruction is associated with a high rate of complications, including recurrent instability and persistent knee pain. Technical errors are among the primary causes of these complications. Understanding the effect of adjusting patellofemoral attachments on length change patterns may help surgeons to optimize graft placement during MPFL reconstruction and to reduce graft failure rates., Purpose: To determine the in vivo length changes of the MPFL during dynamic, weightbearing motion and to map the isometry of the 3-dimensional wrapping paths from various attachments on the medial femoral epicondyle to the patella., Study Design: Descriptive laboratory study., Methods: Fifteen healthy participants were studied with a combined computed tomography and biplane fluoroscopic imaging technique during a lunge motion (full extension to ~110° of flexion). On the medial femoral epicondyle, 185 attachments were projected, including the anatomic MPFL footprint, which was divided into 5 attachments (central, proximal, distal, posterior, and anterior). The patellar MPFL area was divided into 3 possible attachments (proximal, central, and distal). The length changes of the shortest 3-dimensional wrapping paths of the various patellofemoral combinations were subsequently measured and mapped., Results: For the 3 patellar attachments, the most isometric attachment, with an approximate 4% length change, was located posterior and proximal to the anatomic femoral MPFL attachment, close to the adductor tubercle. Attachments proximal and anterior to the isometric area resulted in increasing lengths with increasing knee flexion, whereas distal and posterior attachments caused decreasing lengths with increasing knee flexion. The anatomic MPFL was tightest in extension, decreased in length until approximately 30° of flexion, and then stayed near isometric for the remainder of the motion. Changing both the femoral and patellar attachments significantly affected the length changes of the anatomic MPFL ( P < .001 for both)., Conclusion: The most isometric location for MPFL reconstruction was posterior and proximal to the anatomic femoral MPFL attachment. The anatomic MPFL is a dynamic, anisometric structure that was tight in extension and early flexion and near isometric beyond 30° of flexion., Clinical Relevance: Proximal and anterior MPFL tunnel positioning should be avoided, and the importance of anatomic MPFL reconstruction is underscored with the results found in this study.

Purpose: Surgeons mainly consider the anterior anatomy of the distal femur in the treatment of patellar instability (PI) with trochlear dysplasia (TD). Through this research, the idea was to analyse the posterior femoral condyle length in TD. The research team posited the presence of morphological differences in the posterior part of the femoral epiphysis in TD compared to a control group. They also postulated that the posterior bicondylar angle (PCA), in the axial plane, was increased in TD., Methods: This is a single-centre morphological study of 100 patients who had a computed tomography (CT) using the same protocol. 50 patients with PI (25 dysplasias A and 25 B-C-D according to the Dejour classification), and 50 controls were included. All patients presenting a clinical PI were considered for the study. None of these patients had undergone a surgical treatment prior to imaging. Demographic characteristics, BMI, and laterality were comparable in all patients. 20 pilot CT scans were used to establish the methodology. The following measurements were performed: anterior bicondylar angle, PCA, and condylar lengths with respect to the surgical transepicondylar axis. Ratios were calculated in relation to the femoral width. TD was classified according to the Dejour classification in grade A or grades B-C-D. An analysis of variance and a linear model were performed within some groups to investigate which parameters correlated with the classification's grade., Results: This study showed a link between TD and the PCA: control group (1.4 ± 0.2°), type A group (1.6 ± 0.3°), and types B, C, D group (2.6 ± 0.3°) (p = 0.01). The difference between the control group and types B, C, D TD group was significant (p = 0.002). In groups B, C, D, the PCA was more important, which proves that in these groups the posterior part of the lateral condyle was relatively shorter compared to the medial condyle. The greater the dysplasia, the longer the medial condyle was in the anterior posterior (p = 0.02)., Conclusions: This study shows not only an anterior but also a posterior anomaly in PI with TD. There is a correlation between the severity of the anterior deformation and the PCA: in other words, the knee is placed in valgus in flexure which promotes the external dislocation of the patella. This anatomical study could open a field of research on the development of surgical treatments based on the correction of posterior condylar femoral anomalies in PI., Level of Evidence: III.

This study has been undertaken in order to describe the bone mass distribution of the dry human radius via dual x-ray absorptiometry (DXA) with a Norland XR-800 densitometer machine. A sample of 39 dry radius bones was used. Two projections were made: antero-posterior and lateral, and five regions of interest were selected. The bone densities and the bone mineral contents of the various regions of the radius in the two projections were compared using Student's t tests for paired samples, with statistically significant differences being found in all of the values, except in the proximal extremity (P Ext). The area of greatest bone mineral content (BMC) was the medial diaphysis (M Diaph), followed by the distal extremity (D Ext), with the lowest value being found in the proximal extremity (P Ext). As for bone mineral density (BMD), a great symmetry is observed if we take the mean point of the longitudinal axis as a reference, with it being distributed from highest to lowest from the central part to the extremities. A correlation study of the BMD and BMC values between the segments themselves and with the total, in both positions, provides us with a high correlation (p ≤ 0.01), with the highest correlation value being found for the proximal diaphysis (P Diaph) region, indicating the heterogeneous nature of the distribution of the radius bone mass. Bone densitometry via DXA is useful in order to establish an overview of the structural construction of the human radius.

Objectives: Several studies have investigated potential functional signals in the trabecular structure of the primate proximal humerus but with varied success. Here, we apply for the first time a "whole-epiphyses" approach to analysing trabecular bone in the humeral head with the aim of providing a more holistic interpretation of trabecular variation in relation to habitual locomotor or manipulative behaviors in several extant primates and Australopithecus africanus., Materials and Methods: We use a "whole-epiphysis" methodology in comparison to the traditional volume of interest (VOI) approach to investigate variation in trabecular structure and joint loading in the proximal humerus of extant hominoids, Ateles and A. africanus (StW 328)., Results: There are important differences in the quantification of trabecular parameters using a "whole-epiphysis" versus a VOI-based approach. Variation in trabecular structure across knuckle-walking African apes, suspensory taxa, and modern humans was generally consistent with predictions of load magnitude and inferred joint posture during habitual behaviors. Higher relative trabecular bone volume and more isotropic trabeculae in StW 328 suggest A. africanus may have still used its forelimbs for arboreal locomotion., Discussion: A whole-epiphysis approach to analysing trabecular structure of the proximal humerus can help distinguish functional signals of joint loading across extant primates and can provide novel insight into habitual behaviors of fossil hominins., (© 2018 Wiley Periodicals, Inc.)

Medicolegal physicians are increasingly called upon to aid in determining the administrative age group affiliation of refugees with questionable unaccompanied minor claims. According to guidelines for forensic age assessment, age differentiation along the 18-year-old cut-off relies on clavicular ossification. The thin-slice computed tomography scan (TSCTs) of the medial clavicular epiphysis (MCE) is one of the methods contributing to this assessment, though it is not yet universally accepted. The aim of this systematic review was to identify scientific papers where age was assessed using TSCTs of the MCE and to observe whether this examination was reproducible and reliable in estimating a person's age relative to the 18-year-old threshold. A search algorithm was applied to several databases to identify articles in accordance with the PRISMA (Preferred Reporting Items for Systematic-Reviews and Meta-Analyses) statement. One boxplot per article was constructed, separating by stage of maturation and sex. The 13 articles selected represented a sample of 5605 individuals (3396 males, 2209 females) aged 10 to 35 years. All individuals classified as stages 4 and 5 were aged 18 years or older. The same result was obtained concerning stage 3c, except in one article. The results thus appear reliable and reproducible, in particular, with respect to the 18-year-old threshold; medicolegal physicians should be able to estimate that all individuals in stages 4 and 5 are at least 18 years old. Additional studies applied to several other populations in the world should complement the selected studies.

Background: The new simplified thumb ossification composite index (TOCI) based on ossification of the thumb epiphyses and adductor sesamoid has demonstrated simplicity, excellent reliability, and high accuracy for predicting skeletal maturity, comparable with the Sanders simplified skeletal maturity system (SSMS). It was our belief that, because the terminology of the SSMS system has been commonly used for skeletal maturity prediction in idiopathic scoliosis in publications over the past decade, the clinical applicability of the TOCI system would increase if the stages in the 2 systems were found to be interchangeable and highly correlated., Methods: Hand radiographs of 125 premenarchal girls with newly diagnosed adolescent idiopathic scoliosis who had been followed longitudinally until skeletal maturity were all scored with use of the Tanner-Whitehouse III (TW3) system (stages E through I), the TOCI, and the SSMS. The scores for the epiphyses of the ulnar 4 digits were compared with those for the thumb and correlated with the timing of peak height velocity. Correlations were analyzed with the chi-square test and Cramer V and Somers delta correlations., Results: Six hundred and forty-five hand radiographs (an average of 5 for each girl with idiopathic scoliosis) and 11,517 epiphyses were scored. The rate of concordance between TW3 stages F, G, and I for the thumb proximal phalangeal epiphysis and those for all of the epiphyses of the ulnar 4 digits were 72.5%, 72.5%, and 89.9%, respectively. The overall concordance rate (including all epiphyses) was 71.3%, with a very high Cramer V correlation and significance (p < 0.01). High interchangeability was demonstrated for the TOCI and SSMS stages, supported by a high Somers delta correlation (>0.8) with significance (p < 0.05)., Conclusions: The TOCI is highly practical for clinical use, and its stages are highly interchangeable with those of the SSMS., Clinical Relevance: The TOCI could serve as a simplified "marker" of skeletal maturity on hand radiographs and minimize the learning-curve problems associated with the SSMS in a busy clinical practice.

We investigated talus and tibial plafond subchondral bone puncture strength based on surface location. Puncture tests of the subchondral bone were performed in 9 equal zones on the articular surface of 12 cadaver specimens aged 49.1 years (range, 36-56 years). Compressive load was applied through a microfracture awl at 2 mm/min. Puncture strength was defined as the first load drop in load-deflection curves. In the talus, zone 1 (215 ± 91 N) and zone 2, the anterior medial and anterior middle zones, had significantly greater puncture strength than zones 7, 8, and 9, the posterior medial, middle, and lateral zones (104 ± 43 N, 115 ± 43 N, and 102 ± 35 N, respectively; P < .001). In the tibial plafond, zone 3, the anterior-lateral zone, and zone 7, the posterior medial zone, had significantly greater strength than zone 8, the posterior middle zone (202 ± 72 N, 206 ± 121 N, and 112 ± 65 N, respectively; P < .001) These results suggest that the subchondral bone is significantly weaker to penetrative force in the posterior region than in the anterior region of the talar dome and of the tibial plafond. These findings may have implications for microfracture awl design and for understanding the complex anatomy and physiology of the ankle joint., Levels of Evidence: Controlled laboratory study.

The disk of hyaline cartilage that is interposed between the epiphysis and the metaphysis of each of the long bones is responsible for its elongation, and, thus, when the lower limbs are concerned, for increases in bodily height. This so-called growth plate is avascular, aneural, and alymphatic. It consists solely of chondrocytes and an extracellular matrix which the cells elaborate. The growth plate is architectonically striking in so far as the chondrocytes are aligned in strictly vertical columns, which represent the functional units of longitudinal bone growth. The growth process begins with the slow division of chondrocytes in the resting ("stem cell") zone and proceeds with their rapid proliferation in the adjacent zone. These cells then undergo a process of progressive enlargement, which culminates in the zone of terminal hypertrophy. The life history of any given cell is recapitulated in a vertical column. The neoformation of cartilage in the axial direction is synchronized with its destruction at the vascular invasion front of the metaphysis and results in an elongation of the bony trabeculae. The mechanism that governs the highly coordinated sequence of events that underlies the growth of the long bones is complex; it is subject to influence by genetic, hormonal, nutritional, environmental, and pathological factors., (© 2018 Nestlé Nutrition Institute, Switzerland/S. Karger AG, Basel.)

Epiphyseal fusion in primates is a process that occurs in a regular sequence spanning a period of years and thus provides biological anthropologists with a useful marker of maturity that can be used to assess age and stage of development. Despite the many studies that have catalogued fusion timing and sequence pattern, comparatively little research has been devoted to understanding why these sequences exist in the first place. Answering this question is not necessarily intuitive; indeed, given that neither taxonomic affinities nor recent adaptations have been clearly defined, it is a challenge to explain this process in evolutionary terms. In all mammals, there is a tendency for the fusion of epiphyses at joints to occur close in sequence, and this has been proposed to relate to locomotor adaptations. Further consideration of the evidence suggests that linking locomotor behavior to sequence data alone is difficult to prove and may require a different type of evidence. Epiphyseal fusion should be considered in the context of other parameters that affect the developing skeleton, including how joint morphology relates to growth in length, as well as other possible morphological constraints. In recent years, developmental biology has been providing a better understanding of the molecular regulators of epiphyseal fusion. At some point in the near future, we may be able to link our understanding of the genetics of fusion timing to the possible selective mechanisms that are responsible for these sequences., (© 2017 Wiley Periodicals, Inc.)

Endochondral ossification in the diaphysis of long bones has been studied in-depth during fetal development but not postnatally in the epiphysis. Immunohistochemical studies revealed that Sox9 and Col2 expressing immature chondrocytes in the epiphysis transition into prehypertrophic and hypetrophic chondrocytes and finally into osteoblasts expressing Col1 and BSP during postnatal day 7-10, when serum levels of thyroid hormone (TH) rise. Lineage tracing using Rosa-td tomato Col2-Cre-ERT2 mice treated with tamoxifen indicated that the same Col2 expressing chondrocytes expressed prehypertrophic, hypertrophic, and subsequently bone formation markers in a sequential manner in euthyroid but not hypothyroid mice, thus providing evidence that chondrocyte to osteoblast transdifferentiation is TH-dependent. Vascular invasion was apparent at the time of bone formation but not earlier. In vitro studies revealed that TH acting via TRα1 promoted expression of SHH while TRβ1 activation increased IHH but inhibited SHH expression. SHH promoted expression of markers of immature chondrocytes but inhibited chondrocyte hypertrophy while IHH promoted chondrocyte hypertrophy. Based on our data, we propose a model in which TH acting through TRα1 and TRβ1, respectively, fine tune levels of SHH and IHH and, thereby control the transit of proliferating immature chondrocytes into mature hypertrophic chondrocytes to become osteoblasts at the epiphysis.

Injury to the anterior cruciate ligament (ACL) is becoming increasingly common in the skeletally immature population. Historically, there was a reluctance to operate on skeletally immature patients due to potential damage to the physis and subsequent growth disturbances; however, more recently, ACL reconstruction techniques specifically developed for this young population have shown good outcomes and low complication rates. In this article, we briefly discuss the modifiable and non-modifiable risk factors for ACL injury in children, options for conservative management for ACL rupture, and outcomes for delayed operative management. The main focus of the manuscript is to describe three operative technique options designed for ACL reconstruction in skeletally immature patients and to review the literature on outcomes and complications of these techniques. Two of these techniques, namely the Modified MacIntosh and the all-epiphyseal techniques, are often referred to as physeal-sparing, while the third, i.e. the transphyseal technique, is not. While different in approach and technique, these procedures have been shown to produce good outcomes and minimal complications in the skeletally immature population. Despite these positive reports, it is also essential to be aware of potential complications and the potential risk of recurrence.

Objective: The role of Snorc, a novel cartilage specific transmembrane proteoglycan, was studied during skeletal development using two Snorc knockout mouse models. Hypothesizing that Snorc, like the other transmembrane proteoglycans, may be a coreceptor, we also studied its interaction with growth factors., Methods: Skeletal development was studied in wild type (WT) and Snorc knockout mice during postnatal development by whole mount staining, X-ray imaging, histomorphometry, immunohistochemistry and qRT-PCR. Snorc promoter activity was studied by applying the LacZ reporter expressed by the targeting construct. Slot blot binding and cell proliferation assays were used to study the interaction of Snorc with several growth factors., Results: Snorc expression was localized in the knee epiphyses especially to the prehypertrophic chondrocytes delineating the cartilage canals and secondary ossification center (SOC). Snorc was demonstrated to have a glycosaminoglycan independent affinity to FGF2 and it inhibited FGF2 dependent cell growth of C3H101/2 cells. In Snorc deficient mice, SOCs in knee epiphyses were smaller, and growth plate (GP) maturation was disturbed, but total bone length was not affected. Central proliferative and hypertrophic zones were enlarged with higher extracellular matrix (ECM) volume and rounded chondrocyte morphology at postnatal days P10 and P22. Increased levels of Ihh and Col10a1, and reduced Mmp13 mRNA expression were observed at P10., Conclusions: These findings suggest a role of Snorc in regulation of chondrocyte maturation and postnatal endochondral ossification. The interaction identified between recombinant Snorc core protein and FGF2 suggest functions related to FGF signaling., (Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Background: Current concepts of linear growth include genetic, endocrine and nutritional factors. Limited and controversial results exist regarding the effect of physical activity (PA) on linear growth. In 2009, we showed that PA promotes foot length in hypoactive children with Prader-Willi-Syndrome. In the present study we tested the hypothesis that PA related epiphyseal loading has a positive modulating effect on linear growth in healthy school children., Methods: In 99 healthy schoolchildren, we measured height, foot length and PA by tri-axial accelerometry. PA related epiphyseal loading was expressed as the product between mass (body weight) and acceleration (vector magnitude). Correlation between height, foot length and PA were calculated taking into account co-variables age, sex, parental height, lean and fat mass measured by DEXA., Results: Height SDS (P<0.015, r=0.245) as well as foot length SDS (P<0.001, r=0.363) correlated with PA. Multiple linear regression models showed that muscle mass expressed by lean body mass has higher correlation with PA, height SDS and foot length SDS than fat mass., Conclusions: This study shows that physically less active children are shorter and have shorter feet. In analogy to the "muscle bone unit", we propose a "muscle epiphyseal unit" which regulates local bone growth as long as epiphyseal plates are still open.

Background: The relationship between the activity of the epiphysis and gonads in rats of different sex and age in different seasons of the year was determined by studying the levels of melatonin and testosterone in the blood plasma. Determination of the levels of melatonin and testosterone in the serum of rats was carried out by enzyme-linked immunosorbent assay. To assess the relationship between the levels of melatonin and testosterone the correlation coefficient was calculated. Based on the study of the levels of melatonin and testosterone in serum the circannual relationship between the activity of the pineal gland and gonads in males of reproductive age has been determined. In females, the relationship between the levels of melatonin and testosterone without the circannual dependence has been determined. The strongest correlation between melatonin and testosterone is present in males at the age of 9 months in autumn, and it corresponds to the human age of 29-30 years.

Proper functioning of the hand relies on its capacity to rotate and point the palm upward (i.e. supination) or downward (i.e. pronation) when standing up with the elbow in 90° flexion. Hand rotation is possible because of forearm rotation and also rotation of the whole upper limb at the shoulder. Two distinct mechanisms contribute to hand rotation: one in which the ulna is immobile and another in which the ulna is mobile. In this review, we first summarize how evolution of the human species has led to the progressive development of specific forearm anatomy that allows for pronation and supination. Then we analyze how the three joints of the forearm (i.e. proximal, middle and distal radioulnar joints), in association with the characteristic shape of both forearm bones, allow the forearm to rotate around a single axis. Lastly, we describe the neuromuscular anatomy that controls these complex rotational movements. The anatomical and biomechanical points developed in this paper are analyzed while considering clinical applications., (Copyright © 2016 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

People aged 18 years could be punished lightly or diminished criminal responsibility, even be spared the death sentence, which has important meaning in Chinese judicatory adjudication. The epiphysis of long bones from human limbs and the secondary sexual characteristics almost have developed completely before 18 years old. Clavicle epiphysis is one of the articular metaphysis which has a late epiphyseal closure. The recent studies in exploring the rule of clavicle epiphyseal by multi-imaging technology shows that the development of clavicle epiphysis has some value in age estimation of 18 years old. CT, especially thin-section CT, is widely used at present. However, thin-section CT scanning has great net radiation, which is not ethically acceptable if it is not for diagnosis and treatment. MRI is nonradioactive tomographic imaging and easy to evaluate, which is one of the future research directions in forensic age estimation using the medial clavicle. This paper summarizes the progress on the rule of clavicle epiphyseal closure, and analyzes and summarizes the feasibility of rule of clavicle epiphyseal closure applies on age estimation., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Background: Access to the medial half of the talus can be challenging even with an osteotomy. Although several techniques are presented in the literature, critical evaluation of fixation, union, and alignment is lacking. The chevron medial malleolar osteotomy provides advantages of perpendicular instrumentation access and wide exposure to the medial talus. Postoperative displacement resulting in malunion, and possibly provoking ankle osteoarthritis, is a known complication. The present study describes our experience with the osteotomy., Methods: A consecutive series cohort of 50 bi-plane chevron osteotomies performed from 2004 to 2013 were evaluated. Forty-six were secured using 2 lag screws, and 4 were secured using 2 lag screws and a medial buttress plate. Radiographic studies performed at 2, 6, and 12 weeks and at final follow-up were analyzed for postoperative displacement, malunion, non-union, and hardware-related complications., Results: At initial postoperative follow-up, 47 of 50 had adequate radiographs for review, and 18 of 47 (38.3%) showed some displacement when compared to the initial osteotomy fixation position. By final follow-up, 15 of 50 (30.0%) had measurable incongruence. Hardware removal was performed in 13 (26.0%) cases at an average of 2.4 years postoperation., Conclusion: Bi-plane medial malleolar chevron osteotomy fixed with 2 lag screws showed a 30.0% malunion rate with an average of 2 mm of incongruence on final follow-up radiographs, which is higher than what has been reported in the literature. In our practice, we now use a buttress plate and more recently have eliminated postoperative osteotomy displacement., Level of Evidence: Level IV, retrospective case series., (© The Author(s) 2016.)

Background: Recent evidence has suggested that cam morphology may be related to alterations in the capital femoral growth plate during adolescence. The purpose of this study was to evaluate the relationship between capital femoral growth plate extension and cam morphology in a longitudinal radiographic study., Methods: We used a historical, longitudinal radiographic collection to identify 96 healthy adolescents (54 boys and 42 girls) with at least 5 consecutive annual radiographs of the left hip including closure of the capital femoral physis. We reviewed 554 anteroposterior radiographs of the left hip to measure the anteroposterior modification of the alpha angle of Nötzli and of the superior epiphyseal extension ratio (EER), measured as the ratio of extension of the capital femoral epiphysis down the femoral neck relative to the diameter of the femoral head. Measurements were made at 3 points in femoral head maturation corresponding to the Oxford bone age (OBA) femoral head stages 5, 6, and 7/8., Results: There was a mean increase in the anteroposterior alpha angle (10.7° ± 14.0°) and EER (0.12 ± 0.08) between OBA stages 5 and 7/8, corresponding to maturation and closure of the capital femoral physis. There was a positive correlation between the final anteroposterior alpha angle and both the final EER (r = 0.60) and the change in the EER (r = 0.58). A receiver operating characteristic curve generated to predict an anteroposterior alpha angle of ≥78° through the EER demonstrated an area under the curve of 0.93, indicating that an increasing EER had excellent diagnostic accuracy for predicting concurrent cam morphology., Conclusions and Clinical Relevance: Superior epiphyseal extension was directly and temporally associated with an increase in anteroposterior alpha angle and more cam-like morphology. This alteration in the capital femoral epiphysis occurred immediately before physeal closure (OBA stage 7/8). Given the association of epiphyseal extension with activities that increase shear forces across the physis, we proposed that epiphyseal extension may be an adaptive mechanism to stabilize the physis and prevent slipped capital femoral epiphysis., (Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.)

Investigations of the bone system and body composition in Mars-500 test-subjects (prior to and on completion of the experiment) involved dual-energy X-ray absorptiometry (DXA) using the HOLOGIC Delphy densitometer and the protocol performed to examine cosmonauts. Bone density of lumber vertebrae and femoral proximal epiphysis, and body composition were measured. Reliable changes in vertebral density found in 3 test-subjects displayed different trends from +2.6 to -2.4%. At the same time, the experiment decreased significantly mineral density of the femoral proximal epiphysis, including the neck, in all test-subjects. Four test-subjects had cranial mineralization increased by 5-9%, same as in some cosmonauts after space flight. All tests-subjects incurred adipose loss from 2 to 7 kg; one test-subject lost 20 kg, i.e. his adipose mass became three times less. Changes in lean mass (1-3 kg) typically were negative; as for changes in lean mass of extremities, they could be linked with adherence to one or another type of physical activity. Therefore, extended exposure to confinement may affect mineralization of some parts of the skeleton. Unlike real space missions and long-term bedrest studies conducted at the Institute of Biomedical Problems in the past, Mars-500 did not cause clinically significant mineral losses (osteoporosis, osteopenia), probably because of the absence of effects of microgravity.

Objective: To compare regional proportions and spatial distributions of volumetric bone mineral density (BMDv) of the palmar aspect of the distal epiphysis of the third metacarpal bone (McIII) in limbs with or without a condylar fracture from Thoroughbred racehorses., Sample: McIIIs from cadavers of Thoroughbred racehorses with (n = 6 bones) and without (8) a condylar fracture., Procedures: BMDv and spatial distributions of BMDv in peripheral quantitative CT images of the distal epiphysis of McIIIs were quantitatively assessed with spatial analysis software. Relative proportions of voxels within 9 threshold categories of BMDv and spatial statistics for BMDv distribution were compared between fractured and nonfractured limbs., Results: No significant differences in BMDv characteristics were identified between fractured and nonfractured limbs, although fractured limbs had a lower proportion of voxels in the BMDv thresholds 700 to < 800 mg/cm(3) and 800 to < 900 mg/cm(3) but a higher proportion of voxels in the BMDv threshold 1,000 to < 1,100 mg/cm(3) for the central condylar region of the medial condyle. Results of spatial analysis reflected the response of bone to race training rather than differences between fractured and nonfractured limbs. In both limb groups, uniform clusters of low BMDv with areas of high BMDv were identified., Conclusions and Clinical Relevance: BMDv characteristics of the distal epiphysis of McIII reflected training load, and fracture characteristics were subtle. Serial imaging techniques in conjunction with detailed training data are required to elucidate the onset of the pathological response to load in horses.

Slipped capital femoral epiphysis (SCFE) is an orthopedic pathology in which damage of the growth plate leads to the anterosuperior displacement of the femoral body in respect to the femoral head. Despite being a widely studied disease, its etiology is still unknown. This study was carried out to determine the influence of the physeal-diaphysis angle, body mass, the presence of the perichondrial ring, the type of physical activity, and physeal thickness on SCFE. For this purpose, a finite element analysis of the hip joint and the femur-physis interface was carried out. With the computational model, the Von Mises stresses along the growth plate were calculated and subsequently analyzed statistically to find their correlation with the studied factors. It was found that body mass, the type of physical activity, and the presence of the perichondrial ring had more statistical relevance for the physeal stresses than the physeal-diaphysis angle and the physeal thickness. Thus, our work suggests that changes in growth plate inclination and thickness do not influence the etiology of SCFE.

Background: The effect of radial head implant length has been a subject of controversy, with the impact on clinical outcomes and forearm biomechanics being extensively studied. However, the impact of radial head diameter on forearm load transfer has not been examined. This study examined the influence of radial head implant diameter on forearm load transfer as measured by interosseous membrane tension and radiocapitellar joint contact characteristics., Methods: An upper extremity simulator was utilized to study five cadaveric specimens with three different radial head implant diameters (-2mm, anatomically sized, +2mm). A load sensing device was woven into the fibers of the central band of the interosseous membrane to quantify its tension. An inter-positional pressure measurement sensor was used to quantify radiocapitellar joint contact force and area. Axial loads of 160N were applied to the forearm during forearm rotation with the elbow at 90° of flexion., Findings: Changes to the radial head diameter did not change radiocapitellar contact force or area (P=0.4 and P=0.5 respectively). There was a linear relationship between radial head diameter and interosseous membrane tension; increasing radial head diameter increases the interosseous membrane tension (P=0.01)., Interpretation: Although radial head diameter was not found to alter radiocapitellar contact area or force, the interosseous membrane tension was impacted. After radial head arthroplasty, an increase in radial head implant diameter increases the interosseous membrane tension, with a potential for increased pain and stiffness. There is also a potential for increased proximal radioulnar joint contact pressures; resulting in stem loosening or radio-ulnar pain., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Rebound growth after hemiepiphysiodesis may be a normal event, but little is known about its causes, incidence or factors related to its intensity. The aim of this study was to evaluate rebound growth under controlled experimental conditions. A total of 22 six-week-old rabbits underwent a medial proximal tibial hemiepiphysiodesis using a two-hole plate and screws. Temporal growth plate arrest was maintained for three weeks, and animals were killed at intervals ranging between three days and three weeks after removal of the device. The radiological angulation of the proximal tibia was studied at weekly intervals during and after hemiepiphysiodesis. A histological study of the retrieved proximal physis of the tibia was performed. The mean angulation achieved at three weeks was 34.7° (standard deviation (sd) 3.4), and this remained unchanged for the study period of up to two weeks. By three weeks after removal of the implant the mean angulation had dropped to 28.2° (sd 1.8) (p < 0.001). Histologically, widening of the medial side was noted during the first two weeks. By three weeks this widening had substantially disappeared and the normal columnar structure was virtually re-established. In our rabbit model, rebound was an event of variable incidence and intensity and, when present, did not appear immediately after restoration of growth, but took some time to appear., (©2015 The British Editorial Society of Bone & Joint Surgery.)

The clavicle is the first bone to ossify in the developing embryo and the last to complete epiphyseal union. It is the latter sustained period of growth that has attracted the interest of skeletal biologists and forensic practitioners alike, who collectively recognize the important opportunity this bone affords to estimate skeletal age across the prenatal to early adult lifespan. Current research is largely directed towards evaluating the applicability of assessing fusion in the medial epiphysis, specifically for determining age of majority in the living. This study aims to contribute further insights, and inform medicolegal practice, by evaluating the Schmeling five-stage system for the assessment of clavicular development in a Western Australian population. We retrospectively evaluated high-resolution multiple detector computed tomography (MDCT) scans of 388 individuals (210 male; 178 female) between 10 and 35 years of age. Scans are viewed in axial and multiplanar reconstructed (MPR) images using OsiriX®. Fusion status is scored according to a five-stage system. Transition analysis is used to calculate age ranges and determine the mean age for transition between an unfused, fusing and fused status. The maximum likelihood estimates (in years) for transition from unfused to fusing is 20.60 (male) and 19.19 (female); transition from fusing to complete fusion is 21.92 (male) and 21.47 (female). Results of the present study confirm the reliability of the assessed method and demonstrate remarkable consistency to data reported for other global populations.

Previous studies on different aspects of chimpanzee growth and development have documented dental eruption and development, long bone and somatic growth, and to a lesser extent, skeletal fusion. Such data are useful in comparative and evolutionary studies of growth and some aspects of life history evolution in apes and early hominids. However, few studies have integrated dental development and other aspects of skeletal development, and none of these have been able to incorporate a large study sample. This study documents dental mineralization and skeletal epiphyseal fusion in a mixed-sex sample of 155 Pan troglodytes skeletons, and aims to: a) document the pattern of dental and skeletal developmental in chimpanzees; b) compare male and female developmental patterns in chimpanzees; and c) compare these chimpanzee developmental patterns to general patterns of dental and skeletal development in published human studies. The analysis of both dental and skeletal development in this sample demonstrates clearly that dental development is complete before the fusion of the many skeletal epiphyses, in contrast to the pattern observed in humans. Age estimates for individuals were calculated using previously published regression equations for dental development and used to estimate fusion ages. These appear to be accurate in that our estimates are similar to published ranges. These data improve our understanding about chimpanzee dental and skeletal development and provide a basis for further comparison between extant apes and humans, as well as those extinct species represented by fossil partial skeletons., (© 2014 Wiley Periodicals, Inc.)

Only two distal epiphyses of a radius and ulna are consensually attributed to the holotype skeleton of Proconsul heseloni, KNM-RU 2036. Here, we describe seven adult and immature distal antebrachial (radial and ulnar) epiphyses from two other individuals of P. heseloni from the Lower Miocene deposits of the Kaswanga Primate Site (KPS), Rusinga Island, Kenya. Because KNM-RU 2036 and KNM-KPS individuals III and VIII are conspecific and penecontemporaneous, their comparison provides the opportunity i) to characterize, for the first time, the morphological variation of the distal radioulnar joint in a Miocene ape, P. heseloni, and ii) to investigate the functional and evolutionary implications. Our results show that the distal antebrachial epiphyses of KNM-KPS III and VIII correspond to stages of bone maturation that are more advanced than those of KNM-RU 2036 (larger articulations and sharper articular borders and ligament attachments that are more developed). Accordingly, functional interpretations based solely on the skeleton of KNM-RU 2036 have involved an underestimation of the forearm rotation abilities of P. heseloni. In particular, the KPS fossils do not exhibit the primitive morphology of distal radioulnar syndesmosis, as those of KNM-RU 2036 and most nonhominoid primates, but rather the morphology of an incipient diarthrosis (as in extant lorisines and hominoids). The distal radioulnar diarthrosis permits more mobility and maintenance of the wrist during repeated and slow rotation of the forearms, which facilitates any form of quadrupedal locomotion on discontinuous and variably oriented supports. By providing the oldest evidence of a distal radioulnar joint in an early Miocene hominoid, the main conclusions of this study are consistent with the role of cautious climbing as a prerequisite step for the emergence of positional adaptations in apes., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Mechanical stimuli play a significant role in the process of long bone development as evidenced by clinical observations and in vivo studies. Up to now approaches to understand stimuli characteristics have been limited to the first stages of epiphyseal development. Furthermore, growth plate mechanical behavior has not been widely studied. In order to better understand mechanical influences on bone growth, we used Carter and Wong biomechanical approximation to analyze growth plate mechanical behavior, and explore stress patterns for different morphological stages of the growth plate. To the best of our knowledge this work is the first attempt to study stress distribution on growth plate during different possible stages of bone development, from gestation to adolescence. Stress distribution analysis on the epiphysis and growth plate was performed using axisymmetric (3D) finite element analysis in a simplified generic epiphyseal geometry using a linear elastic model as the first approximation. We took into account different growth plate locations, morphologies and widths, as well as different epiphyseal developmental stages. We found stress distribution during bone development established osteogenic index patterns that seem to influence locally epiphyseal structures growth and coincide with growth plate histological arrangement., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Background: Subchondral drilling is an established marrow stimulation technique., Hypothesis: Osteochondral repair is improved when the subchondral bone is perforated with small drill holes, reflecting the physiological subchondral trabecular distance., Study Design: Controlled laboratory study., Methods: A rectangular full-thickness chondral defect was created in the trochlea of adult sheep (n = 13) and treated with 6 subchondral drillings of either 1.0 mm (reflective of the trabecular distance) or 1.8 mm in diameter. Osteochondral repair was assessed after 6 months in vivo by macroscopic, histological, and immunohistochemical analyses and by micro-computed tomography., Results: The application of 1.0-mm subchondral drill holes led to significantly improved histological matrix staining, cellular morphological characteristics, subchondral bone reconstitution, and average total histological score as well as significantly higher immunoreactivity to type II collagen and reduced immunoreactivity to type I collagen in the repair tissue compared with 1.8-mm drill holes. Analysis of osteoarthritic changes in the cartilage adjacent to the defects revealed no significant differences between treatment groups. Restoration of the microstructure of the subchondral bone plate below the chondral defects was significantly improved after 1.0-mm compared to 1.8-mm drilling, as shown by higher bone volume and reduced thickening of the subchondral bone plate. Likewise, the microarchitecture of the drilled subarticular spongiosa was better restored after 1.0-mm drilling, indicated by significantly higher bone volume and more and thinner trabeculae. Moreover, the bone mineral density of the subchondral bone in 1.0-mm drill holes was similar to the adjacent subchondral bone, whereas it was significantly reduced in 1.8-mm drill holes. No significant correlations existed between cartilage and subchondral bone repair., Conclusion: Small subchondral drill holes that reflect the physiological trabecular distance improve osteochondral repair in a translational model more effectively than larger drill holes., Clinical Relevance: These results have important implications for the use of subchondral drilling for marrow stimulation, as they support the use of small-diameter bone-cutting devices., (© 2014 The Author(s).)

The aim of the study was to use spatial and multiple correspondence analysis (MCA) to describe and compare the regional proportion and spatial pattern of volumetric bone mineral density (BMDv) values within loaded regions of the plantar metatarsal epiphysis of young horses in race training. A single 2 mm transverse peripheral quantitative computed tomography 'slice', 10 mm proximal from the distal limit of the sagittal ridge of the distal metatarsal epiphysis was obtained from 14 2-year-old Thoroughbred fillies (7 exercised and 7 controls). Six regions of interest were generated and examined for relative BMDv using MCA. The spatial distribution of BMDv was statistically examined at two sites loaded by the proximal sesamoid bones using geographical information software. The BMDv response was focal with distinct regional differences in relation to load. Deposition of new bone within existing high density bone contributed to a greater bone fraction and the distinct profile of clusters of uniformly distributed high density bone as well as a lower proportion of lower density bone in exercised horses. The MCA and spatial analysis provided statistical techniques to quantify and describe non-invasively the exercise induced changes in bone that had previously been described using microradiography of thin slices and by block-face imaging. These statistical techniques may prove useful in quantifying spatial patterns of response to load., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The establishment of radiation-free examination procedures in the field of forensic age diagnostics in living persons is to be considered of special scientific interest so as to minimize necessary exposure to X-rays while facilitating additional assessment of skeletal development in all cases. To this end, the advantages offered by magnetic resonance imaging in securing a practical application which is as unrestricted and complication-free as possible should be among the methods exploited in investigating such indicators of skeletal maturity. Within the framework of a retrospective study, we investigated the ossification status of the proximal tibial epiphysis on the MRI scans of 124 females and 166 males aged between 10 and 30 years. All the images had been generated on a 3.0 T scanner using a T1-weighted turbo spin-echo sequence. When evaluating the ossification stage, a combination of modified classifications proposed by Schmeling et al. and by Kellinghaus et al. was used. The statistical evaluation included calculation of a variety of measures to describe specific ossification stages as well as kappa coefficients to assess intra- and inter-observer agreement on diagnoses of individual stages. In forensic contexts, completion of the 14th year of life can be adequately evidenced in females with an ossification stage IV according to Schmeling et al. and in males with an ossification stage III c according to Kellinghaus et al. or an ossification stage IV according to Schmeling et al. In forensic contexts, the presence of an ossification stage IV according to Schmeling et al. can prove that the age of 16 years has been exceeded only in the male sex, whereby for age estimation purposes the diagnosis should be in line with other skeletal maturity indicators. The results available displayed a high degree of intra- and inter-observer agreement. Examination of the ossification status of the proximal tibial epiphysis using magnetic resonance imaging represents an effective additional tool for use in radiation-free forensic age diagnostics in living persons.

Mammalian skeletons are formed through two distinct processes, intramembranous ossification and endochondral ossification. During the endochondral ossification, indian hedgehog (Ihh) /parathyroid hormone-related protein (PTHrP) negative-feedback loop regulates the distance between epiphysis and the layer of hypertrophic chondrocytes. Ihh also stimulates bone formation. Based on such knowledge, bioactive molecule-loaded artificial bones are expected to achieve efficient bone regeneration without cell transplantation.

Objectives: Preterm infants are born with low bone mineral. Neonatal stress further impedes bone mineralization. Clinical evidence suggests that tactile and kinesthetic stimulation (TKS) improves bone phenotype and decreases stress response. Clinical and translational studies indicate the IGF-1 axis, responsible for postnatal growth and bone mineralization, is a key player. We hypothesized that TKS would attenuate the negative impact of neonatal stress on bone phenotype and the IGF-1 axis in weanling rats., Methods: Neonatal stress (STRESS) or TKS (STRESS + 10min TKS) was administered from D6 to D10. Control animals received standard care. Tissue was harvested on D21. Dual energy x-ray absorptiometry (DXA) and bone morphometry were performed and serum osteocalcin, type I procollagen N-terminal propeptide (PINP), tartrate-resistant acid phosphatase (TRAP), and bone and liver mRNA levels of IGF-1, IGF-1 receptor (IGF-1R), and growth hormone receptor (GHR) were measured., Results: Neonatal stress increased bone mineral content (BMC), area (BA), growth plate width, liver IGF-1 mRNA, and serum IGF-1. TKS maintained areal bone mineral density (aBMD) and bone specific IGF-1 and IGF-1R mRNA while STRESS decreased compared to controls., Conclusions: Neonatal stress results in apparent accelerated growth response. TKS differed from STRESS with improved tibia aBMD and increased bone specific IGF-1 mRNA.

In order to increase the reliability of forensic age estimations in living adolescents and young adults without justification for X-ray examinations, the establishment of radiation-free imaging procedures is desirable. In this study, the ossification stage of the right-hand distal fibula epiphysis was sonographically determined prospectively in 309 male and 307 female healthy volunteers. For this purpose a four-stage classification system was used. A sonographically determined ossification stage 3 permits the proof of completion of age 13 in boys and the proof of completion of age 12 in girls. In case of an ossification stage 4 the completion of age 14 in boys and the completion of age 13 in girls can be certified. In order to increase the level of reliability of age estimates, findings should be collected by at least two independent examiners who are experienced in the sonography of skeletons, followed by consensus-building.

Unlabelled: Micro-finite element analysis applied to high-resolution (0.234-mm length scale) MRI reveals greater whole and cancellous bone stiffness, but not greater cortical bone stiffness, in the distal femur of female dancers compared to controls. Greater whole bone stiffness appears to be mediated by cancellous, rather than cortical bone adaptation., Introduction: The purpose of this study was to compare bone mechanical competence (stiffness) in the distal femur of female dancers compared to healthy, relatively inactive female controls., Methods: This study had institutional review board approval. We recruited nine female modern dancers (25.7±5.8 years, 1.63±0.06 m, 57.1±4.6 kg) and ten relatively inactive, healthy female controls matched for age, height, and weight (32.1±4.8 years, 1.6±0.04 m, 55.8±5.9 kg). We scanned the distal femur using a 7-T MRI scanner and a three-dimensional fast low-angle shot sequence (TR/TE=31 ms/5.1 ms, 0.234 mm×0.234 mm×1 mm, 80 slices). We applied micro-finite element analysis to 10-mm-thick volumes of interest at the distal femoral diaphysis, metaphysis, and epiphysis to compute stiffness and cross-sectional area of whole, cortical, and cancellous bone, as well as cortical thickness. We applied two-tailed t-tests and ANCOVA to compare groups., Results: Dancers demonstrated greater whole and cancellous bone stiffness and cross-sectional area at all locations (p<0.05). Cortical bone stiffness, cross-sectional area, and thickness did not differ between groups (>0.08). At all locations, the percent of intact whole bone stiffness for cortical bone alone was lower in dancers (p<0.05). Adjustment for cancellous bone cross-sectional area eliminated significant differences in whole bone stiffness between groups (p>0.07), but adjustment for cortical bone cross-sectional area did not (p<0.03)., Conclusions: Modern dancers have greater whole and cancellous bone stiffness in the distal femur compared to controls. Elevated whole bone stiffness in dancers may be mediated via cancellous, rather than cortical bone adaptation.

The talus is used in many kinds of studies on primates including fossil species, and most of the individuals studied are adults. One of the most important indicators of adult individuals is epiphyseal closure; however, because the talus has no epiphysis, it is difficult to determine the maturity of the talus. The calcaneus has one epiphysis, and it has been used along with the talus in some analyses. The objective of this study was to quantify the maturation trajectory of the talus using epiphyseal closure of the calcaneus as a benchmark. We used 71 skeletons of free-ranging Macaca fuscata fuscata males of known day-age. We did not identify any size increase with age in talar dimensions among specimens with complete calcaneal epiphyseal closure. Thus, in male M. fuscatafuscata, the maturation trajectory of the talus can be quantified using epiphyseal closure of the calcaneus as a benchmark., (Copyright © 2012 S. Karger AG, Basel.)

Bone age (BA) indicates more clearly than chronologic age how far an individual has progressed toward full maturity, and predicts the potential for further growth. Single or serial skeletal age estimations help to confirm the diagnosis of normal puberty and normal pubertal variants such as constitutional delay of growth and puberty, premature therlache, and precocious adrenarche. BA can aid in the clinical workup of children whose sexual maturation is early or delayed. Although BA is considered a qualitative rather than quantitative measure, it serves to round out the clinical picture, providing information without which diagnosis could not be achieved., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Nowadays, due to the global increase in migration movements, forensic age estimation of living young adults has become an important focus of interest. Minors often have no identification documents providing their correct birth dates. Establishing the age of majority is therefore fundamental in order to determine whether juvenile penal systems or penal systems in force for adults are to be applied. Radiological examination of the clavicles is one of the methods recommended by the Study Group on Forensic Age Diagnostics. In this retrospective study, a sample of chest radiographs of 274 subjects, aged between 12 and 25 years, was studied according to Schmeling's method in order to examine the ossification of both medial clavicular epiphyses. All stage classifications were evaluated by five examiners. Intra- and inter-examiner reliability was analysed by Cohen's K statistic. Intra-examiner agreement was insufficient for two of the experts. Inter-examiner agreement, among the other three operators, was moderate (K = 0.509). Study of reliability highlighted difficulties in interpretation, the need to select qualified personnel and choice of the best radiographic image in order to reduce any anatomic overlaps. Although ossification of the medial clavicular epiphyses is recommended to assess whether an individual has already reached the age of majority or not, these results suggested that it is very difficult to clearly identify the five stages of ossification by using conventional chest radiography.

Unlabelled: The objective of this study was to examine the associations of neuromuscular and cardiovascular impairments with the bone strength index of the hemiparetic distal radius epiphysis in chronic stroke survivors. The results showed that grip strength is the most predominant predictor of the bone strength index., Introduction: The purpose of the study was to examine the associations of neuromuscular and cardiovascular impairments with the bone strength index of the hemiparetic distal radius epiphysis in chronic stroke survivors., Methods: Sixty-five chronic stroke survivors and 34 healthy control subjects underwent scanning of the distal radius epiphyseal site on both sides using peripheral quantitative computed tomography to measure trabecular volumetric bone mineral density (vBMD) (mg/cm(3)), total vBMD (mg/cm(3)), total area (mm(2)), and compressive bone strength index (cBSI) (g(2)/cm(4)). Various indicators of neuromuscular (grip strength, spasticity) and cardiovascular function (vascular elasticity, oxygen consumption during 6-min walk test) were evaluated., Results: Analysis of variance revealed a significant main effect of side (p < 0.001) and group × side interaction (p < 0.05) for total BMC, total vBMD, trabecular vBMD, and cBSI (p < 0.05), with the stroke group showing greater side-to-side difference in these variables. However, no significant side-to-side difference in total area was detected in either group (p > 0.05). Sex-specific analysis yielded similar results. Multiple regression analyses revealed that the cBSI of the hemiparetic distal radius epiphysis had a stronger association with neuromuscular factors than cardiovascular factors. Overall, grip strength was the strongest determinant of the cBSI of the hemiparetic distal radius epiphysis (p < 0.01)., Conclusions: Muscle weakness is the most predominant determinant of cBSI in the hemiparetic distal radius epiphysis among chronic stroke patients. Future studies should investigate the efficacy of different muscle-strengthening strategies in enhancing bone strength of this skeletal site in the chronic stroke population.

The use of magnetism in tissue engineering is a very promising approach, in fact magnetic scaffolds are able not only to support tissue regeneration, but they can be activated and work like a magnet attracting functionalized magnetic nanoparticles (MNPs) injected close to the scaffold enhancing tissue regeneration. This study aimed to assess the in vivo biocompatibility and osteointegrative properties of novel magnetic scaffolds. Two hydroxyapatite/collagen (70/30 wt %) magnetic scaffolds were magnetized with two different techniques: direct nucleation of biomimetic phase and superparamagnetic nanoparticles (MNPs) on self-assembling collagen fibers (MAG-A) and scaffold impregnation in ferro-fluid solution (MAG-B). Magnetic scaffolds were implanted in rabbit distal femoral epiphysis and tibial mid-diaphysis. Histopathological screening showed no inflammatory reaction due to MNPs. Significantly higher bone healing rate (ΔBHR) results were observed in MAG-A in comparison to MAG-B. Significant differences were also found between experimental times with an increase in ΔBHR from 2 to 4 weeks for both scaffolds in trabecular bone, while only for MAG-B (23%, p < 0.05) in cortical bone. The proposed magnetic scaffolds seem to be promising for magnetic guiding in orthopedic tissue engineering applications and they will be suitable to treat also several pathologies in regenerative medicine area., (Copyright © 2012 Wiley Periodicals, Inc.)

We model trabecular bone as a nanocomposite material with hierarchical structure and predict its elastic properties at different structural scales. The analysis involves a bottom-up multi-scale approach, starting with nanoscale (mineralized collagen fibril) and moving up the scales to sub-microscale (single lamella), microscale (single trabecula) and mesoscale (trabecular bone) levels. Continuum micromechanics methods, composite materials laminate theory and finite-element methods are used in the analysis. Good agreement is found between theoretical and experimental results.

Fusion of skeletal elements provides markers for timing of growth and is one component of a chimpanzee's physical development. Epiphyseal closure defines bone growth and signals a mature skeleton. Most of what we know about timing of development in chimpanzees derives from dental studies on Pan troglodytes. Much less is known about the sister species, Pan paniscus, with few in captivity and a wild range restricted to central Africa. Here, we report on the timing of skeletal fusion for female captive P. paniscus (n = 5) whose known ages range from 0.83 to age 11.68 years. Observations on the skeletons were made after the individuals were dissected and bones cleaned. Comparisons with 10 female captive P. troglodytes confirm a generally uniform pattern in the sequence of skeletal fusion in the two captive species. We also compared the P. paniscus to a sample of three unknown-aged female wild P. paniscus, and 10 female wild P. troglodytes of known age from the Taï National Park, Côte d'Ivoire. The sequence of teeth emergence to bone fusion is generally consistent between the two species, with slight variations in late juvenile and subadult stages. The direct-age comparisons show that skeletal growth in captive P. paniscus is accelerated compared with both captive and wild P. troglodytes populations. The skeletal data combined with dental stages have implications for estimating the life stage of immature skeletal materials of wild P. paniscus and for more broadly comparing the skeletal growth rates among captive and wild chimpanzees (Pan), Homo sapiens, and fossil hominins., (Copyright © 2012 Wiley Periodicals, Inc.)

Despite clinical efforts to treat growth disturbances only little is known about the growth potential of the different zones of the growth plate. The aim of this study was to investigate the growth potential of different zones of the growth plate. A total of 20 New Zealand White rabbits were used for this experiment. The right and left ulna of each animal were used resulting in a total of 40 ulnae. Animals were assigned into five groups. In groups I and II resection of the metaphyseal (n = 12) or the epiphyseal (n = 6) segment of the growth plate was performed. In group III resection of the growth plate and re-implantation was performed (n = 6). In group IV the growth plate was resected and re-implanted after a 180° rotation (n = 6). Animals in group V served as controls. Histologic and radiologic examinations were performed to evaluate the growth process at 1, 2, 4, and 12 weeks following surgery. In group I, III, and IV temporary growth disturbance which was compensated within a short time was observed. Resection of the epiphyseal part resulted in growth arrest of the distal ulna in combination with normal growth of the radius which led to and valgus deformity of the limb. The results of this study indicate the importance of the reserve zone for the functioning of the growth plate., (Copyright © 2011 Orthopaedic Research Society.)

Purpose: Fusionless growth modulation is an attractive alternative to conventional treatments of idiopathic scoliosis. To date, fusionless devices achieve unilateral growth modulation by compressing the intervertebral disc. This study explores a device to control spinal alignment and vertebral morphology via growth modulation while excluding the disc in a porcine model., Methods: A device that locally encloses the vertebral growth plate exclusive of the disc was introduced anteriorly over T5-T8 in four immature pigs (experimental) while three underwent surgery without instrumentation (sham) and two were selected as controls. Bi-weekly coronal and lateral radiographs were taken over the 12-week follow-up to document vertebral morphology and spinal alignment modifications via an inverse approach (creation of deformity)., Results: All animals completed the experiment with no postoperative complications. Control and sham groups showed no significant changes in spinal alignment. Experimental group achieved a final coronal Cobb angle of 6.5° ± 3.5° (constrained to the four instrumented levels) and no alteration to the sagittal profile was observed. Solely the experimental group ended with consistent vertebral wedging of 4.1° ± 3.6° amounting to a cumulative wedging of up to 25° and a concurring difference in left/right vertebral height of 1.24 ± 1.86 mm in the coronal plane., Conclusions: The proposed intravertebral epiphyseal device, for the early treatment of progressive idiopathic scoliosis, demonstrated its feasibility by manipulating spinal alignment through the realization of local growth modulation exclusive of the intervertebral disc.

Developing bone consists of epiphysis, metaphysis and diaphysis. The secondary ossification centre (SOC) appears and grows within the epiphysis, involving two histological stages. Firstly, cartilage canals appear; they carry hypertrophy factors towards the central area of the epiphysis. Canal growth and expansion is modulated by stress on the epiphysis. Secondly, the diffusion of hypertrophy factors causes SOC growth. Hypertrophy is regulated by biological and mechanical factors present within the epiphysis. The finite element method has been used for solving a coupled system of differential equations for modelling these histological stages of epiphyseal development. Cartilage canal spatial-temporal growth patterns were obtained as well as the SOC formation pattern. This model qualitatively agreed with experimental results reported by other authors., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Study Design: A descriptive study of the epiphyseal ring's structural design along the thoracolumbar spine., Objective: To characterize and analyze the shape and size of the epiphyseal ring, to better understand its function., Summary of Background Data: The literature is lacking in metrical data pertaining to the epiphyseal ring that is usually described as a narrow bony labrum on which the external fibers of the anulus fibrosus are anchored. Most researchers express doubts as to whether the term epiphysis is justified in this case., Methods: The sample studied included 240 human skeletons (vertebrae T4-L5) from a normal adult population (divided by sex, ethnicity, and age). Measurements of the vertebral body and epiphyseal ring were taken using a digital caliper at four different locations: anterior, posterior, right, left. In addition, each vertebral surface was photographed and the epiphyseal ring area measured (using image analyzer software Image J)., Results: We found that relative to vertebral body size throughout the thoracolumbar spine, the anterior section of the ring was the widest and the posterior section the narrowest. The lateral parts presented intermediate values. Relative to the discal area, the epiphyseal ring area gradually decreased from T7 to T12 and increased from T12 to L4. The area of the inferior ring was always larger than the superior ring (significant only for lumbar vertebrae), regardless of sex, ethnicity, and age., Conclusion: The epiphyseal ring varies largely in size and shape along the thoracolumbar spine. Much of its metrical properties are dictated by the applied mechanical stress regime during various movements, and/or the general anatomic structure of the spine.