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Concept: Femur

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We describe adaptations for a semiaquatic lifestyle in the dinosaur Spinosaurus aegyptiacus. These adaptations include retraction of the fleshy nostrils to a position near the mid-region of the skull and an elongate neck and trunk that shift the center of body mass anterior to the knee joint. Unlike terrestrial theropods, the pelvic girdle is downsized, the hind limbs are short, and all of the limb bones are solid without an open medullary cavity, for buoyancy control in water. The short, robust femur with hypertrophied flexor attachment and the low, flat-bottomed pedal claws are consistent with aquatic foot-propelled locomotion. Surface striations and bone microstructure suggest that the dorsal “sail” may have been enveloped in skin that functioned primarily for display on land and in water.

Concepts: Skull, Patella, Theropoda, Femur, Spinosaurus, Joint, Knee, Bone

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Synopsis The hallmark features of patellar tendinopathy are (1) pain localized to the inferior pole of the patella and (2) load related pain that increases with the demand on the knee extensors, notably in activities that store and release energy in the patellar tendon. While imaging may assist in differential diagnosis, the diagnosis of patellar tendinopathy remains clinical, as asymptomatic tendon pathology may exist in people who have pain from other anterior knee sources. A thorough examination is required to diagnose patellar tendinopathy and contributing factors. Management of patellar tendinopathy should focus on progressively developing load tolerance of the tendon, the musculoskeletal unit, and the kinetic chain as well as addressing key biomechanical and other risk factors. Rehabilitation can be slow and sometimes frustrating. This review aims to assist clinicians with key concepts related to examination, diagnosis, and management of patellar tendinopathy. Difficult clinical presentations (eg, highly irritable tendon, systemic comorbidities) as well as common pitfalls such as unrealistic rehabilitation timeframes and over-reliance on passive treatments are also discussed. J Orthop Sports Phys Ther, Epub 21 Sep 2015. doi:10.2519/jospt.2015.5987.

Concepts: Medical diagnosis, Femur, Medical terms, Patellar ligament, Differential diagnosis, Patella, Knee, Tibia

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Ouranosaurus nigeriensis is an iconic African dinosaur taxon that has been described on the basis of two nearly complete skeletons from the Lower Cretaceous Gadoufaoua locality of the Ténéré desert in Niger. The entire holotype and a few bones attributed to the paratype formed the basis of the original description by Taquet (1976). A mounted skeleton that appears to correspond to O. nigeriensis has been on public display since 1975, exhibited at the Natural History Museum of Venice. It was never explicitly reported whether the Venice specimen represents a paratype and therefore, the second nearly complete skeleton reported in literature or a third unreported skeleton. The purpose of this paper is to disentangle the complex history of the various skeletal remains that have been attributed to Ouranosaurus nigeriensis (aided by an unpublished field map of the paratype) and to describe in detail the osteology of the Venice skeleton. The latter includes the paratype material (found in 1970 and collected in 1972), with the exception of the left femur, the right coracoid and one manus ungual phalanx I, which were replaced with plaster copies, and (possibly) other manus phalanges. Some other elements (e.g., the first two chevrons, the right femur, the right tibia, two dorsal vertebrae and some pelvic bones) were likely added from other individual/s. The vertebral column of the paratype was articulated and provides a better reference for the vertebral count of this taxon than the holotype. Several anatomical differences are observed between the holotype and the Venice specimen. Most of them can be ascribed to intraspecific variability (individual or ontogenetic), but some are probably caused by mistakes in the preparation or assemblage of the skeletal elements in both specimens. The body length of the Venice skeleton is about 90% the linear size of the holotype. Osteohistological analysis (the first for this taxon) of some long bones, a rib and a dorsal neural spine reveals that the Venice specimen is a sub-adult; this conclusion is supported by somatic evidence of immaturity. The dorsal ‘sail’ formed by the elongated neural spines of the dorsal, sacral and proximal caudal vertebrae characterizes this taxon among ornithopods; a display role is considered to be the most probable function for this bizarre structure. Compared to the mid-1970s, new information from the Venice specimen and many iguanodontian taxa known today allowed for an improved diagnosis of O. nigeriensis.

Concepts: Spinous process, Femur, Skeletal system, Animal anatomy, Skeleton, Bone, Vertebra, Vertebral column

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Idiopathic avascular necrosis (AVN) of bone causes significant morbidity in adults although the pathophysiology is unknown. The present treatment options include systemic biphosphonate therapy and local bone drilling decompression, ameliorating the healing process and their by render the weight bearing femur head less vulnerable to collapse. In the present study we demonstrate the involvement of heparanase in AVN and in the acceptable treatments.

Concepts: Healing, Present, Heart, 2006 albums, Inflammation, Femur, Femur head, Avascular necrosis

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To the authors' knowledge, few reports have been published in the English literature of using total knee arthroplasty and total hip arthroplasty for the treatment of hereditary multiple exostoses. This article describes 2 patients with hereditary multiple exostoses, 1 treated with total hip arthroplasty and 1 treated with total knee arthroplasty. Bony deformities make arthroplasty uniquely challenging in patients undergoing total hip or knee arthroplasty. An expanded metaphysis of the proximal femur, coxa valga deformity, and the presence of hardware from previous reconstructive surgeries can make total hip arthroplasty technically difficult. Substantial bony deformity of the distal femur, valgus deformity of the knee, and sizing issues that necessitate custom implants can make total knee arthroplasty difficult. The most common bony deformities in hereditary multiple exostoses are short stature, limb-length discrepancy, valgus deformity at the knee and ankle, and asymmetry of the pectoral and pelvic girdles. Most reported surgical treatments for patients with hereditary multiple exostoses focus on the pediatric population or the management of malignant transformation of exostoses. Studies that specifically address the conditions associated with knee deformities focus on extra-articular deformity correction rather than arthroplasty.When arthroplasty is necessary in this patient population, an understanding of the commonly occurring deformities can help with preoperative planning and surgical management. All painful lesions must be evaluated for malignant transformation. Bone scans can be useful during workup. All specimens should be sent for pathologic evaluation. Such patients are challenging because of the distorted hip anatomy and valgus knee deformity. The current 2 cases illustrate specific challenges that can be anticipated and underscore key principles for arthroplasty in the management of hereditary multiple exostoses.

Concepts: Valgus deformity, Implants, Skeletal disorders, Hip replacement, Hip, Pelvis, Varus deformity, Femur

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PURPOSE: There is a lot of inter-individual variation in the rotational anatomy of the distal femur. This study was set up to define the rotational anatomy of the distal femur in the osteo-arthritic knee and to investigate its relationship with the overall coronal alignment and gender. METHODS: CT-scans of 231 patients with end-stage knee osteo-arthritis prior to TKA surgery were obtained. This represents the biggest series published on rational geometry of the distal femur in literature so far. RESULTS: The posterior condylar line (PCL) was on average 1.6° (SD 1.9) internally rotated relative to the surgical transepicondylar axis (sTEA). The perpendicular to trochlear anteroposterior axis (⊥TRAx) was on average 4.8° (SD 3.3°) externally rotated relative to the sTEA. The relationship between the PCL and the sTEA was statistically different in the different coronal alignment groups (p < 0.001): 1.0° (SD 1.8°) in varus knees, 2.1° (SD 1.8°) in neutral knees and 2.6° (SD 1.8°) in valgus knees. The same was true for the ⊥TRAx in these 3 groups (p < 0.02).There was a clear linear relationship between the overall coronal alignment and the rotational geometry of the distal femur. For every 1° in coronal alignment increment from varus to valgus, there is a 0.1° increment in posterior condylar angle (PCL vs sTEA). CONCLUSION: The PCL was on average 1.6° internally rotated relative to the sTEA in the osteo-arthritic knee. The relationship between the PCL and the sTEA was statistically different in the different coronal alignment groups. LEVEL OF EVIDENCE: III.

Concepts: Valgus deformity, Rotation, Mathematics, Euclidean geometry, Patella, Tibia, Knee, Femur

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To describe the incidence, 12-month prevalence, and course of lower extremity injuries that occurred during and after the Amgen Singelloop Breda in 2009. The design was based on a prospective cohort study with a population-based setting. In total, 3605 registered runners received a web-based baseline questionnaire of which 713 participants completed and returned it. Information about previous injuries, training programs, and demographic data were gathered at baseline. Site and intensity of running injuries and occurrence of new injuries were obtained from five post-race questionnaires. The main outcome measurement was lower extremity injury. The incidence of running injuries during the Amgen Singelloop Breda itself was 7.8%; most of these injuries occurred in the calf muscle, thigh, and knee joint. Three-month incidence of injuries during follow-up varied between 13.5% and 16.3%. During the 12-month follow-up period, 277 new running injuries were reported. Runners who ran more than 10 km are more susceptible to injury in comparison with runners who ran short distances (10 km or less). In total, 69.1% of running injuries resolves within 10 days. Running injuries are very common among recreational runners. Injuries mostly occur in the knee, thigh, and calf muscle.

Concepts: Cohort study, Demography, Iliotibial band syndrome, Knee, Epidemiology, Femur, Extension, Joint

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Abstract 1. The objective of this study was to evaluate the effects of dietary supplementation with phytase transgenic corn (maize) (PTC) which has a phytase activity of 21 000 units (U) phytase per kg of maize on productive performance, egg quality, tibia bone quality and phosphorus (P) excretion in laying hens. 2. In the experiment, 1800 44-week-old Hy-line brown laying hens were divided into 5 groups with 6 replicates per group and 60 hens per replicate. The experiment lasted for 12 weeks. The layers in the control group (control) were given a basal diet with 0.36% non-phytate P (NPP), while the treatment groups received diets containing 360 U of exogenous phytase/kg with 0.26% NPP (EP) or 360 phytase U of PTC/kg diet with 0.26% (PTC1), 0.21% (PTC2) or 0.16% (PTC3) NPP. 3. The results showed that there was no significant difference in egg production, average daily feed intake, feed efficiency, rate of broken or soft-shell egg production or egg mass among the treatments. There was no significant difference in eggshell thickness or eggshell strength. On the other hand, no differences in any of the bone variables were found between treatments. The faecal P percentage content in EP, PTC1, PTC2 and PTC3 groups was significantly lower than the control group. 4. In summary, the PTC could be used in the feed of laying hens instead of EP to reduce P excretion without effecting production and bone mineralisation.

Concepts: Food, Glyphosate, Femur, Effect, Genetically modified food, Maize, Transgenic maize, Chicken

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This study was conducted to investigate the association between the metabolic syndrome (MS), which includes a cluster of major risk factors for cardiovascular diseases, and bone mineral density (BMD) from a population-based study. This cross-sectional study was based on a nationwide representative survey data from the Korean National Health and Nutrition Examination Survey (KNHANES) 2008. A total of 3,207 subjects were included from the KNHANES 2008 and composed of men (mean age 48.4 years), premenopausal women (mean age 36.5 years) and postmenopausal women (mean age 64.8 years). The MS was identified according to the new criteria from a joint scientific statement endorsed by major organizations including the National Heart, Lung, and Blood Institute. The mean age of study participants was significantly different according to MS status (58.2 years in the MS group vs. 45.7 years in the non-MS group, P < 0.001). The association between MS and BMD at the lumbar spine and proximal femur was analyzed with adjustment for potential confounders. Although the adjusted BMD at all skeletal sites was not significantly different between participants with and without MS, an increased number of MS components was associated with low adjusted femoral neck (FN) BMD only in men (P = 0.01). After adjusting confounding factors, the triglyceride component of MS was related to low FN BMD in men, but to high BMD at all of the skeletal sites measured in postmenopausal women. The glucose component of MS showed an association with high adjusted BMD at total hip in men. Men with MS had significantly higher odds for pooled osteopenia and osteoporosis (odds ratio: 1.49, 95 % confidence interval: 1.04-2.14). In conclusion, low BMD is associated with MS in Korean men, and the association between the MS component and the BMD is different according to gender.

Concepts: Statistical terminology, Femur, Menopause, Bone, Nutrition, Skeletal system, Epidemiology, Osteoporosis

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This study aimed to investigate the influence of the screw location and plate working length of a locking plate construct at the distal femur on interfragmentary movement under physiological loading.

Concepts: Plate tectonics, Femur