Sample records for metatarsus

  1. A new maniraptoran dinosaur from China with long feathers on the metatarsus

    NASA Astrophysics Data System (ADS)

    Xu, Xing; Zhang, Fucheng


    The unusual presence of long pennaceous feathers on the feet of basal dromaeosaurid dinosaurs has recently been presented as strong evidence in support of the arboreal-gliding hypothesis for the origin of bird flight, but it could be a unique feature of dromaeosaurids and thus irrelevant to the theropod-bird transition. Here, we report a new eumaniraptoran theropod from China, with avian affinities, which also has long pennaceous feathers on its feet. This suggests that such morphology might represent a primitive adaptation close to the theropod-bird transition. The long metatarsus feathers are likely primitive for Eumaniraptora and might have played an important role in the origin of avian flight.

  2. Computed tomography and cross-sectional anatomy of the metatarsus and digits of the one-humped camel (Camelus dromedarius) and buffalo ( Bos bubalis).


    El-Shafey, A; Kassab, A


    The purpose of the present study was to provide a detailed computed tomography (CT) and cross-sectional anatomic reference of the normal metatarsus and digits for the camel and buffalo, as well as to compare between metatarsus and digits in these animals to outstand a basis for diagnosis of their diseases. Advantages, including depiction of detailed cross-sectional anatomy, improved contrast resolution and computer reformatting, make it a potentially valuable diagnostic technique. The hind limbs of 12 healthy adult camel and buffalo were used. Clinically relevant anatomic structures were identified and labelled at each level in the corresponding images (CT and anatomic slices). CT images were used to identify the bony and soft tissue structures of the metatarsus and digits. The knowledge of normal anatomy of the camel and buffalo metatarsus and digits would serve as initial reference to the evaluation of CT images in these species.

  3. Influence of shoes increasing dorsiflexion and decreasing metatarsus flexion on lower limb muscular activity during fitness exercises, walking, and running.


    Bourgit, David; Millet, Guillaume Y; Fuchslocher, Jörg


    The aim of the present study was to compare electromyographic activity during fitness exercises, walking, and running among 3 different dorsiflexion shoes (+2 degrees , +4 degrees , and +10 degrees ) and standard shoes (-4 degrees ). The 3 different dorsiflexion shoes tested in this study have a curvature placed in the middle of the sole. This design was specially projected to decrease the metatarsus flexion. Electromyographic activity of 9 lower limb muscles was measured on 12 healthy female subjects during 5 fitness exercises (unload squat, side and front step, submaximal ballistic plantar flexion, and lunge exercise), and during running (10 km x h(-1)) and walking (4.5 km x h(-1)) on a treadmill. EMG signal was analyzed with the root mean square (RMS) and integrated EMG. All RMS data measured during these exercises were expressed as percentages of maximum voluntary isometric contraction. The results show that dorsiflexion affects muscle recruitment and reorganizes the motor pattern. The general tendency was that the tibialis anterior activity increased with dorsiflexion. However, an optimal dorsiflexion existed for various exercises. It is concluded that shoes with moderate dorsiflexion can activate lower limb muscles differently compared with both standard shoes and shoes with large dorsiflexion during submaximal exercises and locomotion.

  4. Isolated first metatarsocuneiform joint fusion for correction of metatarsus primus varus deformity and literature review.


    Shinabarger, Andrew B; Ryan, Michael T; Dzurik, Matthew; Burns, Patrick R


    Correction of a bunion deformity with the use of proximal first ray procedures has historically included additional distal soft tissue and bone work about the first metatarsophalangeal joint. We report the case of a young adult female who underwent isolated first tarsometatarsal fusion for correction of a bunion deformity. Moreover, we describe the published data related to this approach. This technique could have the potential to improve patient outcomes by avoiding postoperative arthrofibrosis of the first metatarsophalangeal joint.

  5. A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus.


    Hu, Dongyu; Hou, Lianhai; Zhang, Lijun; Xu, Xing


    The early evolution of the major groups of derived non-avialan theropods is still not well understood, mainly because of their poor fossil record in the Jurassic. A well-known result of this problem is the 'temporal paradox' argument that is sometimes made against the theropod hypothesis of avian origins. Here we report on an exceptionally well-preserved small theropod specimen collected from the earliest Late Jurassic Tiaojishan Formation of western Liaoning, China. The specimen is referable to the Troodontidae, which are among the theropods most closely related to birds. This new find refutes the 'temporal paradox'1 and provides significant information on the temporal framework of theropod divergence. Furthermore, the extensive feathering of this specimen, particularly the attachment of long pennaceous feathers to the pes, sheds new light on the early evolution of feathers and demonstrates the complex distribution of skeletal and integumentary features close to the dinosaur-bird transition.


    PubMed Central

    Barrôco, Rui; Nery, Caio; Favero, Gabriela; Mombach, Renan; Nascimento, Oswaldo; Jorge, Silvia; Monteiro, Marina; Diedrichs, Letícia; Abreu, Felipe


    To identify the mean normal length of the metatarsals and the most common metatarsal formulas through a simple measurement method, thereby providing surgeons with data for planning treatment on symptomatic individuals with biometric abnormalities of the foot. Methods: We evaluated and measured dorsoplantar weight-bearing radiographs of normal adult feet (83 males and 83 females). Results: We found relative mean lengths for metatarsus I of 125.4 mm for males and 115.1 mm for females; for metatarsus II, 127.8 mm for males and 117.3 mm for females; for metatarsus III, 123.4 mm for males and 113.5 mm for females; for metatarsus IV, 114.2 mm for males and 105.3 mm for females; for metatarsus V, 99.5 mm for males and 91.7 mm for females. The mean forefoot width was 87.1 mm for males and 80.8 mm for females. Conclusion: Feet with index minus occurred most frequently in both sexes, although all three metatarsal formulas can be considered to be normal patterns. The mean normal pattern for males and females respectively was the following: metatarsus I 2.4 mm and 2.2 mm shorter than metatarsus II; metatarsus III 4.4 mm and 3.8 mm shorter than metatarsus II; metatarsus IV 9.2 mm and 8.2 mm shorter than metatarsus III; metatarsus V 14.7 mm and 13.6 mm shorter than metatarsus IV. PMID:27027034

  7. 50 CFR 21.13 - Permit exceptions for captive-reared mallard ducks.

    Code of Federal Regulations, 2013 CFR


    ... this method shall be the removal of the metacarpal bones of one wing or a portion of the metacarpal bones which renders the bird permanently incapable of flight. (3) Banding of one metatarsus with...

  8. Increased SCE levels in Mediterranean Italian buffaloes affected by limb malformation (transversal hemimelia).


    Peretti, V; Ciotola, F; Albarella, S; Restucci, B; Meomartino, L; Ferretti, L; Barbieri, V; Iannuzzi, L


    In recent years some buffalo farms in Campania have reported the birth of calves with limb malformation, especially with transversal hemimelia. We investigated 20 Mediterranean Italian buffaloes (8 males and 12 females) from one day to six months of age, of which 10 were affected by transversal hemimelia (group 1) and 10 were healthy controls (group 2). The following clinical and radiological patterns were observed in the malformed animals: hind limbs amputated, the right amputated off the second tarsus bones and the left amputated off the proximal epiphysis metatarsus, and the right thoracic limb hypoplasic (1 female); left hind limb amputated off the proximal epiphysis metatarsus (2 females and 1 male); left hind limb amputated off the third tarsus bones (1 female); left hind limb amputated off the tibia (1 female and 1 male); left hind limb amputated off the distal epiphysis metatarsus (1 female); left hind limb amputated off the first phalanx (1 male); right hind limb amputated off the proximal epiphysis metatarsus (1 male). In their malformed limbs all the animals presented more or less developed outlines of claws. The mean rate of SCE/cell in animals with transversal hemimelia was 8.80 +/- 3.19, that of the controls 6.61 +/- 2.73. The difference was statistically significant (P < 0.001).

  9. [The Kramer osteotomy in the treatment of hallux valgus].


    Muminagić, Sahib; Drljevic, Sanja; Granić, Amela; Kapidzić, Tarik; Kovacević, Mehmed; Hodzić, Faruk


    In 1973. J. Kramer published his own technique for the cure of hallux valgus (Orthopädische Praxis Heft 8/1982, 636-645). He corrects bad position of the first bone of the metatarsus with all the consequences which lie in the basis of the deformation. By osteotomy of the first bone of the metatarsus and re-instates functional equipise of the first foot instep in all the components. Having the experience of 550 operated patients he considered that this method has advantages over numerous described method, indicative range is practically wide, respecting the technique it is simply performed, post-operative cure does not require immobilisation, and in comparison with other methods, complications and bad results are practically unknown. On our ward, in the period between 1984 and 1988, we applied Kramer's osteotomy in 98 cases of hallux valgus. The results were satisfying, considerably better than after other methods of hallux valgus treatment.

  10. Single absorbable polydioxanone pin fixation for distal chevron bunion osteotomies.


    Deorio, J K; Ware, A W


    The distal chevron osteotomy is a well-established technique for correction of symptomatic mild to moderate metatarsus primus varus with hallux valgus deformity. Fixation of the osteotomy ranges from none to bone pegs, Kirschner wires, screws, or absorbable pins. We evaluated one surgeon's (J.K.D.) results of distal chevron osteotomy fixation with a single, nonpredrilled, 1.3-mm poly-p-dioxanone pin and analyzed any differences in patients with unilateral or bilateral symptomatic metatarsus primus varus with hallux valgus deformities. All osteotomies healed without evidence of infection, osteolysis, nonunion, or necrosis. Equal correction was achieved in unilateral and bilateral procedures. The technique is quick and easy, and adequate fixation is achieved.

  11. Clarification of the anatomic definition of the bunion deformity.


    Dayton, Paul; Kauwe, Merrell; Feilmeier, Mindi


    Evolution of the terminology applied to the bunion deformity has progressed in parallel with our changing understanding of the deformity itself. Along this path of progression have been multiple terms, sometimes with multiple meanings. Hallux valgus and metatarsus primus varus are 2 of the most common terms for the deformity. Although commonly used, these descriptors can have multiple meanings, and inconsistencies in interpretation can lead to confusion. We propose a more detailed terminology to provide a more accurate description of the entire bunion deformity in 3 planes and for both the hallux and the metatarsal component of the deformity. The term we propose is hallux abducto valgus with metatarsus primus adducto valgus. An accurate understanding of the multiplanar position of the deformed foot is important for planning deformity correction. The descriptors in the terminology proposed will keep in the forefront the aspects of correction required for the first ray and hallux to be returned to an anatomically correct position.

  12. Severe Skew Foot Deformity in a Patient With Freeman-Sheldon Syndrome

    PubMed Central

    Kaissi, Ali Al; Klaushofer, Klaus; Grill, Franz


    We report on a 3-year-old boy with the full phenotypic features of Freeman Sheldon syndrome (FSS). Severe skew foot deformity has been recognized as additional skeletal abnormality. Parents were first degree cousins, raising the possibility of autosomal recessive pattern of inheritance. To the best of our knowledge this is the first report of severe skew foot deformity in a patient with (FSS). Keywords Freeman-Sheldon syndrome; Skew foot deformity; Metatarsus adductus PMID:22383916

  13. New Australovenator hind limb elements pertaining to the holotype reveal the most complete Neovenatorid leg.


    White, Matt A; Benson, Roger B J; Tischler, Travis R; Hocknull, Scott A; Cook, Alex G; Barnes, David G; Poropat, Stephen F; Wooldridge, Sarah J; Sloan, Trish; Sinapius, George H K; Elliott, David A


    We report new skeletal elements pertaining to the same individual which represents the holotype of Australovenator wintonensis, from the 'Matilda Site' in the Winton Formation (Upper Cretaceous) of western Queensland. The discovery of these new elements means that the hind limb of Australovenator is now the most completely understood hind limb among Neovenatoridae. The new hind limb elements include: the left fibula; left metatarsal IV; left pedal phalanges I-2, II-1, III-4, IV-2, IV-3; and right pedal phalanges, II-2 and III-1. The detailed descriptions are supported with three dimensional figures. These coupled with the completeness of the hind limb will increase the utility of Australovenator in comparisons with less complete neovenatorid genera. These specimens and the previously described hind limb elements of Australovenator are compared with other theropods classified as neovenatorids (including Neovenator, Chilantaisaurus, Fukuiraptor, Orkoraptor and Megaraptor). Hind limb length proportion comparisons indicate that the smaller neovenatorids Australovenator and Fukuiraptor possess more elongate and gracile hind limb elements than the larger Neovenator and Chilantaisaurus. Greater stride lengths to body size exist in both Fukuiraptor and Australovenator with the femur discovered to be proportionally shorter the rest of the hind limb length. Additionally Australovenator is identified as possessing the most elongate metatarsus. The metatarsus morphology varies with body size. The larger neoventorids possess a metatarsus with greater width but shorter length compared to smaller forms.

  14. New Australovenator Hind Limb Elements Pertaining to the Holotype Reveal the Most Complete Neovenatorid Leg

    PubMed Central

    White, Matt A.; Benson, Roger B. J.; Tischler, Travis R.; Hocknull, Scott A.; Cook, Alex G.; Barnes, David G.; Poropat, Stephen F.; Wooldridge, Sarah J.; Sloan, Trish; Sinapius, George H. K.; Elliott, David A.


    We report new skeletal elements pertaining to the same individual which represents the holotype of Australovenator wintonensis, from the ‘Matilda Site’ in the Winton Formation (Upper Cretaceous) of western Queensland. The discovery of these new elements means that the hind limb of Australovenator is now the most completely understood hind limb among Neovenatoridae. The new hind limb elements include: the left fibula; left metatarsal IV; left pedal phalanges I-2, II-1, III-4, IV-2, IV-3; and right pedal phalanges, II-2 and III-1. The detailed descriptions are supported with three dimensional figures. These coupled with the completeness of the hind limb will increase the utility of Australovenator in comparisons with less complete neovenatorid genera. These specimens and the previously described hind limb elements of Australovenator are compared with other theropods classified as neovenatorids (including Neovenator, Chilantaisaurus, Fukuiraptor, Orkoraptor and Megaraptor). Hind limb length proportion comparisons indicate that the smaller neovenatorids Australovenator and Fukuiraptor possess more elongate and gracile hind limb elements than the larger Neovenator and Chilantaisaurus. Greater stride lengths to body size exist in both Fukuiraptor and Australovenator with the femur discovered to be proportionally shorter the rest of the hind limb length. Additionally Australovenator is identified as possessing the most elongate metatarsus. The metatarsus morphology varies with body size. The larger neoventorids possess a metatarsus with greater width but shorter length compared to smaller forms. PMID:23894328

  15. The earliest known sauropod dinosaur and the first steps towards sauropod locomotion.


    Yates, Adam M; Kitching, James W


    A partial dinosaur skeleton from the Upper Triassic (Norian) sediments of South Africa is described and named Antetonitrus ingenipes. It provides the first informative look at a basal sauropod that was beginning to show adaptations towards graviportal quadrupedalism such as an elongated forelimb, a modified femoral architecture, a shortened metatarsus and a changed distribution of weight across the foot. These adaptations allowed the clade to produce the largest-ever terrestrial animals. However, A. ingenipes lacked specializations of the hand found in more derived sauropods that indicate it retained the ability to grasp. Antetonitrus is older than the recently described Isanosaurus from Thailand and is the oldest known definitive sauropod.

  16. The earliest known sauropod dinosaur and the first steps towards sauropod locomotion.

    PubMed Central

    Yates, Adam M; Kitching, James W


    A partial dinosaur skeleton from the Upper Triassic (Norian) sediments of South Africa is described and named Antetonitrus ingenipes. It provides the first informative look at a basal sauropod that was beginning to show adaptations towards graviportal quadrupedalism such as an elongated forelimb, a modified femoral architecture, a shortened metatarsus and a changed distribution of weight across the foot. These adaptations allowed the clade to produce the largest-ever terrestrial animals. However, A. ingenipes lacked specializations of the hand found in more derived sauropods that indicate it retained the ability to grasp. Antetonitrus is older than the recently described Isanosaurus from Thailand and is the oldest known definitive sauropod. PMID:12965005

  17. Percutaneous sagittal plane closing wedge osteotomy of the first metatarsal.


    Lui, Tun Hing


    Osteotomy of the first metatarsal in the sagittal plane is useful in correction of numerous deformity of the foot. Plantarflexion osteotomy of the first metatarsal can be used to treat hallux rigidus, hallux limitus, forefoot varus in flatfoot deformity and iatrogenic metatarsus primus elevates. Dorsiflexion osteotomy of the first metatarsal is an important component in surgical correction of pes cavus. It is also indicated in recalcitrant diabetic neuropathic ulcers at the first metatarsal head. We described a minimally invasive technique of sagittal plane corrective osteotomy of the first metatarsal, which can be either a plantarflexion or dorsiflexion one.

  18. Spider joint hair sensilla: adaptation to proprioreceptive stimulation.


    Schaber, Clemens F; Barth, Friedrich G


    Adding to previous efforts towards a better understanding of the remarkable diversity of spider mechanosensitive hair sensilla, this study examines hairs of Cupiennius salei most likely serving a proprioreceptive function. At the tibia-metatarsus joint of all walking legs, there are two opposing groups of hairs ventrally on the tibia (20 hairs) and metatarsus (75 hairs), respectively. These hairs deflect each other when the joint flexes during locomotion, reversibly interlocking by microtrichs on their hair shafts. The torque resisting the hair deflection into the direction of natural stimulation is smaller by up to two powers of ten than that for the other directions. The torsional restoring constant S of the hair suspension is about 10(-10) Nm rad(-1) in the preferred direction, up to a hair deflection angle of 30° (mean of natural deflection angles). Joint movements were imposed in ranges and at rates measured in walking spiders and sensory action potentials recorded. Within the natural step frequencies (0.3-3 Hz) the rate of action potentials follows the velocity of hair deflection. All findings point to the morphological, mechanical, and physiological adaptedness of the joint hair sensilla to their proprioreceptive stimulation during locomotion.

  19. Short-term Outcomes of Induced Membrane Technique in Treatment of Long Bone Defects in Iran

    PubMed Central

    Yeganeh, Ali; Mahmodi, Mani; Farahini, Hosein; Moghtadaei, Mehdi


    Introduction: Severe defects in long bones can be caused by several factors such as trauma that lead to open wound and secondary infections after surgery. Induced membrane technique is one of the therapeutic strategies that can be used for these patients. Due to importance of this method and lack of information about this technique in Iran. Aim: this study was performed to investigate technical strengths and weakness of induced membrane technique. Material and Methods: This case series study conducted on 21 patients with bone defects in the femur and tibia and metatarsal bones referred to orthopedic clinic of Rasoul Akram Hospital, Tehran, Iran, for induced membrane surgery in 2012-2015. Demographic and clinical data were obtained using history, clinical examinations and observations for each patient. Union achievement was the main outcome of this study, which was confirmed by radiographic findings and physical examination. Obtained data was analyzed by SPSS ver. 16. Results: All patients were male except one and their mean age was 30.52 years old. Bone defects were in tibia, femur and metatarsus in 9, 9 and 3 patients, respectively. Three patients received soft tissue reconstruction with flap before induced membrane surgery. Age, defects size, cigarette addiction and drug use and delay to start the treatment had no significant effect on union status. In total, 90% of patients had successful surgery. Conclusion: using induced membrane technique in patients with defects in their long bone such as tibia, femur and metatarsus would lead to high success for reconstruction. PMID:27703290

  20. The use of a circular external skeletal fixation device for the management of long bone osteotomies in large ruminants: an experimental study.


    Aithal, H P; Singh, G R; Hoque, M; Maiti, S K; Kinjavdekar, P; Pawde, A M; Setia, H C


    The study was undertaken to evaluate the feasibility of a simple, inexpensive model of circular external fixator (CEF) for use in large ruminants. A simple model of CEF frames consisting of four full rings (13-19 cm diameter, 4 cm wide and 4 mm thick with 18-24 holes) connected by threaded rods (8 mm diameter, 10-15 cm long) and nuts was developed using mild (low carbon) steel and were nickel-plated. In the first phase of the study, three male cow calves were utilized to study the feasibility of application of the fixators in the metatarsus, tibia and radius, in reference of adaptation and tolerance by animals. In the second phase, the fixators were tested in osteotomized bones. Six bull calves of 1.5-2 years of age weighing about 200-250 kg were utilized for this purpose. After preparing the area for aseptic surgery, under xylazine (at 0.1 mg/kg, i.m.)-ketamine (i.v. till effect) general anaesthesia, the test bone (metatarsus, radius and tibia in two animals each) was approached through the medial surface and an osteotomy was created with a saw and chisel at the mid-diaphysis. The pre-constructed 4-ring CEF was mounted on the limb around the test bone in such a way that it formed a cylinder with the axis of the limb at the centre. Each ring was then fixed to the bone with a pair of beaded wires (316 SS) of 3.5 mm diameter. During the post-operative period, the animals were observed for any change in behaviour, tolerance of the fixators, the weight bearing on the test limb, the status of the fixator, and the level of reduction of the osteotomy, alignment and healing at different intervals. The fixation of CEF was easier in the metatarsus and radius than in the tibia. The inner ring diameters found adequate for metatarsus, radius and tibia were 13-15 cm, 15-17 cm and 17-19 cm, respectively. The fixators applied to different bones were well-tolerated, and the animals could lay down, stand and walk freely with the fixator without any problems. All the animals showed

  1. Orthopaedic implications of multiple gestation pregnancy with triplets.


    Bielski, Robert J; Gesell, Mark W; Teng, Andelle L; Cooper, Daniel H; Muraskas, Jonathan K


    Intrauterine crowding has been implicated as a risk factor in several orthopaedic conditions, such as developmental dysplasia of the hip (DDH), metatarsus adductus, and torticollis. The goal of this study was to see whether orthopaedic conditions associated with intrauterine crowding were more frequent in multiple gestation pregnancies, specifically in triplets. The authors reviewed their experience over a 10-year period with 261 children who were products of triplet pregnancies. They surveyed 13 orthopaedic conditions and found only one condition, torticollis, that had a greater incidence than that reported in single gestation pregnancies. A 0% incidence of DDH was found in these patients. Routine ultrasound screening cannot be recommended in these patients based on these results.

  2. Growth and development of tarsal and metatarsal bones in successfully treated congenital idiopathic clubfoot: early radiographic study.


    Segev, Eitan; Yavor, Ariela; Ezra, Eli; Hemo, Yoram


    Fifteen cases of unilateral clubfoot treated according to Ponseti's technique had the talocalcaneal angles on the anteroposterior and lateral views and the size of the talus, calcaneus, I-V metatarsus measured on radiographs of both feet that were taken at a mean age of 15.2 months (range 8-23). The measurements of talocalcaneal angles and size of the talus, calcaneus, and I, II, and III metatarsi were significantly smaller on the affected side, whereas the values for the IV and V metatarsi were similar on both sides. Clubfoot deformity involves all structures of the foot, but intrinsic compressive forces on the small hindfoot bones induce measurable reduction in their size and spatial orientation. This effect is seen early on the medial but not the lateral long tubular forefoot bones.

  3. Three new species of Misionella from northern Brazil (Araneae, Haplogynae, Filistatidae)

    PubMed Central

    Brescovit, Antonio D.; Magalhaes, Ivan L. F.; Cizauskas, Igor


    Abstract Three new species of the genus Misionella are described from Brazil: Misionella carajas sp. n. and Misionella aikewara sp. n. from caves in the states of Pará and Tocantins and Misionella pallida sp. n. from natural and synanthropic dry areas in the states of Piauí, Maranhão, Rio Grande do Norte and Bahia. These species seem to belong to a distinct group within the genus; the males have an elongate palpal tibia and bulb, a pair of characteristic and hirsute macrosetae in the second metatarsus and the females have internal genitalia with only one pair of spermathecae, with relatively short ducts, lacking the auxiliary receptacles. Their phylogenetic placement and geographic distribution are briefly discussed. PMID:27408535

  4. [Valid constructing method of three-dimensional finite element human foot model and experimental analysis on its rationality].


    Niu, Wenxin; Yang, Yunfeng; Yu, Guangrong; Ding, Zuquan


    To provide a digital simulation platform for foot-ankle biomechanics research, a 3-D finite element model was established through helical CT images under the principle of RE (reverse engineering) and meshed in FEM software. In the process of modeling cartilage, ligaments, tendons and plantar soft tissue, many anatomic data and results of cadaver specimen experiment were referenced; LINE elements and SHELL elements were used skillfully to simplify the model and resemble the physiological state. The model was then validated by specimen experimentation, which was done on seven fresh cadaver foot specimens, and digital speckle correlation method (DSCM) was used to measure their displacements. Upon the comparison with experimentation and others models, this study also testified that the model, of which the plantar fascia is linked to the heads of metatarsus, is more reasonable to clinical application.

  5. The phylogenetic position of the Tyrannosauridae: implications for theropod systematics

    USGS Publications Warehouse

    Holtz, T.R.


    A new cladistic analysis indicates that the tyrannosaurs were derived members of the Coelurosauria, a group of otherwise small theropods. Desipte certain gross cranial similarities with the large predators of the Jurassic and Early Cretaceous, the Late Cretaceous tyrannosaurids are shown to be the sister group to ornithominids and troodontids, which share a derived condition of the metatarsus. The taxa "Carnosauria' and "Deinonychosauria' are shown to be polyphyletic, and the Late Jurassic African form Elaphrosaurus is found to be the sister taxon to Abelisauridae. Purported allosaurid-tyrannosaurid synapomorphies are seen to be largely size-related. The remaining giant tetanurine theropods were found to be progressive distant outgroups to an allosaurid-coelurosaur clade. -from Author

  6. Contribution of plantar pressure to the prevention and quantification of the muscle-skeletal injury risk in hiking trails--a pilot study.


    Gabriel, Ronaldo; Monteiro, Marco; Moreira, Helena; Maia, Miguel


    Hiking trails have been growing in popularity in the health and well-being promotion. Consequently, the foot became an object of study in order to understand the discomfort and pain in the lower limb. The aims of the work were: 1) to detect tendencies for behaviour of maximum values of plantar pressure (MaxP) during the walk on different slopes, 2) to contribute to the methodology of the difficulty level of hiking trails. Equations show strong tendencies (R2 > 0.8) of behaviour of MaxP in the lateral zones of the heel, 4th and 5th metatarsus as well as in the plantar zone of the hallux. The analysis of the difficulty level of the hiking trails branches deserves a separate presentation, including the technical difficulty analysis (with a compulsory emphasis on the biomechanics) and information on the caloric consumption and on the slopes of each branch.

  7. Evaluation of Relative Bioavailability of 25-Hydroxycholecalciferol to Cholecalciferol for Broiler Chickens

    PubMed Central

    Han, J. C.; Chen, G. H.; Wang, J. G.; Zhang, J. L.; Qu, H. X.; Zhang, C. M.; Yan, Y. F.; Cheng, Y. H.


    This study was conducted to evaluate the relative bioavailability (RBV) of 25-hydroxycholecalciferol (25-OH-D3) to cholecalciferol (vitamin D3) in 1- to 21-d-old broiler chickens fed with calcium (Ca)- and phosphorus (P)-deficient diets. On the day of hatch, 450 female Ross 308 broiler chickens were assigned to nine treatments, with five replicates of ten birds each. The basal diet contained 0.50% Ca and 0.25% non-phytate phosphorus (NPP) and was not supplemented with vitamin D. Vitamin D3 was fed at 0, 2.5, 5.0, 10.0, and 20.0 μg/kg, and 25-OH-D3 was fed at 1.25, 2.5, 5.0, and 10.0 μg/kg. The RBV of 25-OH-D3 was determined using vitamin D3 as the standard source by the slope ratio method. Vitamin D3 and 25-OH-D3 intake was used as the independent variable for regression analysis. The linear relationships between the level of vitamin D3 or 25-OH-D3 and body weight gain (BWG) and the weight, length, ash weight, and the percentage of ash, Ca, and P in femur, tibia, and metatarsus of broiler chickens were observed. Using BWG as the criterion, the RBV value of 25-OH-D3 to vitamin D3 was 1.85. Using the mineralization of the femur, tibia, and metatarsus as criteria, the RBV of 25-OH-D3 to vitamin D3 ranged from 1.82 to 2.45, 1.86 to 2.52, and 1.65 to 2.05, respectively. These data indicate that 25-OH-D3 is approximately 2.03 times as active as vitamin D3 in promoting growth performance and bone mineralization in broiler chicken diets. PMID:26954155

  8. Functional aspects of metatarsal head shape in humans, apes, and Old World monkeys.


    Fernández, Peter J; Almécija, Sergio; Patel, Biren A; Orr, Caley M; Tocheri, Matthew W; Jungers, William L


    Modern human metatarsal heads are typically described as "dorsally domed," mediolaterally wide, and dorsally flat. Despite the apparent functional importance of these features in forefoot stability during bipedalism, the distinctiveness of this morphology has not been quantitatively evaluated within a broad comparative framework. In order to use these features to reconstruct fossil hominin locomotor behaviors with any confidence, their connection to human bipedalism should be validated through a comparative analysis of other primates with different locomotor behaviors and foot postures, including species with biomechanical demands potentially similar to those of bipedalism (e.g., terrestrial digitigrady). This study explores shape variation in the distal metatarsus among humans and other extant catarrhines using three-dimensional geometric morphometrics (3 DGM). Shape differences among species in metatarsal head morphology are well captured by the first two principal components of Procrustes shape coordinates, and these two components summarize most of the variance related to "dorsal doming" and "dorsal expansion." Multivariate statistical tests reveal significant differences among clades in overall shape, and humans are reliably distinguishable from other species by aspects of shape related to a greater degree of dorsal doming. Within quadrupeds, terrestrial species also trend toward more domed metatarsal heads, but not to the extent seen in humans. Certain aspects of distal metatarsus shape are likely related to habitual dorsiflexion of the metatarsophalangeal joints, but the total morphological pattern seen in humans is distinct. These comparative results indicate that this geometric morphometric approach is useful to characterize the complexity of metatarsal head morphology and will help clarify its relationship with function in fossil primates, including early hominins.

  9. Scaling of the appendicular skeleton of the giraffe (Giraffa camelopardalis).


    van Sittert, Sybrand; Skinner, John; Mitchell, Graham


    Giraffes have remarkably long and slender limb bones, but it is unknown how they grow with regard to body mass, sex, and neck length. In this study, we measured the length, mediolateral (ML) diameter, craniocaudal (CC) diameter and circumference of the humerus, radius, metacarpus, femur, tibia, and metatarsus in 10 fetuses, 21 females, and 23 males of known body masses. Allometric exponents were determined and compared. We found the average bone length increased from 340 ± 50 mm at birth to 700 ± 120 mm at maturity, while average diameters increased from 30 ± 3 to 70 ± 11 mm. Fetal bones increased with positive allometry in length (relative to body mass) and in diameter (relative to body mass and length). In postnatal giraffes bone lengths and diameters increased iso- or negatively allometric relative to increases in body mass, except for the humerus CC diameter which increased with positive allometry. Humerus circumference also increased with positive allometry, that of the radius and tibia isometrically and the femur and metapodials with negative allometry. Relative to increases in bone length, both the humerus and femur widened with positive allometry. In the distal limb bones, ML diameters increased isometrically (radius, metacarpus) or positively allometric (tibia, metatarsus) while the corresponding CC widths increased with negative allometry and isometrically, respectively. Except for the humerus and femur, exponents were not significantly different between corresponding front and hind limb segments. We concluded that the patterns of bone growth in males and females are identical. In fetuses, the growth of the appendicular skeleton is faster than it is after birth which is a pattern opposite to that reported for the neck. Allometric exponents seemed unremarkable compared to the few species described previously, and pointed to the importance of neck elongation rather than leg elongation during evolution. Nevertheless, the front limb bones

  10. The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

    NASA Astrophysics Data System (ADS)

    Aygün, Ali; Narinç, Doǧan


    Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

  11. Rear-foot, mid-foot and fore-foot motion during the stance phase of gait.


    Leardini, A; Benedetti, M G; Berti, L; Bettinelli, D; Nativo, R; Giannini, S


    This paper proposes a new protocol designed to track a large number of foot segments during the stance phase of gait with the smallest possible number of markers, with particular clinical focus on coronal plane alignment of the rear-foot, transverse and sagittal plane alignment of the metatarsal bones, and changes at the medial longitudinal arch. The shank, calcaneus, mid-foot and metatarsus were assumed to be 3D rigid bodies. The longitudinal axis of the first, second and fifth metatarsal bones and the proximal phalanx of the hallux were also tracked independently. Skin markers were mounted on bony prominences or joint lines, avoiding the course of main tendons. Trajectories of the 14 markers were collected by an eight-camera motion capture system at 100 Hz on a population of 10 young volunteers. Three-dimensional joint rotations and planar angles were calculated according to anatomically based reference frames. The marker set was well visible throughout the stance phase of gait, even in a camera configuration typical of gait analysis of the full body. The time-histories of the joint rotations and planar angles were well repeatable among subjects and consistent with clinical and biomechanical knowledge. Several dynamic measurements were originally taken, such as elevation/drop of the medial longitudinal arch and of three metatarsal bones, rear-foot to fore-foot rotation and transverse plane deformation of the metatarsus. The information obtained from this protocol, consistent with previous clinical knowledge, enhanced our understanding of the dynamics of the human foot during stance.

  12. First ancient DNA sequences from the Late Pleistocene red deer (Cervus elaphus) in the Crimea, Ukraine

    NASA Astrophysics Data System (ADS)

    Stanković, Ana; Nadachowski, Adam; Doan, Karolina; Stefaniak, Krzysztof; Baca, Mateusz; Socha, Paweł; Wegleński, Piotr; Ridush, Bogdan


    The Late Pleistocene has been a period of significant population and species turnover and extinctions among the large mammal fauna. Massive climatic and environmental changes during Pleistocene significantly influenced the distribution and also genetic diversity of plants and animals. The model of glacial refugia and habitat contraction to southern peninsulas in Europe as areas for the survival of temperate animal species during unfavourable Pleistocene glaciations is at present widely accepted. However, both molecular data and the fossil record indicate the presence of northern and perhaps north-eastern refugia in Europe. In recent years, much new palaeontological data have been obtained in the Crimean Peninsula, Ukraine, following extensive investigations. The red deer (Cervus elaphus) samples for aDNA studies were collected in Emine-Bair-Khosar Cave, situated on the north edge of Lower Plateau of the Chatyrdag Massif (Crimean Mountains). The cave is a vertical shaft, which functioned as a huge mega-trap over a long period of time (probably most of the Pleistocene). The bone assemblages provided about 5000 bones belonging to more than 40 species. The C. elaphus bones were collected from three different stratigraphical levels, radiocarbon dated by accelerator mass spectrometry (AMS) method. The bone fragments of four specimens of red deer were used for the DNA isolation and analysis. The mtDNA (Cytochome b) was successfully isolated from three bone fragments and the cytochrome b sequences were amplified by multiplex PCR. The sequences obtained so far allowed for the reconstruction of only preliminary phylogenetic trees. A fragment of metatarsus from level dated to ca. 48,500±2,000 years BP, yielded a sequence of 513 bp, allowing to locate the specimen on the phylogenetic tree within modern C. elaphus specimens from southern and middle Europe. The second bone fragment, a fragment of mandible, collected from level dated approximately to ca. 33,500±400 years BP

  13. Determining age and sex of American coots

    USGS Publications Warehouse

    Eddleman, William R.; Knopf, Fritz L.


    Reliable techniques for age and sex determination of migrating and wintering American Coots (Fulica americana) have not been available. Breeding coots can be ages through age 3 by tarsal color (birds 4 years and older were placed in a 4+ age class) (Crawford 1978), and males and females have sex-specific behaviors and calls while on breeding territories (Gullion 1950, 1952). Externally, juvenile coots differ from adults in having gray (as opposed to white) bills and brown (as opposed to red) eyes to an age of 75 days (Gullion 1954-394). Bill color changes to white by about 120 days. No quantitative data have been available, however, on the proportion of juveniles retaining these traits throughout fall and early winter. Nonbreeding coots can be ages as juvenile or adult by internal examination of the thickness of the wall of the bursa of Fabricius, although bursal depth does not predictably decline with age (Fredrickson 1968). Attempts to sex coots by single external measurements of combinations of measurements have met with mixed success. Eight-five percent of 101 fall migrants in Wisconsin could be sexed by the length of the metatarsus-midtoe including claw by using 139.5 mm as a cutoff point (Burton 1959), whereas 88% of 67 coots in California were correctly sexed by the length of the metatarsus-midtoe without claw using 127.5 mm as the cutoff point (Gullion 1952). Two-hundred-thirty-two of 291 coots collected in Iowa, however, were in the zone of overlap between the sexes for this measurement (Fredrickson 1968). Previous studies attempting to develop aging and sexing techniques for American Coots have been limited to a few study sites or to 1 season or year, often failing to take geographical, annual, and seasonal morphological variation into account (e.g., Visser 1976, Fjeldsa 1977). We designed the present study to refine and quantify external and internal age and sex criteria for postbreeding coots, with the objective of defining techniques applicable for all

  14. A gigantic new dinosaur from Argentina and the evolution of the sauropod hind foot.


    González Riga, Bernardo J; Lamanna, Matthew C; Ortiz David, Leonardo D; Calvo, Jorge O; Coria, Juan P


    Titanosauria is an exceptionally diverse, globally-distributed clade of sauropod dinosaurs that includes the largest known land animals. Knowledge of titanosaurian pedal structure is critical to understanding the stance and locomotion of these enormous herbivores and, by extension, gigantic terrestrial vertebrates as a whole. However, completely preserved pedes are extremely rare among Titanosauria, especially as regards the truly giant members of the group. Here we describe Notocolossus gonzalezparejasi gen. et sp. nov. from the Upper Cretaceous of Mendoza Province, Argentina. With a powerfully-constructed humerus 1.76 m in length, Notocolossus is one of the largest known dinosaurs. Furthermore, the complete pes of the new taxon exhibits a strikingly compact, homogeneous metatarsus--seemingly adapted for bearing extraordinary weight--and truncated unguals, morphologies that are otherwise unknown in Sauropoda. The pes underwent a near-progressive reduction in the number of phalanges along the line to derived titanosaurs, eventually resulting in the reduced hind foot of these sauropods.

  15. Functional limits of agreement applied as a novel method comparison tool for accuracy and precision of inertial measurement unit derived displacement of the distal limb in horses.


    Olsen, Emil; Pfau, Thilo; Ritz, Christian


    Over ground motion analysis in horses is limited by a small number of strides and restraints of the indoor gait laboratory. Inertial measurement units (IMUs) are transforming the knowledge of human motion and objective clinical assessment through the opportunity to obtain clinically relevant data under various conditions. When using IMUs on the limbs of horses to determine local position estimates, conditions with high dynamic range of both accelerations and rotational velocities prove particularly challenging. Here we apply traditional method agreement and suggest a novel method of functional data analysis to compare motion capture with IMUs placed over the fetlock joint in seven horses. We demonstrate acceptable accuracy and precision at less than or equal to 5% of the range of motion for detection of distal limb mounted cranio-caudal and vertical position. We do not recommend the use of the latero-medial position estimate of the distal metacarpus/metatarsus during walk where the average error is 10% and the maximum error 111% of the range. We also show that functional data analysis and functional limits of agreement are sensitive methods for comparison of cyclical data and could be applied to differentiate changes in gait for individuals across time and conditions.

  16. Altitude, pasture type, and sheep breed affect bone metabolism and serum 25-hydroxyvitamin D in grazing lambs.


    Willems, Helen; Leiber, Florian; Kohler, Martina; Kreuzer, Michael; Liesegang, Annette


    This study aimed to investigate the bone development of two mountain sheep breeds during natural summer grazing either in the lowlands or on different characteristic alpine pastures. Pasture types differed in topographic slope, plant species composition, general nutritional feeding value, Ca and P content, and Ca:P ratio of herbage. Twenty-seven Engadine sheep (ES) lambs and 27 Valaisian Black Nose sheep (VS) lambs were divided into four groups of 6 to 7 animals per breed and allocated to three contrasting alpine pasture types and one lowland pasture type. The lambs were slaughtered after 9 wk of experimental grazing. The steep alpine pastures in combination with a high (4.8) to very high (13.6) Ca:P ratio in the forage decreased total bone mineral content as measured in the middle of the left metatarsus of the lambs from both breeds, and cortical bone mineral content and cortical bone mineral density of ES lambs. Breed × pasture type interactions occurred in the development of total and cortical bone mineral content, and in cortical thickness, indicating that bone metabolism of different genotypes obviously profited differently from the varying conditions. An altitude effect occurred for 25-hydroxyvitamin D with notably higher serum concentrations on the three alpine sites, and a breed effect led to higher concentrations for ES than VS. Despite a high variance, there were pasture-type effects on serum markers of bone formation and resorption.

  17. Effects of inducible nitric oxide synthase blockade within the periaqueductal gray on cardiovascular responses during mechanical, heat, and cold nociception.


    Chaitoff, Kevin A; Toner, Francis; Tedesco, Anthony; Maher, Timothy J; Ally, Ahmmed


    We have examined the role of inducible nitric oxide synthase (iNOS) within the dorsolateral periaqueductal gray mater (dlPAG) on cardiovascular responses during mechanical, thermal, and cold nociception in anesthetized rats. Mechanical stimulus was applied by a unilateral hindpaw pinch for 10 s that increased mean arterial pressure (MAP) and heart rate (HR). Bilateral microdialysis of a selective iNOS inhibitor, aminoguanidine (AGN; 10 μM), into the dlPAG for 30 min augmented MAP and HR responses during a mechanical stimulation. The cardiovascular responses recovered following discontinuation of the drug. Heat stimulus was generated by immersing one hindpaw metatarsus in a water bath at 52°C for 10 s, and this increased MAP and HR. Administration of AGN into the PAG potentiated these cardiovascular responses. Cardiovascular responses recovered following discontinuation of the drug. In contrast, application of a cold stimulus by immersing one hindpaw at 10°C for 10 s resulted in depressor and bradycardic responses. A second cold stimulus resulted in a response that was not significantly different from that prior to or after recovery from the AGN infusion. These results demonstrate that iNOS within the dlPAG plays a differential role in modulating cardiovascular responses during mechanical-, heat-, and cold-mediated nociception.

  18. Is our current paradigm for evaluation and management of the bunion deformity flawed? A discussion of procedure philosophy relative to anatomy.


    Dayton, Paul; Kauwe, Merrell; Feilmeier, Mindi


    Of the >100 procedures that have been proposed to treat hallux valgus or the "bunion" deformity, most have focused on correction through metatarsal osteotomies at various levels combined with soft tissue balancing procedures at the first metatarsophalangeal joint. This paradigm of metatarsal osteotomy and soft tissue balancing has been so commonplace, any argument for a fundamental change to the approach becomes uncomfortable and seems unwarranted to most foot and ankle surgeons. However, the simple fact that so many procedures exist, with so many modifications of these procedures, can be interpreted as a failure of our basic paradigm of metatarsal osteotomy and soft tissue balancing. We have observed that failure to recognize frontal plane rotation of the first metatarsal and our willingness to ignore deformity correction principles and create osteotomies outside the center of rotation of angulation are factors that can result in inconsistent outcomes. Our current multiprocedural mindset drives the search for yet more procedures and modifications in an attempt to reduce the incidence of complications. We present an anatomic analysis of hallux abducto valgus and metatarsus primus adducto valgus and critically analyze some of the shortcomings of currently popular corrective procedures. We also review the available data regarding frontal plane rotation of the first metatarsal and propose a new paradigm that considers frontal plane rotation of the first metatarsal as a priority in choosing the most appropriate procedure for bunion correction.

  19. Identifying sex and age of apapane and iiwi on Hawaii

    USGS Publications Warehouse

    Fancy, S.G.; Pratt, T.K.; Lindsey, G.D.; Harada, C.K.; Parent, A.H.; Jacobi, J.D.


    Methods to determine the sex and age of Apapane (Himatione sanguinea) and Iiwi (Vestiaria coccinea) were developed on the basis of 189 museum specimens and 91 live birds captured in mist nets on the Island of Hawaii (USA). Both species retain all juvenal primaries and some juvenal secondaries and body feathers after the first prebasic molt and attain full adult plumage after the second prebasic molt. Apapane in their first basic plumage retain some buff-edged juvenal secondaries (particularly secondaries five and six) and sometimes retain a few gray-brown feathers on the head. The first basic plumage of Iiwi is characterized by secondaries 6-9 being longer and darker than secondaries 1-4 and the presence of a few yellowish juvenal body feathers with black spots at the tips. Adult male Apapane and Iiwi have longer wing, tail, exposed culmen, culmen and tarso-metatarsus lengths than females. Linear discriminant functions are presented to sex adult Apapane and Iiwi from lengths of their wing chord and exposed culmen.

  20. Cribellate thread production in spiders: Complex processing of nano-fibres into a functional capture thread.


    Joel, Anna-Christin; Kappel, Peter; Adamova, Hana; Baumgartner, Werner; Scholz, Ingo


    Spider silk production has been studied intensively in the last years. However, capture threads of cribellate spiders employ an until now often unnoticed alternative of thread production. This thread in general is highly interesting, as it not only involves a controlled arrangement of three types of threads with one being nano-scale fibres (cribellate fibres), but also a special comb-like structure on the metatarsus of the fourth leg (calamistrum) for its production. We found the cribellate fibres organized as a mat, enclosing two parallel larger fibres (axial fibres) and forming the typical puffy structure of cribellate threads. Mat and axial fibres are punctiform connected to each other between two puffs, presumably by the action of the median spinnerets. However, this connection alone does not lead to the typical puffy shape of a cribellate thread. Removing the calamistrum, we found a functional capture thread still being produced, but the puffy shape of the thread was lost. Therefore, the calamistrum is not necessary for the extraction or combination of fibres, but for further processing of the nano-scale cribellate fibres. Using data from Uloborus plumipes we were able to develop a model of the cribellate thread production, probably universally valid for cribellate spiders.

  1. A dynamic model of the windlass mechanism of the foot: evidence for early stance phase preloading of the plantar aponeurosis.


    Caravaggi, Paolo; Pataky, Todd; Goulermas, John Y; Savage, Russel; Crompton, Robin


    In the present study we have estimated the temporal elongation of the plantar aponeurosis (PA) during normal walking using a subject-specific multi-segment rigid-body model of the foot. As previous studies have suggested that muscular forces at the ankle can pre-load the PA prior to heel-strike, the main purpose of the current study was to test, through modelling, whether there is any tension present in the PA during early stance phase. Reflective markers were attached to bony landmarks to track the kinematics of the calcaneus, metatarsus and toes during barefoot walking. Ultrasonography measurements were performed on three subjects to determine both the location of the origin of the PA on the plantar aspect of the calcaneus, and the radii of the metatarsal heads. Starting with the foot in a neutral, unloaded position, inverse kinematics allowed calculation of the tension in the five slips of the PA during the whole duration of the stance phase. The results show that the PA experienced tension significantly above rest during early stance phase in all subjects (P<0.01), thus providing support for the PA-preloading hypothesis. The amount of preloading and the maximum elongation of the slips of the PA decreased from medial to lateral. The mean maximum tension exerted by the PA was 1.5 BW (body weight) over the three subjects.

  2. The first dromaeosaurid (Dinosauria: Theropoda) from the Lower Cretaceous Bayan Gobi Formation of Nei Mongol, China

    PubMed Central

    Pei, Rui; Tan, Qingwei; Xu, Xing


    The first dromaeosaurid theropod from the Lower Cretaceous Bayan Gobi Formation is identified based on an incompletely preserved partially-articulated left leg, increasing the known diversity of its understudied ecosystem. The leg belongs to specimen IVPP V22530 and includes a typical deinonychosaurian pedal phalanx II-2 with a distinct constriction between the enlarged proximal end and the distal condyle as well as a typical deinonychosaurian enlarged pedal phalanx II-3. It possesses a symmetric metatarsus and a slender and long MT V that together suggest it is a dromaeosaurid. Two anatomical traits suggest the leg is microraptorine-like, but a more precise taxonomic referral was not possible: metatarsals II, III and IV are closely appressed distally and the ventral margin of the medial ligament pit of phalanx II-2 is close to the centre of the rounded distal condyle. This taxonomic status invites future efforts to discover additional specimens at the study locality because—whether it is a microraptorine or a close relative—this animal is expected to make important contributions to our understanding of dromaeosaurid evolution and biology. IVPP V22530 also comprises of an isolated dromaeosaurid manual ungual, a proximal portion of a right theropod anterior dorsal rib and an indeterminate bone mass that includes a collection of ribs. Neither the rib fragment nor the bone mass can be confidently referred to Dromaeosauridae, although they may very well belong to the same individual to whom the left leg belongs. PMID:26664809

  3. Phenotypic diagnosis of dwarfism in six Friesian horses.


    Back, W; van der Lugt, J J; Nikkels, P G J; van den Belt, A J M; van der Kolk, J H; Stout, T A E


    An extreme form of abnormal development, dwarfism, is common in man and some animals, but has not been officially reported in horses. Within the Friesian horse breed, congenital dwarfism has been recognised for many years, but no detailed report exists on its phenotype. The most salient feature of the dwarf syndrome is the physeal growth retardation in both limbs and ribs. Affected animals have approximately 25% shorter fore- and hindlimbs and approximately 50% reduced bodyweight. Postnatal growth is still possible in these animals, albeit at a slower rate: the head and back grow faster than the limbs and ribs leading to the characteristic disproportional growth disturbance. Thus, adult dwarfs exhibit a normal, but a relatively larger head conformation, a broader chest with narrowing at the costochondral junction, a disproportionally long back, abnormally short limbs, hyperextension of the fetlocks and narrow long-toed hooves. Furthermore, a dysplastic metaphysis of the distal metacarpus and metatarsus is radiographically evident. Microscopic analysis of the growth plates at the costochondral junction shows an irregular transition from cartilage to bone, and thickening and disturbed formation of chondrocyte columns, which is similar to findings in osteochondrodysplasia.

  4. In vitro and in vivo study of additive manufactured porous Ti6Al4V scaffolds for repairing bone defects

    PubMed Central

    Li, Guoyuan; Wang, Lei; Pan, Wei; Yang, Fei; Jiang, Wenbo; Wu, Xianbo; Kong, Xiangdong; Dai, Kerong; Hao, Yongqiang


    Metallic implants with a low effective modulus can provide early load-bearing and reduce stress shielding, which is favorable for increasing in vivo life-span. In this research, porous Ti6Al4V scaffolds with three pore sizes (300~400, 400~500, and 500~700 μm) were manufactured by Electron Beam Melting, with an elastic modulus range of 3.7 to 1.7 GPa. Cytocompatibility in vitro and osseointegration ability in vivo of scaffolds were assessed. hBMSCs numbers increased on all porous scaffolds over time. The group with intended pore sizes of 300 to 400 μm was significantly higher than that of the other two porous scaffolds at days 5 and 7. This group also had higher ALP activity at day 7 in osteogenic differentiation experiment. The scaffold with pore size of 300 to 400 μm was implanted into a 30-mm segmental defect of goat metatarsus. In vivo evaluations indicated that the depth of bone ingrowth increased over time and no implant dislocation occurred during the experiment. Based on its better cytocompatibility and favorable bone ingrowth, the present data showed the capability of the additive manufactured porous Ti6Al4V scaffold with an intended pore size of 300 to 400 μm for large segmental bone defects. PMID:27667204

  5. Greater Growth of Proximal Metatarsals in Bird Embryos and the Evolution of Hallux Position in the Grasping Foot.


    Botelho, João Francisco; Smith-Paredes, Daniel; Soto-Acuña, Sergio; Núñez-León, Daniel; Palma, Verónica; Vargas, Alexander O


    In early theropod dinosaurs-the ancestors of birds-the hallux (digit 1) had an elevated position within the foot and had lost the proximal portion of its metatarsal. It no longer articulated with the ankle, but was attached at about mid-length of metatarsal 2 (mt2). In adult birds, the hallux is articulated closer to the distal end of mt2 at ground level with the other digits. However, on chick embryonic day 7, its position is as in early theropods at half-length of mt2. The adult distal location is acquired during embryonic days 8-10. To assess how the adult phenotype is acquired, we produced fate maps of the metatarsals of day 6 chicken embryos injecting the lipophilic tracer DiI. The fates of these marks indicate a larger expansion of the metatarsals at their proximal end, which creates the illusory effect that d1 moves distally. This larger proximal expansion occurs concomitantly with growth and early differentiation of cartilage. Histological analysis of metatarsals shows that the domains of flattened and prehypertrophic chondrocytes are larger toward the proximal end. The results suggest that the distal position of the hallux in the avian foot evolved as a consequence of an embryological period of expansion of the metatarsus toward the proximal end. It also brings attention to the developmental mechanisms leading to differential growth between epiphyses and their evolutionary consequences.

  6. Biomechanics of first ray hypermobility: an investigation on joint force during walking using finite element analysis.


    Wong, Duo Wai-Chi; Zhang, Ming; Yu, Jia; Leung, Aaron Kam-Lun


    Hypermobility of the first ray is suggested to contribute to hallux valgus. The investigation of first ray hypermobility focused on the mobility and range of motion that based on manual examination. The load transfer mechanism of the first ray is important to understand the development and pathomechanism of hallux valgus. In this study, we investigated the immediate effect of the joint hypermobility on the metatarsocuneiform and metatarsophalangeal joint loading through a reduction of the stiffness of the foot ligaments. A three-dimensional foot model was constructed from a female aged 28 via MRI. All foot and ankle bones, including two sesamoids and the encapsulated bulk tissue were modeled as 3D solid parts, linking with ligaments of shell elements and muscles connectors. The stance phase of walking was simulated by the boundary and loading conditions obtained from gait analysis of the same subject. Compared with the normal foot, the hypermobile foot had higher resultant metatarsocuneiform and metatarsophalangeal joint forces. The increases accounted for 18.6% and 3.9% body weight. There was also an abrupt change of metatarsocuneiform joint force in the medial-lateral direction. The predicted results represented possible risk of joint problems and metatarsus primus varus.

  7. Effects of duration of wearing high-heeled shoes on plantar pressure.


    Yin, Chun-Ming; Pan, Xiao-Hua; Sun, Yu-Xin; Chen, Zhi-Bin


    In the present study we investigated the effects of different durations of using high-heeled shoes on plantar pressure and gait. A questionnaire survey and dynamic plantar pressure measurements were performed in 20 control females and 117 females who had worn high-heeled shoes for a long time. According to the duration of using high-heeled shoes (as specified in the questionnaire), subjects were divided into a control group and five groups with different durations of use (i.e. <2years, 2-5years, 6-10years, 11-20years and >20years). Parameters, including peak pressure, impulse and pressure duration, in different plantar regions were measured with the Footscan pressure plate. The 2-5years group had smaller midfoot contact areas for both feet and higher subtalar joint mobility, while the 6-10years group had larger midfoot contact areas for both feet and prolonged foot flat phase during gait. The peak pressure and impulse under the second and fourth metatarsus were increased with the prolonged wearing of high-heeled shoes, and the pressure and impulse under the midfoot were substantially reduced in the 2-5years group. The findings suggest that long-term use of high-heeled shoes can induce changes in arch morphology: the longitudinal arch tends to be elevated within 2-5years; the longitudinal arch tends to be flattened within 6-10years; and the forefoot latitudinal arch tends to collapse in more than 20years.

  8. In vitro and in vivo study of additive manufactured porous Ti6Al4V scaffolds for repairing bone defects

    NASA Astrophysics Data System (ADS)

    Li, Guoyuan; Wang, Lei; Pan, Wei; Yang, Fei; Jiang, Wenbo; Wu, Xianbo; Kong, Xiangdong; Dai, Kerong; Hao, Yongqiang


    Metallic implants with a low effective modulus can provide early load-bearing and reduce stress shielding, which is favorable for increasing in vivo life-span. In this research, porous Ti6Al4V scaffolds with three pore sizes (300~400, 400~500, and 500~700 μm) were manufactured by Electron Beam Melting, with an elastic modulus range of 3.7 to 1.7 GPa. Cytocompatibility in vitro and osseointegration ability in vivo of scaffolds were assessed. hBMSCs numbers increased on all porous scaffolds over time. The group with intended pore sizes of 300 to 400 μm was significantly higher than that of the other two porous scaffolds at days 5 and 7. This group also had higher ALP activity at day 7 in osteogenic differentiation experiment. The scaffold with pore size of 300 to 400 μm was implanted into a 30-mm segmental defect of goat metatarsus. In vivo evaluations indicated that the depth of bone ingrowth increased over time and no implant dislocation occurred during the experiment. Based on its better cytocompatibility and favorable bone ingrowth, the present data showed the capability of the additive manufactured porous Ti6Al4V scaffold with an intended pore size of 300 to 400 μm for large segmental bone defects.

  9. Lower extremity abnormalities in children.


    Sass, Pamela; Hassan, Ghinwa


    Rotational and angular problems are two types of lower extremity abnormalities common in children. Rotational problems include intoeing and out-toeing. Intoeing is caused by one of three types of deformity: metatarsus adductus, internal tibial torsion, and increased femoral anteversion. Out-toeing is less common than intoeing, and its causes are similar but opposite to those of intoeing. These include femoral retroversion and external tibial torsion. Angular problems include bowlegs and knock-knees. An accurate diagnosis can be made with careful history and physical examination, which includes torsional profile (a four-component composite of measurements of the lower extremities). Charts of normal values and values with two standard deviations for each component of the torsional profile are available. In most cases, the abnormality improves with time. A careful physical examination, explanation of the natural history, and serial measurements are usually reassuring to the parents. Treatment is usually conservative. Special shoes, cast, or braces are rarely beneficial and have no proven efficacy. Surgery is reserved for older children with deformity from three to four standard deviations from the normal.

  10. [Malian first observation of disseminated African histoplasmosis with predominant bone localizations in an HIV-negative child in Bamako (Mali). Review of the literature].


    Minta, D K; Sylla, M; Traoré, A M; Soukho-Kaya, A; Coulibaly, I; Diallo, K; Théra, M A; Sidibé, A T; Sidibé, S; Traoré, H A; Pichard, E; Chabasse, D


    Endemic deep fungal infections are still under recognised diseases in daily medical practice because of their rarity in sub-Saharan area. The African histoplasmosis Histoplasma capsulatum var. duboisii (H. capsulatum duboisii) is the most frequent variety described in Mali through limited studies in adult patients, since the first case described by Catanei and Kervran (1945). Our case report is a disseminated histoplasmosis in a young 6-year-old african child. He was male and rural. The infectious localisations were mucosae, skin, lymphnodes, urinary tract and bones. Evolution has been marred by an episode of worsening of symptoms despite initial clinical improvement with ketoconazole. After healing of mucocutaneous lesions, we noticed a limitation of ampliation of both wrists. The radiographic bone lesions were lysis of the right lower end of the right radius and cubitus and fragmentation of cubital epiphysis of the same arm. Lacunes were present on the fifth right finger in metatarsus and phalanx; lacune and blowing aspect of the second phalanx of the left third finger was noted. The disseminated form of African histoplasmosis may occur in HIV-negative subject. The prognosis depends on early diagnosis and administration of appropriate and well-conducted therapy.

  11. Development of congenital clubfoot during growth: a long-term study on the basis of pedobarography, biomechanics, and magnetic resonance imaging measurements of muscle volumes.


    Lampe, Renée; Mitternacht, Jürgen; von Pfister, Lorenz; Turova, Varvara; Blumenstein, Tobias; Alves-Pinto, Ana


    The aim of this study was to clarify the degree to which the operated congenital asymptomatic clubfoot still shows malpositions or whether it approaches a physiological development with increasing age. Clubfeet of 12 children were examined repeatedly over up to 10 years using pedobarography. The muscle volumes of the lower legs were investigated with MRI and compared with those of a healthy control group. Although some characteristics of clubfoot remained in the plantar pressure distribution, a gradual decrease in the heel and metatarsus load accompanied by an increase in the forefoot load could be registered as is typical for a developing healthy child's foot. The MRI showed a reduced volume of all muscles of the affected lower leg. A correlation was detected between the measured moments in the upper and lower ankle joints and the volumes of the muscles that move these joints. Even though a functional and anatomical separation between the two groups existed, the general developmental changes during growth were similar. The combination of pedobarographic data and derived joint moments with MRI-measured muscle volumes indicated that higher ankle joint moments in clubfoot were associated with smaller muscle volume and were therefore generated by higher joint rigidity.

  12. Revised generic placement of Brachypelma embrithes (Chamberlin & Ivie, 1936) and Brachypelma angustum Valerio, 1980, with definition of the taxonomic features for identification of female Sericopelma Ausserer, 1875 (Araneae, Theraphosidae)

    PubMed Central

    Gabriel, Ray; Longhorn, Stuart J.


    Abstract The tarantula genus Sericopelma was originally defined based on male specimens, most notably lacking tibial spurs on leg I. Early female specimens were unrecognised as Sericopelma, and typically placed in Eurypelma – a dumping ground for problem specimens. The first females were only later recognised, but authors failed to adequately define female Sericopelma. Here, the holotypes of the southern-most alleged Brachypelma species, Brachypelma embrithes (Chamberlin & Ivie, 1936) and Brachypelma angustum Valerio, 1980 were examined, and finding both to possess defining characteristics of Sericopelma were transferred. The taxonomic attributes to define Sericopelma relative to Brachypelma and select other Neotropical genera are discussed, especially for females. As important diagnostic characters for Sericopelma, the single (unilobar) spermathecae swollen at the apex forming a P-shaped cross-section, metatarsus IV with trace scopula, femur IV with a dense retrolateral pad of plumose hair, plus other attributes. Some past confusion in these characters are clarified and Sericopelma relative to Brachypelma and Megaphobema mesomelas are discussed. Finally recommendations are given about these taxonomic changes for CITES regulations. PMID:26487826

  13. Morphological adaptation of the calamistrum to the cribellate spinning process in Deinopoidae (Uloboridae, Deinopidae)

    PubMed Central

    Joel, Anna-Christin; Scholz, Ingo; Orth, Linda; Kappel, Peter; Baumgartner, Werner


    Spiders are famous for their silk with fascinating mechanical properties. However, some can further produce, process and handle nano fibres, which are used as capture threads. These ‘cribellate spiders’ bear a specialized setae comb on their metatarsus (calamistrum), which modifies cribellate nano fibres to assemble a puffy structure within the capture thread. Among different species, the calamistrum morphology can differ remarkably. Although a model of thread production has been established for Uloborus plumipes, it is not resolved if/how different shaped calamistra influence the production process. We were able to transfer the model without restrictions to spiders with different shaped calamistra. Fibres are not locked between setae but are passing across a rather smooth surface-like area on the calamistrum. This area can be relocated, explaining the first morphological difference between calamistra, without changing the influence of the calamistrum on fibres. By performing an elongated leg movement, contact between fibres and calamistrum could be adjusted after finishing thread production. This movement has to bring the thread in contact with the second morphological peculiarity: cribellate teeth. We suggest these teeth are used to handle the thread independently of the spinnerets, a feature only necessary for spiders, which do not move during web construction. PMID:26998332

  14. Orthopaedic conditions in the newborn.


    Sankar, Wudbhav N; Weiss, Jennifer; Skaggs, David L


    The occasional consultation on a neonate can be unfamiliar territory for many orthopaedic surgeons. Just as children are not little adults, newborns are not just little children; rather, they have a unique physiology that affects the presentation of their orthopaedic concerns. Careful physical examination with appropriate understanding of neonatal development is essential to making the proper diagnosis. A flail extremity in the newborn is most commonly attributed to fracture or brachial plexus palsy; however, infection must also be considered and ruled out to prevent long-term morbidity. Metatarsus adductus is the most common foot abnormality, but clubfoot, calcaneovalgus deformity, and congenital vertical talus may also be encountered. Joint contractures that spontaneously improve are normal in the newborn, but it is important to identify and institute proper treatment for early developmental dysplasia of the hip, congenital knee dislocation, and torticollis. Clavicular pseudarthrosis and periosteal reactions may be discovered on radiographic examination. A basic understanding of the relevant conditions will help the orthopaedist with the initial diagnosis and management of orthopaedic issues in the newborn.

  15. Intracellular recording from a spider vibration receptor.


    Gingl, Ewald; Burger, Anna-M; Barth, Friedrich G


    The present study introduces a new preparation of a spider vibration receptor that allows intracellular recording of responses to natural mechanical or electrical stimulation of the associated mechanoreceptor cells. The spider vibration receptor is a lyriform slit sense organ made up of 21 cuticular slits located on the distal end of the metatarsus of each walking leg. The organ is stimulated when the tarsus receives substrate vibrations, which it transmits to the organ's cuticular structures, reducing the displacement to about one tenth due to geometrical reasons. Current clamp recording was used to record action potentials generated by electrical or mechanical stimuli. Square pulse stimulation identified two groups of sensory cells, the first being single-spike cells which generated only one or two action potentials and the second being multi-spike cells which produced bursts of action potentials. When the more natural mechanical sinusoidal stimulation was applied, differences in adaptation rate between the two cell types remained. In agreement with prior extracellular recordings, both cell types showed a decrease in the threshold tarsus deflection with increasing stimulus frequency. Off-responses to mechanical stimuli have also been seen in the metatarsal organ for the first time.

  16. Computational characterization of fracture healing under reduced gravity loading conditions.


    Gadomski, Benjamin C; Lerner, Zachary F; Browning, Raymond C; Easley, Jeremiah T; Palmer, Ross H; Puttlitz, Christian M


    The literature is deficient with regard to how the localized mechanical environment of skeletal tissue is altered during reduced gravitational loading and how these alterations affect fracture healing. Thus, a finite element model of the ovine hindlimb was created to characterize the local mechanical environment responsible for the inhibited fracture healing observed under experimental simulated hypogravity conditions. Following convergence and verification studies, hydrostatic pressure and strain within a diaphyseal fracture of the metatarsus were evaluated for models under both 1 and 0.25 g loading environments and compared to results of a related in vivo study. Results of the study suggest that reductions in hydrostatic pressure and strain of the healing fracture for animals exposed to reduced gravitational loading conditions contributed to an inhibited healing process, with animals exposed to the simulated hypogravity environment subsequently initiating an intramembranous bone formation process rather than the typical endochondral ossification healing process experienced by animals healing in a 1 g gravitational environment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1206-1215, 2016.

  17. Ultrasound evaluation of foot deformities in infants.


    Miron, Marie-Claude; Grimard, Guy


    Foot deformity in infants is the most common congenital musculoskeletal condition. A precise diagnosis can sometimes be impossible to establish clinically. Radiologic imaging plays a major role in the evaluation of musculoskeletal abnormalities. However conventional imaging techniques, such as plain radiographs of the foot, are of very little help in this age group because of the lack of ossification of the tarsal bones. US presents a significant advantage because it permits the visualization of cartilaginous structures. This leads to the detailed assessment of foot deformities in infants. Furthermore, US can also be used as a dynamic imaging modality. Different scanning views are beneficial to evaluate the complete anatomy of the foot; depending on the suspected clinical diagnosis, some planes are more informative to display the pathological features of a specific deformity. We describe the US findings of five of the most common foot deformities referred to our pediatric orthopedic clinic (clubfoot, simple metatarsus adductus, skewfoot, and oblique and vertical talus). For each deformity we propose a specific imaging protocol based on US to provide an accurate diagnosis. US is a complementary tool to the clinical examination for determining the diagnosis and the severity of the deformity and also for monitoring the efficacy of treatment. Radiologists investigating foot deformities in infants should consider using US for the detailed assessment of the foot in this age group.

  18. Influence of high-altitude grazing on bone metabolism of growing sheep.


    Liesegang, A; Hüttenmoser, D; Risteli, J; Leiber, F; Kreuzer, M; Wanner, M


    The objective of this study was to identify the effect of high alpine grazing, associated with varying pasture grass qualities and more pronounced exercise on typically steep slopes, on bone metabolism by improving bone density and enhancing bone turnover in growing sheep. Twenty-four 5-month-old sheep were randomly assigned to two groups. One group was kept at high altitude (HA; 2000-2200 m a.s.l.) for 3 months, and the other group (C; control) remained in the lowlands (400 m a.s.l.). Both groups were kept in grazing pastures with access to good-quality swards. Before the start of the experiment, blood samples were taken, the sheep were weighed, and the left metatarsus of each animal was analysed by quantitative computer tomography. After 1 month, blood samples were taken and body weight was measured, followed by biweekly sampling. Finally, the animals were slaughtered, and the bones were collected for analysis of various bone parameters. Body weight development did not differ between the groups. Concentrations of 25-OH-Vitamin D, carboxy-terminal telopeptide of type I collagen and activities of bone-specific alkaline phosphatase were always higher in the HA group than in the C group, except on the last two sampling dates. Bone mineral content and density increased in both groups during the experiment, but more intensively in the HA group. In addition, the cortical thickness of the HA group increased. The present study demonstrates an increase in bone turnover and mineral content of the bones of the growing sheep grazing in high alpine pastures. The factors associated with HA grazing, therefore, clearly seem to improve bone composition.

  19. New Bio-Ceramization Processes Applied to Vegetable Hierarchical Structures for Bone Regeneration: An Experimental Model in Sheep

    PubMed Central

    Filardo, Giuseppe; Tampieri, Anna; Cabezas-Rodríguez, Rafael; Di Martino, Alessandro; Fini, Milena; Giavaresi, Gianluca; Lelli, Marco; Martínez-Fernández, Julian; Martini, Lucia; Ramírez-Rico, Joaquin; Salamanna, Francesca; Sandri, Monica; Sprio, Simone; Marcacci, Maurilio


    Bone loss is still a major problem in orthopedics. The purpose of this experimental study is to evaluate the safety and regenerative potential of a new scaffold based on a bio-ceramization process for bone regeneration in long diaphyseal defects in a sheep model. The scaffold was obtained by transformation of wood pieces into porous biomorphic silicon carbide (BioSiC®). The process enabled the maintenance of the original wood microstructure, thus exhibiting hierarchically organized porosity and high mechanical strength. To improve cell adhesion and osseointegration, the external surface of the hollow cylinder was made more bioactive by electrodeposition of a uniform layer of collagen fibers that were mineralized with biomimetic hydroxyapatite, whereas the internal part was filled with a bio-hybrid HA/collagen composite. The final scaffold was then implanted in the metatarsus of 15 crossbred (Merinos-Sarda) adult sheep, divided into 3 groups: scaffold alone, scaffold with platelet-rich plasma (PRP) augmentation, and scaffold with bone marrow stromal cells (BMSCs) added during implantation. Radiological analysis was performed at 4, 8, 12 weeks, and 4 months, when animals were sacrificed for the final radiological, histological, and histomorphometric evaluation. In all tested treatments, these analyses highlighted the presence of newly formed bone at the bone scaffolds' interface. Although a lack of substantial effect of PRP was demonstrated, the scaffold+BMSC augmentation showed the highest value of bone-to-implant contact and new bone growth inside the scaffold. The findings of this study suggest the potential of bio-ceramization processes applied to vegetable hierarchical structures for the production of wood-derived bone scaffolds, and document a suitable augmentation procedure in enhancing bone regeneration, particularly when combined with BMSCs. PMID:24099033



    Dyson, Sue; Blunden, Anthony; Murray, Rachel


    Injuries of the plantar soft tissues of the tarsus and proximal metatarsus can be a source of lameness in horses, however published information is lacking on high field MRI characteristics of these tissues. Objectives of the current anatomic study were to (1) describe high-field MRI features of the plantar tarsal and proximal metatarsal soft tissues; and (2) compare MRI findings with gross and histological appearances of selected structures for a sample of cadaver limbs from non-lame horses. Single hindlimbs for 42 horses, and right and left hindlimbs for eight horses were scanned using high-field MRI. The MRI findings were described for the 50 single limbs; and the MRI, gross postmortem and histological findings were compared for the eight pairs of hindlimbs. The superficial digital flexor tendon had uniform low signal intensity, surrounded by the flexor retinaculum of intermediate to high signal intensity on all sequences. The lateral digital flexor tendon had slightly higher signal intensity, enclosed on the plantaromedial aspects by the low signal intensity metatarsocalcaneal ligament. The accessory ligament of the deep digital flexor tendon varied in size and signal intensity. The proximal and distal plantar ligaments, accessory ligament of the suspensory ligament, and calcaneoquartal ligament had low signal intensity. The long plantar ligament comprised a number of related parts, separated by lines of high signal intensity corresponding with fibrous septae seen in gross anatomical specimens. The plantar aspect of the ligament had uniform low signal intensity in all sequences, but the dorsal half was more heterogeneous with multifocal spots or lines of higher signal intensity.

  1. Influence of UVB exposure on the vitamin D status and calcium homoeostasis of growing sheep and goats.


    Kovács, S; Wilkens, M R; Liesegang, A


    The purpose of this study was to investigate the influence of exposure to ultraviolet radiation (UVB) on vitamin D status, intestinal calcium absorption and bone metabolism in growing sheep and goats. The hypothesis was that growing sheep and goats are able to synthesise vitamin D within their skin as a result of UVB exposure and that respective consequences for their vitamin D blood levels and the associated parameters can be shown. Fourteen 18-week-old lambs and goat kids were kept in an UVB-free environment and randomly assigned to two groups. One group was daily exposed to UVB (300 watt) for 12 weeks, and the other served as a control group. Except for the exposure to UVB, all animals were kept under the same conditions and fed according to their requirements. Before the start of the experiment and every second week, blood samples were taken. Also the left metatarsus of each animal was analysed by quantitative computer tomography to test for bone mineral status before the start, in week 7 and at the end of the experiment. After 12 weeks, the animals were slaughtered and samples were taken from skin, gastrointestinal tract and kidney for further analyses. In this study, exposure to UVB led to increased serum 1,25-dihydroxyvitamin D (1,25VitD) levels in goat kids, whereas in lambs, serum 25-hydroxyvitamin D (25VitD) levels were increased. In both species UVB-exposed animals showed lower 7-dehydrocholesterol (7DHC) values in skin than their respective control groups. These results indicate that growing goat kids and lambs are able to synthesise vitamin D in the skin when being exposed to UVB.

  2. Observed changes in radiographic measurements of the first ray after frontal and transverse plane rotation of the hallux: does the hallux drive the metatarsal in a bunion deformity?


    Dayton, Paul; Feilmeier, Mindi; Kauwe, Merrell; Holmes, Colby; McArdle, Austin; Coleman, Nathan


    It is well known that the pathologic positions of the hallux and the first metatarsal in a bunion deformity are multiplanar. It is not universally understood whether the pathologic changes in the hallux or first metatarsal drive the deformity. We have observed that frontal plane rotation of the hallux can result in concurrent positional changes proximally in the first metatarsal in hallux abducto valgus. In the present study, we observed the changes in common radiographic measurements used to evaluate a bunion deformity in 5 fresh frozen cadaveric limbs. We measured the tibial sesamoid position, 1-2 intermetatarsal angle, and first metatarsal cuneiform angle on anteroposterior radiographs after frontal and transverse plane manipulation of the hallux. When the hallux was moved into an abducted and valgus position, a statistically significant increase was found in the tibial sesamoid position (p = .016). However, we did not observe a significant increase in the intermetatarsal angle (p = .070) or medial cuneiform angle (p = .309). When the hallux was manipulated into an adducted and varus position, a statistically significant decrease in the intermetatarsal angle (p = .02) and a decrease in the tibial sesamoid position (p = .016) was seen, with no significant change in the medial cuneiform angle (p = .360). We also observed a consistent rounding of the lateral aspect of the first metatarsal head and an increase in the concavity of the lateral metatarsal shaft, with valgus rotation of the hallux. From these observations, it is possible that the hallux could drive the proximal changes in the first ray that lead to metatarsus primus adducto valgus deformity.

  3. Bunion correction using proximal chevron osteotomy: a single-incision technique.


    Sammarco, G J; Russo-Alesi, F G


    Proximal chevron first metatarsal osteotomy with lateral capsulotomy, adductor tenotomy, and binding of the first and second metatarsals was reviewed in 88 consecutive cases. Seventy-two cases in 55 patients are reported, with an average clinical follow-up of 41 months. The hallux valgus angle improved an average of 15 degrees , from 32.0 degrees preoperatively to an average of 17.0 degrees postoperatively. The intermetatarsal I-II angle improved an average of 5.5 degrees, from 15.3 degrees preoperatively to 9.0 degrees postoperatively. The lateral plantar first metatarsal angle did not change. First metatarsal length was decreased by 2.0 mm. Union occurred at an average of 2 months. Sesamoid position improved 49%, from a preoperative average subluxation of 80% to a postoperative average subluxation of 29%. Subjective foot score profiles improved from a preoperative average of 70.1/100 to a postoperative average of 94.4/100 with respect to pain, deformity, motion, disability, and cosmesis. There were 10 patients with complications, including three patients with delayed unions, two with second metatarsal stress fractures, one with hallux varus, two with hallux limitus, one with progressive arthritis, one with cellulitis, and one with hallux elevatus. Eighty-four percent of the patients stated that they would undergo the procedure again without reservation, 9% would proceed with reservation, and 7% would not proceed with surgery again if offered. This technique provides reliable successful long-term results for the treatment of moderate and severe symptomatic bunion, hallux valgus, and metatarsus primus varus.

  4. Vascular anatomy of the metatarsal bones and the interosseous muscles of the foot.


    Alagoz, Murat Sahin; Orbay, Hakan; Uysal, Ahmet Cagri; Comert, Ayhan; Tuccar, Eray


    Utilization of the metatarsal bones and interosseous muscles in foot reconstruction should be based on the vascular anatomy of the metatarsal bones and interosseous muscles. We studied the vascular anatomy of the metatarsal bones and the interosseous muscles to design a split metacarpal musculoosseous flap and dorsal interosseous muscle flap. Twenty-two feet from eleven cadavers that had been embalmed in formalin were studied. Dissection was done using a dissection microscope (x3.5), delineating meticulously the arcuate artery, dorsal metatarsal arteries and the small branches arising from the metatarsal arteries. The dorsal metatarsal arteries do not course at the midline of the interosseous muscles. The first dorsal metatarsal artery proceeds close to the first metatarsal bone in the first metatarsal space. While proceeding to the distal, it shoots out a branch that individually feeds the lateral head of the first dorsal metatarsal muscle and medial face of the second metatarsus, thereby feeding muscle and bone. Except for this branch, the first dorsal metatarsal gives off segmental and periosteal branches that individually feed the medial heads of the first dorsal metatarsal muscle and first metatarsal bone. The second, third and fourth metatarsal arteries proceed close to the third, fourth and fifth metatarsal bones in the metatarsal spaces. In these courses, the arteries give out segmental branches to both faces of the interosseous muscles and periosteal branches to the medial face of metatarsal bones. For defects or disease of the ankle bones, the metatarsal bones can be split at the medial border distally, and a split metatarsal musculoosseous flap, based proximally on the dorsal metatarsal artery, can be done. Distal intermetatarsal anastomoses between the dorsal and plantar vascular networks enables a split metatarsal musculoosseous flap based distally, including the dorsal metatarsal artery for bony defects of the proximal phalanx.

  5. Descriptions of the lower limb skeleton of Homo floresiensis.


    Jungers, W L; Larson, S G; Harcourt-Smith, W; Morwood, M J; Sutikna, T; Due Awe, Rokhus; Djubiantono, T


    Bones of the lower extremity have been recovered for up to nine different individuals of Homo floresiensis - LB1, LB4, LB6, LB8, LB9, LB10, LB11, LB13, and LB14. LB1 is represented by a bony pelvis (damaged but now repaired), femora, tibiae, fibulae, patellae, and numerous foot bones. LB4/2 is an immature right tibia lacking epiphyses. LB6 includes a fragmentary metatarsal and two pedal phalanges. LB8 is a nearly complete right tibia (shorter than that of LB1). LB9 is a fragment of a hominin femoral diaphysis. LB10 is a proximal hallucal phalanx. LB11 includes pelvic fragments and a fragmentary metatarsal. LB13 is a patellar fragment, and LB14 is a fragment of an acetabulum. All skeletal remains recovered from Liang Bua were extremely fragile, and some were badly damaged when they were removed temporarily from Jakarta. At present, virtually all fossil materials have been returned, stabilized, and hardened. These skeletal remains are described and illustrated photographically. The lower limb skeleton exhibits a uniquely mosaic pattern, with many primitive-like morphologies; we have been unable to find this combination of ancient and derived (more human-like) features in either healthy or pathological modern humans, regardless of body size. Bilateral asymmetries are slight in the postcranium, and muscle markings are clearly delineated on all bones. The long bones are robust, and the thickness of their cortices is well within the ranges seen in healthy modern humans. LB1 is most probably a female based on the shape of her greater sciatic notch, and the marked degree of lateral iliac flaring recalls that seen in australopithecines such as "Lucy" (AL 288-1). The metatarsus has a human-like robusticity formula, but the proximal pedal phalanges are relatively long and robust (and slightly curved). The hallux is fully adducted, but we suspect that a medial longitudinal arch was absent.

  6. Partial gravity unloading inhibits bone healing responses in a large animal model.


    Gadomski, Benjamin C; McGilvray, Kirk C; Easley, Jeremiah T; Palmer, Ross H; Santoni, Brandon G; Puttlitz, Christian M


    The reduction in mechanical loading associated with space travel results in dramatic decreases in the bone mineral density (BMD) and mechanical strength of skeletal tissue resulting in increased fracture risk during spaceflight missions. Previous rodent studies have highlighted distinct bone healing differences in animals in gravitational environments versus those during spaceflight. While these data have demonstrated that microgravity has deleterious effects on fracture healing, the direct translation of these results to human skeletal repair remains problematic due to substantial differences between rodent and human bone. Thus, the objective of this study was to investigate the effects of partial gravitational unloading on long-bone fracture healing in a previously-developed large animal Haversian bone model. In vivo measurements demonstrated significantly higher orthopedic plate strains (i.e. load burden) in the Partial Unloading (PU) Group as compared to the Full Loading (FL) Group following the 28-day healing period due to inhibited healing in the reduced loading environment. DEXA BMD in the metatarsus of the PU Group decreased 17.6% (p<0.01) at the time of the ostectomy surgery. Four-point bending stiffness of the PU Group was 4.4 times lower than that of the FL Group (p<0.01), while µCT and histomorphometry demonstrated reduced periosteal callus area (p<0.05), mineralizing surface (p<0.05), mineral apposition rate (p<0.001), bone formation rate (p<0.001), and periosteal/endosteal osteoblast numbers (p<0.001/p<0.01, respectively) as well as increased periosteal osteoclast number (p<0.05). These data provide strong evidence that the mechanical environment dramatically affects the fracture healing cascade, and likely has a negative impact on Haversian system healing during spaceflight.

  7. Handheld mechanical nociceptive threshold testing in dairy cows – intra-individual variation, inter-observer agreement and variation over time

    PubMed Central

    Raundal, Peter M; Andersen, Pia H; Toft, Nils; Forkman, Björn; Munksgaard, Lene; Herskin, Mette S


    Objective To examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed. Study design Prospective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time. Animals One hundred and fifteen healthy, loose-housed Danish Holstein cattle. Methods We evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0–10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0–1000 gf). Each cow received 5–6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant. Results The CVs did not differ [range 0.34–0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01). Conclusion and clinical relevance All methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia. PMID:24734991

  8. A laser-based method to measure thermal nociception in dairy cows: short-term repeatability and effects of power output and skin condition.


    Herskin, M S; Müller, R; Schrader, L; Ladewig, J


    To validate a laser-based method to measure thermal nociception in dairy cows (e.g., for the use in studies on stress-induced analgesia), we performed three experiments to observe the behavioral responses to a computer-controlled CO2 laser beam applied to the skin on the caudal aspect of the metatarsus. In Exp. 1, effects of power output (0, 1.3, 1.8, 2.2, 2.4 and 2.6 W) on nociceptive responses were examined using 18 dairy cows kept and tested in tie stalls. Increasing the power output affected the latencies to respond (decreasing latencies, P < or = 0.01), types of response (less nonresponding and more kicking, P < 0.0001), and behavior during (increasing frequency of tail flicking, P = 0.003) and between single laser exposures (increasing frequency of kicking, P = 0.02). Therefore, behavioral responses to a laser stimulus seem to be a valid measure of nociception in dairy cows. Repeatability within 15 min was investigated in Exp. 2 using n = 36 dairy cows kept and tested in tie stalls and a power output of 1.8 W. The variables' latency to move the exposed leg and frequency of tail flicking during laser exposure showed the highest level of repeatability (0.50 and 0.38, respectively). However, retesting at t = 15 min led to increased responses in terms of shorter latencies to respond (P < 0.05), increased kicking (P = 0.05), and tail flicking (P = 0.02), which probably can be explained by sensitization. Effects of power output (1.0 vs. 1.8 W) and skin condition (naked vs. intact) were examined in Exp. 3 on 11 group-housed dairy cows, tested just outside their home pen. Increasing the power output and shaving off hair led to increased responses as seen by shorter latencies to respond (P < 0.0001), less nonresponding (P < 0.0001), and increased kicking (P = 0.0003), as well as reduced intra- and interindividual variability (P < or = 0.04). In conclusion, the results of these experiments suggest that behavioral responses to laser stimulation are a valid and reliable

  9. Interstitial deletion of chromosome 2q32-34 associated with multiple congenital anomalies and a urea cycle defect (CPS I deficiency).


    Loscalzo, M L; Galczynski, R L; Hamosh, A; Summar, M; Chinsky, J M; Thomas, G H


    A de novo deletion of the long arm of chromosome 2 at 2q31-33 was observed in the fetal amniocyte G-banded karyotype performed because of possible multiple malformations identified by ultrasound at 23 weeks gestation. Two days after the uneventful term delivery of a 2.45 kg male, the neonate experienced cardiopulmonary decompensation and biochemical changes compatible with carbamoyl phosphate synthetase I (CPS I) deficiency (elevated ammonia with a peak of 948 micromol/L, deficiency of citrulline, and no increase in orotic acid). The child died on day 3 of life. Physical anomalies confirmed at autopsy included double superior vena cava, ectopic adrenal tissue, and metatarsus adductus. The autopsy also revealed histologic evidence consistent with CPS deficiency, most notably microvesicular steatosis of the liver and Alzheimer's Type II changes with hypertrophic astrocytes in the basal ganglia. A postnatal lymphocyte karyotype confirmed the chromosome 2q31-33 deletion. Enzyme analysis on postmortem liver tissue confirmed the diagnosis of CPS deficiency. CPS I is reported to be mapped to 2q35 by NCBI ( and 2q34 by ENSEMBL ( The UCSC Human Genome Browser July 2003 assembly also places the gene at 2q34 ( Fluorescence in situ hybridization (FISH) analysis with a BAC clone (RP11-349G4) of CPS I demonstrated that one copy of the gene was deleted in this infant. Using additional probes corresponding to the bands in the region of deletion, we identified the deleted region as 2q32-2q34. Our observations support the CPS I map position (ENSEMBL, UCSC) at 2q34. Additionally, potential conditions associated with deletions narrowly defined by standard cytogenetic techniques merit consideration in prenatal counseling. As demonstrated here, deletions may not only result in malformations and mental retardation but also increase the likelihood of revealing mutated genes located in the undeleted

  10. Functional anatomy and imaging of the foot.


    Ridola, C; Palma, A


    The foot is constituted from a series of small bones making a segmented structure with multiple joints, likened to a dome, in contact with the ground in three points: posteriorly the calcanear tuberosity; anteriorly and medially the head of 1st metatarsum, and anteriorly and laterally the head of 5th metatarsum. In fact, each foot presents a semi-arch whose base is represented by the lateral border and the summit by the medial border of the foot. The foot has been likened to a half-dome, so that when the medial borders of the two feet are placed together, a complete dome is formed. In the foot are present two longitudinal arches: the medial consists of the calcaneus, the talus, the navicular, the three cuneiform bones and the first three metatarsal bones. It is more arcuated and elastic then the lateral, that consist of the calcaneus, the cuboid and the 4th and 5th metatarsus. This is flattened and in contact with the ground. We can identify two transverse arches between longitudinal arches, extending from the medial to the lateral borders of the foot: the first is a lancet dome, between midfoot and forefoot, at the tarsometatarsal joint level; it consists of the bases of the metatarsal bones and the cuboid and the three cuneiform bones; the second is at flat dome, in correspondence of forefoot, at the metatarsophalangeal joint level; it consists of the bases of the proximal phalanges of the fingers and the head of five metatarsal bones. Longitudinal and transversal arches are supported from: the shape of stones of the structure (foot bones); the long and short plantar ligaments, larger and stronger than the dorsal ligaments, tie together the lower edges of the bones; a beam (the plantar aponeurosis and the plantar muscles and tendons) connecting the ends of the bridge effectively prevents separation of the pillars and consequent sagging of the arch; the maintenance of the arch depends on multiple support (ligaments, tendons of extrinsic muscles of the foot

  11. An in vivo ovine model of bone tissue alterations in simulated microgravity conditions.


    Gadomski, Benjamin C; McGilvray, Kirk C; Easley, Jeremiah T; Palmer, Ross H; Ehrhart, E J; Haussler, Kevin K; Browning, Raymond C; Santoni, Brandon G; Puttlitz, Christian M


    Microgravity and its inherent reduction in body-weight associated mechanical loading encountered during spaceflight have been shown to produce deleterious effects on important human physiological processes. Rodent hindlimb unloading is the most widely-used ground-based microgravity model. Unfortunately, results from these studies are difficult to translate to the human condition due to major anatomic and physiologic differences between the two species such as bone microarchitecture and healing rates. The use of translatable ovine models to investigate orthopedic-related conditions has become increasingly popular due to similarities in size and skeletal architecture of the two species. Thus, a new translational model of simulated microgravity was developed using common external fixation techniques to shield the metatarsal bone of the ovine hindlimb during normal daily activity over an 8 week period. Bone mineral density, quantified via dual-energy X-ray absorptiometry, decreased 29.0% (p < 0.001) in the treated metatarsi. Post-sacrifice biomechanical evaluation revealed reduced bending modulus (-25.8%, p < 0.05) and failure load (-27.8%, p < 0.001) following the microgravity treatment. Microcomputed tomography and histology revealed reduced bone volume (-35.9%, p < 0.01), trabecular thickness (-30.9%, p < 0.01), trabecular number (-22.5%, p < 0.05), bone formation rate (-57.7%, p < 0.01), and osteoblast number (-52.5%, p < 0.001), as well as increased osteoclast number (269.1%, p < 0.001) in the treated metatarsi of the microgravity group. No significant alterations occurred for any outcome parameter in the Sham Surgery Group. These data indicate that the external fixation technique utilized in this model was able to effectively unload the metatarsus and induce significant radiographic, biomechanical, and histomorphometric alterations that are known to be induced by spaceflight. Further, these findings demonstrate that the