Longer Tibiae Research Articles

One less monotypic genus: a new species of the enigmatic Magnopholcomma (Araneae, Theridiidae) from Tasmania (Australia) with comments on its genital morphology and the generic placement in Pholcommatinae

A second species in the spider genus Magnopholcomma Wunderlich, 2008 (family Theridiidae Sundevall, 1833) is described based on a male found at Fortescue Bay in Tasman National Park (Tasmania, Australia). The genus differs from all other genera in the family by somatic characters, specifically the large globular clypeal outgrowth. Magnopholcomma adelphus sp. n. differs from M. globulus Wunderlich, 2008 by somatic and genitalic characters, especially the larger clypeal outgrowth, an inconspicuous fovea, pedipalp with longer tibia, median apophysis strongly basally projected and apical lobe of theridiid tegular apophysis undivided. The genus genital morphology and its systematic position in Pholcommatinae are also discussed, stabilizing the inconsistent nomenclature of sclerites of the male pedipalp (e.g., the interpretation of the theridiid terminal apophysis) of members of the subfamily.

Assessing Leg Length Discrepancy Is Necessary Before Arthroplasty in Patients With Unilateral Crowe Type IV Hip Dislocation.

THA for high-riding developmental dysplasia of the hip (DDH) is challenging in terms of length equalization. Although previous studies suggested preoperative templating on AP pelvic radiographs is insufficient in patients with unilateral high-riding DDH because of hypoplasia of the hemipelvis on the affected side and unequal femoral and tibial length on scanograms, the results were controversial. The EOS™ (EOS™ Imaging) is a biplane X-ray imaging system using slot-scanning technology. Length and alignment measurements have been shown to be accurate. We used the EOS to compare the lower limb length and alignment in patients with unilateral high-riding DDH. (1) Is there an overall leg length difference in patients with unilateral Crowe Type IV hip dysplasia? (2) In patients with unilateral Crowe Type IV hip dysplasia with an overall leg length difference, is there a consistent pattern of abnormalities in the femur or tibia that account for observed differences? (3) What is the impact of unilateral high-riding Crowe Type IV dysplasia on femoral neck offset and knee coronal alignment? Between March 2018 and April 2021, we treated 61 patients with THA for Crowe Type IV DDH (high-riding dislocation). EOS imaging was performed preoperatively in all patients. Eighteen percent (11 of 61) of the patients were excluded because of involvement of the opposite hip, 3% (two of 61) were excluded for neuromuscular involvement, and 13% (eight of 61) had previous surgery or fracture, leaving 40 patients for analysis in this prospective, cross-sectional study. Each patient's demographic, clinical, and radiographic information was collected with a checklist using charts, Picture Archiving and Communication System, and an EOS database. EOS-related measurements that were related to the proximal femur, limb length, and knee-related angles were recorded for both sides by two examiners. The findings of the two sides were statistically compared. The overall limb length was not different between the dislocated and nondislocated sides (mean 725 ± 40 mm versus 722 ± 45 mm, mean difference 3 mm [95% CI -3 to 9 mm); p = 0.08). Apparent leg length was shorter on the dislocated side (mean 742 ± 44 mm versus 767 ± 52 mm, mean difference -25 mm [95% CI -32 to 3 mm]; p < 0.001). We observed that a longer tibia on the dislocated side was the only consistent pattern (mean 338 ± 19 mm versus 335 ± 20 mm, mean difference 4 [95% CI 2 to 6 mm]; p = 0.002), but there was no difference between the femur length (mean 346 ± 21 mm versus 343 ± 19 mm, mean difference 3 mm [95% CI -1 to 7]; p = 0.10). The femur of the dislocated side was longer by greater than 5 mm in 40% (16 of 40) of patients and shorter in 20% (eight of 40). The mean femoral neck offset of the involved side was shorter than that of the normal side (mean 28 ± 8 mm versus 39 ± 8 mm, mean difference -11 mm [95% CI -14 to -8 mm]; p < 0.001). There was a higher valgus alignment of the knee on the dislocated side with a decreased lateral distal femoral angle (mean 84° ± 3° versus 89° ± 3°, mean difference - 5° [95% CI -6° to -4°]; p < 0.001) and increased medial proximal tibia angle (mean 89° ± 3° versus 87° ± 3°, mean difference 1° [95% CI 0° to 2°]; p = 0.04). A consistent pattern of anatomic alteration on the contralateral side does not exist in Crowe Type IV hips except for the length of the tibia. All parameters of the limb length could be shorter, equal to, or longer on the dislocated side. Given this unpredictability, AP pelvis radiographs are not sufficient for preoperative planning, and individualized preoperative planning using full-length images of the lower limbs should be performed before arthroplasty in Crowe Type IV hips. Level I, prognostic study.

Omega-9 Modifies Viscoelasticity and Augments Bone Strength and Architecture in a High-Fat Diet-Fed Murine Model.

The influence of diet on the development of osteoporosis is significant and not fully understood. This study investigated the effect of diets of varying lipid profiles and ω-3, ω-6 and ω-9 composition on the structural and mechanical properties of bone. The hypothesis studied was that a diet high in saturated fat would induce osteoporosis and produce an overall increased detrimental bony response when compared with a diet high in unsaturated ω-6, or ω-9. Male C57BL/6J mice were fed either a control diet, 50:50 mix (saturated:unsaturated) high in ω-9 (HFD50:50), a diet high in saturated fat (HSF) or a polyunsaturated fat diet high in ω-6 (PUFA) over an 8-week duration. Tibiae were retrieved and evaluated using DMA, 3-point-bending, histomorphometry, and microCT. Mice fed a HSF diet displayed key features characteristic of osteoporosis. The loss tangent was significantly increased in the HFD50:50 diet group compared with control (p = 0.016) and PUFA-fed animals (p = 0.049). HFD50:50-fed mice presented with an increased viscous component, longer tibiae, increased loss modulus (p = 0.009), and ultimate stress, smaller microcracks (p < 0.001), and increased trabecular width (p = 0.002) compared with control animals. A diet high in ω-9 resulted in an overall superior bone response and further analysis of its role in bone health is warranted.

Sexual Dimorphism in Bokermannohyla martinsi (Bokermann, 1964) (Anura, Hylidae) with a Report of Male–Male Combat

Abstract. Male-biased sexual size dimorphism (SSD), or a lack of SSD, in amphibians may be related to the territoriality. Male-biased SSD is quite abundant among the species of the Neotropical hylid genus Bokermannohyla. However, direct observations of territorial behaviour such as combat, suggestive of the presence of a male-biased SSD, are rare. We evaluated SSD in B. martinsi and provided a field record of a male–male combat event. We found males to have significantly wider forearm and longer tibia than females. It appears that male forearm hypertrophy is related to territoriality, but we cannot reject the possibility that it is an adaptation to breeding in lotic habitats. Finally, we emphasize the importance of direct natural history observations for understanding patterns of SSD among anurans in particular and amphibians in general.

Stature and body mass estimation from skeletal remains in the European Holocene

Techniques that are currently available for estimating stature and body mass from European skeletal remains are all subject to various limitations. Here, we develop new prediction equations based on large skeletal samples representing much of the continent and temporal periods ranging from the Mesolithic to the 20th century. Anatomical reconstruction of stature is carried out for 501 individuals, and body mass is calculated from estimated stature and biiliac breadth in 1,145 individuals. These data are used to derive stature estimation formulae based on long bone lengths and body mass estimation formulae based on femoral head breadth. Prediction accuracy is superior to that of previously available methods. No systematic geographic or temporal variation in prediction errors is apparent, except in tibial estimation of stature, where northern and southern European formulae are necessary because of the presence of relatively longer tibiae in southern samples. Thus, these equations should bebroadly applicable to European Holocene skeletal samples.

Sexual Size dimorphism in the diving Beetle Laccophilus maculosusSay (coleoptera: Dytiscidae)

Abstract Sexual size dimorphism was quantified for a population of the diving beetle Laccophilus maculosus Say in Northern Ontario, Canada. Consistent with other populations of this species, but in contrast to the general pattern in insects, males were significantly larger than females in terms of body length, elytral length, and pronotal width. There was a significant multivariate difference in body size between the sexes, and discriminant function analysis identified 68.87% of individuals as the correct sex based on measurements of body size. Males also had significantly longer femora, longer tibiae, and larger tarsi on the pro- and mesothoracic legs.

Identity of larval Meristogenys from a single stream in Sabah, Malaysia (Amphibia: Ranidae)

A morphological and molecular survey was conducted to examine the association between larvae and adults of Bornean torrent frog Meristogenys from a stream in Mahua, Crocker Range, Sabah, Malaysia. We identified five discrete morphotypes of larvae, which also showed considerable genetic differentiation. Each larval morphotype was associated through DNA sequence comparisons with adult specimens that had been identified morphologically. One morphotype, identified as M. orphnocnemis, was less similar to the larva of this species than to an unidentified larva, both reported previously. Adults of two other larvae were identified as M. amoropalamus and M. kinabaluensis, but the larval morphotypes differed from previous descriptions of these larvae. Adults associated with another morphotype resembled M. whiteheadi, but had longer tibia. This larval morphotype was dissimilar to previous descriptions of the M. whiteheadi larva, but was similar to another unidentified larva previously reported. No adult specimens were associated with the fifth larval morphotype, which matched the larva reported as M. amoropalamus. From these results, we suspect that either some previous studies include misidentifications or several undescribed, cryptic taxa morphologically resemble known adult species, but differ as larvae.© 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 173-189. © 2007 The Linnean Society of London.

A new giant species of Arthroleptis (Amphibia: Anura) from the Rubeho Mountains, Tanzania

Two giant specimens of Arthroleptis attaining a snout‐vent length of 57 mm, from the Rubeho Mountains in southern Tanzania are described as a new species. They are distinguished from the giant species A. tanneri of the West Usambara Mountains by longer tibiae and larger inner metatarsal tubercles.

Effect of gender on bone turnover in adult rats during simulated weightlessness.

Prologned spaceflight results in bone loss in astronauts, but there is considerable individual variation. The goal of this rat study was to determine whether gender influences bone loss during simulated weightlessness. Six-month-old Fisher 344 rats were hindlimb unweighted for 2 wk, after which the proximal tibiae were evaluated by histomorphometry. There were gender differences in tibia length, bone area, cancellous bone architecture, and bone formation. Compared with female rats, male rats had an 11.6% longer tibiae, a 27.8% greater cortical bone area, and a 37.6% greater trabecular separation. Conversely, female rats had greater cortical (316%) and cancellous (145%) bone formation rates, 28.6% more cancellous bone, and 30% greater trabecular number. Hindlimb unweighting resulted in large reductions in periosteal bone formation and mineral apposition rate in both genders. Unweighting also caused cancellous bone loss in both genders; trabecular number was decreased, and trabecular separation was increased. There was, however, no change in trabecular thickness in either gender. These architectural changes in cancellous bone were associated with decreases in bone formation and steady-state mRNA levels for bone matrix proteins and cancellous bone resorption. In conclusion, there are major gender-related differences in bone mass and turnover; however, the bone loss in hindlimb unweighted adult male and female rats appears to be due to similar mechanisms.

Allometric growth in tyrannosaurids (Dinosauria: Theropoda) from the Upper Cretaceous of North America and Asia

Many tyrannosaurid skeletons have been collected in Canada, the United States, and Mongolia. These fossils tend to represent mature individuals, but juveniles are also known. Skeletons of five genera of tyrannosaurids representing two distinct clades (albertosaurines and tyrannosaurines) were measured, and bivariate analysis was done on 85 dimensions. Allometric differences among mature specimens of different species are shown to be trivial when compared with the allometric differences associated with growth. Nevertheless, albertosaurines tend to be more lightly built than tyrannosaurines. When compared with a tyrannosaurine of the same absolute size, albertosaurines had slightly shorter, lower skulls, shorter ilia, longer tibiae, longer metatarsals, and longer toes. The arms of albertosaurines and tyrannosaurines are the same size, with the exception of Tarbosaurus, which has shorter front limb elements. Tooth counts show individual and interspecific variation, but there is no evidence that tooth numbers are controlled by the size or age of an animal. Dinotyrannus, Jenghizkhan, Maleevosaurus, Shanshanosaurus, Stygivenator, and possibly Nanotyrannus have proportions that suggest they are ontogenetic stages of either Tarbosaurus or Tyrannosaurus.

Chemical and biomechanical characterization of hyperhomocysteinemic bone disease in an animal model.

BackgroundClassical homocystinuria is an autosomal recessive disorder caused by cystathionine β-synthase (CBS) deficiency and characterized by distinctive alterations of bone growth and skeletal development. Skeletal changes include a reduction in bone density, making it a potentially attractive model for the study of idiopathic osteoporosis.MethodsTo investigate this aspect of hyperhomocysteinemia, we supplemented developing chicks (n = 8) with 0.6% dl-homocysteine (hCySH) for the first 8 weeks of life in comparison to controls (n = 10), and studied biochemical, biomechanical and morphologic effects of this nutritional intervention.ResultshCySH-fed animals grew faster and had longer tibiae at the end of the study. Plasma levels of hCySH, methionine, cystathionine, and inorganic sulfate were higher, but calcium, phosphate, and other indices of osteoblast metabolism were not different. Radiographs of the lower limbs showed generalized osteopenia and accelerated epiphyseal ossification with distinct metaphyseal and suprametaphyseal lucencies similar to those found in human homocystinurics. Although biomechanical testing of the tibiae, including maximal load to failure and bone stiffness, indicated stronger bone, strength was proportional to the increased length and cortical thickness in the hCySH-supplemented group. Bone ash weights and IR-spectroscopy of cortical bone showed no difference in mineral content, but there were higher Ca2+/PO43- and lower Ca2+/CO32- molar ratios than in controls. Mineral crystallization was unchanged.ConclusionIn this chick model, hyperhomocysteinemia causes greater radial and longitudinal bone growth, despite normal indices of bone formation. Although there is also evidence for an abnormal matrix and altered bone composition, our finding of normal biomechanical bone strength, once corrected for altered morphometry, suggests that any increase in the risk of long bone fracture in human hyperhomocysteinemic disease is small. We also conclude that the hCySH-supplemented chick is a promising model for study of the connective tissue abnormalities associated with homocystinuria and an important alternative model to the CBS knock-out mouse.

Postcranial skeleton of Eocene Leptictidae (Mammalia), and its implications for behavior and relationships

ABSTRACT The postcranial skeleton of early and middle Eocene leptictids is described based on several specimens from Wyoming and Colorado. Leptictids had a strongly keeled manubrium sterni, relatively short, generalized forelimbs (intermembral index ~60), a moderately robust humerus, stout metacarpals, and ungual phalanges resembling those of fossorial mammals. The femur is slender, with a narrow, elevated patellar trochlea and a posteriorly-directed lesser trochanter. The slightly longer tibia is firmly synostosed with the fibula just distal to midshaft. The fused tibiofibula forms a stable ankle joint with the deep astragalar trochlea. The astragalar neck and the metatarsals are moderately elongate, and there is a pronounced peroneal process on Mt I, probably related to pedal eversion. These traits indicate that leptictids were terrestrial mammals that progressed by quadrupedal walking, running, and hopping (possibly bipedally at high speed), and that burrowed using their forelimbs. Cladistic analysis of postcranial traits groups leptictids with lagomorphs, zalambdalestids, and macroscelidids. Postcranial characters do not support a sister-group relationship between Leptictidae and Lipotyphla.

Allometric Secular Change in the Long Bones from the 1800s to the Present

Allometric secular changes in the six long limb bones for White and Black males from the mid 1800s to the present are examined. Long bone lengths are available from the Terry collection and WWII casualties. We conducted two types of analysis to reveal secular changes. First, allometry scaling coefficients were derived by regressing log bone length onto log stature. These showed that the femur, tibia and fibula were positively allometric with stature, while the humerus, radius and ulna were isometric. The lower limb bones were more positively allometric in the WWII sample than in the Terry sample. Second, secular changes in length of femur and tibia and in the tibia/femur ratio were evaluated, using modern forensic cases in addition to the Terry and WWII samples. This analysis shows that secular increase in lower limb bone length is accompanied by relatively longer tibiae. Secular changes in proportion may render stature formulae based on nineteenth century samples, such as the Terry collection, inappropriate for modern forensic cases. The positive allometry of the lower limb bones argues against using simple femur/stature ratio, which assumes constant proportionality, as an alternative to regression equations.

The Second Collection of, and Variation in, the Rare Neotropical Toad Bufo peripatetes

In 1923, Helen Thompson Gaige collected a single, large (70 mm snout-vent length) male toad (UMMZ 58430) from the Atlantic slopes of upland western Panama (above Boquete, Chiriqui Province on the trail to Almirante, 1500 m). This animal was considered to be Bufo simus by Taylor (1951). Savage (1972) showed that the name B. simus cannot be applied to any North or Central American species, and proposed that the Panama toad represented a distinct species, B. peripatetes. Recently, our attention was directed to a series of toads obviously conspecific with the holotype of B. peripatetes from a second locality, Cerro Bollo, about 80 km ESE of the type locality, on the border between Chiriqui and Bocas del Toro Provinces, about 23 km NNE of San Felix, Chiriqui Province in the area of Escopeta Camp, between 1800-1856 m. These toads were collected during June and July 1980 by R. J. Izor. This sample (USNM 297523-34) includes a series of five adult females (USNM 297525-29), four juveniles (USNM 297523, 297530, 297532, 297534), and three adult males (USNM 297524, 297531, 297533), and permits us to present information on variation, including ontogenetic changes and sexual dimorphism for the species. The toads from Cerro Bollo agree with the holotype (condition in parentheses) except that: (1) the thenar tubercle is wider than the palmar tubercle in five examples, and as wide as the palmar in one (palmar larger than thenar); and (2) the length of the parotoid gland is greater than 75% of the upper eyelid length in seven toads (length of parotoid 75% upper eyelid length). As predicted by Savage (1972), there is marked sexual size dimorphism; females are longer (SVL) than males with proportionally smaller parotoid glands, shorter heads, and longer tibiae (Table 1). The color pattern of males from Cerro Bollo is similar to that of the holotype. The dorsa are uniform tan; the dorsal surfaces of the limbs are tan, with or without vague darker blotches or spots (Fig. 1); the flanks have vague gray marks or distinct dark spots in the groin; the posterior thigh is tan with a few dark spots near the knee, and there is an ocellus-like spot at the knee (light spot completely surrounded by black) in USNM 297531; and the ventral surfaces are tan with a few dark spots on the chest and legs. According to Izor's field notes, the dorsal color of the males is lemon yellow in life. When originally seen two years after preservation, the males were pale yellow and areas now tan or light brown in preservative were of this hue in life. The male holotype (UMMZ 58430) may have been yellow in life but no mention of color is included in the field notes that originally accompanied the specimen. This example has more dark pigment on the groin and thigh areas than the Bollo males, but otherwise does not differ from them