Comparative skeletal anatomy of salt marsh and western harvest mice in relation to locomotor ecology.

The salt marsh harvest mouse (Reithrodontomys raviventris) is an endangered species, endemic to the San Francisco Bay Estuary, that co-occurs with the more broadly distributed species, the western harvest mouse (Reithrodontomys megalotis). Despite their considerable external morphological similarities, the northern subspecies of salt marsh harvest mice have relatively longer and thicker tails than do western harvest mice, which may be related to their abilities to climb emergent marsh vegetation to avoid tidal inundation. We used micro-CT to compare post-cranial skeletal anatomy between the salt marsh and western harvest mouse, to examine whether the salt marsh harvest mouse's restriction to brackish marshes is associated with skeletal adaptations for scansorial locomotion. We found that salt marsh harvest mice exhibited a deeper 3rd caudal vertebra, a more caudally located longest tail vertebra, craniocaudally longer tail vertebrae, and a longer digit III proximal phalanx than western harvest mice. These phalangeal and vertebral characteristics are known to decrease body rotations during climbing, increase contact with substrates, and decrease fall susceptibility in arboreal mammals, suggesting that the salt marsh harvest mouse may be morphologically specialized for scansorial locomotion, adaptive for its dynamic wetland environment.

Phalangeal microgeodic syndrome: a paediatric case series.

We present the clinical and radiological characteristics of phalangeal microgeodic syndrome in a cluster of five children during the second peak of COVID-19 pandemic in the UK. Each child presented with phalangeal swelling and erythema, prompting a comprehensive multi-disciplinary team review to analyse the clinical presentation, blood test results and imaging. The cohort's average age was 14.1 years, ranging from 10.4 to 16.6 years, with two girls and three boys. Four children experienced phalangeal involvement in the hands, whilst one was affected solely in the feet. A rheumatological work-up was performed for all. Hand X-rays performed on three children revealed distinct radiographic features like microgeodes, subperiosteal bone resorption and rarefaction in two cases. However, further MRI showed extensive changes closely correlated with the clinical signs of cutaneous vasculopathic rashes. The MRI abnormalities were notable, encompassing marrow oedema primarily affecting metaphyses and epiphyses, displaying broad transition zones. Soft tissue swelling and cortical erosions were also observed. These MRI features proved more pathognomonic in the acute clinical context. The study concluded that phalangeal microgeodic syndrome, characterised by digital swelling and erythema, might not be adequately assessed by plain X-rays. The more comprehensive MRI features, including marrow oedema and soft tissue abnormalities, appeared to be more indicative in diagnosing the condition. Considering the rarity of this syndrome and its temporal association with the COVID-19 pandemic, the study hypothesised that COVID-related thrombophilia and immune-mediated vasculopathy might act as crucial triggers for the active bony manifestations seen in this syndrome. KEY POINTS: • PMS is a rare, predominantly paediatric condition, of unknown aetiology which affects the digits. • Laboratory investigations are generally negative; however, in the appropriate clinical context, the X-ray findings of microgeodes and pattern of bone marrow oedema seen on MRI are pathognomonic. • Considering the rarity of PMS and temporal association with the COVID-19 pandemic, COVID vasculopathy may represent a previously unrecognised aetiology for PMS.

Phalangeal microgeodic syndrome: case report of a young woman treated with pentoxifylline.

Phalangeal microgeodic syndrome (PMS) is a rare osteolytic disorder of unknown etiology that typically affects children up to 15 years old during colder months. Transient peripheral circulatory impairment probably underlines its pathogenesis. Conservative treatment with eviction of cold exposure is often successful. We report the case of a young woman presenting with joint pain in her feet, along with toe discoloration and redness, where a diagnosis of PMS was established based on magnetic resonance imaging findings and exclusion of other differential diagnostic entities. Pharmacological treatment was deemed necessary for symptomatic relief, but a trial of calcium channel blocker (CCB) was not tolerated by the patient. The patient was then started on pentoxifylline, with significant clinical improvement.

Acro-osteolysis: imaging, differential diagnosis, and disposition review.

Acro-osteolysis is the osseous destruction of the hand or foot distal phalanges. The categories of the disease include terminal tuft, midshaft, or mixed types. Recognition of acro-osteolysis is straightforward on radiographs, but providing an accurate differential diagnosis and appropriately recommending advanced imaging or invasive tissue diagnosis can be more elusive. A radiologist's ability to provide advanced assessment can greatly aid clinicians in expedient diagnosis and management of the array of diseases presenting with acro-osteolysis.

Osteoid osteoma in the bones of the hand: a systematic literature review.

INTRODUCTION: Osteoid osteoma (OO) is a common benign bone tumor. OO is observed most frequently in the long bones, especially in the tibia and femur. When occurring in the bones of the hand, OO can be a diagnostic and therapeutic challenge. The aim of this study was to provide a systematic review of occurrence, symptoms, diagnosis and treatment options regarding OO in hand bones. MATERIALS AND METHODS: We performed a systematic review of the literature. All studies from the online databases PubMed and SpringerLink, which reported cases of osteoid osteomas in the bones of the hand, were included. By summarizing the literature, we evaluated the localization within the hand as well as diagnostic and therapeutic options. RESULTS: We included 133 studies reporting 401 cases. OO was mostly common in the phalanges. The diagnosis was mostly made by CT (computed tomography) scan. Most of the OO were treated surgically by open curettage or en bloc resection. CONCLUSIONS: Osteoid osteomas in the bones of the hand are rare and a delayed diagnosis is common. In cases of pain combined with particular symptoms such as nail hypertrophy and swelling OO should be considered. Of the most used imaging methods, CT scans have the highest sensitivity.

Development and function explain the modular evolution of phalanges in gecko lizards.

Selective regimes favouring the evolution of functional specialization probably affect covariation among phenotypic traits. Phalanges of most tetrapods develop from a conserved module that constrains their relative proportions. In geckos, however, biomechanical specializations associated with adhesive toepads involve morphological variation in the autopodium and might reorganize such modular structures. We tested two hypotheses to explain the modular architecture of hand bones in geckos, one based on developmental interactions and another incorporating functional associations related to locomotion, and compared the empirical support for each hypothetical module between padded and padless lineages. We found strong evidence for developmental modules in most species, which probably reflects embryological constraints during phalangeal formation. Although padded geckos exhibit a functional specialization involving the hyperextension of the distal phalanges that is absent in padless species, the padless species are the ones that show a distal functional module with high integration. Some ancestrally padless geckos apparently deviate from developmental predictions and present a relatively weak developmental module of phalanges and a strongly integrated distal module, which may reflect selective regimes involving incipient frictional adhesion in digit morphology. Modularity of digit elements seems dynamic along the evolutionary history of geckos, being associated with the presence/absence of adhesive toepads.

Hypothesis: Symbrachydactyly.

The term symbrachydactyly has been used for the phenotype of two or three short fingers or toes, hypoplasia of the middle and distal phalanges and variable syndactyly of the affected digits. Some clinicians have extended this diagnosis to include other phenotypes, specifically cleft hand, terminal transverse limb defects, hypoplasia of the thumb and fifth finger with nubbins for fingers 2, 3, and 4 and the hand deformity of the Poland anomaly. A malformations surveillance program can identify enough affected infants to characterize a phenotype. In the Active Malformations Surveillance Program in Boston (1972-2012) among 289,365 births, all infants and fetuses with structural abnormalities were identified from reading the examination findings by the pediatricians and pathologists and the results of diagnostic tests. Liveborn and stillborn infants were included, as well as fetuses from elective terminations because of anomalies identified in prenatal testing. We present the findings in 14 infants, all liveborn, who had symbrachydactyly of one or both hands (n = 12) or feet (n = 2). We suggest restricting the term symbrachydactyly to this single phenotype to improve counseling and to focus future research on identifying the cause(s).

Numeric and morphological studies of the African lion (Panthera leo leo) pectoral limb.

BACKGROUND: The Importance of the appendicular skeleton in the conformation, shape and physiology of wild animals especially carnivores for adaptation and survival cannot be overemphasized, as limited and obsolete information on the bones of the forelimb necessitated this study. Matured adult African lions (Male and female) that weighed 173 kg and 112 kg were obtained at different times after post mortem examinations of their carcasses. Bone preparation was achieved via cold water maceration after proper skin and muscle removal to a barest minimum. RESULTS: The acromion process of the scapula consisted of a ventral hamate and caudal suprahamate processes. The Clavicle was absent in this species. The musculospiral groove of the humerus was more or less absent while its supracondyloid foramen and crest were positioned above the medial condyle and lateral condyle respectively. The radio-ulna presented a twisted appearance with the radius slightly curved thereby creating an extensive interosseous space that spanned its entire length. The seven (7) carpal bones were uniquely arranged in two rows while the 5 metacarpals anchored 5 digits with 3 phalanges except the first with 2 phalanges each. Two sesamoid bones were located on the ventral surface of each Metacarpophalangeal joint. None was seen on its dorsal surface. The 3rd phalanx had a unique appearance with a crescent plate projecting from the ventral cavity. The average total number of bones constituting the pectoral limb was 80. CONCLUSION: Numerical information and detailed anatomical features of the pectoral limb bones of the African lion (Panthera leo leo) have added some valuable literature to science. This further serves as a baseline data for future scientific exposition on this species.

Human thumb consists of three phalanges and lacks metacarpal? A morphometric study on the long bones of the hand.

PURPOSE: For many years, it was thought that the thumb consists of just two phalanges that differentiate it from the other four medial triphalangeal fingers. But there are some old reports that few former scientists believed the thumb has three phalanges and it lacked a metacarpal, and the thumb metacarpal is a phalanx. So this anthropometric study was carried out by investigating the morphology of the long bones of the hand and correlations between the thumb metacarpal and other miniature long bones of the hand. METHODS: We studied anterior-posterior X-ray images of the right hands of 80 individuals from 18 to 65 years old. The exploration targets were the length of all metacarpals (MC), proximal phalanges (PP), middle phalanges (MP), and distal phalanges (DP). Friedman Repeated Measures Analysis of Variance and Dunn's post hoc test were carried out to compare the means of all variables. The correlation between all quantitative factors was done by Spearman Rank Correlation (Spearman's Rho) coefficient. RESULTS: Our results showed that the length of the phalanges and the total length of the fingers are independent of the related metacarpal length (P < 0.001). Also, the thumb metacarpal length in comparison to all bones of the hand was significantly different from all long bones of the hand except the proximal phalanx of the middle finger (P = 1). CONCLUSION: Based on the morphology of the long bones of the hand and the high similarity between the thumb metacarpal and phalanges especially the proximal phalanx of the middle finger, it can be suggested that the current thumb metacarpal is a proximal phalanx of the thumb.

Fibular Strut Arthrodesis for Salvage of Campanacci Grade III Giant Cell Tumor of the Hallucal Proximal Phalanx: A Case Report.

Involvement of toe phalanges by giant cell tumor (GCT) is extremely rare; tumors in these locations tend to be aggressive. Whereas aggressive GCTs of the distal phalanx may be managed successfully by en-bloc resection without reconstruction or amputation, management of these lesions, when they involve the proximal phalanx, can be challenging. We present a Campannaci grade III GCT of the hallucal proximal phalanx in a 14-year old girl that had breached into the dorsal soft tissues and the metatarso-phalangeal joint. Wide local resection of the proximal phalanx along with reconstruction arthrodesis with an autologous, non-vascularized fibular strut graft was performed. There was no recurrence at 3 years of follow-up. The patient had an excellent functional outcome. To the best of our knowledge, this is the first case reporting the outcomes of fibular strut arthrodesis for salvage of GCT of the hallucal proximal phalanx.

A single-cell transcriptomic atlas of the developing chicken limb.

BACKGROUND: Through precise implementation of distinct cell type specification programs, differentially regulated in both space and time, complex patterns emerge during organogenesis. Thanks to its easy experimental accessibility, the developing chicken limb has long served as a paradigm to study vertebrate pattern formation. Through decades' worth of research, we now have a firm grasp on the molecular mechanisms driving limb formation at the tissue-level. However, to elucidate the dynamic interplay between transcriptional cell type specification programs and pattern formation at its relevant cellular scale, we lack appropriately resolved molecular data at the genome-wide level. Here, making use of droplet-based single-cell RNA-sequencing, we catalogue the developmental emergence of distinct tissue types and their transcriptome dynamics in the distal chicken limb, the so-called autopod, at cellular resolution. RESULTS: Using single-cell RNA-sequencing technology, we sequenced a total of 17,628 cells coming from three key developmental stages of chicken autopod patterning. Overall, we identified 23 cell populations with distinct transcriptional profiles. Amongst them were small, albeit essential populations like the apical ectodermal ridge, demonstrating the ability to detect even rare cell types. Moreover, we uncovered the existence of molecularly distinct sub-populations within previously defined compartments of the developing limb, some of which have important signaling functions during autopod pattern formation. Finally, we inferred gene co-expression modules that coincide with distinct tissue types across developmental time, and used them to track patterning-relevant cell populations of the forming digits. CONCLUSIONS: We provide a comprehensive functional genomics resource to study the molecular effectors of chicken limb patterning at cellular resolution. Our single-cell transcriptomic atlas captures all major cell populations of the developing autopod, and highlights the transcriptional complexity in many of its components. Finally, integrating our data-set with other single-cell transcriptomics resources will enable researchers to assess molecular similarities in orthologous cell types across the major tetrapod clades, and provide an extensive candidate gene list to functionally test cell-type-specific drivers of limb morphological diversification.

Neandertal foot remains from Regourdou 1 (Montignac-sur-Vézère, Dordogne, France).

Regourdou is a well-known Middle Paleolithic site which has yielded the fossil remains of a minimum of two Neandertal individuals. The first individual (Regourdou 1) is represented by a partial skeleton while the second one is represented by a calcaneus. The foot remains of Regourdou 1 have been used in a number of comparative studies, but to date a full description and comparison of all the foot remains from the Regourdou 1 Neandertal, coming from the old excavations and from the recent reanalysis of the faunal remains, does not exist. Here, we describe and comparatively assess the Regourdou 1 tarsals, metatarsals and phalanges. They display traits observed in other Neandertal feet, which are different from some traits of the Sima de los Huesos (Atapuerca) hominins and of Middle Paleolithic, Upper Paleolithic and recent modern humans. These Neandertal features are: a rectangular talar trochlea with a large lateral malleolar facet, a broad talar head, a broad calcaneus with a projecting sustentaculum tali, a wide and wedged navicular with a projecting medial tubercle, large and wide bases of the lateral metatarsals, and mediolaterally expanded and robust phalanges that also show hallux valgus in a strongly built hallux.

Three-Dimensional Geometry of Phalanges as a Proxy for Pair-Matching: Mesh Comparison Using an ICP Algorithm.

Forensic anthropologists are frequently faced with the challenge of individualizing and sorting commingled remains in a variety of scenarios. A number of protocols have been proposed to standardize the methodological approach to individuating commingled remains, some of which are focused on pair-matching. A recent study by Karell et al. (2016) proposed a virtual method for pair-matching humeri using a semi-automatic procedure that gave encouraging results. With regards to the phalanges, there are only a handful of studies focusing on identifying and siding phalanges, as well as exploring their directional and functional asymmetry. Yet, they are still as important as every other bone when sorting commingled human remains in various situations, such as archaeological common burials and mass graves, commingled decomposed remains resulting from atrocities, accidents or natural disasters. This study investigates a new method for pair-matching, a common individualization technique, using digital three-dimensional models of bone: mesh-to-mesh value comparison (MVC) as proposed by Karell et al. (2016). The MVC method digitally compares the entire three-dimensional geometry of two bones using an iterative closest point (ICP) algorithm to produce a single value as a proxy for their similarity. The method is automated with the use of Viewbox software 4.1 beta for a simultaneous comparison of all possible pairs. For this study, 515 phalanges from 24 individuals of mixed ancestry were digitized using CT scans and the 3D modeling program AMIRA 5.3.3. The models were also hollowed (internal information of compact and trabecular bone removed) to test the method with simulated surface scan models. The subsequent data-over 73,000 comparisons-were assessed using sensitivity and specificity rates via ROC analysis to indicate how well the automated version of MVC pair-matched phalanges. The best bone in terms of pair-matching was the proximal phalanx of Digit 3 with 87.5% sensitivity and 92.4% specificity rates at a threshold value of 0.488 for the unhollowed bones. The specificity drops slightly (91.1%) when the hollowed models are compared. To compare the performance of the method in all phalanges, the specificity was set to 95%-allowing for a 5% acceptable error-and the adjusted sensitivity was compared. The highest sensitivity, namely 68.8%, was noted for Digit 2 proximal phalanx for both unhollowed and hollowed models. Thus far, our preliminary results indicate that the MVC method performs well when pair-matching phalanges, though it is less accurate than pair-matching other types of bones. The introduction of 95% specificity threshold allows for rejecting pairs in great confidence, which could, for instance, significantly reduce the number of DNA comparisons required for the remaining possible matches. In addition, the similar results obtained from hollowed and unhollowed models indicate that the internal information included in the unhollowed models adds little to the identification of true pairs. This means that if a CT scan is not available, the method could be applied to surface models produced by light and laser scanners as well. While additional work needs to be done to verify these preliminary results, this research has the potential to expand the repertoire of individualization methods.

Quantitative Ultrasound Measurement at the Hand Phalanges Does Not Reveal Skeletal Disturbances in Children With Bronchial Asthma: A Longitudinal Observation.

OBJECTIVES: To assess the skeletal status in asthmatic children treated with inhaled corticosteroids in a longitudinal observation by quantitative ultrasound (US) measurement at the hand phalanges. METHODS: Thirty-four children were studied prospectively. Quantitative US measurements were performed at baseline and after a mean ± SD of 2.35 ± 0.20 years. The obtained results were compared to age-, sex-, and body size-matched control participants selected from a database of previously examined healthy children. Individual changes in the amplitude-dependent speed of sound (Ad-SoS) during the follow-up period were also analyzed. RESULTS: The mean age of the asthmatic children was 10.6 ± 2.5 years. The mean Ad-SoS in the asthmatic children at baseline was 1940.5 ± 49.6 m/s, and the mean Z score was -0.26 ± 0.80. Corresponding values at the follow-up examination were 1976.2 ± 63.6 m/s and -0.18 ± 1.16. The results did not differ significantly in comparison to the healthy controls. The analysis of individual changes in Ad-SoS revealed that 18 participants had a significant increase in this parameter (ie, exceeding the least significant change threshold), and 16 did not have a significant change in their values. No one had a significant decrease in Ad-SoS. CONCLUSIONS: Quantitative US at the hand phalanges applied as a diagnostic tool revealed no essential differences in the pattern of skeletal development between asthmatic children treated with inhaled glucocorticosteroids and healthy controls.

Diffuse phalangeal signal abnormality on magnetic resonance imaging: phalangeal microgeodic disease.

BACKGROUND: Phalangeal microgeodic disease is a rare and benign self-limited condition involving the phalanges, often in the setting of cold exposure, with characteristic MR imaging abnormalities. Radiographic case descriptions are predominantly from Asia and Europe, with only seven cases using MR to characterize phalangeal microgeodic disease. OBJECTIVE: In this study we describe the MR imaging appearance of unusual and striking phalangeal signal abnormality compatible with phalangeal microgeodic disease at our institution in North America. MATERIALS AND METHODS: We retrospectively reviewed cases presenting at our institution with unusual or unexplained phalangeal signal abnormalities between 2001 and 2014. We reviewed the MR imaging appearances in conjunction with radiographs and any other available imaging investigations. RESULTS: Of 189 examinations reviewed during the study period, 8 imaging studies in 6 patients met the study inclusion criteria. Signal abnormality was present in 57 of 112 phalanges (51%), frequently involving the distal phalanges (70%, 28 of 40), followed by the middle phalanges (56%, 18 of 32) and the proximal phalanges (28%, 11 of 40). The pattern of involvement was most commonly diaphysis (38%), followed by metaphysis (32%) and epiphysis (30%). The extent of MR signal abnormality was greater than that suspected based on clinical presentation or on radiographs. CONCLUSION: The presence of unexplained diffuse characteristic marrow involvement of multiple painful phalanges on MR images, often in the setting of cold exposure, should raise the possibility of phalangeal microgeodic disease. Consideration of this diagnosis based on MR findings would lead to a more conservative management and avoid unnecessary invasive diagnostic procedures.

An unusual presentation of postaxial polydactyly of the foot.

A 6-month-old Caucasian baby is described with a postaxial polydactyly of the letf foot. Radiographic examination revealed the accessory digit was composed of soft tissue, some with a tiny osseous element, originated from around the metatarsophalangeal joint, defined by floating type (FT). The parents had consistent difficulty putting shoes. We encountered an exceedingly rare presentation of FT, to our inspection, had neither been previously related in published studies. To the best of our knowledge, this represents the unusual case of congenital deformity lesion on the left foot to be reported in the medical literature.

Abnormal Bone Marrow Signal Intensity in the Phalanges of the Foot as a Manifestation of Raynaud Phenomenon: A Report of Six Patients.

OBJECTIVE: The objectives of our study were to describe the MRI findings of pedal phalangeal bone marrow edema in patients with Raynaud phenomenon (RP) and discuss the clinical implications of these MRI findings. CONCLUSION: There is a progressive distal-to-proximal pattern of pedal phalangeal bone marrow edema on MRI in patients with RP. This knowledge may allow early diagnosis and treatment of rheumatologic disorders that are potentially associated with RP.

Early Pleistocene human hand phalanx from the Sima del Elefante (TE) cave site in Sierra de Atapuerca (Spain).

In this study, a new Early Pleistocene proximal hand phalanx (ATE9-2) from the Sima del Elefante cave site (TE - Sierra de Atapuerca, Spain), ascribed to Homo sp., is presented and comparatively described in the context of the evolution of the genus Homo. The ATE9-2 specimen is especially important because of the paucity of hand bones in the human fossil record during the Early Pleistocene. The morphological and metrical analyses of the phalanx ATE9-2 indicate that there are no essential differences between it and comparator fossil specimens for the genus Homo after 1.3 Ma (millions of years ago). Similar to Sima de los Huesos and Neandertal specimens, ATE9-2 is a robust proximal hand phalanx, probably reflecting greater overall body robusticity in these populations or a higher gracility in modern humans. The age of level TE9 from Sima del Elefante and morphological and metrical studies of ATE9-2 suggest that the morphology of the proximal hand phalanges and, thus, the morphology of the hand could have remained stable over the last 1.2-1.3 Ma. Taking into account the evidence recently provided by a metacarpal from Kaitio (Kenya) from around 1.42 Ma, we argue that modern hand morphology is present in the genus Homo subsequent to Homo habilis.

[Ainhum and "African acral keratoderma": three cases]. / Aïnhum et « kératodermies acrales africaines ¼ : trois cas.

BACKGROUND: Ainhum, or spontaneous dactylitis, involves the formation of a gradual constriction in the digital-plantar fold of the fifth toe that leads, after several years, to autoamputation of the digit. This condition is classically distinguished from "true" ainhum, of unknown aetiology and affecting only subjects of African origin, from "pseudo-ainhum", resulting from different causes such as inflammatory constriction or constriction by a foreign body, and finally from ainhumoid palmoplantar keratoderma, which is of genetic origin and occurs for instance in Vohwinkel syndrome. Herein, we report three cases of ainhum in women of sub-Saharan African origin; in addition, all three subjects were also presenting various forms of hyperkeratosis of the hands and feet known to primarily affect subjects of African origin. PATIENTS AND METHODS: The three patients, aged 30, 48 and 44 years, were respectively from Mali, Guinea and Senegal. They had consulted a dermatologist for violent pain in the fifth toe, which frequently prevented sleep and was inexplicable despite several consultations, and even in one case in spite of surgical investigation. Once the diagnosis had been made, relief was promptly provided for all three patients through Z-plasty to remove the circular constriction around the toe in question. In addition to ainhum, the first patient was also presenting diffuse palmoplantar keratoderma, together with an aspect of acrokeratoelastoidosis on the edges of her hands and feet, and knuckle pads, while the second was presenting diffuse palmoplantar keratoderma and an aspect of marginal acrokeratoelastoidosis, and the third was presenting small knuckle pads. DISCUSSION: A recent study has confirmed the high incidence of several forms of palmoplantar keratoderma of African origin, as well as frequent association of these different varieties with one another. These consist of diffuse keratoderma having a relatively non-specific aspect, keratoderma punctata of the palmar creases, marginal keratoderma known also as focal acral hyperkeratosis, and acrokeratoelastoidosis, despite the absence of histological evidence, and finally, inverted keratoderma, i.e. affecting the dorsal aspects of the extremities, such as knuckle pads. In the three cases presented here, ainhum was associated with these different forms of acral keratoderma seen chiefly in subjects of African origin. CONCLUSION: So-called "true" ainhum may be included in a broader group of African acral keratoderma, further reinforcing the unity of this group. Genetic studies are required to enable validation and refinement of these clinical findings.

First discovery of postcranial bones of Ouranopithecus macedoniensis (Primates, Hominoidea) from the late Miocene of Macedonia (Greece).

Two well preserved phalanges, one proximal and one intermediate, are identified and described. They constitute the first postcrania ever described of Ouranopithecus macedoniensis (Primates, Hominoidea) from the late Miocene locality of Ravin de la Pluie (RPl), Macedonia (Greece). They are isolated specimens, and the only ones known for their genus. The hypotheses that these specimens derive either from the hand or from the foot were tested. Comparisons with living apes of known positional behaviour were made to assess the functional signal in these specimens. The proximal phalanx, either manual or pedal, closely matches the proximal phalanges of terrestrial quadrupedal primates or the bipedal primate Homo. With respect to the intermediate phalanx we show that it closely matches phalanges of quadrupedal terrestrial primates. The terrestriality of Ouranopithecus, here reconstructed from phalangeal remains, is in agreement with our previous results of dental studies (thick check teeth enamel and microwear pattern of incisors and molars), which indicate that it was a hard object feeder living near the ground.