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García-esponda, César M. - One of the best experts on this subject based on the ideXlab platform.
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Data from: Paleobiology of the basal hydrochoerine Cardiomys Ameghino, 1885 (Rodentia, Caviomorpha, late Miocene, South America) as inferred from its postcranial anatomy
2018Co-Authors: Candela, Adriana M., Muñoz, Nahuel A., García-esponda, César M.Abstract:Extinct Hydrochoerinae traditionally included within “Cardiomyinae” (Cavioidea, Caviidae) are caviomorph rodents well-represented in the late Miocene-late Pliocene of Argentina, but their paleobiology has been investigated little. The postcranium of these rodents is poorly-known and has not been considered in morpho-functional or systematic studies. Here, we provide the first description of the postcranium of the basal hydrochoerine Cardiomys Ameghino, 1885, based on a well preserved specimen from the late Miocene of Central Argentina, and evaluate its paleobiological and systematic implications. A morpho-functional study and a character mapping analysis were performed. We concluded that most of its postcranial features are neither adaptations to a specialized cursoriality, as in some extant cavioids, nor major modifications associated with swimming, as in extant capybaras. Cardiomys exhibits several features (high humeral distal articular surface, perforated Olecranon fossa, proximal radius cranially located with respect to the ulna, subrectangular-shaped radial head with flattened ulnar facet, calcaneocuboid joint distally located with respect to the astragalonavicular joint) that allow us to consider it as an ambulatory caviid. Among cavioids, some features of Cardiomys are more similar to those of Hydrochoerus Brisson, 1762 (lateral coronoid process reduced, humeral capitular tail well-differentiated, capitular tail facet of the radial head well-developed and relatively short craniodistally, plantar process of the navicular massive and short). Other postcranial features (relatively longer and more gracile Mt III and phalanges, straight caudal border of the ulna) suggest that Cardiomys would have been a generalized hydrochoerine, as was also indicated by its dental and cranial characters
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Paleobiology of the basal hydrochoerine Cardiomys Ameghino, 1885 (Rodentia, Caviomorpha, late Miocene, South America) as inferred from its postcranial anatomy
'Cambridge University Press (CUP)', 2018Co-Authors: Candela, Adriana Magdalena, Muñoz, Nahuel Antu, García-esponda, César M.Abstract:Extinct Hydrochoerinae traditionally included within 'Cardiomyinae' (Cavioidea, Caviidae) are caviomorph rodents well represented in the late Miocene to late Pliocene of Argentina, but their paleobiology has received little scientific attention. The postcranium of these rodents is poorly known and has not been considered in morphofunctional or systematic studies. Here, we provide the first description of the postcranium of the basal hydrochoerine Cardiomys Ameghino, 1885, based on a well-preserved specimen from the late Miocene of Central Argentina, and evaluate its paleobiological and systematic implications. A morphofunctional study and a character mapping analysis were performed. We concluded that most of its postcranial features are neither adaptations to a specialized cursoriality, as in some extant cavioids, nor major modifications associated with swimming, as in extant capybaras. Cardiomys exhibits several features (high humeral distal articular surface, perforated Olecranon fossa, proximal portion of radius cranially located with respect to the ulna, subrectangular-shaped radial head with flattened ulnar facet, calcaneocuboid joint distally located with respect to the astragalonavicular joint) that allow us to interpret it as an ambulatory caviid. Among cavioids, some features of Cardiomys are more similar to those of Hydrochoerus Brisson, 1762 (lateral coronoid process reduced, humeral capitular tail well differentiated, capitular tail facet of the radial head well developed and relatively short craniodistally, plantar process of the navicular massive and short). Other postcranial features (relatively longer and more gracile third metatarsal and phalanges, straight caudal border of the ulna) suggest that Cardiomys would have been a generalized hydrochoerine, as also indicated by its dental and cranial characters.Fil: Candela, Adriana Magdalena. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Muñoz, Nahuel Antu. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: García Esponda, César M.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Zoología Invertebrados; Argentin
David Stanley - One of the best experts on this subject based on the ideXlab platform.
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radiographic changes at the elbow in primary osteoarthritis a comparison with normal aging of the elbow joint
Journal of Shoulder and Elbow Surgery, 2007Co-Authors: Sam Dalal, Matthew J Bull, David StanleyAbstract:A retrospective case-control study was undertaken to evaluate the pathologic radiographic changes that occur in primary osteoarthritis of the elbow. The radiographs of 50 patients with primary osteoarthritis of the elbow were compared with an age- and sex-matched control group to distinguish those features specific to elbow osteoarthritis from those occurring as a result of normal aging. We assessed 100 radiographs (50 anteroposterior and 50 lateral views) in both the study and control groups for 10 radiographic features. In the osteoarthritic group, osteophytes of the Olecranon (96%), coronoid process (90%), radial head (86%), and coronoid and radial fossae (64%) were the most frequent findings. Joint space narrowing occurred predominantly at the radiocapitellar joint (58%) and was more common than at the ulnotrochlear joint (16%). Thickening of the Olecranon fossa membrane was noted in 68%. In the age- and sex-matched control group, coronoid osteophytes occurred in 36% of cases, but the other features were rarely observed.
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the histologic changes of the Olecranon fossa membrane in primary osteoarthritis of the elbow
Journal of Shoulder and Elbow Surgery, 2004Co-Authors: Kim S Suvarna, David StanleyAbstract:Eight randomly selected patients undergoing the Outerbridge-Kashiwagi (ulnohumeral arthroplasty) debridement procedure for primary osteoarthritis of the elbow had fenestration of the Olecranon fossa by use of a bone trephine. The cores of bone removed were compared histologically with age- and sex-matched controls derived from necropsy samples with no history of osteoarthritis. All components of the Olecranon fossa membrane (anterior cortical bone, medullary cavity, posterior cortical bone, and anterior and posterior fibrous tissue) were noted to be of increased thickness in those patients with osteoarthritis of the elbow when compared with the control group. With the exception of the anterior surface fibrous tissue, these differences were of statistical significance by use of the Wilcoxon signed rank test (anterior cortical bone, P =.01; medullary cavity, P =.01; posterior cortical bone, P =.02; and posterior surface fibrous tissue, P =.01). Bone volume was also measured in the two groups and was statistically greater in the patients with osteoarthritis compared with the control group (P =.01).
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arthroscopic fenestration of the Olecranon fossa in the treatment of osteoarthritis of the elbow
Arthroscopy, 1993Co-Authors: J F Redden, David StanleyAbstract:Summary A new arthroscopic approach to the treatment of elbow osteoarthritis that permits debridement of the elbow joint together with the removal of intraarticular loose bodies is described. Twelve patients (11 male, one female) with an age range of 29–64 (mean 47.5 years) underwent the procedure. Postsurgery all patients had relief of elbow-locking and experienced a reduction in elbow pain (follow-up 3–30 months, mean 16 months). The technique is offered as a treatment option for patients with elbow osteoarthritis.
David Ring - One of the best experts on this subject based on the ideXlab platform.
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non union of minimally displaced low transcondylar fracture of the distal humerus a report of three patients
Shoulder & Elbow, 2011Co-Authors: Alexander A Weening, David RingAbstract:Minimally displaced extra-articular bicolumnar fractures of the distal humerus at the level of the base of the Olecranon fossa (sometimes referred to as transcondylar fractures) are uncommon. Good results after both operatieve and non-operative treatment have been described, whereas other studies suggest that these fractures have a high risk to non-union. We describe three patients with non-union after a nondisplaced or minimally displaced low transcondylar (extra-articular) fracture of the distal humerus. Three relatively unique non-union cases are described with the aim of increasing awareness of the potential pitfalls associated with these fractures, suggesting that these fractures merit caution and additional study.
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osteonecrosis after open reduction and internal fixation of a bicolumnar fracture of the distal humerus a report of four cases
Journal of Hand Surgery (European Volume), 2011Co-Authors: Jimme K Wiggers, David RingAbstract:Four cases with osteonecrosis of the trochlea after open reduction and internal fixation of a fracture involving both the medial and lateral columns of the distal humerus above the base of the Olecranon fossa (a bicolumnar fracture of the distal humerus) are reported to bring attention to this complication.
D A Waters - One of the best experts on this subject based on the ideXlab platform.
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locked intramedullary nailing of humeral shaft fractures implant design surgical technique and clinical results
Journal of Bone and Joint Surgery-british Volume, 1994Co-Authors: A M Ingman, D A WatersAbstract:We report our experience with a modified implant and a new technique for locked intramedullary nailing of the humerus in 41 patients. Locking was by cross-screws placed from lateral to medial in the proximal humerus, and anteroposteriorly in the distal humerus. Early in the series, 11 nails were inserted at the shoulder, but we found that rehabilitation was faster after retrograde nailing through the Olecranon fossa, which was used for the other 30. We used a closed technique for 29 of the nailings. Of the 41 patients treated, 21 had acute fractures, five had nonunion, and 15 had pathological fractures. Secure fixation was obtained for comminuted and osteoporotic fractures in any part of the humeral shaft, which allowed the early use of crutches and walking frames. Two nails were locked at only one end, and one of these became the only failure of union after an acute fracture.
Jimme K Wiggers - One of the best experts on this subject based on the ideXlab platform.
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osteonecrosis after open reduction and internal fixation of a bicolumnar fracture of the distal humerus a report of four cases
Journal of Hand Surgery (European Volume), 2011Co-Authors: Jimme K Wiggers, David RingAbstract:Four cases with osteonecrosis of the trochlea after open reduction and internal fixation of a fracture involving both the medial and lateral columns of the distal humerus above the base of the Olecranon fossa (a bicolumnar fracture of the distal humerus) are reported to bring attention to this complication.
