-
Journal of Hand Surgery Global Online Jul 2021Isolated volar metacarpophalangeal dislocations of fingers are extremely rare. There are few cases published in English and French literature. In this article, we aim to...
Isolated volar metacarpophalangeal dislocations of fingers are extremely rare. There are few cases published in English and French literature. In this article, we aim to review the literature and present a case of isolated open volar dislocation of a finger. We treated this dislocation first by a dorsal approach alone and later, after recurrence, using a combined dorsal and volar approach. This report emphasizes the pathology of such injuries, clarifies the mechanisms, and outlines the treatment options of the dislocations. Close reduction can be achieved and maintained if done early. It must be attempted first for all cases. In irreducible or reducible but unstable dislocations, we recommend surgical restoration. During an open reduction, the major torn or avulsed soft tissue joint stabilizers must be repaired. A combined dorsal and volar approach, starting dorsally, is useful.
PubMed: 35415557
DOI: 10.1016/j.jhsg.2021.04.001 -
PloS One 2017The objective of this study was to assess beak shape variation in domestic turkeys (Meleagris gallopavo) and determine the effects of age, sex, and beak size on beak...
The objective of this study was to assess beak shape variation in domestic turkeys (Meleagris gallopavo) and determine the effects of age, sex, and beak size on beak shape variation using geometric morphometrics. Dorsal and right lateral images were taken of 2442 turkeys at 6 and 18.5 weeks of age. Landmarks were digitized in tpsDig in three analyses of the dorsal upper mandible, lateral upper mandible, and lateral lower mandible shape of each turkey at both ages. The coordinate data were then subjected to a principal components analysis (PCA), multivariate regression, and a canonical variates analysis (CVA) with a Procrustes ANOVA in MorphoJ. For the dorsal images, three principal components (PCs) showed beak shape variation ranged from long, narrow, and pointed to short, wide, and blunt upper mandibles at both ages (6 weeks: 95.36%, 18.5 weeks: 92.21%). Three PCs showed the lateral upper mandible shape variation ranged from long, wide beaks with long, curved beak tips to short, narrow beaks with short, pointed beak tips at both ages (6 weeks: 94.91%, 18.5 weeks: 94.33%). Three PCs also explained 97.80% (6 weeks) and 97.11% (18.5 weeks) of the lateral lower mandible shape variation ranging from wide and round to narrow and thin lower mandibles with superior/inferior beak tip shifts. Beak size accounted for varying proportions of the beak shape variation (0.96-54.76%; P < 0.0001) in the three analyses of each age group. For all the analyses, the CVA showed sexual dimorphism in beak shape (P < 0.0001) with female upper mandibles appearing wider and blunter dorsally with long, curved beak tips laterally. Whereas male turkey upper mandibles had a narrow, pointed dorsal appearance and short, pointed beak tips laterally. Future applications of beak shape variability could have a genetic and welfare value by incorporating beak shape variation to select for specific turkey beak phenotypes as an alternative to beak treatment.
Topics: Animals; Beak; Female; Male; Mandible; Turkeys
PubMed: 28934330
DOI: 10.1371/journal.pone.0185159 -
Royal Society Open Science Apr 2017All derived turtles are characterized by one of the strongest reductions of the dorsal elements among Amniota, and have only 10 dorsal and eight cervical vertebrae. I...
All derived turtles are characterized by one of the strongest reductions of the dorsal elements among Amniota, and have only 10 dorsal and eight cervical vertebrae. I demonstrate that the Late Triassic turtles, which represent successive stages of the shell evolution, indicate that the shift of the boundary between the cervical and dorsal sections of the vertebral column occurred over the course of several million years after the formation of complete carapace. The more generalized reptilian formula of at most seven cervicals and at least 11 dorsals is thus plesiomorphic for Testudinata. The morphological modifications associated with an anterior homeotic change of the first dorsal vertebra towards the last cervical vertebra in the Triassic turtles are partially recapitulated by the reduction of the first dorsal vertebra in crown-group Testudines, and they resemble the morphologies observed under laboratory conditions resulting from the experimental changes of gene expression patterns. This homeotic shift hypothesis is supported by the, unique to turtles, restriction of expression domains, somitic precursors of scapula, and brachial plexus branches to the cervical region, by the number of the marginal scute-forming placodes, which was larger in the Triassic than in modern turtles, and by phylogenetic analyses.
PubMed: 28484613
DOI: 10.1098/rsos.160933 -
Veterinary and Comparative Orthopaedics... Sep 2023The aim of this study was to define landmarks of the intermetatarsal channel of the dorsal pedal artery and to assess whether damage to the dorsal pedal artery during...
OBJECTIVES
The aim of this study was to define landmarks of the intermetatarsal channel of the dorsal pedal artery and to assess whether damage to the dorsal pedal artery during metatarsal screw placement in dogs undergoing pan- and partial-tarsal arthrodesis (PanTA/ParTA) could be a mechanism in the development of plantar necrosis.
STUDY DESIGN
This study was divided in to two parts: (1) ex-vivo anatomical study: 19 canine cadavers, (2) retrospective clinical study: 39 dogs. Cadaveric dissection documented the mean intermetatarsal channel position. Metatarsal screw position was evaluated on postoperative radiographs of dogs after PanTA or ParTA. Screw position, arthrodesis type and surgical approach were assessed for their impact on complications, including plantar necrosis.
RESULTS
The mean proximal and distal extent of the intermetatarsal channel lies between 4.3% ± 1.9 and 22.8% ± 2.9 the length of metatarsal III (MTIII) respectively. The intermetatarsal channel lies within the most proximal 25% of MTIII in 95% of cases. At least one screw risked damaging the mean intermetatarsal channel position in 92% of dogs; 8% of these dogs went on to develop plantar necrosis. The mean screw position did not differ between ParTA cases with or without plantar necrosis ( > 0.05).
CONCLUSION
Violation of the intermetatarsal channel is possible during metatarsal screw placement. Care should be taken when placing screws in the proximal 25% of the metatarsals, specifically avoiding exiting dorsally between MTII and MTIII and across the distal region of the intermetatarsal channel, where the perforating metatarsal artery passes interosseously, as damage may contribute to the aetiology of plantar necrosis.
Topics: Dogs; Animals; Retrospective Studies; Metatarsal Bones; Metatarsus; Risk Factors; Arthrodesis; Cadaver; Dog Diseases
PubMed: 37142232
DOI: 10.1055/s-0043-57222 -
American Journal of Veterinary Research Jan 2024To describe the acquisition and pitfalls of a 3-view transesophageal echocardiography (TEE) protocol in anesthetized, dorsally recumbent dogs.
OBJECTIVE
To describe the acquisition and pitfalls of a 3-view transesophageal echocardiography (TEE) protocol in anesthetized, dorsally recumbent dogs.
ANIMALS
8 beagles, 1 to 2 years old, 7.4 to 11.2 kg.
METHODS
Dogs were anesthetized, mechanically ventilated, and placed in dorsal recumbency. A TEE probe was advanced, and 3 views were performed: midesophageal 4-chamber and long axis (ME 4C and ME LAX) and caudal esophageal short axis (CE SAX) at the level of the papillary muscles. Probe insertion depth, flexion, omniplane angle, and image acquisition time were recorded. Two observers assessed 24 video clips each and identified anatomical structures.
RESULTS
The ME 4C and ME LAX were obtained at 35 (30 to 40) cm insertion depth, omniplane at 0° and 103° (90 to 116), respectively. Views were obtained in ≤30 seconds once the TEE was in the cervical esophagus. Left-sided structures were identified in all cases, whereas right-sided structures were not always simultaneously obtained in the ME 4C, requiring further probe manipulation. All structures were identified on ME LAX. CE SAX was obtained at 40 (35 to 45) cm, omniplane at 0°, and in 15 (10 to 90) seconds. A true SAX view (circular left ventricle at the level of papillary muscles) could not be obtained in all dogs.
CLINICAL RELEVANCE
A 3-view TEE protocol using core views as those described in humans may be applicable to dogs under general anesthesia and in dorsal recumbency. The CE SAX view at the level of the papillary muscles appears more difficult to obtain with consistency than midesophageal views.
Topics: Humans; Animals; Dogs; Echocardiography, Transesophageal; Anesthesia, General; Heart Ventricles
PubMed: 38035479
DOI: 10.2460/ajvr.23.07.0176 -
Journal of Anatomy Nov 2013The tapetum lucidum is a light-reflective tissue in the eyes of many animals. Many ungulates have a fibrous tapetum. The horse has one of the largest eyes of any living...
The tapetum lucidum is a light-reflective tissue in the eyes of many animals. Many ungulates have a fibrous tapetum. The horse has one of the largest eyes of any living animal and also has excellent vision in low-light environments. This study aimed to clarify the macroscopic tapetal shape, relationship between the tapetal thickness and the degree of pigmentation of the retinal pigment epithelium (RPE), spatial relationship between the visual streak and the tapetum, and wavelength of the light reflected from the tapetum in the horse. Macroscopically, weak light revealed the tapetum as a horizontal band located dorsal to and away from the optic disc. The tapetum expanded dorsally as the illumination increased. The tapetal tissue consisted of lamellae of collagen fibrils running parallel to the retinal surface; these spread over almost the entire ocular fundus and were thicker in the horizontal band dorsal to the disc. Only the horizontal band of the tapetum was covered by unpigmented RPE, suggesting that this band reflects light and is responsible for mesopic and scotopic vision. The visual streak was located in the ventral part of the horizontal band, ventral to the thickest part of the tapetum. The wavelength of the light reflected from the horizontal band of the tapetum was estimated from the diameter and interfibrous distance of the collagen fibrils to be approximately 468 nm. Therefore, the light reflected from the tapetum should be more effectively absorbed by rods than by cones, and should not interfere with photopic vision.
Topics: Animals; Collagen; Eye; Horses; Pigmentation; Retinal Pigment Epithelium
PubMed: 24102505
DOI: 10.1111/joa.12100 -
Acta Neurochirurgica Feb 2018It is unclear which magnetic resonance imaging (MRI) sequence most accurately corresponds with the electrophysiological subthalamic nucleus (STN) obtained during... (Comparative Study)
Comparative Study
BACKGROUND
It is unclear which magnetic resonance imaging (MRI) sequence most accurately corresponds with the electrophysiological subthalamic nucleus (STN) obtained during microelectrode recording (MER, MER-STN). CT/MRI fusion allows for comparison between MER-STN and the STN visualized on preoperative MRI (MRI-STN).
OBJECTIVE
To compare dorsal and ventral STN borders as seen on 3-Tesla T2-weighted (T2) and susceptibility weighted images (SWI) with electrophysiological STN borders in deep brain stimulation (DBS) for Parkinson's disease (PD).
METHODS
Intraoperative CT (iCT) was performed after each MER track. iCT images were merged with preoperative images using planning software. Dorsal and ventral borders of each track were determined and compared to MRI-STN borders. Differences between borders were calculated.
RESULTS
A total of 125 tracks were evaluated in 45 patients. MER-STN started and ended more dorsally than respective dorsal and ventral MRI-STN borders. For dorsal borders, differences were 1.9 ± 1.4 mm (T2) and 2.5 ± 1.8 mm (SWI). For ventral borders, differences were 1.9 ± 1.6 mm (T2) and 2.1 ± 1.8 mm (SWI).
CONCLUSIONS
Discrepancies were found comparing borders on T2 and SWI to the electrophysiological STN. The largest border differences were found using SWI. Border differences were considerably larger than errors associated with iCT and fusion techniques. A cautious approach should be taken when relying solely on MR imaging for delineation of both clinically relevant STN borders.
Topics: Adult; Aged; Deep Brain Stimulation; Female; Humans; Intraoperative Neurophysiological Monitoring; Magnetic Resonance Imaging; Male; Middle Aged; Subthalamic Nucleus; Tomography, X-Ray Computed
PubMed: 29275518
DOI: 10.1007/s00701-017-3432-5 -
Hand (New York, N.Y.) Nov 2017The aim of this study was to compare the functional outcomes and complications of volar and dorsal plating for the management of intra-articular distal radius fractures,... (Comparative Study)
Comparative Study
BACKGROUND
The aim of this study was to compare the functional outcomes and complications of volar and dorsal plating for the management of intra-articular distal radius fractures, with special regard to indications for dorsal plating. Furthermore, we examine the rationale for choosing dorsal plating and its frequency of use.
METHODS
Clinical assessments included range of motion measurements at the wrist; grip strength; the Quick Disabilities of the Arm, Shoulder, and Hand score; and the Gartland and Werley score. Clinical results were compared with those achieved using a volarly placed locking plate system. According to Lutsky's plate theory, the rationale for choosing dorsal plating was based on 4 types of pathologic fractures.
RESULTS
Of 112 patients, 38 patients were treated with open reduction internal fixation via a dorsal approach and 68 patients were treated using a volar approach. Except for wrist flexion, there were no other statistical differences in the clinical results between groups for both subjective and objective parameters. There were no statistically significant differences in the complication rates between the volar and dorsal plated groups. One serious complication occurred after volar plating. The most common reason for choosing dorsal plating was irreducible dorsal die-punch fractures.
CONCLUSIONS
The treatment of displaced intra-articular distal radius fractures with a dorsally versus a volarly placed interlocking plate system demonstrated similar clinical results. Postoperative complications were not readily observed in the patients treated with a dorsal locking plate. Certain fracture patterns are more appropriately stabilized using a dorsal plate fixation.
Topics: Bone Plates; Disability Evaluation; Female; Fracture Fixation, Internal; Hand Strength; Humans; Male; Middle Aged; Open Fracture Reduction; Prospective Studies; Radius Fractures; Range of Motion, Articular
PubMed: 29091491
DOI: 10.1177/1558944716675129 -
Proceedings of the National Academy of... Dec 2015Winged insects underwent an unparalleled evolutionary radiation, but mechanisms underlying the origin and diversification of wings in basal insects are sparsely known...
Winged insects underwent an unparalleled evolutionary radiation, but mechanisms underlying the origin and diversification of wings in basal insects are sparsely known compared with more derived holometabolous insects. In the neopteran species Oncopeltus fasciatus, we manipulated wing specification genes and used RNA-seq to obtain both functional and genomic perspectives. Combined with previous studies, our results suggest the following key steps in wing origin and diversification. First, a set of dorsally derived outgrowths evolved along a number of body segments including the first thoracic segment (T1). Homeotic genes were subsequently co-opted to suppress growth of some dorsal flaps in the thorax and abdomen. In T1 this suppression was accomplished by Sex combs reduced, that when experimentally removed, results in an ectopic T1 flap similar to prothoracic winglets present in fossil hemipteroids and other early insects. Global gene-expression differences in ectopic T1 vs. T2/T3 wings suggest that the transition from flaps to wings required ventrally originating cells, homologous with those in ancestral arthropod gill flaps/epipods, to migrate dorsally and fuse with the dorsal flap tissue thereby bringing new functional gene networks; these presumably enabled the T2/T3 wing's increased size and functionality. Third, "fused" wings became both the wing blade and surrounding regions of the dorsal thorax cuticle, providing tissue for subsequent modifications including wing folding and the fit of folded wings. Finally, Ultrabithorax was co-opted to uncouple the morphology of T2 and T3 wings and to act as a general modifier of hindwings, which in turn governed the subsequent diversification of lineage-specific wing forms.
Topics: Animals; Evolution, Molecular; Gene Expression Regulation, Developmental; Genetic Variation; Genome, Insect; High-Throughput Nucleotide Sequencing; Insect Proteins; Insecta; RNA Interference; Reverse Transcriptase Polymerase Chain Reaction; Wings, Animal
PubMed: 26668365
DOI: 10.1073/pnas.1509517112 -
Scientific Reports Oct 2023Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of...
Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of diverse factors and conditions. The joints most often affected by traumatic osteoarthritis in dromedaries are the metacarpophalangeal and metatarsophalangeal joints. A comprehensive understanding of joint anatomy and topography of the dromedary is required to perform arthrocentesis correctly on affected joints. Forty-two distal limbs were taken from 28 camels and studied by gross dissection, casting, ultrasonography, and computed tomography (CT). Representative three-dimensional models of the joint cavities, recesses, and pouches were obtained using different casting agents. This study provides a detailed description of dorsally, axially, and abaxially positioned joint recesses, as well as palmar/plantar positioned joint pouches. The safety and feasibility of the different arthrocentesis approaches were evaluated. The traditional dorsal arthrocentesis approach of the metacarpophalangeal, metatarsophalangeal, proximal interphalangeal, and distal interphalangeal joints, has limitations due to the risk of damaging the tendon structures and articular cartilage, which can lead to joint degeneration. A lateral arthrocentesis approach via the proximal palmar/plantar pouches of the metacarpophalangeal/metatarsophalangeal and proximal interphalangeal joints is recommended. This approach eliminates the potential needle injury to the articulating joint cartilage and other surrounding joint structures, such as tendons, blood vessels, and nerves.
Topics: Animals; Camelus; Arthrocentesis; Forelimb; Joints; Cartilage, Articular; Metatarsophalangeal Joint
PubMed: 37833397
DOI: 10.1038/s41598-023-44391-1