A new short-faced archosauriform from the Upper Triassic Placerias/Downs’ quarry complex, Arizona, USA, expands the morphological diversity of the Triassic archosauriform radiation

The Placerias/Downs’ Quarry complex in eastern Arizona, USA, is the most diverse Upper Triassic vertebrate locality known. We report a new short-faced archosauriform, Syntomiprosopus sucherorum gen. et sp. nov., represented by four incomplete mandibles, that expands that diversity with a morphology unique among Late Triassic archosauriforms. The most distinctive feature of Syntomiprosopus gen. nov. is its anteroposteriorly short, robust mandible with 3–4 anterior, a larger caniniform, and 1–3 “postcanine” alveoli. The size and shape of the alveoli and the preserved tips of replacement teeth preclude assignment to any taxon known only from teeth. Additional autapomorphies of S. sucherorum gen. et sp. nov. include a large fossa associated with the mandibular fenestra, an interdigitating suture of the surangular with the dentary, fine texture ornamenting the medial surface of the splenial, and a surangular ridge that completes a 90° arc. The external surfaces of the mandibles bear shallow, densely packed, irregular, fine pits and narrow, arcuate grooves. This combination of character states allows an archosauriform assignment; however, an associated and similarly sized braincase indicates that Syntomiprosopus n. gen. may represent previously unsampled disparity in early-diverging crocodylomorphs. The Placerias Quarry is Adamanian (Norian, maximum depositional age ~219 Ma), and this specimen appears to be an early example of shortening of the skull, which occurs later in diverse archosaur lineages, including the Late Cretaceous crocodyliform Simosuchus. This is another case where Triassic archosauriforms occupied morphospace converged upon by other archosaurs later in the Mesozoic and further demonstrates that even well-sampled localities can yield new taxa.

The medial tangent of the proximal tibia is a suitable extra-articular landmark in determining the tibial anteroposterior axis

Background Tibial rotational alignment in total knee arthroplasty (TKA) is generally determined based on intra-articular structure, and can be difficult to ascertain in some cases. The aim of this study was to investigate whether the medial tangent angle of the tibia (MTAT) could be useful in determining the anteroposterior axis of the tibia. Methods This study was performed on 103 lower limbs in 53 patients who underwent primary total hip arthroplasty. The selection criteria for our study were based on the assumption that knees in patients undergoing THA exhibit fewer degenerative changes than knees in patients undergoing TKA. Using computed tomography images, the MTAT, comprising the medial tangent of the proximal tibia and the anteroposterior (AP) axis of the tibia, was measured on three horizontal planes: at the distal edge of the tibial tubercle (A), at 5 cm distally (B), and at 10 cm further distally (C). The tibial medial surface was grouped into three classes according to shape: valley type, flat type, and hill type. The percentage at which these shapes were observed in each group was also calculated. Measurement reliability was calculated using the intraclass correlation coefficient. Results The angles were 45.2° (interquartile range: IR 43.0–47.7) at A, 42.7° (IR 38.7–45.9) at B, and 42.4° (IR 38.2–45.9) at C. Intra-rater reliability and inter-rater reliability was 0.982 and 0.974 at A, 0.810 and 0.411 at B, and 0.940 and 0.811 at C, respectively. Regarding the tibial medial surface, the valley type was observed in all cases at A, and the hill type was observed in the highest percentage of cases at B and C. Conclusions The MTAT was approximately 45° at level A, and reproducibility was the highest among the three groups. The two points forming the valley on the tibial medial surface were bony ridges. Therefore, the medial tangent of the tibia at level A could be easily determined. Because the distal edge of the tibial tubercle exists at the surgical area and the extra-articular area, it can be a suitable intraoperative, extra-articular landmark in determining the tibial AP axis, even for revision TKA.

The Medial Tangent of the Proximal Tibia Is a Suitable Extra-articular Landmark in Determining the Tibial Anteroposterior Axis

Background: Tibial rotational alignment in total knee arthroplasty (TKA) is generally determined based on intra-articular structure, and can be difficult to ascertain in some cases. The aim of this study was to investigate whether the medial tangent angle of the tibia (MTAT) could be useful in determining the anteroposterior axis of the tibia.Methods: This study was performed on 103 lower limbs in 53 patients who underwent primary total hip arthroplasty. The selection criteria for our study were based on the assumption that knees in patients undergoing THA exhibit fewer degenerative changes than knees in patients undergoing TKA. Using computed tomography images, the MTAT, comprising the medial tangent of the proximal tibia and the anteroposterior (AP) axis of the tibia, was measured on three horizontal planes: at the distal edge of the tibial tubercle (A), at 5 cm distally (B), and at 10 cm further distally (C). The tibial medial surface was grouped into three classes according to shape: valley type, flat type, and hill type. The percentage at which these shapes were observed in each group was also calculated. Measurement reliability was calculated using the intraclass correlation coefficient.Results: The angles were 45.2° (interquartile range: IR 43.0-47.7) at A, 42.7° (IR 38.7-45.9) at B, and 42.4° (IR 38.2-45.9) at C. Intra-rater reliability and inter-rater reliability was 0.982 and 0.974 at A, 0.810 and 0.411 at B, and 0.940 and 0.811 at C, respectively. Regarding the tibial medial surface, the valley type was observed in all cases at A, and the hill type was observed in the highest percentage of cases at B and C.Conclusions: The MTAT was approximately 45° at level A, and reproducibility was the highest among the three groups. The two points forming the valley on the tibial medial surface were bony ridges. Therefore, the medial tangent of the tibia at level A could be easily determined. Because the distal edge of the tibial tubercle exists at the surgical area and the extra-articular area, it can be a suitable intraoperative, extra-articular landmark in determining the tibial AP axis, even for revision TKA.

INVESTIGATION OF LOCALIZED SKIN TEMPERATURE DISTRIBUTION ACROSS THE TRANSTIBIAL RESIDUAL LIMB

BACKGROUND: Interventions to resolve thermal discomfort as a common complaint in amputees are usually chosen based on the residual limb skin temperature while wearing prosthesis; whereas, less attention has been paid to residual limb skin temperature while outside of the prosthesis. The objective of this study was to explore the localized and regional skin temperature over the transtibial residual limb (TRL) while outside of the prosthesis. METHODOLOGY: Eight unilateral transtibial adults with traumatic amputation were enrolled in this cross-sectional study. Participants sat to remove their prostheses and rested for 30 minutes. Twelve sites were marked circumferentially in four columns (anterolateral, anteromedial, posteromedial, and posterolateral) and longitudinally in three rows (proximal, middle, and distal) over the residual limb and used for attachment of analog thermistors. Skin temperature was recorded and compared for 11 minutes. Furthermore, the relationship of skin temperature with participants’ demographic and clinical characteristics was explored. FINDINGS: The whole temperature of the TRL was 27.73 (SD=0.83)°C. There was a significant difference in skin temperature between anterior and posterior columns. Likewise, the distal row was significantly different from the proximal and middle rows. The mean temperature at the middle and distal zones of the anteromedial column had the highest and lowest skin temperatures (29.8 and 26.3°C, p<0.05), respectively. The mean temperature of the whole TRL had no significant relationships (p>0.05) with participants’ demographic and clinical characteristics. CONCLUSIONS: An unequal distribution of temperature over the TRL was found with significantly higher and lower temperatures at its anterior column and distal row, respectively. This temperature pattern should be considered for thermoregulation strategies. Further investigation of the residual limb temperature with and without prosthesis, while considering muscles thickness and blood perfusion rate is warranted. Layman's Abstract The socket is a plastic hard-shell interface between the residual limb, the remaining part of the amputated limb, and a prosthesis. Heat buildup inside the prosthetic socket and perspiration of the residual limb are major discomforts in amputees when wearing a prosthesis. The majority of prior research measured residual limb skin temperature while the prosthesis was worn. However, less attention has been paid to skin temperature without prostheses. Skin temperature of eight adults with one-sided traumatic below-knee amputation was measured. Participants sat and removed their prostheses. Twelve anatomical sites were marked circumferentially in four columns and longitudinally in three rows over the residual limb and used for temperature recording using temperature sensors. The whole temperature of the residual limb was 27.73 (SD=0.83)°C. Skin temperature was higher at anterior columns compared to posterior columns. Similarly, the distal row of the residual limb had the lowest temperature compared to its middle and proximal rows. From a localized standpoint, the middle part at the anterior medial surface of the residual limb had the highest temperature, whereas the distal part at the anterior-medial surface had the lowest skin temperature. There was no noticeable relationship between the average of the residual limb skin temperature and participants’ demographic and clinical characteristics. Some strategies need to be developed to regulate and control heat dissipation over the residual limb's surface when amputees do not wear prostheses. Further temperature recording research by considering muscle thickness and arterial blood flow rate of the residual limb with and without prosthesis is suggested. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/35070/27313 How To Cite: Ghoseiri K, Allami M, Murphy J.R, Page P, Button D.C. Investigation of localized skin temperature distribution across the transtibial residual limb. Canadian Prosthetics & Orthotics Journal. 2021;Volume 4, Issue 1, No.2. https://doi.org/10.33137/cpoj.v4i1.35070 Corresponding Author: Duane C Button, PhDSchool of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada.E-mail: [email protected]: https://orcid.org/0000-0001-6402-8545

Pseudodiaptomus japonicus Kikuchi, 1928 (Copepoda, Pseudodiaptomidae), a brackish-water copepod formerly known as P. inopinus Burckhardt, 1913, on Sakhalin Island (Russian Far East)

We determined the taxonomic status of Pseudodiaptomus inopinus on Sakhalin using specimens from different localities, because it is currently known as a complex of species. The specimens examined appeared to belong to P. japonicus, based on the structure of the female genital operculum. However, a few females lacked spinules on the medial surface of the first exopodal segment of the female P5, which has been described as a character distinguishing P. japonicus from its two sibling species. The species is distributed in brackish waters from the very south to the very north of Sakhalin Island. The northernmost locality on Sakhalin is also the northernmost record of the species.

Contralateral interoptic approach to paraclinoid aneurysms: a patient-selection algorithm based on anatomical investigation and clinical validation

OBJECTIVEAneurysms that arise on the medial surface of the paraclinoid segment of the internal carotid artery (ICA) are surgically challenging. The contralateral interoptic trajectory, which uses the space between the optic nerves, can partially expose the medial surface of the paraclinoid ICA. In this study, the authors quantitatively measure the area of the medial ICA accessible through the interoptic triangle and propose a potential patient-selection algorithm that is based on preoperative measurements on angiographic imaging.METHODSThe contralateral interoptic trajectory was studied on 10 sides of 5 cadaveric heads, through which the medial paraclinoid ICA was identified. The falciform ligament medial to the contralateral optic canal was incised, the contralateral optic nerve was gently elevated, and the medial surface of the paraclinoid ICA was inspected via different viewing angles to obtain maximal exposure. The accessible area on the carotid artery was outlined. The distance from the distal dural ring (DDR) to the proximal and distal borders of this accessible area was measured. The superior and inferior borders were measured using the clockface method relative to a vertical line on the coronal plane. To validate these parameters, preoperative measurements and intraoperative findings were reviewed in 8 clinical cases.RESULTSIn the sagittal plane, the mean (SD) distances from the DDR to the proximal and distal ends of the accessible area on the paraclinoid ICA were 2.5 (1.52) mm and 8.4 (2.32) mm, respectively. In the coronal plane, the mean (SD) angles of the superior and inferior ends of the accessible area relative to a vertical line were 21.7° (14.84°) and 130.9° (12.75°), respectively. Six (75%) of 8 clinical cases were consistent with the proposed patient-selection algorithm.CONCLUSIONSThe contralateral interoptic approach is a feasible route to access aneurysms that arise from the medial paraclinoid ICA. An aneurysm can be safely clipped via the contralateral interoptic trajectory if 1) both proximal and distal borders of the aneurysm neck are 2.5–8.4 mm distal to the DDR, and 2) at least one border of the aneurysm neck on the coronal clockface is 21.7°–130.9° medial to the vertical line.

Restoration of the Age Elongated Auricular Lobe

Background The ears increase in all dimensions over the years (eg, length, helix diameter, lobe length), but the most obvious change is the elongation or ptosis of the lobe. Its correction should be considered a part of facial rejuvenation. Objectives The authors presented the surgical procedure they have been utilizing to correct elongated earlobes. Methods The authors described a simple and effective procedure consisting of the curved resection of the excess tissue of the lobe at its lower end and its reconstruction through the utilization of 2 triangular flaps of skin, taken from the lateral surface of the lobe, rotated backwards, and sutured to the medial surface, leaving a zigzag hidden scar. Results The authors have utilized this surgical procedure over the last 16 years to correct ptosis of the earlobe as well as some of its other alterations due to aging. The results obtained are presented as well as the classification that the authors have utilized to qualify their degree of ptosis. Conclusions This procedure has yielded excellent results, with imperceptible scars, and is therefore very pleasing to patients and surgeon alike. Level of Evidence: 4

Hydrocolloid Membrane Dressing in Shearing Injuries in the Distal Part of the Pelvic Limbs in Dogs

Background: Shearing wounds on the limbs of dogs usually affect the regions distally from the radiocarpal joint at the thoracic limb and from the tibiotarsal joint at the pelvic limb. The tissue coverage and re-epithelialization of the injured region are important factors that should be considered in the definitive surgical treatment. The hydrocolloid membrane promotes selective autolytic debridement and accelerates the formation of granulation tissue and epithelialization. The present study aims to describe the treatment with hydrocolloid membrane dressing of three cases of shearing wounds with concomitant orthopedic injuries in the pelvic limbs of dogs.Case: Three dogs with pelvic limb injuries after vehicular trauma were selected for treatment. Two patients had shearing lesions on the medial aspect of the pelvic limb with exposure of the tibia and fibula, the talus and the tibiotarsal joint, associated with bone loss on the medial surface of the limb and rupture of the medial collateral ligament of the tarsus. Another patient had a shearing wound on the dorsal surface of the distal region of the pelvic limb, with injury of the digital extensor tendons and bone exposure of the second and third metatarsals. Initially, the surgical debridement of the lesion was performed and during the first five days after trauma the wound was cleansed with chlorhexidine solution and topical application of crystallized sugar daily. In this initial period a dry adherent dressing was used on the lesions, without bandages for immobilization of the pelvic limb. In all dogs, the hydrocolloid membrane was applied from the sixth day after initial wound management. Immediately after the application of the hydrocolloid membrane, temporary immobilization of the affected pelvic limb with a padded Robert Jones bandage was performed. The first changes of the hydrocolloid membranes were performed after five days of their use. Subsequently, the membranes changes became more spaced and were performed within a period between 7 to 10 days. After wound repair, in one of the dogs with a shearing injury in the medial surface of the pelvic limb, the rupture of the medial collateral ligament was surgically treated with the use of anchor screws and nylon thread for the ligament reconstruction. The other dog presented with lesion in the medial surface of the pelvic limb and collateral ligament rupture was not submitted to late orthopedic surgical treatment. The latter was clinically managed and developed valgus deviation of the affected pelvic limb, but with functional use of the limb. The dog with a shearing lesion on the dorsal surface of the pelvic limb and injury to the extensor tendons was managed conservatively with use of orthosis and, after 45 days of initial trauma, the dog showed a functional lameness and absence of pain in the affected limb.Discussion: In all animals, the hydrocolloid membrane was applied on the wound from the sixth day after the initial lesion treatment. As the wound was healing the hydrocolloid dressing was changed in a more spaced period and this management allowed the proper tissue healing without complications. The wound treatment with dressing was aided by the application of temporary limb immobilization with padded bandage, until a late orthopedic procedure was performed or a final clinical resolution occurred. In general, the shearing wounds healed in a period ranging from 28 to 38 days. In conclusion, the use of the hydrocolloid membrane dressing associated with limb immobilization was an effective method for treatment of patients with shearing wounds, allowing proper healing of the affected tissues and good recovery of the limb function. The hydrocolloid membrane has the main benefits to allow the spaced changes of the dressings and the ability to stimulate the rapid healing of the wound.