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Forced elbow flexion and pressure during bicycling result in ulnar nerve traction and pressure exerted in Guyon's canal or the nerve's distal branches. The compression of the nerves causes a change in their stiffness related to edema and eventually gradual fibrosis. This study aimed to evaluate the elastography of terminal branches of the ulnar nerve in cyclists. Cross-sectional study. Thirty cyclists, 32 healthy individuals, and 32 volunteers with ulnar nerve entrapment neuropathies participated in the study. Each participant underwent a nerve examination of the cubital tunnel, Guyon's canal and the deep and superficial branches of the ulnar nerve using shear wave elastography. The cyclist group was tested before and after a 2-hour-long workout. Before cycling workouts, the ulnar nerve stiffness in the cubital tunnel and Guyon's canal remained below pathological estimates. Cycling workouts altered nerve stiffness in the cubital tunnel only. Notably, the stiffness of the ulnar terminal branches in cyclists was increased even before training. The mean deep branch stiffness was 50.85 ± 7.60 kPa versus 20.43 ± 5.95 kPa (p < 0.001) in the cyclist and healthy groups, respectively, and the mean superficial branch stiffness was 44 ± 12.45 kPa versus 24.55 ± 8.05 kPa (p < 0.001), respectively. Cycling contributed to a further shift in all observed values. These observations indicate the existence of persistent anatomical changes in the distal ulnar branches in resting cyclists that result in increased stiffness of these nerves. The severity of these changes remains, however, to be determined. These data show elastography values of the ulnar terminal branches in healthy individuals and cyclists where despite lack of clinical symptoms that they seem to be elevated twice above the healthy range. • Elastography of the ulnar nerve terminal branches. • A group of 30 cyclists compared to 32 healthy and 32 nerve entrapment volunteers. • Resting stiffness of the ulnar nerve distal branches had twice the increased value. • Cycling inducing a further increase in stiffness and confirms its irritating effect. • Presented range of normal and strongly increased values may be useful for clinicians. [ABSTRACT FROM AUTHOR]

Pedicled flap and free flap are two common types of superior gluteal artery (SGA) perforator flap (SGAP) used to cover lumbosacral soft tissue defects. In order to take advantage of the SGAP flap, all surgeons are required to have substantial knowledge of its cutaneous distribution of perforator. This study describes the anatomical characteristics of the perforators of SGA on Vietnamese adults; and locates the perforator of SGA on the gluteal region. We investigated the perforators origin and measured the length, diameter, course, and coordinates of each perforator on 32 Vietnamese adult cadavers at Department of Anatomy of Ho Chi Minh University of Medicine and Pharmacy, from Jan 2017 to June 2019. On average, SGA gives off 4-5 perforators, while none was found on the deep branch. The Average length of perforator from the skin to the dissecting point is short (5.5-7.5mm) compared to that of from skin to origin (4-9cm); diameter at origin is quite large (1mm). The chance of finding 3-5 perforators in the upper triangle is 75% and 87% on the right and left side, respectively. Also, the probability of finding a single perforator in the upper triangle is 100% based on the x-axis, most perforators are found in segment 2/5 to segment 3/5 with the center being the midpoint between two segments; based on the y-axis, most perforators are found in segment 1.5/5 to segment 3.5/5 with the center being the midpoint between the two. Thus, the probability of finding 3-5 perforators in the upper triangle is over 75% of the time, and the chance of finding a single perforator in the upper triangle is 100%. They are distributed from segment 2/5 to segment 3/5 on the x-axis and segment 1.5/5 to segment 3.5/5 on the y-axis. [ J Adv Biotechnol Exp Ther 2020; 3(2.000): 143-151]

Purpose The posterior interosseous nerve (PIN) is closely related to the proximal radius, and it is at risk when approaching the proximal forearm from the ventral and lateral side. This anatomic study analyzes the location of the PIN in relation to the proximal radius depending on forearm rotation by means of a novel investigation design. The purpose of this study is to define landmarks to locate the PIN intraoperatively in order to avoid neurological complications. Methods We dissected six upper extremities of fresh-frozen cadaveric specimens. The mean donor age at the time of death was 81.2 years. The PIN was dissected and marked on its course along the proximal forearm with a 0.3-mm flexible radiopaque thread. Three-dimensional (3D) X-ray scans were performed, and the location of the nerve was analyzed in neutral rotation, supination, and pronation. Results In the coronal view, the PIN crosses the radial neck/shaft at a mean of 33.4 (±5.9) mm below the radial head surface (RHS) in pronation and 16.9 (±5.0) mm in supination. It crosses 4.9 (±2.2) mm distal of the most prominent point of the radial tuberosity (RT) in pronation and 9.6 (±5.2) mm proximal in supination. In the sagittal view, the PIN crosses the proximal radius 61.8 (±2.9) mm below the RHS in pronation and 41.1 (±3.6) mm in supination. The nerve crosses 29.2 (±6.2) mm distal of the RT in pronation and 11.0 (±2.8) mm in supination. Conclusion With this novel design, the RT could be defined as a useful landmark for intraoperative orientation. On a ventral approach, the PIN courses 10 mm proximal of it in supination and 5 mm distal of it in pronation. Laterally, pronation increases the distance of the PIN to the RT to approximately 3 cm. [ABSTRACT FROM AUTHOR]

Background The polyadenylation of RNA is critical for gene functioning, but the conserved sequence motifs (often called signal or signature motifs), motif locations and abundances, and base composition patterns around mRNA polyadenylation [poly(A)] sites are still uncharacterized in most species. The evolutionary tendency for poly(A) site selection is still largely unknown. Results We analyzed the poly(A) site regions of 31 species or phyla. Different groups of species showed different poly(A) signal motifs: UUACUU at the poly(A) site in the parasite Trypanosoma cruzi; UGUAAC (approximately 13 bases upstream of the site) in the alga Chlamydomonas reinhardtii; UGUUUG (or UGUUUGUU) at mainly the fourth base downstream of the poly(A) site in the parasite Blastocystis hominis; and AAUAAA at approximately 16 bases and approximately 19 bases upstream of the poly(A) site in animals and plants, respectively. Polyadenylation signal motifs are usually several hundred times more abundant around poly(A) sites than in whole genomes. These predominant motifs usually had very specific locations, whether upstream of, at, or downstream of poly(A) sites, depending on the species or phylum. The poly(A) site was usually an adenosine (A) in all analyzed species except for B. hominis, and there was weak A predominance in C. reinhardtii. Fungi, animals, plants, and the protist Phytophthora infestans shared a general base abundance pattern (or base composition pattern) of "U-rich—A-rich—U-rich—Poly(A) site—U-rich regions", or U-A-U-A-U for short, with some variation for each kingdom or subkingdom. Conclusion This study identified the poly(A) signal motifs, motif locations, and base composition patterns around mRNA poly(A) sites in protists, fungi, plants, and animals and provided insight into poly(A) site evolution. [ABSTRACT FROM AUTHOR]

The deep (motor) branch of the ulnar nerve is not frequently seen during surgery, but is vulnerable to penetrating injury and may be injured during surgery. Its anatomy is poorly described and its three-dimensional configuration is poorly appreciated. In this study, dissections of ten cadaveric specimens have been performed to demonstrate the branching pattern of the nerve and its skeletal relations have been clarified by superimposing images on radiographs. The deep branch passes downwards (anatomical posterior) through a hypothenar fibro-muscular tunnel and courses radially on the surface of the interossei. It has four major divisions that are consistent and readily identifiable. Twenty branches were documented supplying hypothenar muscles, medial two lumbricals, interossei, adductor pollicis, all the carpometacarpal and the ring and little metacarpophalangeal joints, and opponens pollicis in 40% and flexor pollicis brevis in 20% of subjects. [ABSTRACT FROM AUTHOR]

Reinnervation of the intrinsic hand muscles after proximal ulnar nerve repair is often unsatisfactory. Promising results have nevertheless been reported recently for supercharged end-to-side anterior interosseous to deep branch of the ulnar nerve (DBUN) transfer. The aim of this study was to determine whether the DBUN can be reliably identified without retrograde intraneural dissection from Guyon's canal. Twenty cadaveric wrists were dissected. In a first stage, nerve transfer was performed through a limited 4 cm incision without releasing Guyon's canal. In a second stage, correct identification of the DBUN was assessed by retrograde intraneural dissection from its point of exit from Guyon's canal. The DBUN was correctly identified in 18 of the 20 wrists (90%). Although anatomical landmarks provide valuable clues, identifying the DBUN by neurolysis is technically challenging. All the elements required for nerve transfer can be exposed through a 4 cm incision, but the DBUN was nevertheless incorrectly identified in 10% of cases. Guyon canal release seems advisable to guarantee correct DBUN identification., (Copyright © 2021 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

In order to achieve a satisfactory functional and aesthetic result a thin skin flap is often required in surgical reconstruction of various body regions. Perforator flaps based on either the superficial or deep branch of the superficial circumflex iliac artery (SCIA) have been used for this purpose mainly in the Asian population. Recently the superficial plane has been established as a new way of elevating the flap. Anatomical studies and details of this new flap are lacking. Wide areas were harvested subfascially from the groin of Thiel-fixated cadavers. Both deep and superficial branches of the superficial circumflex iliac artery were carefully dissected and individually injected with μAngiofil. After CT-imaging the flaps were raised on the superficial plane, perforators were marked and the flaps subsequently rescanned. High-resolution images of regions of interest were taken using micro-CT. A total of 21 flaps were harvested and analyzed. Both the deep and superficial branch provided more than three perforators per branch, however, the deep branch based flap was significantly larger (202 vs. 112 cm2, p < 0.01) and had a longer pedicle (9.1 vs. 6.6 cm, p < 0.01). Raising the flap in the superficial plane reliably reduces bulk and increases homogeneity. The SCIP flap appears to have a reliable vascular blood supply. The SCIA and its main branches and perforators have a consistent vascular pattern. The deep branch of the SCIA has the anatomic potential to be the preferred pedicle in case larger flaps with longer pedicles are necessary. [ABSTRACT FROM AUTHOR]

The femoral head receives blood supply mainly from the deep branch of the medial femoral circumflex artery (MFCA). In previous studies we have performed anatomical dissections of 16 specimens and subsequently visualised the arteries supplying the femoral head in 55 healthy individuals. In this further radiological study we compared the arterial supply of the femoral head in 35 patients (34 men and one woman, mean age 37.1 years (16 to 64)) with a fracture/dislocation of the hip with a historical control group of 55 hips. Using CT angiography, we identified the three main arteries supplying the femoral head: the deep branch and the postero-inferior nutrient artery both arising from the MFCA, and the piriformis branch of the inferior gluteal artery. It was possible to visualise changes in blood flow after fracture/dislocation. Our results suggest that blood flow is present after reduction of the dislocated hip. The deep branch of the MFCA was patent and contrast-enhanced in 32 patients, and the diameter of this branch was significantly larger in the fracture/dislocation group than in the control group (p = 0.022). In a subgroup of ten patients with avascular necrosis (AVN) of the femoral head, we found a contrast-enhanced deep branch of the MFCA in eight hips. Two patients with no blood flow in any of the three main arteries supplying the femoral head developed AVN.