Impact of Intermolecular Non-Covalent Interactions in a CuI 8 PdII 1 Discrete Assembly: Conformers' Geometries and Stimuli-Sensitive Luminescence Properties.

A new highly solid-state luminescent phase of a previously reported weakly luminescent CuI 8 PdII 1 dicationic assembly is reported revealing the high geometrical versatility of this moiety that importantly alters its luminescent properties. This very minor new species Bc is based on a different conformer scaffold than the one encountered in the previously reported Bo form and, essentially differs from Bo by displaying shorter CuI -CuI intermetallic distances. DFT calculations allow concluding that the predominance in the solid-state of the weakly luminescent and less stable Bo phase is due to the extra stability induced by a larger number of intermolecular non-covalent π-CH interactions in its crystalline packing and not by the intrinsic stability of the CuI 8 PdII 1 dicationic moiety. Calculations also revealed that a more stable conformation Bcalc is expected in vacuum, which bears a different distribution of CuI -CuI intermetallic distances than the dications in Bo and Bc phases. Taking into account that the geometrical alterations are associated to drastic changes of luminescence properties, this confer to the CuI 8 PdII 1 assembly high potentiality as stimuli-sensitive luminescent materials. Indeed, by applying mechanical or thermal stress to samples of Bo phase, new phases Bg and Bm , respectively, were obtained. Alterations of the solid-state photophysical properties of these new species compared to those recorded for Bo are reported together with a combined experimental and computed study of the structures/properties relationships observed in these phases.

Anatomy of the axillary arch: from its incidence in human to an embryologic and a phylogenetic explanation of its origins.

INTRODUCTION: Typically, the axillary arch is defined as a fleshy slip running from latissimus dorsi to the anterior aspect of the humerus. Phylogeny seems to give the most relevant and plausible explanation of this anatomical variant as a remnant of the panniculus carnosus. However, authors are not unanimous about its origin. We report herein the incidence of axillary arch in a series of 40 human female dissections and present an embryologic and a comparative study in three domestic mammals. MATERIALS AND METHODS: Forty formalin-preserved Caucasian human female cadavers, one rat (Rattus norvegicus), one rabbit (Oryctolagus cuniculus) and one pig (Sus scrofa domesticus) cadavers were dissected bilaterally. A comparative, analytical and a descriptive studies of serial human embryological sections were carried out. RESULTS: We found an incidence of axillary arch of 2.5% (n = 1 subject of 40) in Humans. We found a panniculus carnosus inserted on the anterior aspect of the humerus only in the rat and the rabbit but not in the pig. The development of the latissimus dorsi takes place between Carnegie stage 16-23, but the embryological study failed to explain the genesis of the axillary arch variation. However, comparative anatomy argues in favour of a panniculus carnosus origin of the axillary arch. CONCLUSIONS: With an incidence of 2.5% of cases, the axillary arch is a relatively frequent variant that should be known by clinician and especially surgeons. Moreover, while embryology seems to fail to explain the genesis of this variation, comparative study gives additional arguments which suggest a possible origin from the panniculus carnosus.

On the reliability of acquiring molecular junction parameters by Lorentzian fitting of I/V curves.

Fitting the I/V curves of molecular junctions by simple analytical models is often done to extract relevant molecular parameters such as energy level alignment or interfacial electronic coupling to build up useful property-relationships. However, such models can suffer from severe limitations and hence provide unreliable molecular parameters. This is illustrated here by extracting key molecular parameters by fitting computed voltage-dependent transmission spectra and by comparing them to the values obtained by fitting the calculated I/V curves with a typical Lorentzian model used in the literature. Doing so, we observe a large discrepancy between the two sets of values which warns us about the risks of using simple fitting expressions. Interestingly, we demonstrate that the quality of the fit can be improved by imposing the low bias conductance and Seebeck coefficient of the junction to be recovered in the fitting procedure.

Three-Dimensional Modelization of the Female Human Inferior Hypogastric Plexus: Implications for Nerve-Sparing Radical Hysterectomy.

BACKGROUND/AIMS: This study aims to describe the autonomic nervous network of the female pelvis with a 3D model and to provide a safe plane of dissection during radical hysterectomy for cervical cancer. METHODS: Pelvises of 3 human female fetuses were studied by using the computer-assisted anatomic dissection. RESULTS: The superior hypogastric plexus (SHP) was located at the level of the aortic bifurcation in front of the sacral promontory and divided inferiorly and laterally into 2 hypogastric nerves (HN). HN ran postero-medially to the ureter and in the lateral part of the uterosacral ligament until the superior angle of the inferior hypogastric plexus (IHP). IHP extended from the anterolateral face of the rectum, laterally to the cervix and attempted to the base of the bladder. Vesical efferences merged from the crossing point of the ureter and the uterine artery and ran through the posterior layer of the vesico-uterine ligament. CONCLUSIONS: The SHP could be injured during paraaortic lymphadenectomy. Following the ureter and resecting the medial fibrous part of the uterosacral ligament may spare the HN. No dissection should be performed under the crossing point of the ureter and the uterine artery.

Anatomical variations of the subscapular pedicle and its terminal branches: an anatomical study and a reappraisal in the light of current surgical approaches.

PURPOSE: While anatomical variations of the subscapular vessels are frequently encountered during axillary dissection, little is found in the literature. The aim of this cadaveric study was to define arterial and venous anatomical variations and frequencies of the subscapular vascular pedicle and its terminal/afferent vessels in women. METHODS: We performed 80 dissections of the axillary region on forty female formalin-embalmed cadavers. Each anatomical arrangement was photographed and recorded on a scheme before analysis. RESULTS: We propose a new classification of the subscapular pedicle variations. We observed three types of subscapular arterial variation. The type Ia was the most frequent arrangement (71% of our dissections), the type Ib was observed in 11% and the type II in 18% of cases. We observed four types of subscapular venous variation. The type Ia was observed in 63% of cases, the type Ib in 14%, the type II in 14% and the type III in 10% of cases. CONCLUSIONS: This knowledge of the anatomical variation arrangement and frequencies of the subscapular vascular pedicle will assist the surgeon when dissecting the axillary region for malignant or reconstructive procedures.

Vaginal mesh repair SYSTEMS for pelvic organ prolapse: Anatomical study comparing transobturator/trangluteal versus single incision techniques.

INTRODUCTION: The present study aim to compare the anatomic landmarks of two pelvic floor repair systems, in order to identify the potential neurovascular lesions related to different mesh fixation techniques. METHODS: Abdominal and perineal dissections of 10 fresh cadavers after prolapse surgery using transobturator/transgluteal versus single incision techniques. Neuro-vascular structures of obturator region and perineum were isolated. Distances between needles and anatomical structures were measured. RESULTS: During transobturator anterior repair, the superficial cannula passed 2.5 ± 0.6 cm medially to the obturator canal. The distance of superficial arm to the anterior obturator vessels was 2.2 ± 0.4 cm. The distance of deep cannula to the posterior obturator vessels branches was 1.3 ± 0.5 cm. In two of these cases we observed a lesion of posterior obturator vessels. During single incision repair the distance between the obturator canal and the superficial arms was 2.3 ± 0.7. The mean distances of superficial arms to the anterior and posterior obturator vessels were, respectively, 2.3 ± 0.5 cm and 3.2 ± 0.7 cm. During transgluteal posterior repair the distance between the cannula guide and the ischial spine was 1.7 ± 0.5 cm while it measured 2.3 ± 0.4 cm when single incision posterior device was placed. CONCLUSIONS: Anterior transobturator system presents an increased risk of posterior obturator vessels branches injury. During posterior transgluteal repair the distance of the ischio-anal fossa to sacrospinous ligament represents a way that could rule against the correct needle positioning with increased risk of pudendal lesions. Single incision approach offers an easier access to the sacrospinous ligament with lower risk of pudendal lesions.

Comparative anatomy on 3-D MRI of the urogenital sinus and the periurethral area before and during the second stage of labor during childbirth.

PURPOSE OF THE STUDY: To describe the observable MRI changes in the urogenital sinus during the second stage of labor and delivery by comparing the changes in the positions of the anatomical structures of the maternal perineum using MRI-based vector 3-D models. MATERIALS AND METHODS: Seven pregnant women underwent 3-D MRI sequences using a Philips 1 T Panorama open MRI during the pre-labor period and during the second stage of labor. A 3-D vector reconstruction platform (BABYPROGRESS, France) enabled the transformation of volumes of 2-D images into finite element meshes. The polygonal meshes labeled with the principal components of the urogenital sinus were used as part of a biomechanical study of the pressure exerted on the perineum during fetal descent. RESULTS: The expansion of the urogenital sinus was observed in all patients. Qualitative stretching was observed toward the rear and bottom of the iliococcygeus, pubococcygeus, puborectalis and obturator internus muscles. Significant length differences were measured along the iliococcygeus and pubococcygeus muscles but not along the tendinous arch of the levator ani or the puborectalis muscle. The inversion of the levator ani muscle curvature was accompanied by the transmission of pressure generated during fetal descent to the pubic muscle insertions and the descent of the tendinous arch of the levator ani. CONCLUSION: Mechanical pressures responsible for the tensioning of the constituent muscles of the urogenital sinus were qualitatively identified during the second stage of labor. MRI-based vector 3-D models allow the quantitative assessment of levator ani muscle stretching during labor, but 2-D MRI is not sufficient for describing perineal expansion. Vector 3-D models from larger scale studies have the potential to aid in the calibration of a realistic simulation based on the consideration of the reaction of each muscular element. These models offer perspectives to enhance our knowledge regarding perineal expansion during childbirth as a risk factor for postpartum perineal defects.

New insights into the morphogenesis of the gubernaculum testis and the inguinal canal.

There is no consensus about the role of the gubernaculum testis (GT). Nineteen human embryos (Carnegie stages 15-23), 36 fetuses (9 weeks to term), and eight neonates were examined. All the embryos and 25 fetuses (from weeks 9-16) were processed for paraffin wax histology and serially sectioned at 10 µm thickness. The remaining 11 fetuses and the eight neonates were fresh specimens that were dissected under a surgical microscope. The GT appeared during the embryonic period (stages 17-23) with a horseshoe-shaped mesenchyme condensation of the superior concavity, which was observed in four different topographical regions sequentially through development. The GT was not attached at either of its ends in any of the specimens, not to the gonad or in the scrotal sac. The inguinal canal differentiates around the inguinal portion of the GT during the late embryonic period. After stage 21, the GT appears enveloped by an evagination of the peritoneal cavity. It has few striate muscular fibers and vessels. Although the GT does not appear to have the role traditionally attributed to it, it is still an essential structure and indirectly facilitates the descent of the testes. It contributes to the formation of the inguinal canal and then forges the pathway that the testes will subsequently take through the inguinal canal as they migrate from the abdominal cavity into the scrotal sac. Clin. Anat. 30:599-607, 2017. © 2017 Wiley Periodicals, Inc.

Anatomical insights into sacrocolpopexy for multicompartment pelvic organ prolapse.

AIMS: Pelvic organ prolapse occurs in 50% of parous women. Laparoscopic sacrocolpopexy (LSCP) is a common surgical procedure for restoring pelvic anatomy and function. The aim of this study is to evaluate surgical anatomy and anatomical modifications induced by standardized LSCP. METHODS: Ten fresh female cadavers underwent LSCP, six subsequently underwent standard anatomical dissection, and four had sagittal anatomical dissection. Four cadavers were used as control subjects; two of them underwent standard anatomical dissection, and two had sagittal anatomical dissection. RESULTS: Vesicovaginal space dissection resulted in an arrow-shaped space limited by the trigone and vesical branches of the uterine artery. Rectovaginal space dissection resulted in an inverted V-shaped space marked by the utero-sacral and rectovaginal ligaments, the cranial end of the perineal body and the levator ani muscle. Exposing the longitudinal vertebral ligament through a peritoneal and presacral fascia incision along the medial border of the right common iliac artery allowed the identification and the preservation of the right hypogastric nerve. The anterior mesh stretched across the proximal half of the anterior vaginal wall, and the cervix towards the sacral promontory provided excellent cervix suspension and anterior-vaginal wall support with a concomitant stretch of the pubocervical fascia. The median angle formed by the axis of the infra-levatorial vagina with the axis of the supra-levatorial vagina changed from 142° to 171° and determined the linearization-ventralization of the vaginal canal. CONCLUSIONS: LSCP can be performed in a nerve-sparing, standardized fashion, providing excellent apical suspension and anterior vaginal wall support. Neurourol. Urodynam. 35:813-818, 2016. © 2015 Wiley Periodicals, Inc.

[Functional anatomy of the pelvic floor]. / Anatomie fonctionnelle du plancher pelvien.

The pelvic floor is the support of the pelvic viscera. The levator ani muscle (LA) with its two bundles (pubo- and iliococcygeus) is the major component of this pelvic floor. LA is formed essentially by type I fibers (slow twitch, with high oxidative capability and presence of slow myosin) as in postural muscles. The aerobic metabolism makes LA fragile to excentric contraction and to mitochondrial dysfunction. The innervation of the pelvic floor comes from the 2nd, 3rd, 4th anterior sacral roots; denervation affects pelvic dynamism. Perineum includes the musculofascial structures under the LA: ventrally the striated sphincter of urethra and the ischiocavernosus and bulbospongiosus, caudally the fatty tissue filling the ischioanal fossa. Pelvic fascia covers the muscles ; it presents reinforcements : the uterosacral and cardinal ligaments, the arcus tendineus fascia pelvis (ATFP) and the arcus tendineus levator ani (ATLA). The pelvis statics is supported by the combined action of all this anatomical structures anteriorly forming the perineal "hammock," medially the uterosacral and cardinal ligaments, posteriorly the rectovaginal fascia and the perineal body. The angles formed by the pelvic viscera with their evacuation ducts participate to the pelvic statics. During the pelvic dynamics the modification of these angles expresses the action of the musculofascial structures.

In vivo visualization of the levator ani muscle subdivisions using MR fiber tractography with diffusion tensor imaging.

Understanding the levator ani complex architecture is of major clinical relevance. The aim of this study was to determine the feasibility of magnetic resonance (MR) fiber tractography with diffusion tensor imaging (DTI) as a tool for the three-dimensional (3D) representation of normal subdivisions of the levator ani. Ten young nulliparous female volunteers underwent DTI at 1.5 T MR imaging. Diffusion-weighted axial sequence of the pelvic floor was performed with additional T2-weighted multiplanar sequences for anatomical reference. Fiber tractography for visualization of each Terminologia Anatomica-listed major levator ani subdivision was performed. Numeric muscular fibers extracted after tractography were judged as accurate when localized within the boundaries of the muscle, and inaccurate when projecting out of the boundaries of the muscle. From the fiber tracking of each subdivision the number of numeric fibers (inaccurate and accurate) and a score (from 3 to 0) of the adequacy of the 3D representation were calculated. All but two volunteers completed the protocol. The mean number of accurate fibers was 17 ± 2 for the pubovisceralis, 14 ± 6 for the puborectalis and 1 ± 1 for the iliococcygeus. The quality of the 3D representation was judged as good (score = 2) for the pubovisceralis and puborectalis, and inaccurate (score = 0) for the iliococcygeus. Our study is the first step to a 3D visualization of the three major levator ani subdivisions, which could help to better understand their in vivo functional anatomy.

A 970 Hounsfield units (HU) threshold of kidney stone density on non-contrast computed tomography (NCCT) improves patients' selection for extracorporeal shockwave lithotripsy (ESWL): evidence from a prospective study.

UNLABELLED: What's known on the subject? and What does the study add? Stone density on non-contrast computed tomography (NCCT) is reported to be a prognosis factor for extracorporeal shockwave lithotripsy (ESWL). In this prospective study, we determined that a 970 HU threshold of stone density is a very specific and sensitive threshold beyond which the likelihood to be rendered stone free is poor. Thus, NCCT evaluation of stone density before ESWL may useful to identify which patients should be offered alternative treatment to optimise their outcome. OBJECTIVE: • To evaluate the usefulness of measuring urinary calculi attenuation values by non-contrast computed tomography (NCCT) for predicting the outcome of treatment by extracorporeal shockwave lithotripsy (ESWL). PATIENTS AND METHODS: • We prospectively evaluated 50 patients with urinary calculi of 5-22 mm undergoing ESWL. • All patients had NCCT at 120 kV and 100 mA on a spiral CT scanner. Patient age, sex, body mass index, stone laterality, stone size, stone attenuation values (Hounsfield units [HU]), stone location, and presence of JJ stent were studied as potential predictors. • The outcome was evaluated 4 weeks after the ESWL session by NCCT. • ESWL success was defined as patients being stone-free (SF) or with remaining stone fragments of <4 mm, which were considered as clinically insignificant residual fragments (CIRF). RESULTS: • Our survey concluded that 26 patients (52%) were SF, 12 (24%) had CIRF and 12 (24%) had residual fragment on NCCT after a one ESWL treatment. • Stones of patients who became SF or had CIRF had a lower density compared with stones in patients with residual fragments [mean (sd) 715 (260) vs 1196 (171) HU, P < 0.001]. • The Youden Index showed that a stone density of 970 HU represented the most sensitive (100%) and specific (81%) point on the receiver-operating characteristic curve. • The stone-free rate for stones of <970 HU was 96% vs 38% for stones of ≥ 970 HU (P < 0.001). A linear relationship between the calculus density and the success rate of ESWL was identified. CONCLUSION: • The use of NCCT to determine the attenuation values of urinary calculi before ESWL helps to predict treatment outcome, and, consequently, could be helpful in planning alternative treatment for patients with a likelihood of a poor outcome from ESWL.

Anterior sacrospinous ligament fixation associated with paravaginal repair using the Pinnacle device: an anatomical study.

INTRODUCTION AND HYPOTHESIS: The objective of this paper is to study the reproducibility and anatomical risks of anterior sacrospinous ligament (SSL) fixation associated with paravaginal repair using the Pinnacle device (Boston Scientific). METHODS: Simplified bilateral anterior SSL fixation associated with paravaginal fixation through the arcus tendineus fascia pelvis (ATFP) was performed on five fresh cadavers using the Pinnacle device. Cadaver dissection was then performed by open pelvic surgery. RESULTS: Eight SSL and ten ATFP were available for analysis. SSL fixations were optimal in four cases, too superficial in three cases, and too high in one case. Mean distance between SSL fixation and ischial spine was 18.6 mm (range 10 to 30 mm). Mean distance between SSL fixation and pudendal nerve was 6.5 mm (range 0 to 15 mm). ATFP fixations were optimal in five cases, good in four cases, and too superficial in one case. In one case (10%), the middle arm of the prosthesis was in contact with the ureter and traction on that arm resulted in ureteral kinking. CONCLUSIONS: Anterior SSL fixation associated with paravaginal repair using the Pinnacle™ device was not reproducible every time in this cadaver study. These results confirm the need for specific training before starting anterior SSL fixations.

Pelvic organ prolapse transvaginal repair by the Prolift system: evaluation of efficacy and complications after a 4.5 years follow up.

OBJECTIVES: The Prolift system is a polypropylene device designed for pelvic organ prolapse repair by a transvaginal approach. Numerous studies have reported on short-term outcomes of this procedure, but long-term studies are lacking. METHODS: A retrospective study of patients who underwent pelvic organ prolapse repair by Prolift between September 2005 and September 2008 was carried out in two tertiary reference centers by two experienced surgeons. Preoperative and postoperative follow up was based on medical records of baseline and follow-up visits with complete clinical examination, including Pelvic Organ Prolapse Quantification stage. At last follow up, the Pelvic Floor Distress Inventory-20 questionnaire was assessed by telephone interview. Cure was defined as an anatomical success at last follow up, being a Pelvic Organ Prolapse Quantification stage ≤ 1 without further surgical intervention in any compartment. RESULTS: A total of 75 patients were included in this analysis with a mean follow up of 53.7 ± 8.8 months (range 36-72 months). Patients were treated with two-arm Prolift posterior, four-arm Prolift anterior and six-arm Prolift total in three (4%), 51 (69%) and 21 (27%) cases, respectively. At last follow up, 64 (85.3%) patients were cured, with no prolapse recurrence. Mesh exposure occurred in four (5.3%) patients. The Pelvic Floor Distress Inventory-20 symptom score was low at last follow up (median 8, range 3-18), in accordance with objective cure data. CONCLUSIONS: The Prolift system is safe and efficacious for pelvic organ prolapse repair by transvaginal approach after a 4.5-year follow up.

Computer-assisted anatomic dissection (CAAD): evolution, methodology and application in intra-pelvic innervation study.

OBJECTIVE: Classic anatomical methods have limitations in micro determination of nerve fibre location. Furthermore, the precise detection of the nerve fibres nature is not possible by means of dissection. The combination of immunohistochemistry and three-dimensional reconstruction could be used to resolve these limitations of morphological sciences. Our aim is to describe the evolution of computer-assisted anatomic dissection (CAAD), which is an original method applied to study the distribution of intra-pelvic nerves in anatomic research. MATERIALS AND METHODS: Serial transverse sectioning of the pelvic region in rabbit, human fetus, infant and adult cadaver was performed. Sections were immuno-histochemically stained and digitized with a high optical resolution scanner. Photoshop 7 software was used in regrouping of the adult cadaver sections then a tri-dimensional reconstruction was achieved using WinSurf software. RESULTS: The 3D reconstruction of the immuno-histochemically stained histologic sections of the pelvis allowed for precise structural identification of the prostate and its innervations (in fetus, infant and adult). In addition, we reconstructed the entire intra-pelvic organs with accurate demonstration of the location of both adrenergic and cholinergic pathways. Moreover, we performed a virtual dissection of each of the pelvic structures with description of the exact location of the inferior hypogastric plexus, as well as the nature and the distribution of its fibres. CONCLUSION: The CAAD is an original method in anatomic research, which illustrates the fact that descriptive anatomy is still a dynamic science. This method allows for a 3D presentation of the intra-organic innervation, the nature of the nerve fibres, and the distribution of receptors and their neurotransmitters. This technique improves the understanding of the complex anatomic regions such as the pelvis from both surgical and educational point of view.

Electronic transport through single-molecule oligophenyl-diethynyl junctions with direct gold-carbon bonds formed at low temperature.

We report on the first systematic transport study of alkynyl-ended oligophenyl-diethynyl (OPA) single-molecule junctions with direct Au-C anchoring scheme at low temperature using the mechanically controlled break junction technique. Through quantitative statistical analysis of opening traces, conductance histograms and density functional theory studies, we identified different types of junctions, classified by their conductance and stretching behavior, for OPA molecules between Au electrodes with two to four phenyl rings. We performed inelastic electron tunneling spectroscopy and observed the excitation of Au-C vibrational modes confirming the existence of Au-C bonds at low temperature and compared the stability of molecule junctions upon mechanical stretching. Our findings reveal the huge potential for future functional molecule transport studies at low temperature using alkynyl endgroups.

Vagina, abdominal skin, and aponeurosis: do they have similar biomechanical properties?

INTRODUCTION AND HYPOTHESIS: despite minimal fundamental works, there is an increasing use of meshes in urogynecology. The concept is mainly based on experiences with abdominal wall surgery. We aimed to compare the biomechanical properties of vaginal tissue, abdominal aponeurosis, and skin. METHODS: samples from 11 fresh women cadavers without prolapse were collected. Uniaxial tension tests were performed and stress-strain curves were obtained. RESULTS: biomechanical properties of the vagina, aponeurosis, and skin differed significantly. The aponeurosis was much more rigid and less extendible than the vagina and skin. Vaginal tissue was less rigid but more extendible than skin. There was no difference between the vagina and skin at low strains (p = 0.341), but a highly significant difference at large strains (p = 0.005). CONCLUSIONS: skin and aponeurosis are not suited to predict vaginal tissue biomechanics. We should be cautious when transferring experiences from abdominal wall surgery to vaginal reconstructive surgery.

Is there any evidence of superiority between retropubic, laparoscopic or robot-assisted radical prostatectomy?

PURPOSE: To compare the perioperative, short-term and long-term postoperative results of radical retropubic prostatectomy (RRP), laparoscopic radical prostatectomy (LRP) and robotic assisted laparoscopic prostatectomy (RALP) in the most recent studies evaluable. MATERIALS AND METHODS: Using PubMed we have undertaken a search based on references from major and recent articles with considerable sample sizes. RESULTS: The operative blood loss and the risk of transfusion were lower in the laparoscopic and robotic-assisted approaches. The surgical duration was shorter in the open and robotic group. Regarding the positive margins, continence and potency no substantial differences between the RRP, LRP, and RALP were found. CONCLUSIONS: Our results suggest that no one surgical approach is superior in terms of functional and early oncologic outcomes. Potential advantages of any surgical approach have to be confirmed through longer-term follow-up and adequately designed clinical studies.

The ankle retinacula: morphological evidence of the proprioceptive role of the fascial system.

STUDY DESIGN: Research report. OBJECTIVES: To evaluate the anatomical characteristics of the ankle retinacula and their relationship with the fasciae and muscles in healthy subjects and in patients with ankle sprain outcomes. BACKGROUND: The role of the retinacula in proprioception has begun to emerge, but without clear anatomical bases or descriptions of their possible damage in patients with ankle sprain outcomes. METHODS: Dissection, histological and immunohistochemical analysis of 27 legs. An in vivo radiological study by MRI was also performed on 7 healthy volunteers, 17 patients with outcomes of ankle sprain, and 3 amputated legs. RESULTS: The retinacula are thickenings of the deep fascia presenting bone or muscular connections. They are formed of 2-3 layers of parallel collagen fibre bundles, densely packaged with a little loose connective tissue, without elastic fibres but many nervous fibres and corpuscles. By MRI, the retinacula appeared as low-signal-intensity bands with a mean thickness of 1 mm. In patients with outcomes of ankle sprain, MR findings were abnormal retinacula thickness, signal intensity, and full-thickness gap. DISCUSSION: The retinacula are not static structures for joint stabilisation, like the ligaments, but a specialisation of the fascia for local spatial proprioception of the movements of foot and ankle. Their anatomical variations and accessory bundles may be viewed as morphological evidence of the integrative role of the fascial system in peripheral control of articular motility.

Traditional versus three-dimensional teaching of peritoneal embryogenesis: a comparative prospective study.

INTRODUCTION: Anatomy teaching is newly boosted by the development of interactive three-dimensional (3D) teaching techniques. Nevertheless, their superiority as teaching aids has never been demonstrated. The aim of this study was to compare 3D and traditional chalk teaching efficiency in terms of student memorization concerning peritoneal embryogenesis. MATERIALS AND METHODS: 165 students from the Faculties of Medicine of Sfax (Tunisia) (n = 81) and of Paris-Descartes (France) (n = 84) were taught peritoneal embryogenesis either via a 3D technique (interactive DVD ROM) (3D group, n = 85) or via the traditional chalk technique (CL group, n = 80). Both groups were subjected to an evaluation test including 34 questions distributed in six chapters at the end of the course. RESULTS: The overall rate of correct answers was higher in the 3D group (65.12 +/- 14.88 vs. 49.33 +/- 16.17%, p < 0.001). It was the same for five of the six chapters of questions excluding the chapter concerning the clinical implications (p = 0.06). There was no significant difference between 3D and CL groups regarding the 20 questions focusing on static phenomena (64.52 +/- 27.10 vs. 58.87 +/- 23.67%, p = 0.24), but the rate of correct answers was higher in the 3D group for the 14 questions focusing on dynamic phenomena (65.96 +/- 20.97 vs. 28.17 +/- 24.40%, p < 0.001). CONCLUSION: The 3D technique is significantly more efficient than the traditional chalk technique for the teaching of peritoneal embryogenesis in terms of short-term memorization and particularly for the assimilation of dynamic phenomena. Medium-term and long-term studies are needed to demonstrate that this benefit has a long-lasting impact.