Clinico-anatomical Study Research Articles

Evaluation of human temporal bone for loacting favourable site to place longer implant for implant retained auricular prosthesis –a clinicoanatomic study

Aim: To find sites in human temporal bone for placing longer implant Materials & Methods: Dry human skull were procured from the anatomy department. External acoustic meatus(EAM) was taken as reference point from that point five arcs of radius15mm, 20mm,25mm,30mm,35 mm were drawn over the temporal bone. The temporal bone removed from the skull and the bone is removed from the outer most point towards the EAM. The thickness of the bone at 1oClock and 4o Clock position and 8oClock and 11o Clock position over the left and right side of the temporal measured using digital Vernier calliper. The temporal bone is thicker at the 3oClock on the left and 9oClock on the right side. The thickness at the new position also measured. Result: The mean bone thickness at 15mm, 20mm, 25mm ranges from 3.92 to 12.08mm. The mean bone Thickness at the 3oclock and 9 o clock position at the distance of 20mm from EAM ranges from 8.21 to 8.50mm.The Statistical significance within the group were analysed using paired t test and found to be statistical significant at P value less than. 05. Conclusion: The external surface of temporal bone at the 3oClock on the left and 9oClock on the right side denser and thicker. The bone availability is also more favours for placing longer implant.

Landmarks for facial nerve identification in parotid surgery: A clinico-anatomical study

Background: Preserving the integrity of the facial nerve during parotid surgery depends on its exposure, and this requires a detailed knowledge of its anatomy by the operating surgeon. For easy identification of the facial nerve, a number of landmarks have been described. Objective: The purpose of this study was to review the distances of the facial nerve trunk (FNT) from four commonly used landmarks, namely the tragal pointer, tympanomastoid suture, posterior belly of the digastric muscle (PBDM), and junction of the bony and cartilaginous external auditory canal. It was a clinico-anatomic study which included 15 patients who underwent parotidectomy for various indications and 15 cadavers from the laboratory of human anatomy. Results: PBDM is the most reliable and consistent landmark. Conclusion: Considering the variation in distances of these landmarks from the FNT as reported by various authors, the closest landmark is not necessarily the best or the most identifiable and more than one landmark may need to be used for the safe identification of the FNT.

Clinicoanatomical Study of Foramen Magnum and its Significance in Surgeries

Clinicoanatomical Study of Foramen Magnum and its Significance in Surgeries

Innervation of the anconeus epitrochlearis muscle: MRI and cadaveric studies.

Ulnar neuropathy at the cubital tunnel is common. However, a rare form of ulnar neuropathy here is due to compression from an accessory muscle, the anconeus epitrochlearis. Reports in the literature regarding the details of this muscle's innervation are vague, so the aim of the present study was to characterize this anatomy more clearly. This was a combined review of magnetic resonance imaging (MRI) from patients with an anconeus epitrochlearis and ulnar neuropathy and cadaveric dissections to characterize the innervation of this variant muscle. A review of 11 patients and three reports of ulnar neuropathy and an anconeus epitrochlearis in the literature revealed no MRI changes consistent with acute denervation of this muscle. However, in two cases, there were signs of chronic denervation of the muscle. Dissection of five cadavers revealed that the nerve supply to the anconeus epitrochlearis originated proximal to the medial epicondyle, traveled parallel to the ulnar nerve, terminated on the deep aspect of this muscle, and had a mean length of 60 mm. This clinicoanatomical study provides evidence that the innervation of the anconeus epitrochlearis is proximal to the muscle and on its deep aspect. Clin. Anat. 32:218-223, 2019. © 2018 Wiley Periodicals, Inc.

Cystic neck swellings: A clinico-anatomical study

Cystic neck swellings: A clinico-anatomical study

Anatomy of the cutaneous lymphatic system of the trunk: a clinico-anatomical study of 90 cutaneous melanomas.

The cutaneous lymphatic system of the trunk is a complex network, the anatomical knowledge of which remains unclear. The lymphatic system plays a major role in the dissemination of lymphophilic cancers like melanomas. The aim of this study was to improve our knowledge, optimize the care of patients with cutaneous tumors of the trunk, and to use our clinical experience of the topography of pathologic lymph nodes related to cutaneous melanomas and depicted by lymphoscintigraphy. This prospective study included 90 consecutive patients who had primary resection of cutaneous melanoma of the trunk between June 2011 and January 2015. All patients had lymphatic mapping by lymphoscintigraphy, followed by sentinel lymph node procedure. We compared data of lymphatic imaging (lymphoscintigraphy and SPECT-CT) and surgery. We divided the trunk into 36 regions based on cutaneous anatomical landmarks to determine the topography of the lymphatic system for each tumor. Our study showed cutaneous lymphatic drainage of melanomas of the trunk in 16 different areas. This drainage could be single or multiple. We observed that drainage could be controlateral in medial regions of the trunk, and lymphatic pathway could be retrograde. This drainage could be bilateral for medial regions and mainly into axillary areas for regions above L1 level. Posterior regions of the trunk had more diversity of drainage areas than anterior regions. Cutaneous lymphatic drainage of the trunk was not limited to axillary and inguinal areas, showed interindividual variability, and was single or multiple, unilateral or bilateral, and unpredictable.

Bilateral high branching pattern of femoral nerve – A clinico-anatomical study

Objective: The aim of reporting this case is to highlight the abnormal or higher branching pattern of the femoral nerve which is very rarely reported. Materials and Methods: The present anomaly was detected during routine course of cadaveric dissection of a 60 year old male cadaver. Result: The present case reports a very early division of the femoral nerve on both sides of the thigh of a 60 years old male cadaver. The femoral nerve descended through the psoas major muscle and divided into two branches; anterior and posterior, 4.1 cm above the midpoint of the inguinal ligament. Conclusion: Knowledge of this kind of variation in the branching pattern of femoral nerve has much academic and clinical value. Furthermore it will be extremely helpful to the surgeons to prevent iatrogenic injury to femoral nerve and for the anaesthetist to give successful block in the femoral nerve.

Clinicoanatomic study of optimal arthroscopic approaches to the elbow

The purpose: development and topographic substantiation of optimal arthroscopic approaches to the elbow, taking into account the location of the neurovascular structures in different functional positions. Material and methods: Anatomical relationships of elbow nerves and bony structures were studied by dissection of non-fixed anatomical material (6 elbow joints). To investigate the variant anatomy of the brachial artery, MRI in 23 patients were performed. In 10 patients the authors used ultrasound to study the topographic relationships of elbow nerve structures at different functional positions of the upper extremity Variability of the brachial artery deviation, depending on the angle of elbow flexion, was studied in six angiograms of non-fixed anatomical material. Statistical analysis was performed using Instant + and Past 306 software. Results: It was found that elbow flexion of 180°-90° moves the brachial artery away from the bones with a maximum distance from the humerus of 5 cm above the joint space. Distance increases from 23.5±3.1 mm to 23.9±3.1 mm. In 90° elbow flexion radial and median nerves are at the maximum distance from bony structures - 16.01±0.43 and 20.48±0.28 mm, respectively. Conclusion: These findings allowed justification of the conclusion that the lateral arthroscopic approaches to the elbow are the safest. It is possible to perform two lateral arthroscopic approaches: optical and instrumental, without conflict with major neurovascular structures. The optimal position for the surgery is 90° elbow flexion.

Comparative clinicoanatomical study of ilium and fibula as two commonly used bony donor sites for maxillofacial reconstruction

We assessed the morphological characteristics and dimensions of the ilium and fibula to evaluate the suitability of particular areas of bone for use as donor sites for dental reconstructions that carry implants. We measured the dimensions of 130 bilaterally harvested ilium and fibula bones from 65 adult cadavers using osteometric methods, and analysed the effects of age, sex, and side. Dimensions at measuring points, overall suitability for implantation, and relations among age, sex, and side, were evaluated statistically. We report observations of bone morphology involving cross-sections, and clinical relevance. Although the mean dimensions of the fibula and iliac crest were adequate, some segments would not support an implant 10mm long and 3.5mm wide. The overall suitability of parts of the iliac block fell to 30%. Fibular morphology is characterised by constant height and width, and relation of cortical and cancellous bone. Bony dimensions on the iliac fossa and fibula were significantly greater in men than in women. Age had a negative impact in one area of the iliac fossa, but nowhere on the iliac crest. Side was not significant. We found differences in dimensions and morphology between measuring points on the same bone. Precise knowledge about which areas of the donor sites can reliably provide sufficient bone to carry implants after reconstructions will allow greater flexibility and safety when reconstructions are designed.

P2. Theta burst stimulation over left posterior parietal cortex interferes with imitation of gestures

Clinico-anatomical studies have shown that, after brain damage, the ability to imitate meaningless and meaningful gestures may be selectively affected suggesting that different posterior parietal structures may be involved (dual route model). The aim of the present study was therefore to investigate the effect of imaging-guided neuro-navigated continuous theta burst stimulation (cTBS) on the imitation domain over inferior (IPL) and superior parietal cortex (SPL). We hypothesized that SPL stimulation mainly affects meaningless and IPL stimulation predominantly meaningful gestures. Twelve healthy subjects participated in this study. All subjects underwent structural MRI acquisition to be used for imaging guided neuro-navigation cTBS. Participants were targeted with one train of cTBS in three experimental sessions: sham stimulation over vertex and real cTBS over left SPL and IPL, respectively. The imitation task was performed ‘offline’ including 24 meaningless and 24 meaningful (communicative and tool-related). cTBS over left posterior parietal cortex, irrespective of whether IPL or SPL was stimulated, significantly affected gestural imitation. By contrast, differential effects on gesture subtypes (meaningless versus meaningful) could not be detected. The present study shows that a single train of cTBS over left posterior parietal regions significantly interferes with gestural imitation confirming the domain-specific role this region has. However, the findings do not support the predictions based on the dual route model.

Sources of calretinin inputs to motoneurons of extraocular muscles involved in upgaze.

Recent monkey studies showed that motoneurons of the oculomotor nucleus involved in upward eye movements receive a selective input from afferents containing calretinin (CR). Here, we investigated the sources of these CR-positive afferents. After injections of tract-tracers into the oculomotor nucleus (nIII) of two monkeys, the retrograde labeling was combined with CR-immunofluorescence in frozen brainstem sections. Three sources of CR inputs to nIII were found: the rostral interstitial nucleus of the medial longitudinal fascicle (RIMLF), the interstitial nucleus of Cajal, and the y-group. CR is not present in all premotor upward-moving pathways. The excitatory secondary vestibulo-ocular neurons in the magnocellular part of the medial vestibular nuclei contained nonphosphorylated neurofilaments, but no CR, and they received a strong supply of large CR-positive boutons. In conclusion, the present study presents evidence that only specific premotor pathways for upward eye movements--excitatory upgaze pathways--contain CR, but not the up vestibulo-ocular reflex pathways. This property may help to differentiate between premotor up- and downgaze pathways in correlative clinico-anatomical studies in humans.

The stylomastoid artery as an anatomical landmark to the facial nerve during parotid surgery: a clinico-anatomic study

BackgroundThe identification of the facial nerve can be difficult in a bloody operative field or by an incision that limits exposure; hence anatomical landmarks and adequate operative exposure can aid such identification and preservation.In this clinico-anatomic study, we examined the stylomastoid artery (SMA) and its relation to the facial nerve trunk; the origin of the artery was identified on cadavers and its nature was confirmed histologically.MethodsThe clinical component of the study included prospective reviewing of 100 consecutive routine parotidectomies; while, the anatomical component of the study involved dissecting 50 cadaveric hemifaces.ResultsWe could consistently identify a supplying vessel, stylomastoid artery, which tends to vary less in position than the facial nerve. Following this vessel, a few millimetres inferiorly and medially, we have gone on to identify the facial nerve trunk, which it supplies, with relative ease. The origin of the stylomastoid artery, in our study, was either from the occipital artery or the posterior auricular artery.ConclusionThis anatomical aid, the stylomastoid artery, when supplemented by the other more commonly known anatomical landmarks and intra-operative facial nerve monitoring further reduces the risk of iatrogenic facial nerve damage and operative time.

Cessation of Dreaming and Ventromesial Frontal-region Infarcts

Freud attributed the primary instigator of dreaming to the “libidinal drive” in his theory. Research support for this classical psychoanalytic theory was provided in Solms’s clinico-anatomical studies. He found that damage to the ventromesial frontal pathway caused both global cessation of dreaming and a reduction in motivated behaviour. However, most of the patients in Solms’s clinical series were cases of tumor and diffuse injury. These conditions rendered the localization work difficult and imprecise. In view of this, the present study investigated the association between dream cessation and lesions to the ventromesial frontal region in patients who were diagnosed with infarctions. Solms’s findings were largely replicated. In addition, results from the present study indicated that compared to the other neural components in the ventromesial frontal pathway, the role of the caudate nucleus appeared to be particularly salient in the functional architecture of dreaming.

A clinicoanatomical study of the novel nerve fibers linked to stress urinary incontinence: The first morphological description of a nerve descending properly along the anterior vaginal wall

When performing anterior colporrhaphy for cystocele, most pelvic surgeons have not considered the neuroanatomy that contributes to urethral function. The aim of the study was to anatomically identify nerve fibers located in the anterior vagina associated with the pathogenesis of incontinence and pelvic organ prolapse. Anterior vaginal specimens were obtained from 17 female cadavers and 33 cases of clinical cystocele by anterior vaginal resection. The specimens were step-sectioned and stained with hematoxylin-eosin, S100 antibody, and tyrosine hydroxylase antibody. As a result, descending nerves 50-200 microm in thickness were identified between the urethra and vagina. They were located more than 10 mm medially from a cluster of nerves found almost along the lateral edge of the vagina and stained with S100 and tyrosine hydroxylase antibody, originated from the cranial part of the pelvic plexus, and appeared to terminate at the urethral smooth muscles. The authors classified the density of S100 positive nerve fibers in the anterior vaginal wall obtained from clinically operated cases of cystocele into three grades (Grade 1, nothing or a few thin nerves less than 20 microm in diameter; Grade 2, thick nerves more than 50 microm in diameter and thin nerves; Grade 3, more than 3 thick nerves in one field at an objective magnification of 40x). Mean urethral mobility (Q-tip) values (28.1 degrees +/-+/- 19.6 degrees ) observed in the Grade 3 cases was significantly lower than those (50.0 degrees +/-+/- 27.4 degrees and 59.4 degrees +/-+/- 19.9 degrees ) in Grade 2 and Grade 1, respectively. In addition, the presence of preoperative or postoperative stress urinary incontinence in the cases of Grade 1 was significantly higher than those of the cases with S100 positive stained nerves. In conclusion, the novel nerve fibers immunohistochemically identified in the anterior vaginal wall are different from those of the common nervous system or the pelvic floor and are associated with the pathogenesis of urethral hypermobility.

Memory Loss Is Not Equal to Loss of Dream Experience: A Clinicoanatomical Study of Dreaming in Patients with Posterior Brain Lesions

This paper examines the role of the posterior brain in the functional architecture of dreaming, and the controversy surrounding dream cessation caused by memory failure. Eight patients with posterior brain lesions were assessed on a daily basis, using neuropsychological assessment, and morning sleep and dream interviews. It was found that the sole nondreaming patient was no more impaired in memory than the 7 patients who retained their dreaming capacity. Based on these findings, the author puts forward two arguments: (1) There is a clear distinction between memory deficits and cessation of dreaming. The inability to recall dreams and the loss of dream experience are rare in stroke patients, although memory disorders are not. (2) Unilateral lesions to the supramarginal gyrus and its adjacent areas do not necessarily lead to cessation of dreaming. In addition, the author discusses the neuropsychoanalytic implications of the findings.

Whither Neuropsychiatry?

Whither Neuropsychiatry?

Why Did Empirical Dream Researchers Reject Freud? A Critique of Historical Claims by Mark Solms.

Neuropsychologist and psychoanalyst Mark Solms (1997) made a major contribution to dream research through his clinico-anatomical studies, which reveal the outlines of the neural network that underlies dreaming. However, in more recent work he misunderstands the history of the rapid eye movement (REM)/non-REM (NREM) controversy in a Freudian-serving way and ignores the considerable systematic empirical evidence that contradicts the key claims of the Freudian dream theory he is trying to revive. After summarizing Solms’s claims about the history of laboratory dream research, this article suggests a different version of that history and summarizes the empirical findings that explain why Freudian theory is not considered viable by most dream researchers.

Anatomical basis for a successful upper limb sympathectomy in the thoracoscopic era.

In this clinico-anatomical study, factors potentially responsible for unsuccessful upper limb sympathectomy (ULS) by the thoracoscopic route were evaluated. This study comprised two subsets: 1) in the clinical subset, 25 patients (n = 50 sides) underwent bilateral second thoracic ganglionectomy for palmar hyperhidrosis, and factors predisposing to unsuccessful ULS were identified; and 2) in the anatomical subset, the neural connections of the first and second intercostal spaces were bilaterally dissected in 22 adult cadavers (22 right, 21 left; n = 43 sides). Alternate neural pathways (ANP) were noted in 9 of 50 sides in the 25 clinical cases (18%). In three asthenic patients (5 sides), fascia overlying the longus colli muscle mimicked the sympathetic chain. The right superior intercostal vein (SIV) was located anterior to the second thoracic ganglion in 6 of 50 sides (12%) and predisposed to troublesome bleeding in 2 of 50 cases; the SIV was posterior to the ganglion in 19 of 50 sides (38%), posing no technical problem. On the left, the SIV was noted outside the field of dissection in all but one case. A successful outcome to sympathectomy was noted in all 25 patients. A spectrum of sympathetic contributions to the first thoracic ventral ramus for the first intercostal space was noted in 37 of 43 anatomical cases (86%). These were categorized according to the arrangements of the intrathoracic ramus between the second intercostal nerve and the first thoracic ventral ramus. The cervicothoracic ganglion (37/43 cases; 86%) and an independent inferior cervical ganglion (6/43 cases; 14%) were always located above the second rib. The second thoracic ganglion was consistently located in the second intercostal space. This study demonstrates that ANPs have little clinical significance when a second thoracic ganglionectomy is undertaken. Technical failures may be avoided if the surgeon is mindful of anatomical variations at surgery.

Jean-Martin Charcot (1825-1893). The man behind the joint disease.

Jean-Martin Charcot was one of the most celebrated French physicians of the 19th century. A masterful teacher and a captivating lecturer, Charcot created the foundations of neurology as an independent discipline, and transformed the Salpêtrière hospital, in Paris, into one of the world's greatest teaching centers for clinical neurologic research. His name is attached to the distinct pathologic entity, Charcot's joint disease, that he so meticulously described. This article reviews the highlights of Charcot's career and his clinicoanatomic studies of patients with tabetic arthropathies.

Limb Apraxia: Cortical or Subcortical

Ideomotor apraxia is defined as a disturbance in timing, sequencing, and spatial organization of gestural movements. Left hemisphere motor dominance reflected by ideomotor apraxia mainly refers to spatially and temporally complex movements performed outside the natural context. While clinicoanatomical studies have failed to unveil a specific lesion correlating with apraxia, white matter damage—interrupting corticocortical and corticosubcortical connections—seems crucial for the deficit to be persistent and severe. Patients with basal ganglia lesions and disorders, such as Parkinson's disease and progressive supranuclear palsy, may exhibit ideomotor apraxia. The putative roles of the basal ganglia in object-oriented action, and therefore in praxis, would include among others (a) the selection of the kinematic parameters and the direction of arm movements, (b) working as an integral part of brain systems involved in timing and representation of action sequences, (c) encoding behavioral context, and (d) working as a subcortical component of the parietofrontal circuits devoted to sensorimotor transformation (e.g., reaching). Several studies suggest that basal ganglia pathology per se may not cause overt apraxia. However, when it is combined with dysfunction of the cortical components of the neural systems involved in sequencing, sensorimotor transformation, and response selection, different types of ideomotor praxis deficits would become clinically manifested.