Co-Innervation of Triceps Brachii Muscle with Variant Branch of Ulnar Nerve.

AIM: To evaluate the existence of nerve innervation of the triceps brachii muscle via the ulnar nerve and its clinical importance in terms of nerve transfer or susceptibility to iatrogenic injuries during surgical procedures. MATERIAL AND METHODS: Thirty-five skeletally mature upper extremities of adult cadavers were included in the present study. The ulnar nerve was revealed from the medial cord to the distal part of the cubital fossa. The existence of the branches of the ulnar nerve and communicant branch of the radial nerve was examined in the brachium. The diameter and length of the variant nerve branches were measured. RESULTS: A nerve branch from the ulnar nerve to the triceps brachii muscle was found in five of the dissected extremities (14.7%). The mean length and diameter of the variant nerve branch were 20.2 mm and 1.46 mm, respectively. The mean distance of the muscle entry point of the variant nerve branch from the bi-condylar line was 8.18 cm. CONCLUSION: A variant nerve branch via the ulnar nerve can innervate the medial head of the triceps brachii at the distal third of the brachium. This variant nerve branch will be under risk of iatrogenic injury during elbow surgery and it seems to be an option for nerve grafts.

Trifurcation of the tibial nerve within the tarsal tunnel.

The tibial nerve is the larger terminal branch of the sciatic nerve and it terminates in the tarsal tunnel by giving lateral and medial plantar nerves. We present a rare case of trifurcation of the tibial nerve within the tarsal tunnel. The variant nerve curves laterally after branching from the tibial nerve and courses deep to quadratus plantae muscle. Interestingly, posterior tibial artery was also terminating by giving three branches. These branches were accompanying the terminal branches of the tibial nerve.

Topographical anatomy of cricothyroid membrane and its relation with invasive airway access.

Cricothyroidotomy is a surgical procedure involving penetration through the skin and cricothyroid membrane to maintain airway patency during life-threatening emergency conditions. Complications such as bleeding and laryngeal stenosis can result from it. Our aim in this study was to identify the anatomical structures located on the membrane and to ascertain whether there is a safe area on the membrane for this procedure. Thirty larynx specimens fixed with 10% formaldehyde in the Department of Anatomy were dissected. The cricothyroid artery, the cricothyroid vein, the common artery and vein formed by the cricothyroid vessels, the pyramidal lobe of the thyroid gland and lymph nodes were observed on the membrane. The cricothyroid membrane was divided into four quadrants and the most common locations of these anatomical structures on the membrane were recorded. The cricothyroid artery and vein were located on the upper half of the membrane, the common vein was found in the midline, coursing to the thyroid gland, and the lobus pyramidalis and lymph nodes were located on the left side of the midline. Overall, the anatomical structures were mostly located on the upper half and lower left quadrant of the cricothyroid membrane. Thus, the lower right quadrant seems safer for invasive procedures such as needle cricothyroidotomy or other cannulation techniques. Needle puncture or cannulation through the lower right quadrant of the cricothyroid membrane will injure fewer anatomical structures so there should be fewer complications due to degradation of the vascular supply to this region. Clin. Anat. 29:949-954, 2016. © 2016 Wiley Periodicals, Inc.

The ratios of 2nd to 4th digit may be a predictor of schizophrenia in male patients.

The production of androgens (mostly testosterone) during the early fetal stage is essential for the differentiation of the male brain. Some authors have suggested a relationship between androgen exposure during the prenatal period and schizophrenia. These two separate relationships suggest that digit length ratios are associated with schizophrenia in males. The study was performed in a university hospital between October 2012 and May 2013. One hundred and three male patients diagnosed with schizophrenia according to DSM-IV using SCID-I, and 100 matched healthy males, were admitted to the study. Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS) and Brief Psychiatric Rating Scale (BPRS) were used to assess schizophrenia symptoms. The second digit (2D) and fourth digit (4D) asymmetry index (AI), and the right- and left-hand 2D:4D ratios were calculated. All parametric data in the groups were compared using an independent t-test. The predictive power of the AI was estimated by receiver operating characteristics analysis. The 2D:4D AI was statistically significantly lower in the patient group than the healthy control comparison group. There were significant differences between the schizophrenia and the control groups in respect of left 2D:4D and right 2D:4D. There was no correlation between AI, left, or right 2D:4D, BPRS, or SAPS in the schizophrenia group. However, there was a negative correlation between left 2nd digit (L2D):4D and the SANS score. Our findings support the view that the 2D:4D AI can be used as a moderate indicator of schizophrenia. Even more simply, the right or left 2D:4D can be used as an indicator. L2D:4D could indicate the severity of negative symptoms.

Blood supply of the terminal part of the external branch of the superior laryngeal nerve.

PURPOSE: The external laryngeal nerve (ELN) carries motor fibers to the cricothyroid and inferior pharyngeal muscles. Damage to the nerve may cause symptoms such as a monotone voice. One reason for these symptoms may be nerve injury due to inadvertent stretching, ligation or transaction of the nerve during the dissection of the superior pole of the thyroid gland. We hypothesized a new reason for the symptoms, an insufficient arterial blood supply to the nerve, and investigated this hypothesis. METHODS: From 36 larynges, 52 sides (26 right and 26 left) were dissected under a surgical Zeiss-OpM1 microscope. RESULTS: The arterial branch to the external branch of the superior laryngeal nerve originated from the posterior glandular branch of the superior thyroid artery in 26 (50%) sides, from the anterior glandular branch in 23 (44.23%) sides, from its trunk on one (1.92%) side, from the infrahyoid branch on one (1.92%) side and from the bifurcation of the superior thyroid artery at the level of separation of the anterior and posterior glandular branches on one (1.92%) side. CONCLUSION: Devascularization of the ELN may lead to dysfunction, so this nerve's varied blood supply should be kept in mind when invasive procedures are performed in this region.

Piriformis syndrome: a case with non-discogenic sciatalgia.

Piriformis syndrome is a clinical picture of non-discogenic sciatica caused by compression of the sciatic nerve by the piriformis muscle. It has variable etiologies and the patho-physiology is not fully understood. The major etiology was known to be the spasm, edema and inflammation of the piriformis muscle and sciatic nerve compression of the muscle later on. Patients can be diagnosed immediately with a comprehensive clinical examination and early diagnosis makes the treatment much easier. Diagnosis of the piriformis syndrome, a very rare cause of low back pain, first requires that this syndrome is remembered, and then a differential diagnosis should be performed. A case of piriformis syndrome diagnosed in a patient who presented with low back pain is reported in this study.

Distribution of the hypoglossal nerve at the base of the tongue and its clinical importance in radiofrequency ablation therapy.

AIM: To identify the course of the hypoglossal nerve at the base of tongue and to determine a safe area for the placement ofradiofrequency ablation therapy (RAT) probes to protect the nerve trunk from any damage. MATERIALS AND METHODS: Anatomical structures located at the base of the tongue were investigated in 10 cadaveric human half-heads. On the base of our landmarks, which are clinically important sign points, measurements were made. RESULTS: The safe area was found to be: in the transverse plane, the 1/2 medial part of the half-tongue between the lateral edge and the foramen caecum of the tongue, and in the vertical plane, a 14.5-mm depth. Despite the presence of minor branches of the hypoglossal nerve in this area, we think that the trunk of the nerve would be preserved. CONCLUSION: We suggest that the landmarks that we determined to avoid motor deficit of the tongue will be helpful for clinicians during RAT to the tongue base.

A detailed study of the relationship between the external laryngeal nerve and superior thyroid artery, including its glandular branches.

The external layrngeal nerve (ELN) may be at risk during thyroidectomy. Because the relationship between the ELN and superior thyroid artery (STA) can be variable, we aimed to investigate their relationship in detail. In human cadavers, 81 ELN and STA and their branches were carefully dissected. The position of the nerve was classified as medial (Group I, on 76.5% sides), lateral (Group II, on 20.9% sides), or posterior (Group III, on 2.4% sides) to the origin of the STA. In Group Ia, the nerve did not cross the artery while it did cross the artery in Group Ib. In Group II, the nerve was located lateral to the origin of the artery and crossed it. In Group III, the nerve coursed downward posterior to the artery. In conclusion, the topography of the ELN showed much more variability in its relationship to the STA than is described in the literature. Such variations should be kept in mind during surgery of the anterior neck. It is our hope that such data will decrease surgical morbidity following surgery of the anterior neck.

Branching pattern of the external branch of the superior laryngeal nerve and its clinical importance.

The external branch of the superior laryngeal nerve gives off many branches above the upper pole of the thyroid gland. Differentiating the branch innervating the cricothyroid muscle from the others may be important during surgery. Therefore, we aimed to demonstrate the branching pattern of this nerve in detail. In 34 human cadavers (59 sides), branches of the nerve were exposed and measurements related to them and neighboring structures were made. A cricothyroidal branch was present on all sides. This branch pierced the inferior pharyngeal constrictor muscle 3.9-17.6 mm above, 3.1-9.9 mm below, or at the level of the upper pole of the thyroid gland. On all sides, the nerve provided one or two thyroidal branches. The thyroidal branch was generally thinner than the cricothyroidal branch. But they were equal in size on three (5%) sides. The external laryngeal nerve provided two or three pharyngeal branches on all sides. These branches arose from the nerve 3.5-12.7 mm from the upper pole of the thyroid gland. Although the branch was generally thinner than the cricothyroidal branch, both branches were equal on four (6.7%) sides. Two cardiac branches were observed on two (3.3%) left sides. In conclusion, the cricothyroidal branch was generally thicker than the other branches. But on seven (11.8%) sides, thyroidal or pharyngeal branches and the cricothyroidal branch were equal in size. These data may be important during surgery as the surgeon may confuse the cricothyroidal branch with other branches of the external laryngeal nerve.

Marginal mandibular branch of the facial nerve in human fetuses.

OBJECTIVE: To observe the course of the marginal mandibular branch (MMB) and its relation to the inferior border of the mandible and facial vessels. METHODS: This study was conducted in the Department of Anatomy, Gulhane Military Medical Academy, Etlik, Ankara, Turkey from February 2009 to April 2010. The 44 hemi-face specimens of 22 fetuses were selected for this study, and dissected under a stereomicroscope. The MMB relationship was evaluated between adjacent structures (like vessels and muscles) and the lower border of the mandible. RESULTS: We found a number of one to 4 branches of the MMB. The MMB ran laterally to the facial vein in 42 (95.5%) of the 44 specimens. All the branches of the MMB ran laterally to the facial artery in 30 (68.2%) of the 44 specimens. In 2 specimens, it ran medially to the facial artery. In 10 specimens, the facial artery ran between 2 branches of the MMB. In 2 specimens, the 2 branches of the MMB ran between facial artery and vein. There were no statistical differences between the left and right sides, and in both genders. CONCLUSION: The inferior border of the mandible may be an important landmark to avoid injury to the MMB of the facial nerve. It is for this reason, that surgeons who are willing to operate on this area should have a true knowledge and accurate judgement regarding the anatomy of this branch.