Halil İbrahim Açar

Is there a safe area for the axillary nerve in the deltoid muscle? A cadaveric study.

BACKGROUND Several authors have defined a variety of so-called safe zones for deltoid-splitting incisions. The first aim of the present study was to investigate the distance of the axillary nerve from the acromion and its relation to arm length. The second aim was to identify a safe area for the axillary nerve during surgical dissection of the deltoid muscle. METHODS Twenty-four shoulders of embalmed adult cadavers were included in the study. The distance from the anterior edge of the acromion to the course of the axillary nerve was measured and was recorded as the anterior distance. The same measurement from the posterior edge of the acromion to the course of the axillary nerve was made and was recorded as the posterior distance for each limb. Correlation analysis was performed between the arm length and the anterior distance and the posterior distance for each limb. The ratios between arm length and the anterior and posterior distances were calculated for each case and were recorded as an anterior index and a posterior index. RESULTS The average arm length was 30.40 cm. The average anterior distance was 6.08 cm, and the average posterior distance was 4.87 cm. There was a significant correlation between arm length and both anterior distance (r = 0.79, p < 0.001) and posterior distance (r = 0.61, p = 0.001). The axillary nerve was not found to lie at a constant distance from the acromion at every point along its course. The average anterior index was 0.20, and the average posterior index was 0.16. CONCLUSIONS The present study describes a safe area above the axillary nerve that is quadrangular in shape, with the length of the lateral edges being dependent on the individuals arm length. Using this safe area should provide a safe exposure for the axillary nerve during shoulder operations.

Posterior osseous bridging of C1

The sulcus of the vertebral artery is located behind the lateral mass of the atlas and in some cases is converted into a foramen by anomalous ossification known as the posterior ponticulus (osseous bridge). This study involved anatomical observations of 158 isolated anatomical specimens of dry C1 vertebrae. The incidence and types of posterior osseous bridging were identified for the 158 dry samples of atlas vertebrae. In nine (5.6%) dry C1 vertebrae, partial osseous bridging was detected (bilaterally in eight vertebrae and unilaterally on the left in one). Complete osseous bridging (arcuate foramen) was observed in six (3.8%) dry C1 vertebrae (bilaterally in one vertebra, unilaterally on the left in three, and on the right in two). Awareness of the types of posterior osseous bridging of C1 in craniocervical junction surgery is essential, and may be helpful in surgical interventions in this region.

The Annular Ligament An Anatomical Study

Background Despite documentations of ligamentous structures of the elbow, the anatomy and clinical and functional importance of the annular ligament has not been comprehensively defined in the orthopaedic literature. Hypothesis The annular ligament is an important component of both the proximal radioulnar and humeroradial joints, as well as an important component of the neighboring muscles and ligaments. Study Design Descriptive laboratory study. Materials and Methods To investigate the annular ligament and its relationship with neighboring structures, macroscopic and microscopic dissections were performed on both upper extremities of 30 cadavers (12 female and 18 male) fixed in 10% formaldehyde and on 1 upper extremity of a fresh cadaver (male). Results The distal ulnar insertion of discrete fibers on the supinator crest was defined as the inferior oblique band of the annular ligament, and the proximal insertion of the annular ligament was defined as the superior oblique band of the annular ligament. These patterns were noted in all specimens. It was difficult to distinguish the fibers of the supinator muscle in every specimen because they were intimately fused with the fibers of the annular ligament. Conclusions The superior and inferior oblique bands of the annular ligament attached proximally and distally onto the ulna, thus helping to secure the annular ligament in place.

Retropharyngeal space and lymph nodes: an anatomical guide for surgical dissection.

Conclusions Identification of the alar fascia is the key part of surgical dissection of the retropharyngeal lymph nodes (RPLNs). In cases where mandibulotomy is not performed for the removal of the primary tumor and/or the posterior pharyngeal wall is not incised, the medial or lateral approaches described in this paper can be performed. Objective Surgical dissection of the RPLNs may improve prognosis and locoregional control in oropharyngeal, hypopharyngeal and cervical esophageal carcinomas. There have been no previous anatomical studies concerning landmarks and approaches for the surgical dissection of the RPLNs. This study was designed to illustrate the fascial anatomy of the retropharyngeal region (RPR), provide anatomical guidelines for RPLN dissection and describe and compare approaches for surgical removal of the RPLNs. Material and methods Twelve fixed cadavers were used. Slices were obtained from the necks of the first three cadavers and the RPRs of the slices were dissected under an operating microscope. The other nine cadavers were dissected in a surgical position to expose the RPLNs and the fasciae of the RPR. Results In the coronal plane, the alar fascia divides the space between the buccopharyngeal and prevertebral fasciae into two compartments and constitutes the posterior border of the retropharyngeal space, which contains the RPLNs. The alar fascia, an important landmark for reaching the RPLNs, can be identified by the cervical sympathetic trunk, superior sympathetic ganglion and superior laryngeal nerve. Two approaches can be performed to remove the RPLNs, namely medial or lateral to the internal and external carotid arteries, internal jugular vein and vagus nerve.

Evaluation of the longus colli muscle in relation to stellate ganglion block.

Background and Objectives: The longus colli (LC) muscle is an important structure of the anterior cervical spine and has a critical role in stellate ganglion block. This technique involves withdrawing the needle to locate its port for injection above the anterior surface of the LC muscle; however, its exact thickness at the C5, C6, and C7 levels has not been measured. The aim of this anatomic and magnetic resonance-supported study was to evaluate the thickness of the LC muscle at these levels from the anterior tubercle of each vertebra toward the vertebral body at 5-, 10-, and 15-mm distances to provide precise anatomic data for stellate ganglion block. Methods: Ten cadavers, 60 vertebral body specimens, and cervical magnetic resonance imaging (MRI) scans of 40 adult patients were used for measurements. Results: The main findings of this study are that the thickness of the LC muscle varies between 5.0 and 10.0 mm at C6 and C7 in cadavers and between 8.0 and 10.0 mm in MRI scans. Sex has an important role; MRI scans revealed that male patients have a considerably thicker LC muscle at each vertebral level. Conclusion: We found a highly variable thickness of the LC muscle in anatomic and imaging studies, which may lead to negative block results.

Unusual origin and course of the testicular arteries

BackgroundThe testicular arteries usually arise from the anterolateral aspect of the abdominal aorta just inferior to the renal arteries at the level of the second lumbar vertebra. However, they may also originate from the renal artery, middle suprarenal artery, one of the lumbar arteries, common or internal iliac artery, or the superior epigastric artery.MethodsAn unusual origin of the right testicular artery and an unusual course of the left one were observed during routine dissection of the retroperitoneal space of a 43-year-old male cadaver.ResultsThe right testicular artery originated from the inferior segmental branch of the right renal artery. After the left testicular artery originated from the anterolateral surface of the abdominal aorta just inferior to the left renal artery it was located between the left renal vein and the left renal artery and descended anterior to the renal vein. Thereafter it coursed on its normal route distally with the testicular vein.ConclusionsAwareness of variations of the testicular arteries, such as that shown in this case, is important during surgical and radiological procedures pertaining to kidney.

Dynamic article: surgical anatomical planes for complete mesocolic excision and applied vascular anatomy of the right colon.

BACKGROUND: Lower local recurrence rates and better overall survival are associated with complete mesocolic excision with central vascular ligation for treatment of colon cancer. To accomplish this, surgeons need to pay special attention to the surgical anatomical planes and vascular anatomy of the colon. However, surgical education in this area has been neglected. OBJECTIVE: The aim of this study is to define the correct surgical anatomical planes for complete mesocolic excision with central vascular ligation and to demonstrate the correct dissection technique for protecting anatomical structures. DESIGN AND SETTINGS: Macroscopic and microscopic surgical dissections were performed on 12 cadavers in the anatomy laboratory and on autopsy specimens. The dissections were recorded as video clips. METHODS: Dissections were performed in accordance with the complete mesocolic excision technique on 10 male and 2 female cadavers. Vascular structures, autonomic nerves, and related fascias were shown. Within each step of the surgical procedure, important anatomical structures were displayed on still images captured from videos by animations. RESULTS: Three crucial steps for complete mesocolic excision with central vascular ligation are demonstrated on the cadavers: 1) full mobilization of the superior mesenteric root following the embryological planes between the visceral and the parietal fascias; 2) mobilization of the mesocolon from the duodenum and the pancreas and identification of vascular structures, especially the veins around the pancreas; and 3) central vascular ligation of the colonic vessels at their origin, taking into account the vascular variations within the mesocolonic vessels and the autonomic nerves around the superior mesenteric artery. LIMITATIONS: The limitation of this study was the number of the cadavers used. CONCLUSIONS: Successful complete mesocolic excision with central vascular ligation depends on an accurate knowledge of the surgical anatomical planes and the vascular anatomy of the colon.

Variations in the Vascular Anatomy of the Right Colon and Implications for Right-Sided Colon Surgery.

BACKGROUND: Knowledge of the normal pattern and variations of the blood supply of the right colon is crucial for better outcomes after colon surgery. OBJECTIVE: The purpose of this study was to describe the precise vascular anatomy of the right colon according to surgical perspective. DESIGN: Adult fresh cadavers were dissected between January 2013 and October 2015, focusing on the venous and arterial anatomy of the right side of the colon. SETTINGS: Macroscopic anatomical dissections were performed on 111 adult fresh cadavers with emphasis on the vascular anatomy of the right colon. The colic tributaries of the superior mesenteric artery and vein were documented in writing. Furthermore, the dissections were recorded with a video camera. RESULTS: The incidence of colic arteries arising from the superior mesenteric artery included ileocolic artery, 100%; right colic artery, 33.3%; middle colic artery, 100%; and accessory middle colic artery, 11,7%. All 111 cadavers had a single ileocolic vein, which drained into the superior mesenteric vein in 103 cases (92.8%), into the gastro-pancreatico-colic trunk in 7 cases (6.3%), and into the jejunal trunk in 1 case (0.9%). The drainage site of the ileocolic vein to the superior mesenteric vein varied, and in 9% of cases the ileocolic vein did not accompany the ileocolic artery. The gastro-pancreatico-colic trunk was detected in 87 cases (78.4%); with several forms of the origin of the respective branches, the gastropancreatic trunk was detected in 24 cases (21.6), and the classic gastrocolic trunk of Henle was not detected. Variations were found in the formation and drainage routes of other venous colic tributaries of the superior mesenteric vein. LIMITATIONS: This study is limited by its use of cadavers in that it is impossible to trace each vessel to its origin in live surgery. CONCLUSIONS: Surgeons must watch, observe, and bear in mind that vascular variations can occur. Awareness of these complex variations may improve the quality of surgery and may prevent devastating complications during right-sided colon resections.

Perineal and pelvic anatomy of extralevator abdominoperineal excision for rectal cancer: cadaveric dissection.

BACKGROUND: Circumferential margin positivity and tumor perforations are the main reasons for the poor oncological outcome following standard abdominoperineal excision for low rectal cancer. The extralevator abdominoperineal excision approach has been developed to avoid “coning down” or “surgical waisting”; however, surgical education in this area has been neglected. PURPOSE: This study aims to define correct surgical anatomical planes for extralevator abdominoperineal excision and show the differences in excision planes between standard and extralevator abdominoperineal excision. DESIGN AND SETTING: Macroscopic surgical dissections were performed in a clinical anatomy laboratory. The dissections were recorded as video clips. METHODS: In accordance with the surgical technique of extralevator abdominoperineal excision, abdominal and then perineal dissections were performed on 1 female and 5 male cadavers. Neurovascular, muscular, and fascial structures located in or near the excision field were carefully revealed. RESULTS: The surgical planes of extralevator abdominoperineal excision, which widen the tumor-free margins and prevent inadvertent bowel perforation, are described in this step-by-step anatomical dissection study. Within the surgical excision planes, sacral vessels and sympathetic chains form a neurovascular network at the level of the sacrococcygeal joint. Although pelvic autonomic plexuses were away from the lateral incision line, their branches extending to urogenital organs were very close to the anterolateral dissection line. Perineal dissection showed that the internal pudendal vessels and pudendal nerve were close to the lateral excision plane. The superficial transverse perineal muscle and perineal body were the most important landmarks to determine the anterior boundary of dissection. LIMITATIONS: The study focused on the perineal dissection of extralevator abdominoperineal excision. CONCLUSIONS: Successful extralevator abdominoperineal excision crucially depends on an accurate knowledge of surgical anatomical planes.

Important points for protection of the autonomic nerves during total mesorectal excision.

BACKGROUND:One of the most important aspects for patients undergoing rectal cancer surgery is quality of life, which is closely related to postoperative sexual, urinary, and bowel functions. To preserve these functions, surgeons need to pay special attention to the fascial planes and autonomic nerve plexuses. OBJECTIVE:The aim of this study is to describe the locations of autonomic nerves in critical areas and to demonstrate the correct surgical planes for protecting these nerves during total mesorectal excision. DESIGN AND SETTINGS:Macroscopic and microscopic surgical dissections were performed in the anatomy laboratory. The dissections were recorded as video clips. METHODS:Dissections were performed in accordance with the total mesorectal excision technique down to the pelvic floor on 2 female and 7 male cadavers. Autonomic nerves and related fascias were shown. RESULTS:Autonomic nerves can be damaged during total mesorectal excision in 4 crucial areas: around the origin of the inferior mesenteric artery, in front of the promontory, the side walls of the pelvis, and the posterolateral corners of the prostate close to the anterior rectal wall. Fibers extending in front of the aorta and fibers coming from the sympathetic trunks combine to form the inferior mesenteric plexus around the origin of the inferior mesenteric artery. Most of the fibers that form the superior hypogastric plexus were fibers going downward from the inferior mesenteric plexus. The erigent nerves merge with the pelvic plexuses through the fascia of piriformis, which is part of the pelvic parietal fascia. LIMITATIONS:The number of cadavers should be increased, especially the number of female cadavers. CONCLUSIONS:The autonomic nerves must be protected during rectal cancer surgery to maintain the patient’s quality of life. Therefore, knowledge of autonomic nerve positions and their relationship with surgical planes are very important for rectal surgeons.