Vesico-obturator venous plexus - a rare termination of obturator vein.

Obturator vein usually terminates into the internal iliac vein. Its variations are the cause major bleeding problems in pelvic surgeries. We observed a rare variation in the termination of the right obturator vein. There was a duplication of right obturator vein. Both obturator veins entered the pelvic cavity through the obturator foramen and joined with two vesical veins to form a vesico-obturator plexus. This plexus surrounded the internal iliac artery and terminated into the internal iliac vein. Awareness of this rare variation could be of importance to anatomists, radiologists, gynaecologists, urologists, and orthopaedic surgeons. The plexus might lead to hazardous bleeding in pelvic lymph node clearance procedures, hernia surgeries, gynaecological and orthopaedic procedures in this region. The pelvic fractures too can provoke dramatic retroperitoneal hematomas related to these veins injuries.

A rare femoral venous ladder encircling the femoral artery.

Femoral vein is increasingly used for venous cannulation procedures. Its anomalies in the femoral triangle could complicate these procedures. We report an extremely rare type of femoral venous ladder observed during routine cadaveric dissections. The variation was found in the left lower limb of an adult male cadaver aged 70 years. The femoral vein was a single vein in initial 3 cm and terminal 4 cm of its course. The middle part of the vein showed a duplication and a complex ladder pattern and encircled the femoral artery in the femoral triangle. This anomaly could predispose the vein for deep vein thrombosis. Knowledge of this anomaly could be useful during radiological procedures, femoral hernia repair and femoral triangle abscess and lymph node clearance.

Morphometric analysis of foramen magnum and occipital condyle using CT images for sex determination in a Saudi Arabian population.

OBJECTIVE OF THE STUDY: The objective of this study was to evaluate FM and occipital condyles measurements morphometrically for sex determination by using discriminant function analysis and to note visually the variation in the shape of the foramen magnum in a Saudi Arabian population by using CT scan images. MATERIAL AND METHODS: This study included 472 CT scans (236 males and 236 females; age range, 18-72 years). The foramen magnum shapes were classified into 8 types: oval, egg, round, hexagonal, pentagonal, tetragonal, irregular (A) and irregular (B). The intraobserver and interobserver test was done to calculate the reliability of the measurement. Eight dimensions of the FM and occipital condyle were evaluated to determine the sexual dimorphism using an independent t-test. Sex determination was estimated using discriminate function analysis. RESULTS: The commonest shape of FM was hexagonal and the tetragonal shape was the least common type. Coefficient of reliability (R) was high, ranging between 0.89 and 0.99, which indicates the measurements are reliable and sufficiently precise. All the eight measurements, the FM length and width, FM index, FM area, the width and length of right and left occipital condyles were significantly greater in males than the female. Univariate discriminant function showed an accuracy rate varying from 61% to 66.6% based on FM or occipital condyles measurements. The multivariate analysis of FM and occipital condyle measurements increased the overall accuracy rate of sex determination to 71.6%. CONCLUSION: The univariate analysis of FM and occipital condyle measurements indicates, that the FM area (66.1%), FML (62.5%), FMW (62.5%) and ROCL (62.1%) could be reliable individual variables in sex determination. The multivariate analysis including all the eight variables of FM and occipital condyle increased the accuracy rate of sex determination to 71.6% in determining the sex as male (73.3%) or female (69.9%). The shape of the FM is not useful in sex estimation. The results obtained showed a low degree of sexual dimorphism in the basicranium, the use of this method in forensic anthropology could be helpful for assessment on highly fragmented skull bases.

Sternocleidohyoid muscle: an unreported variant of cleidohyoid muscle.

Sternohyoid, sternothyroid, omohyoid, and thyrohyoid muscles are collectively known as infrahyoid muscles. These muscles frequently show variations in their attachments. Here, an extremely rare variant muscle belonging to this group has been presented. During cadaveric dissection for undergraduate medical students, an additional muscle was found between sternohyoid and superior belly of omohyoid muscles bilaterally in a male cadaver aged approximately 70 years. This muscle took its origin from posterior surface of the manubrium sterni, capsule of the sternoclavicular joint and the posterior surface of the medial part of the clavicle. It was inserted to the hyoid bone between the attachments of sternohyoid and superior belly of omohyoid muscles and was supplied by a branch of ansa cervicalis profunda. There is no report on such a muscle in the literature and it could be named as "sternocleidohyoid muscle". Knowledge of this muscle could be useful in neck surgeries.

Surgical and embryological perspective of a big loop of internal carotid artery extending laterally beyond internal jugular vein.

Knowledge of variations of the internal carotid artery is significant to surgeons and radiologists. The internal carotid artery normally runs a straight course in the neck. Its anomalies can lead to its iatrogenic injuries. We report a case of a large loop of the internal carotid artery in a male cadaver aged about 75 years. The common carotid artery terminated by dividing it into the external carotid artery and internal carotid arteries at the level of the upper border of the thyroid cartilage. From the level of origin, the internal carotid artery coursed upwards, backwards and laterally, and formed a large loop behind the internal jugular vein. The variation was found on the left side of the neck and was unilateral. The uncommon looping of the internal carotid artery might result in altered blood flow to the brain and may lead to misperceptions in surgical, imaging, and invasive procedures.

Fenestrated Falx Cerebri and Additional Sinuses in the Tentorium Cerebelli.

Morphological variations of falx cerebri and tentorium cerebelli are extremely rare. The authors report an extremely rare type of combined variation of falx cerebri and dural venous sinuses in the tentorium cerebelli. During the removal of the brain from cranial cavity, it was noted that the anterior part of the falx cerebri had fenestrations and it looked like a mesh. There was no associated variations of medial surface of cerebrum. Further, there were unusual sinuses within the tentorium cerebelli. Two of them were present in the right half of the tentorium cerebelli and one in the left half of the tentorium cerebelli. There variations could be of importance to radiologists and neurosurgeons. The fenestrations of falx cerebri might lead to misinterpretations in cases of head injuries and the additional sinuses in the tentorium cerebelli might cause unexpected bleeding during surgeries of posterior cranial fossa.

Anomalous Course of Facial Artery Through the Submandibular Gland and its Redundant Loop at the Base of Mandible.

Knowledge of variant course and branching pattern of the facial artery gains importance in the surgeries of upper neck and face. The authors report a unilateral anomalous course and a redundant loop of right facial artery as seen in an adult male cadaver. The right facial artery had its origin from the external carotid artery. It pierced through the submandibular salivary gland and formed a redundant loop at the base of the mandible. Its further course and branching pattern was normal. This case could be important for radiologists, plastic surgeons and craniofacial surgeons.

Transposition and variant termination of azygos and hemiazygos veins: an extremely rare variation.

Azygos system of veins is the main source of venous drainage from the thoracic wall. Knowledge of azygos vein anomalies could be of importance to cardiothoracic surgeons and radiologists. We report a rare variation of azygos vein as seen in an adult male cadaver aged 65 years approximately. The azygos vein was formed by the union of left ascending lumbar and subcostal veins. It coursed upwards on the left side of descending thoracic aorta and crossed the left subclavian artery and the left vagus to terminate into the left brachiocephalic vein. It received left superior intercostal vein and left fifth to eleventh posterior intercostal veins. The hemiazygos and accessory hemiazygos veins were situated on the right side of the vertebral column. They received the right posterior intercostal veins and terminated into the azygos vein at the level of eighth thoracic vertebra.

Saphenous Ladder Formed by Almost Completely Duplicated Great Saphenous Vein.

Knowledge of normal as well as variant great saphenous vein is useful as it is the vein that can get varicosed; the vein that is used in bypass surgeries and the vein that is used for cannulation purpose. We observed almost complete duplication of the great saphenous vein in the left lower limb of an adult male cadaver. Both the great saphenous veins arose from the medial end of the dorsal venous arch and coursed parallel to each other throughout the limb. They united in the femoral triangle to form a short (1 inch long) common great saphenous vein. Common great saphenous vein terminated into the femoral vein. There were four communicating veins connecting the two great saphenous veins in the leg, giving the appearance of a venous ladder. Knowledge of this variation could be extremely useful in treatment of varicose veins of lower limb, in catheterizations and in various surgical procedures of the lower limb.

Jug Handle Tributary of Internal Jugular Vein: A Potentially Dangerous Venous Variation.

Variations of internal jugular vein (IJV) are rare and are surgically important. Here an unreported variation of IJV is presented. Right IJV had an unusual vein joining it in the form of a "jug handle." This vein arose from the junction of IJV and common facial vein (CFV), coursed down for 3 cm and joined IJV again. The CFV was dilated. Knowledge of this rare case could be useful to craniofacial surgeons, radiologists, and anesthesiologists. It might decrease the chances of iatrogenic bleeding during head and neck surgeries and radiologic procedures.

Triple Premasseteric Branches of Facial Artery.

Facial artery is known to show variations in its origin, course, termination, and branching pattern. One of its reported variant branch is called premasseteric branch. During our dissection classes, it was observed that an elderly male cadaver had 3 premasseteic branches arising from the facial artery. The first and second premasseteric branches passed deep to masseter under its anterior border, whereas the third premasseteric branch terminated by anastomosing with the infraorbital artery. This case could be of importance to maxillofacial surgeons, craniofacial surgeons, and plastic surgeons.

Multiple Variations at the Base of an Adult Skull: Implications in Radiology and Skull Base Surgery.

Knowledge of variations at the base of the skull may be important for academic, anthropological, forensic, and clinical purposes, especially in computed tomography and magnetic resonance imaging and while performing safe radical surgery. This report presents multiple variations at the base of an adult Indian skull. The variations noted include the presence of foramen of Civinini bilaterally, absence of carotid canal on the left side, reduced size of foramen lacerum on the left side, presence of petro-occipital foramen bilaterally, asymmetry between the jugular fossae, and asymmetrical occipital condyles. The rare, multiple variations reported here might be useful for neurosurgeons, orthopedic surgeons, and radiologists.

Variant termination of first and second jejunal veins into a "pancreatic portal vein".

Jejunal veins usually terminate into the superior mesenteric vein. Here, an unusual termination of first and second jejunal veins into a pancreatic portal vein has been presented. The common vein formed by the first and second jejunal veins could be named as pancreatic portal vein because it divided into two branches in front of the third part of the duodenum and these two branches entered the head of the pancreas and further divided into smaller branches before anastomosing with the tributaries of pancreatico-duodenal veins. The knowledge of this rare vein could be useful to radiologists and surgeons.

"Anterior appendix": a boon for clinicians and radiologists.

Vermiform appendix is considered as a vestigial organ, and it has minimal or no role to play in the digestion and absorption of food. It is an enigma to the clinicians due to its variable positions and symptoms caused by its inflammation. In the available literature, there are many reports on various positions, size and disease of appendix. However, there is no report on an anteriorly located appendicular attachment to the caecum. During dissection classes for medical undergraduates, an appendix with its base attached to the anterior wall of the caecum was noted. The entire appendix was attached to the ileum through a mesoappendix and was readily visible when the anterior abdominal wall was reflected. This position could be a boon to the clinicians and radiologists during diagnosis and surgery of the appendix.

Two accessory muscles of leg: potential source of entrapment of posterior tibial vessels.

Accessory muscles can be found in any part of the body. In most of the regions, they go unnoticed. However, in some cases, they become symptomatic or of cosmetic concern. In this particular case, the presence of two accessory muscle slips was observed in the flexor compartment of the leg. Among the two, the first accessory muscle belly connected the lower part of flexor hallucis longus to the tibialis posterior. The muscle crossed superficial to the posterior tibial vessels. The second accessory muscle took origin from the connective tissue around the lower part of the posterior tibial vessels and was inserted to the upper part of the lateral border of tibia near the attachment of the interosseous membrane. One of the accessory muscles crossed the posterior tibial vessels, while the other surrounded them. The above accessory muscles were supplied by the branches of tibial nerve.

Double-bellied superior rectus muscle.

Congenital variations of extraocular muscles are rare. We report a double-bellied superior rectus muscle, observed in an adult male cadaver aged 70 years. The superior rectus muscle had two equal-sized bellies, which took separate origins from the common tendinous ring and united to form a common belly 1 cm before the insertion. Due to the duplication, the muscle extended laterally beyond the levator palpebrae superioris. Both its bellies were supplied by oculomotor nerve. To the best of our knowledge, this is the first report on doubling of the belly of the superior rectus muscle.

Accessory Submandibular Salivary Gland Forming a "Horseshoe" With the Main Submandibular Salivary Gland: A Unique Variation.

Presence of accessory submandibular salivary gland (ASSG) is an extremely rare variation. Knowledge of its relations could be very useful to oral and maxillofacial surgeons, head and neck surgeons, and radiologists. During dissection classes, an ASSG was noted between the mylohyoid and hyoglossus muscles. The main submandibular salivary gland had superficial and deep parts. The deep part was narrow and measured about 5 cm. The lingual nerve passed between the superficial and deep parts. The accessory submandibular gland was situated below and parallel to the deep part of SSG. It also measured 5 cm. The ASSG had its own duct, which joined the duct of main gland. The ASSG and the deep part of the SSG were united at the lateral border of geniohyoid muscle to give a characteristic "horseshoe" appearance. The ASSG overlapped both lingual and hypoglossal nerves.

Lingual Nerve Entrapment in Fused Submandibular and Sublingual Salivary Glands: A Unique Finding.

Lingual nerve (LN) is one among the 3 branches of posterior division of mandibular nerve. It might get entrapped in the infratemporal fossa by lateral pterygoid muscle, pterygospinous ligament, or lateral pterygoid plate. Its entrapment in the submandibular region has not been reported yet. A unique entrapment of LN in the fused submandibular and sublingual salivary glands in a cadaver was reported. The deep parts of the submandibular and sublingual salivary glands were completely fused with each other. The LN passed through the center of the fused part. Histologically both submandibular and sublingual salivary glands had both mucous and serous acini. Though this entrapment might not cause any functional problems, it might get injured during various surgical procedures of the submandibular region.

A rare case of atypical thoracodorsal artery: a challenge for flap reconstruction.

The thoracodorsal artery mainly supplies the latissimus dorsi muscle. Anatomical details pertaining to the origin and distribution of thoracodorsal artery are important because the latissimus dorsi myocutaneous flap is one of the most reliable and versatile flaps used in reconstructive surgery. Atypical origin and course of the thoracodorsal artery is, therefore, a challenge for flap reconstruction surgeries. In the present case, we report multiple variations in the branching pattern of axillary artery. The thoracodorsal artery had an unusual origin from the second part of axillary artery. The trunk of thoracoacromial artery was absent. The thoracodorsal artery after its origin, descended downwards over the lateral pectoral region lying deep to pectoralis minor but superficial to teres major muscles. It terminated by supplying the latissimus dorsi muscle. Due to the presence of atypical thoracodorsal branch, the subscapular artery continued as the circumflex scapular artery.

A strange case of superior mesenteric venous collar around the superior mesenteric artery.

During our dissection classes, we saw a venous collar formed around the superior mesenteric artery (SMA) by the jejunal tributaries of superior mesenteric vein in an adult male cadaver. The jejunal tributaries united themselves to form two common jejunal veins. Upper common jejunal vein crossed superficial to SMA and opened into the SMV in front of the uncinate process of pancreas. The inferior common jejunal vein crossed behind the SMA from left to right and opened into the SMV, 4 cm below this level. A communicating vein connected the two common jejunal veins with each other.