Morphometric analysis of sacral corridor in the upper three sacral segments to prevent neurovascular injury.

Although studies of the sacral corridor dimension have been reported in the European population, little attention has been paid to this issue in the Asian population. The purpose of the study is to estimate the safe dimension of the corridor to avoid neurovascular damage during the fixation of the sacral fracture. The study aimed to examine the cephalocaudal (vertical) and the anteroposterior diameter of the bony passage in the upper three sacral segments. The study further examines the effect of age and sex on corridor dimensions at different sacral levels. Three-dimensionally reconstructed sacra from computed tomography of normal subjects were included in the study. Cephalocaudal and anteroposterior diameters were measured in coronal and axial sections using Geomagic Freeform Plus software. Anteroposterior diameter of the sacral corridor at the first, second, and third sacral segments are significantly higher in males (P=0.013, 0.0011, and <0.0001, respectively). The length of the sacrum also revealed sexual dimorphism (P<0.00016). The anteroposterior diameter of the second sacral segment (ap-S2c) correlated moderately with the first sacral anteroposterior diameter (ap-S1c) (R=0.519, P<0.001). The ap-S2c exhibited a moderate correlation to the third sacral segment (ap-S3c) (R=0.677, P<0.001). The sacral corridor at the level of S1 has the largest cephalocaudal (18.25 mm) and anteroposterior diameter (17.11 mm). Placement of the screw in the first sacral corridor may avoid damage to the neurovascular bundle during the fixation of the sacral fracture.

Morphological, embryological, and clinical implications of the bi-carotid trunk, aberrant right subclavian artery, and bilateral linguofacial trunk.

A female cadaver fixated with 10% formalin solution was dissected during a routine undergraduate anatomy class. It was found that both the right and left carotid arteries arose from a bi-carotid trunk as the first branch of the aortic arch. The bi-carotid trunk was followed by the left subclavian artery. The aberrant right subclavian artery (the last branch) had a retro-oesophageal course. These variations were associated with the linguofacial trunk bilaterally. The group of variant anatomy of vessels encompassing the bi-carotid trunk, aberrant right subclavian artery, and the linguofacial trunk is extremely rare. A similar case has not been reported yet in the literature. The anatomic and morphologic variations of the aortic arch and its branches are important for diagnostic and surgical procedures in the thorax and neck region. Thoracovascular surgeons and interventional radiologists should be aware of these anomalies during head and neck surgery, aortic instrumentation, and four-vessel angiography.

The prevalence and distribution of the variants of Gantzer's muscle: a meta-analysis of cadaveric studies.

The Gantzer's muscle is often present in the flexor compartment of the forearm. It lies underneath flexor digitorum superficialis and compresses the anterior interosseous nerve. Furthermore, this muscle frequently bestows an accessory muscle of flexor pollicis longus or flexor digitorum profundus, or sometimes together. The current meta-analysis aims to compute the prevalence of subtypes of Gantzer's muscle. Major electronic databases (PubMed, Scopus, Google Scholar, etc.) were searched for title and abstract. After removing the duplicate citations, the titles/abstracts were shortlisted with the help of inclusion and exclusion criteria. The shortlisted titles/abstracts were downloaded or collected from the library. The data of all subtypes of Gantzer's muscle were pooled from shortlisted published manuscripts for meta-analysis. The pooled estimate of other anatomical characteristics was also observed. A total of 59 cadaveric studies of sample size 5,903 were evaluated for pooled prevalence of flexor pollicis longus (accessory head). Similarly, the authors evaluated 14 studies of 1,627 upper limbs for flexor digitorum profundus (accessory head). The unit of analysis was per 100 upper limbs. The Pooled prevalence of accessory muscle of flexor pollicis longus and flexor digitorum profundus were 48% (95% CI, 44%-52%) and 17% (95% CI, 13%-21%), respectively. The Gantzer's muscle is present in 2/3rd of the upper limbs. Accessory head of flexor pollicis longus is almost three times more common than the accessory head of flexor digitorum profundus. A classification of Gantzer's muscle is needed to reduce the ignorance of these variants.

Estimation of the relationship between the sacral hiatus and other dorsal sacral parameters using principle component analysis.

PURPOSE: Correct localization of the sacral hiatus is essential for administering a successful caudal epidural block. The purpose of this study is to create a statistical model of sacral hiatus from dorsal sacral parameters to improve the location of the hiatus and thus, reduce the failure rate. The aim of this investigation was to examine the relationship of sacral hiatus morphology and dimension with sacral curvature. This study further examines the dorsal sacral parameters that could affect the sacral hiatus dimension. METHODS: Adult, human, dry sacra and three-dimensionally reconstructed sacra from computed tomography imaging of normal subjects were included in the study and measured using digital Vernier calipers of 0.01 mm accuracy and Geomagic freeform plus software, respectively. RESULT: The most frequent shape of the sacral hiatus was an inverted V (48%) followed by inverted U shape (32%), an irregular shape (12.3%), an M shape (4.7) and an A shape (2.8%). The data were represented by mean and standard deviation. Sacra with M-shaped hiatus had the lowest hiatal length (14.21 ± 5.44 mm), whereas sacra with an inverted V-shaped hiatus had the highest length (25.41 ± 11.3 mm). The anteroposterior diameter of the sacral hiatus at the base in males and females was found to be 3.46 ± 1.48 mm and 2.79 ± 0.83 mm, respectively (P < 0.001). The distance between the caudal end of the median sacral crest and the apex of the sacral hiatus (7.90 ± 6.74 mm, 4.4 ± 5.86 mm) also revealed sexual dimorphism (P < 0.001). CONCLUSION: The correlations between most of the dorsal sacral parameters and length of the sacral hiatus are significant. The intercornual distance is also moderately correlated with the distance between right and left lateral sacral crest S1 level. Dorsal sacral parameters predicts variance of the sacral hiatus dimension from 40 to 73% and this could be utilized for statistical model of the sacral hiatus.

The Ethnic and Geographical Distribution of Fabella: A Systematic Review and Meta-Analysis of 34,733 Knees.

INTRODUCTION: The primary studies demonstrated that fabellar prevalence (FP) varied with ethnic and geographical distribution. Osteoarthritis (OA) and age-related degeneration have a significant association with FP. The prevalence of OA worldwide was doubled with life expectancy. Increased life expectancy has increased exposure to OA and age-related degeneration which could be a possible reason for the rise of FP. The analysis was conducted to provide insight about FP in respect to geographical, ethnic, sex, and laterality distribution. METHODOLOGY: Eighty-six studies were included which have data from 34,733 knee joints. Fifty radiological studies were consisting of 27,293 knees and 36 cadaveric studies had the data of 7,440 knees of dissected specimens, respectively. The prevalence, Odds, and rate ratios were calculated for aging, osteoarthritis, and ethnic variation.  Results: The worldwide FP was 25% (95% CI, 0.22, 0.28). The prevalence of fabella was found to be higher in cadaveric studies (32%) than radiological studies (19%) with significant heterogeneity. The FP was 16-18% till 1950 which was doubled by 2020 (35%). The FP in OA knee was 51% which was thrice of baseline.

A large thymic mass with persistent active tissue in an elderly cadaver.

Thymus is an encapsulated organ having its bilateral origin from the third pharyngeal pouch. It appears to be a single organ but actually it is bilobed. It attains its maximum development at puberty and then it begins to involute. The parenchyma is replaced by adipocytes and lymphocyte production declines. Here we present a large thymus with a small area of persistent active tissue in it which was obtained during routine undergraduate dissection class. Tissues taken from different quadrants of the large thymic mass were processed, embedded in paraffin and sections were taken for hematoxylin and eosin staining which showed presence of thymic tissue in only one quadrant. Further sections from that quadrant was treated with cytokeratin to confirm its epithelial origin. Therefore knowledge of a large persistent thymus will be helpful to the radiologists and surgeons for making differential diagnosis and in avoiding unnecessary surgical intervention.

Giant Gastric Lipoma Presenting as Gastric Outlet Obstruction - A Case Report.

Gartric lipomas are rare. They are mostly small in size, and usually remain asymptomatic. We report a case of giant (14×11cm) gastric lipoma in a 46-year-old male who presented with features of gastric outlet obstruction clinically mimicking gastric malignancy. Upper endoscopy showed a large smooth polypoid mass with broad base arising from posterior wall of gastric antrum with areas of superficial ulcerations. Multiple endoscopic biopsy specimens were nondiagnostic. A computed tomography (CT) scan of the abdomen revealed a huge cauliflower- like intraluminal mass with lobulated surface projecting into gastric lumen and pyloric canal. The mass demonstrated uniform fat density consistent with lipoma. The case is presented to stress the diagnostic problems related to this condition, and emphasize the role of CT in arriving at a correct diagnosis of lipomatous gastrointestinal tract tumours.

Large Tubullo-villous Adenoma of Duodenum Presenting as Gastric Outlet Obstruction.

Tubullo-villous adenoma of duodenum is a rare entity. These are potentially malignant tumours and therefore, complete excision is the treatment of choice. However, at times preoperative diagnosis could not be always achieved posing difficulty in choosing the optimal surgical method of excision. We report a 40-year-old male patient presented with vague upper abdominal pain and vomiting for last 6 months. His computed tomography and endoscopy demonstrated intraluminal polypoidal mass. Endoscopic biopsies were negative for malignancy. Local surgical excision with tumour free margin was performed and histology revealed tubullo-villous adenoma.