Stereological comparison of smooth muscle, collagen, and elastic fibers of the clitoris and glans penis in young adults.

OBJECTIVE: To compare the collagen, elastic fibers, and smooth muscle content of the clitoris and the glans penis in young adults. MATERIALS AND METHODS: The clitoris and the glans penis of six women and six men (mean age 25±3) who died as a result of accidents were excised. The samples were placed under a formaldehyde solution and histologically processed. Masson's trichrome and Weigert's resorcin-fuchsin stain was used to highlight the elastic fibers, smooth muscle, and collagen. Stereological analysis was conducted in 5 random fields of 5 slides for each sample. For statistical analysis, the unpaired t-test was used to compare values between groups, and a value of P<0.05 was considered as significant for all analyses. RESULTS: Stereology revealed a mean smooth muscle content of 35.84±6.46% and 31.64±4.74% for the clitoris and glans penis, respectively, while it also revealed collagen content of 26.11±7.41% and 28.44±3.55% and elastic fibers content of 24.12±4.34% and 30.97±6.13% for the clitoris and glans penis, respectively. The statistical analysis showed no significant differences between them. CONCLUSION: Regardless of anatomical differences, the volumetric density of collagen, elastic fibers, and smooth muscle were similar for the clitoris and glans penis in young adults, a feature possibly explained by their embryology.

Anatole-Felix Le Double (1848-1913): 110 years of his death.

Anatole-Félix Le Double was a prominent figure associated with the concept of anatomical variations also including the comprehension of their anthropological and zoological aspects. As an anatomist, Le Double contributed significantly with his major treatise regarding muscles and bony variants. Furthermore, Le Double influenced and popularized paleoanthropology and its relation to anatomy not only in France but in several parts of the world - promoting the idea that anatomical variations are not only surgically and clinically relevant but also have an evolutionary significance. To celebrate 110 years of his passing, this paper aims to explain his trajectory as a young physician to one of the most important figures in how anatomical variants are perceived today.

Right circumcaval ureter and double right renal vein in the Brazilian shorthair cat (Felis catus): two case reports.

Variations of the renal veins are well described in the literature, although variations concerning the ureter are considered a rare finding in cats. The circumcaval ureter is one of the rarest variations of the ureter and is characterised by a loop of the ureter posterior to the caudal vena cava. This variant is also known as preureteral vena cava and retrocaval ureter. It is thought to be caused by a deviation during embryonic development of the aforementioned vein. Due to its rarity, there are scarce reports of the circumcaval ureter in cats, and its association with two renal veins makes it less common as well. These variations should be preoperatively identified in order to avoid complications in kidney transplants, ureteral surgeries and cystoscopies, for instance. The present work aims to report two cases of a circumcaval ureter with two renal veins in two different Brazilian shorthair cats (Felis catus).

Embryological and comparative description of the cephalic vein joining the external jugular vein: A case report.

The cephalic vein arises from the radial end of the dorsal venous arch. It turns around the radial border of the forearm and passes proximally along the arm to the shoulder, where it enters the axillary vein by penetrating the clavipectoral triangle. The cephalic vein is prone to vary at the antecubital fossa, where it forms numerous anastomoses. A male cadaver fixated with a 10% formalin solution was dissected during regular anatomy lessons. It was found that the cephalic vein crossed the upper third of the arm between two fasciculi of the deltoid muscle and reached the shoulder, where it passed above the acromion and crossed the posterior border of the clavicle in order to join the external jugular vein. The cephalic vein is one of the most used veins for innumerous activities, such as venipunctures and arteriovenous fistula creation. Furthermore, it is an anatomical landmark known for its consistent anatomy, as it possesses low rates of variability. Despite that, its anatomical variations are clinically and surgically significant and healthcare professionals must be aware of the variations of this vessel. We aim to report a rarely described variation of the cephalic vein and discuss its embryological, phylogenetic and clinical features.

Accessory subscapularis muscle - A forgotten variation?

The quadrangular space is a space in the axilla bounded by the inferior margin of the teres minor muscle, the superior margin of the teres major muscle, the lateral margin of the long head of the triceps brachii muscle and the surgical neck of the humerus, medially. The axillary nerve (C5-C6) and the posterior circumflex humeral artery and veins pass through this space in order to supply their territories. The subscapularis muscle is situated into the scapular fossa and inserts itself into the lesser tubercle of the humerus, thus helping stabilize the shoulder joint. A supernumerary muscle known as accessory subscapularis muscle originates from the anterior surface of the muscle and usually inserts itself into the shoulder joint. It is a rare variation with few reports of its existence and incidence. We present a case of the accessory subscapularis muscle in a male cadaver fixated with a 10% formalin solution. The muscle passed anteriorly to the axillary nerve, thus, predisposing an individual to quadrangular space compression syndrome. We perform a review of the literature and address its clinical, anthropological and anatomical significance.