Multiple cysts of the sacrococcygeal anal region

The plexuses of the lower body include the lumbar, sacral, and coccygeal plexuses, which innervate the abdomen, pelvis, legs, and coccygeal region. These plexuses control the transmission of sensory information and coordinate motor functions of the lower body.
The Lumbar Plexus
The lumbar plexus is situated within the lumbar region of the back and is primarily formed by the first four lumbar spinal nerves (L1 to L4). This plexus extends its branches into several nerves, including the...

Evaluating the rectum and anus plays a crucial role in conducting a thorough physical examination of the gastrointestinal system. Although it may be uncomfortable and often embarrassing for the patient, it holds immense diagnostic value, particularly in detecting gastrointestinal diseases and abnormalities. This guide will explain how to perform this assessment using inspection and palpation methods.
Rectal Inspection
Begin by inspecting the perianal and anal areas for color, texture, rashes,...

The muscles of the pelvic floor and perineum are crucial for supporting the pelvic organs, controlling continence, and aiding in sexual function, childbirth, and core stability. They are typically divided into the superficial perineal layer and the deep pelvic floor layer.
Perineal Layer
The perineum is a diamond-shaped area below the pelvic diaphragm, divided into an anterior urogenital triangle that contains the external genitals and a posterior anal triangle housing the anus. The urogenital...

The large intestine is divided into three main regions: the cecum, colon, and rectum. Extending from the ileocecal valve to the anus, it frames the small intestine on three sides.
The ileocecal sphincter, a mucous membrane fold, guards the opening from the ileum to the large intestine. This valve permits material from the small intestine to pass into the large intestine. Attached to the ileocecal valve is the cecum. This small pouch, approximately 6 cm long, has a twisted, coiled tube known as...

To promote clear communication, for instance, about the location of a patient's abdominal pain or a suspicious mass, anatomists and clinicians typically use imaginary lines to categorize the abdominopelvic cavity into either four quadrants or nine regions to identify organs in the cavity.
The simpler quadrants approach, which is more commonly used in medicine, subdivides the cavity with one horizontal and one vertical line that intersects at the patient's umbilicus (navel). The four quadrants...

Spinal nerves are pivotal conduits in the nervous system, bridging the central nervous system (CNS) with the peripheral nervous system (PNS). These nerves enable a complex communication network between the brain, spinal cord, and the rest of the body, facilitating sensory input, motor output, and autonomic functions.
There are 31 bilateral pairs of spinal nerves, each emerging from the spinal cord through the intervertebral foramina—openings between adjacent vertebrae. These nerves are...