Scientific Illustration

biomedicalephemera:

Gangraena humida pedis - wet gangrene of the foot

Though it can form from any occlusion of blood supply, this gangrenous foot has a particularly interesting origin. 

Following the forcible correction of a flexion contracture due to tuberculosis of the hip-joint, the toes became flexed, cold, and blue. Shortly thereafter, the toes blackened, and fistulae formed on the first and fifth toes, where necrotic bone began to protrude.

As the gangrenous tissue only formed on the end of the foot, it is obvious that there was no full occlusion or rupture of the femoral artery. The physician surmised that the pinched intima of the artery caused thrombosis of a vessel in the foot, and the tissue beyond that point died. 

This case only required the amputation of the anterior portion of the foot and recovered easily.

Iconograms: A Collection of Colored Plates Illustrating Interesting Surgical Conditions. Prof. Bockenheimer, 1913.

(via biomedicalephemera)

biomedicalephemera:

Gluteal muscles

The three primary gluteal muscles (maximus, medius, and minimus), in addition to the tensor fasciae latae (lateral to the primary muscles), comprise the gluteal group, which provides the majority of the support and movement that allows humans to walk upright, rotate our legs, and support our torso.

Each individual muscle is often involved in many different movements, though not always as the primary player. All four gluteal muscles originate from the outer ilium (the back of the “wings” on the pelvis). This is known as the gluteal surface.

Gluteus maximus: (Top Left) The largest muscle in the body. Supports the pelvis, lower torso, and allows the body to remain upright and regain position after stopping movement. Despite claims to the contrary, the gluteus maximus is not what gives the majority of the shape to the buttocks - that’s largely determined by the panniculus adiposus (“hanging fat”) of the buttocks. However, exercising the gluteus maximus may cause fat loss, which gives the impression that it is the primary progenitor of the shape.

Gluteus medius: (Top Center) Originates right below the gluteus maximus. Responsible for abducting the leg and maintaining an upright position while on one leg, such as during running, dancing, or entering a car.

Gluteus minimus: (Top Right) The smallest of the three primary gluteals, works in concert with the gluteus medius to maintain an upright position on one leg, as well as allowing the leg to turn inwards and outwards (medial rotation).

Tensor fasciae latae: (Bottom; near sartorus muscle) Located on the outside edge of the thigh, lateral to the primary gluteals. Causes knee extension, and functions to cause the primary movements during walking. Supported by the gluteus maximus. Used extensively in horseback riding.

Images:
Top: Posterior muscles of the gluteal and thigh region. Gluteus maximus, medius, and minimus highlighted. From Anatomy, Descriptive and Applied. Henry Gray, 1913. Highlighted by Mikael Haggstrom.
Bottom: Structures surrounding the right hip joint, including gluteal muscles. From Anatomy, Descriptive and Applied. Henry Gray, 1908.

biomedicalephemera:

Ganglion cyst, aka “Bible bump”, aka “Let’s hit you with a large book!”

Given the name “Bible cyst” or “Bible bump” from the original “treatment” of hitting the deformity with a Bible or other large book, ganglion cysts are actually considered tumors. Over 60% of the non-cancerous tumors of the hand are ganglionic, but their etiology is still not completely understood.

The first description of these tumors was given by Hippocrates as “knots of tissue containing mucoid flesh”, but the first theories of their origins weren’t put forth until 1746, when one Dr. Eller wrote a descriptive paper on them. He believed that they came from synovial herniation,  or rupture through the tendon sheath, and that they were true cysts.

Later theories recognized that the tumors were growths arising from ganglionic sheaths and not encysted fluids or mucoid tissues, but the old theory of “just smack it with a heavy object to burst it and make the body reabsorb it” still stuck around for a long time. Though bursting the tumor can cause temporary disappearance, this often causes more serious recurrence and additional growth. As these tissues are not cancerous, it’s generally recommended to leave them alone when they’re not interfering with normal function. Sometimes they can press against other tendons or nerves and necessitate aspiration or surgical removal, but the incidence of recurrence is over 40%. In about 75% of cases, the “cyst” will disappear or significantly decrease on its own.

So, yeah, don’t let anyone convince you to let them smack you with a heavy object, just because you have one of these growths! It’s a bad idea to let people smack you with heavy objects, just as a general rule…

[Source: Medscape Reference: Ganglions]

[Image: Iconograms. Prof. Bockenheimer, 1913.]