#epitrochleoanconeus muscle

[werewolfbarista]

Extra muscles?????? If you don't mind me asking, how does that even work, and what would be the benefit to removing them?

ive got a mutation that gives me extra accessory (see: useless) muscles in my elbows! they are connected to muscles on both sides, which means they serve no purpose <3 muscles need to be attached to bone on at least one side to actually, y'know, do stuff

it's called the epitrochleoanconeus muscle (pictures below from link)

because of its positioning over the ulnar nerve, im highly susceptible to nerve damage (particularly in my right arm, since im right handed) and i have to be really careful with what i do lest i suffer The Effects

unfortunately i can't actually get them removed because, while they r causing problems Every Day Of My Life, they're also the only things keeping my ulnar nerves from slipping out of place and getting pinched (i can actually feel my nerves moving whenever i extend my arm!)

i had surgery on my right arm back in 2020 to segment the muscle such that whenever i use my arm the muscle splays out when it's inflamed instead of just bearing down fully on the nerve. so good news is my arm isn't technically as bad as it used to be, but nerves heal extremely slowly so the damage to my arms is like, cumulative cause a few days off from work isn't really enough for them to be Fine whenever something as small as playing games on my phone can hurt me

[sciencenewsforstudents]

Human embryos are more muscle-bound than adult humans, new microscope images cataloging early development show.

For instance, at seven weeks of gestation, embryonic hands have about 30 muscles. Adults have about 19. Many of the muscles are lost, and some fuse with others, adopting the adult arrangement by 13 weeks of gestation, researchers report October 1 in Development.

Muscles in the feet, legs, trunk, arms and head also appear and disappear during development, researchers discovered after analyzing detailed 3-D images of human embryos and fetuses up to 13 weeks of gestation.

These appearing and disappearing, or atavistic, muscles are remnants of evolution, says biologist Rui Diogo of Howard University in Washington, D.C. Such atavistic muscles are built as a base from which to start paring down to the final set of muscles that people are born with, he says. “Losing and specializing, that’s what happens in human evolution.”

Other animals have kept some of those muscles. Adult chimpanzees and human embryos have epitrochleoanconeus muscles in their forearms, but most adult humans don’t. Human’s mammalian ancestors also lost dorsometacarpales muscles from the back of the hand about 250 million years ago as mammals and reptiles split on the evolutionary tree. Lizards still have those muscles, and they appear in human embryos, but then are lost or fuse with other muscles during development and aren’t found in most adults.

Sometimes, people retain some of the usually lost muscles, resulting in harmless anatomical variations. For example, about 13 percent of people in one study had epitrochleoanconeus muscles in their forearms.