The tailor's muscle
Sartorius · musculus sartorius
The longest muscle in the body, a strap that runs diagonally across the front of your thigh.
What it does
The sartorius runs from the front of the hip bone diagonally across the thigh to the inside of the knee. It helps bend the hip and knee and turn the thigh outwards, the movements you make to sit cross-legged.
Surprising fact
It is the longest muscle in the human body, and its name comes from the Latin for "tailor", because tailors once sat cross-legged to sew.
Why it matters
Its lower tendon joins those of gracilis and semitendinosus on the inside of the knee in a structure called the "goose's foot", a common spot for knee pain in runners.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.