Musculus flexor sublimis digitorum, commonly referred to as the flexor digitorum superficialis muscle, is a deep muscle located in the anterior compartment of the forearm. It plays a significant role in flexing the fingers.
This muscle arises from two distinct heads. The humeroulnar head originates from the medial epicondyle of the humerus, while the radial head arises from the anterior surface of the radius. Both heads fuse together to form a common muscle belly, which extends down the forearm.
The muscle belly of the flexor digitorum superficialis gives rise to four long tendons. These tendons traverse through the carpal tunnel and extend into the palm of the hand. At the level of the middle phalanges, each tendon splits into two parts, forming a Y-shaped arrangement. Each split tendon then inserts onto the base of the distal phalanx of one of the four fingers (excluding the thumb).
The primary function of the flexor digitorum superficialis is to flex the middle and proximal phalanges of the fingers, allowing for gripping and grasping. It is activated during activities such as gripping objects, typing, and writing.
In summary, the musculus flexor sublimis digitorum, or flexor digitorum superficialis, is a deep forearm muscle responsible for flexing the fingers. It arises from the humerus and radius, merges into a common belly, and gives rise to four tendons that insert in a Y-shaped manner onto the base of the distal phalanges of the four fingers. Its main function is to flex the middle and proximal phalanges, aiding in various manual activities.
