Anterior Forearm

How many layers of muscles are in the anterior forearm?

There are *two main layers* — superficial and deep. Superficial = flexors from medial epicondyle deep = flexors of fingers and thumb. 💪 Mnemonic: "Flex from the front."

Which nerve mainly supplies the anterior forearm?

Mostly the *Median nerve, except 1½ muscles (Flexor carpi ulnaris + half of FDP) by the Ulnar nerve*. ⚡ Mnemonic: "Median does most, Ulnar helps."

Where do all superficial flexors originate?

From the *medial epicondyle* of the humerus via a common flexor tendon. 📍 Mnemonic: "Medial = flexor base."

Name the superficial flexor muscles of the forearm.

From lateral to medial: *Pronator teres, Flexor carpi radialis, Palmaris longus, Flexor carpi ulnaris*. 💪 Mnemonic: "Pass, Fail, Pass, Fail (PFPF)."

What is the function of Pronator teres?

*Pronates the forearm* and helps flex the elbow. Found obliquely crossing the proximal forearm. 🌀

Where is the Flexor carpi radialis?

Runs just lateral to Palmaris longus — attaches to the *base of the 2nd metacarpal*. Flexes and abducts wrist. 💪 Mnemonic: "Radial = toward thumb."

What is the Palmaris longus?

A small, thin muscle between FCR and FCU often absent in 15% of people. Tenses the palmar fascia. ✋ Mnemonic: "Palmaris = palm tension."

Where is the Flexor carpi ulnaris?

Most medial superficial muscle — attaches to *pisiform bone. Flexes and adducts wrist. Supplied by Ulnar nerve*. ⚡ Mnemonic: "Ulnar = pinky side."

Which artery runs under Flexor carpi ulnaris?

The *Ulnar artery — deep and medial, runs with the Ulnar nerve*.

What is the intermediate muscle of the forearm?

*Flexor digitorum superficialis (FDS)* — lies between superficial and deep groups. Has 4 tendons that split at the fingers. Mnemonic: "Superficialis = splits to slide."

What is the function of FDS?

Flexes the *PIP joints* of digits 2-5 and helps flex the wrist. 🖐️

Where is the Flexor digitorum profundus (FDP)?

Deep to FDS, attaches to the *distal phalanges of digits 2-5. Flexes the DIP joints*. Supplied by both Median and Ulnar nerves. ⚡ Mnemonic: "Profundus = goes deep."

What is the Flexor pollicis longus (FPL)?

Long deep muscle lateral to FDP — flexes the *thumb (pollex). Supplied by Anterior interosseous nerve*. 👍 Mnemonic: "FPL = flexes pollex."

Where is the Pronator quadratus?

Small square muscle at the *distal forearm*, deep layer, connecting radius and ulna. Initiates pronation.

Which nerve supplies Pronator quadratus?

The *Anterior interosseous nerve* (branch of Median nerve). ⚡ Mnemonic: "Quadratus = square + sup deep median."

Where is the Median nerve located in the forearm?

Runs between *FDS and FDP*, then emerges near the wrist between FDS and FCR tendons. ⚡

What does the Median nerve innervate in the forearm?

All muscles except FCU and the medial half of FDP. Controls most *flexion and pronation*. 💪

Where is the Ulnar nerve in the forearm?

Runs behind the *medial epicondyle (funny bone), then between FDP and FCU, entering wrist via Guyon's canal*.

What is the function of the Ulnar nerve in the forearm?

Supplies *Flexor carpi ulnaris* and medial FDP continues to supply intrinsic hand muscles. ⚡

Where is the Radial artery located?

Runs along the *lateral side of the forearm, deep to brachioradialis. Ends in the deep palmar arch*. Mnemonic: "Radial = thumb road."

Where is the Ulnar artery located?

Runs along the *medial side with the Ulnar nerve → ends in the superficial palmar arch*. Mnemonic: "Ulnar = pinky road."

What is the common interosseous artery?

A short branch from the Ulnar artery dividing into *anterior and posterior interosseous arteries* between the radius and ulna.

What is the Anterior interosseous nerve?

Branch of *Median nerve*, running on the interosseous membrane — supplies FPL, FDP (lateral half), and Pronator quadratus. ⚡ Mnemonic: "AIN = deep Median."

What does the superficial flexor layer look like on Anatomage?

Four long muscles from medial epicondyle → running down in a fan-like pattern. FDS is slightly deeper and broad. 🎯

What does the deep flexor layer look like on Anatomage?

Compact group near bones with tendons leading to fingers and thumb — FDP (medial), FPL (lateral), PQ (distal).

How to find the Median nerve on Anatomage?

Look for a bright yellow strand between *FDS and FDP, medial to the Brachial artery* near the elbow. ⚡

How to find the Ulnar artery and nerve?

Medial forearm: both travel together under *FCU* — artery red, nerve yellow. Mnemonic: "Ulnar = red & yellow twins." 🎯

How to remember FDS vs FDP functions?

*FDS = Superficial = middle joint (PIP), FDP = Deep = distal joint (DIP)*. ✋ Mnemonic: "Super → mid, Profund → tip."