Muscles of a brush

The muscles of the hand are divided into 3 groups:

1. muscles of the thumb (lateral group) forming in the lateral region of the palm a well-defined elevation of the thumb (tenar, thenar);
2. muscles of the little finger (medial group) forming in the medial region of the palm elevation of the little finger (hypotenar, hipothenar);
3. the middle group of muscles of the hand located between the two groups of muscles, and also on the rear of the hand.

[1], [2]

Muscle of the thumb

The short muscle that removes the thumb of the hand (m.abductor pollicis brevis), flat, is superficially located. It begins with muscle tufts on the lateral part of the flexor retainer, scaphoid tubercle and trapezoid bone Attached to the radial side of the proximal phalanx of the thumb and to the lateral edge of the tendon of the long extensor of the thumb of the hand.

Function: draws the thumb of the brush.

Innervation: the median nerve (CV-ThI).

Blood supply: the superficial palmar branch of the radial artery.

The muscle that opposes the thumb of the hand (m.opponens pollicis), partially covered by the previous muscle, is fused to the short flexor of the thumb of the wrist, located medially from the nes. Begins on the flexor holder and on the trapezoid bone. It is attached to the radial margin and the anterior surface of the first metacarpal bone.

Function: Opposes the thumb of the hand to the little finger and all the other fingers of the brush.

Innervation: the median nerve (CV-ThI).

Blood supply: superficial palmar branch of the radial artery, deep palmar arc.

The short flexor of the thumb of the hand (m flexor pollicis bnivis) is partially covered by a short muscle that removes the thumb of the hand. The surface head (caput superficiale) begins on the flexor holder, the deep head (caput profundum) on the trapezoid bone and trapezoid bone, on the 11th metacarpal bone. It is attached to the proximal phalange of the thumb of the hand (there is a sesamoid bone in the thickness of the tendon).

Function: bends the proximal phalanx of the thumb of the hand and the finger as a whole; participates in bringing this finger.

Innervation: the median nerve (CV-ThI), ulnar nerve (СVIII-ThI).

Blood supply: superficial palmar branch of the radial artery, deep palmar arc. 

The muscle that leads the thumb of the hand (m.adductor pollicis) is located under the tendons of the long flexors of the fingers (superficial and deep) and under the wormlike muscles. Has two heads - oblique and transverse. The oblique head (caput breve) begins on the cephalic bone and the bases of the II and III metacarpal bones.

The transverse head (caput transversum) begins on the palmar surface of the third metacarpal bone. The muscle is attached by a common tendon, in which there is a sesamoid bone, to the proximal phalange of the thumb of the hand.

Function: brings the thumb of the brush to the index finger, participates in flexing the thumb of the brush.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: superficial and deep palmar arcs.

Muscles of an eminence of a little finger

The short palmar muscle (m.palmaris brevis) is a rudimentary cutaneous muscle, represented by mild muscle beams in the subcutaneous base of the pinky of the little finger. The tufts of this muscle begin on the flexor retainer, attach to the skin of the medial edge of the hand.

Function: Slight creases appear on the skin of the little finger.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: ulnar artery.

The muscle that removes the little finger (m.abductor digiti minimi) is superficially located. It starts on the pea bones and the tendon of the elbow flexor of the wrist. It is attached to the medial side of the proximal phalanx of the little finger.

Function: draws the little finger.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: a deep branch of the ulnar artery.

The muscle, opposing the little finger (m.opponens digiti minimi), begins with tendon bundles on the flexor retainer and the hook of the hook-shaped bone. It is located under the muscle that removes the little finger. It is attached to the medial margin and the anterior surface of the metacarpal bone.

Function: Opposites the little finger to the thumb of the hand.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: a deep palmar branch of the ulnar artery.

The short flexor of the little finger (m.flexor digiti minimi brevis) begins with tendon tufts on the flexor retainer and the hook of the hook-shaped bone. It is attached to the proximal phalanx of the little finger.

Function: flexes the little finger.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: a deep palmar branch of the ulnar artery.

Average group of muscles of the hand

The vermiform muscles (mm.lumbricales) are thin, cylindrical in shape, in the number 4 they lie directly under the palmar aponeurosis. Begins on the tendons of the deep flexor of the fingers. The first and second vermiform muscles begin on the radial edge of the tendons that go to the index and middle fingers. The third muscle begins on the sides of the tendon facing the third and fourth fingers facing each other, the fourth on the facing edges of the tendons that approach the fourth finger and little finger. Distal each worm-shaped muscle is directed to the radial side of the II-V fingers respectively and passes to the rear of the proximal phalanx. The vermiform muscles are attached to the base of the proximal phalanges along with the tendon extensions of the extensor fingers.

Function: bend the proximal phalanges and unbend the middle and distal phalanges of the II-IV fingers.

Innervation: the first and second vermiform muscles are the median nerve; the third and fourth - the ulnar nerve (CV-ThI).

Blood supply: superficial and deep palmar arcs. 

The interosseous muscles (mm.interossei) are located between the metacarpal bones, divided into two groups - the palmar and the rear.

The palmar interosseous muscles (mm.interossei palmares) in the number of three are located in the second, third and fourth interosseous spaces. Begin on the lateral surfaces of II, IV and V metacarpal bones. They are attached by thin tendons to the back side of the proximal phalanges of the II, IV and V fingers.

The first palmar interosseous muscle begins on the ulnar side of the II metacarpal bone; is attached to the base of the proximal phalange of the 2nd finger. The second and third palmar interosseous muscles begin on the radial side of IV-V metacarpal bone; attach to the back surface of the proximal phalanges IV and V fingers.

Function: bring the II, IV and V fingers to the middle (III) finger.

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: deep palmar arc.

The rear interosseous muscles (mm., Interossei dorsales) are much thicker than the palmar ones, 4. All 4 muscles occupy the intervals between the metacarpal bones. Each muscle begins with two heads on the surfaces of the IV metacarpal bone facing each other. The muscles are attached to the base of the proximal phalanges of the II-V fingers.

The tendon of the first back interosseous muscle is attached to the radial side of the proximal phalange of the index finger, the second muscle to the radial side of the proximal phalanx of the middle (III) finger. The third muscle is attached to the ulnar side of the proximal phalanx of this finger; the tendon of the fourth back interosseous muscle is attached to the ulnar side of the proximal phalanx of the fourth finger.

Function: withdraw I, II and IV fingers from the middle finger (W).

Innervation: ulnar nerve (СVIII-ThI).

Blood supply: deep palmar arc, dorsal metacarpal arteries.

[3], [4], [5]