Hand- Thenar and Adductor Hand Muscles

Question 1

Where do the muscles of the thenar and adductor compartments act on?

Answer 1

Digit 1- thumb

Question 2

Muscles of the thenar compartment

Answer 2

Opponens pollicis
Flexor pollicis brevis
Adductor pollicis brevis

Question 3

Muscles of the adductor compartment

Answer 3

Adductor pollicis

Question 4

Opponens pollicis

Answer 4

• Inserts on the lateral side of the first metacarpal

* Provides thumb opposition.

Question 5

Flexor pollicis brevis

Answer 5

• Inserts on base of proximal phalanx of the thumb

* Flexes the thumb.

Question 6

Abductor pollicis brevis

Answer 6

• In addition to arising from the flexor retinaculum and trapezium, also originates on the scaphoid.
• Inserts on the lateral side of the base of the proximal phalanx,
• Abducts the thumb away from the plane of the palm.
• Abductor pollicis brevis also assists opponens pollicis in the early stages of opposition.

Question 7

Adductor pollicis

Answer 7

which has two heads:

• Oblique head originates on the bases of the 2nd and 3rd metacarpals and the capitate
• Oblique head inserts on the medial side of the base of the proximal phalanx of the thumb;
• Transverse head originates on the anterior surface of the third metacarpal;
• Transverse head inserts with the oblique head on digit 1.
• Together, the oblique and transverse heads adduct the thumb.