Hardly any other muscle group has so many small intricate complexes as those of the thumb and fingers and causes such a headache to medical students. And yet, the muscles and their functions can be very easily remembered on the basis of their denominations and the majority of them is innervated by the deep branch. It is, therefore, advisable for aspiring doctors to study with the help of mnemonics in order to be able to go relaxed into their next exam.
Are you more of a visual learner? Check out our online video lectures and start your anatomy course now for free!
Hands and Fingers

Image : “The front and back of a human right hand” by Evan-Amos. License: CC BY-SA 3.0

diese abbildung zeigt die muskeln die die hand bewegen

Image: “Titel” by philschatz. License: CC BY 4.0

Many of the muscles that move the hand and fingers are reviewed in the Anatomy of the Upper Limb – Muscles of the Arm article.

The other muscles of the hand are divided into 3 groups: the intrinsics, the thenars, and the hypothenars.

Lumbricals

Muscles Origin Insertion Nerve supply Function
Lumbricals (I-II) Lateral two tendons of FDP (unipennate) Lateral surfaces of extensor expansions of digits  2—5 Median nerve (T1) Flex metacarpophalangeal and extend interphalangeal joints of digits 2—5
Lumbricals (III-IV) Medial two tendons of FDP (bipennate) Deep branch of ulnar nerve (T1)

The lumbricals are four narrow muscle bellies which have no direct bony anchoring. They also stabilize the metacarpophalangeal joints and prevent an ulnar deviation.

Interossei Muscles

Muscle Origin Insertion Nerve supply Function
Dorsal interossei Dorsal sides of all metacarpals (bipennate) Base of proximal phalanges and extensor expansions (digits 2—4, dorsal; digits 2, 4 and 5, palmar) Deep branch of ulnar nerve (T1) Abduct digits 2—4 away from axial line
Palmar interossei Palmar sides of metacarpals 2, 4 and 5 Adduct digits 2, 4 and 5 toward axial line

The radial artery passes through between the two heads of the dorsal interosseous muscle I. There are three palmar interossei muscles and they are one-headed and lie between the metacarpal bones.

Thenar Muscles

Muscles Origin Insertion Nerve supply Function
Opponens policis Flexor retinaculum and tubercles of scaphoid and trapezium Lateral side of the first metacarpal Recurrent branch of median nerve (C8) Oppose thumb
Abductor pollicis brevis Lateral side of proximal phalanx of digit 1 Abducts thumb; supports the opposition
Flexor pollicis brevis Flexes thumb
Adductor pollicis  Oblique head: Base of second and third metacarpals and capitate
Transverse head: anterior surface of the third matacarpal		 Medial side of proximal phalanx of thumb Deep branch of ulnar nerve (C8) Adducts thumb

Hypothenar Muscles

Muscles Origin Insertion Nerve supply Function
Palmaris brevis Transverse carpal ligament and palmar aponeurosis Ulnar palm Ulnar nerve Wrinkles the skin of the medial palm
Abductor digiti minimi Pisiform Medial side of proximal phalanx of the fifth digit Deep branch of ulnar nerve (T1) Abducts the fifth digit
Flexor digiti minimi brevis Hook of hamate and flexor retinaculum Flexes proximal phalanx of the fifth digit
Opponens digiti minimi Medial border of the fifth metacarpal Rotates and draws anteriorly fifth metacarpal

Review Questions

The solutions can be found below the references.

1. Which of the following structures does not serve as the origin of the extensor digitorum muscle?

  1. Lateral epicondyle humeri
  2. Radial collateral ligament
  3. Os hamatum
  4. Annular ligament of the radius
  5. Antebrachial fascia

2. Which of the following muscles does not belong to the group of thenar muscles?

  1. Abductor pollicis longus muscle
  2. Flexor pollicis brevis muscle
  3. Abductor pollicis brevis muscle
  4. Adductor pollicis muscle
  5. Opponens pollicis muscle

3. Which of the following muscles passes through the 3rd tendon compartment?

  1. Extensor pollicis longus muscle
  2. Extensor pollicis brevis muscle
  3. Abductor pollicis longus muscle
  4. Abductor pollicis brevis muscle
  5. Adductor pollicis muscle
Do you want to learn even more?
Start now with 1,000+ free video lectures
given by award-winning educators!
Yes, let's get started!
No, thanks!
References plus_icon

Bayes, M. C. (2013). Hand and Fingers. Basics of Musculoskeletal Ultrasound,29-34. doi:10.1007/978-1-4614-3215-9_6.

Bell, C. (n.d.). Of the muscles of the arm and hand—Their vital action—Their mechanical adaptation to the motions of the hand and fingers—Form of the human hand. The Hand: Its Mechanism and Vital Endowments, as Evincing Design (7th Ed. Rev.).,81-93. doi:10.1037/12269-004.

Boscheinen-Morrin, J., & Conolly, W. B. (2001). The hand: Fundamentals of therapy. Oxford: Butterworth-Heinemann.

Rate this article
1 Star2 Stars3 Stars4 Stars5 Stars (Votes: 11, average: 4.36)
Loading...

About the Lecturio Medical Online Library

Our medical articles are the result of the hard work of our editorial board and our professional authors. Strict editorial standards and an effective quality management system help us to ensure the validity and high relevance of all content. Read more about the editorial team, authors, and our work processes.

Recommended for you

The Lungs — Anatomy and Pathology
The main task of the lung is the oxygenation of the blood and the elimination of carbon dioxide. Diseases of the lung are common and seen in every age group. Anatomic knowl... August 17, 2015 Lecturio read more
Human Lymphoid Organs
The lymphoid organs, including thymus, spleen, lymph nodes and tonsils are part of the Lymphatic System. The lymphatic system serves a purpose in immune defense. Understand... September 28, 2015 Lecturio read more

Leave a Reply

Register to leave a comment and get access to everything Lecturio offers!

Free accounts include:

  • 1,000+ free medical videos
  • 2,000+ free recall questions
  • iOS/Android App
  • Much more
REGISTER HERE

Already registered? Login.

Leave a Reply

Your email address will not be published. Required fields are marked *