Lumbricals of the hand

Information about Lumbricals of the hand

For the foot muscles, see Lumbrical muscle of the foot


The muscles of the left hand. Palmar surface. (1st lumbricalis labeled at bottom right of muscular group.)
Latinmusculi lumbricales manus
subject #126 464
Origin:flexor digitorum profundus
Insertion:extensor expansion
Artery:superficial palmar arch, common palmar digital arteries, deep palmar arch, dorsal digital artery
Nerve:deep branch of ulnar nerve, median nerve
Action:flex metacarpophalangeal joints, extend interphalangeal joints
Dorlands/Elsevier m_22/12549749
The lumbrical muscles are intrinsic muscles in the fingers that allow flexion at the metacarpophalangeal joints, while maintaining extension at the interphalangeal joints.

Structure

There are four of these small, worm-like muscles on each hand. These muscles are unusual in that they do not attach to bone. Instead they attach proximally to the tendons of flexor digitorum profundus and distally to extensor expansions on the dorsal surface (back) of the hand.

#FormOriginInsertion
firstunipennateIt originates from the lateral side of the most lateral tendon of the flexor digitorum profundus (corresponding to the index finger).It passes posteriorly along the lateral side of the index finger to insert on the extensor expansion near the metacarpophalangeal joint.
secondunipennateIt originates from the lateral side of the second most lateral tendon of the flexor digitorum (which corresponds to the middle finger).It passes posteriorly along the lateral side of the middle finger and inserts on the extensor expansion near the metacarpophalangeal joint.
thirdbipennateOne head originates on the lateral side of the flexor digitorum profundus tendon corresponding to the ring finger, while the other originates on the medial side of the tendon for the middle finger.The muscle passes posteriorly along the lateral side of the ring finger to insert on its extensor expansion.
fourthbipennateOne head originates on the lateral side of the flexor digitorum profundus tendon corresponding to the little finger, while the other originates on the medial side of the tendon for the ring finger.The muscle passes posteriorly along the lateral side of the little finger to insert on its extensor expansion.

Innervation

The first and second lumbricals (i.e. the two that are most lateral) are innervated by the median nerve. The third and fourth lumbricals (i.e. the most medial two) are innervated by the deep branch of the ulnar nerve.

Blood supply

There are four separate sources of blood supply for these muscles: the superficial palmar arch, the common palmar digital artery, the deep palmar arch, and the dorsal digital artery.

Actions

The lumbrical muscles, with the help of the interosseous muscles, simultaneously flex the metacarpophalangeal joints while extending both interphalangeal joints of the digit on which it inserts.

Other lumbricals

There are also lumbrical muscles of the foot that have a similar action, though these are of less clinical concern.

Additional images


Tendons of forefinger and vincula tendina.


External links

 •  • [ e]
Muscles of upper limbs
VERTEBRAL COLUMNtrapezius - latissimus dorsi - rhomboid major - rhomboid minor - levator scapulae
THORACIC WALLSpectoralis major - pectoralis minor - subclavius - serratus anterior
SHOULDERdeltoid - rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) - teres major
ARManterior compartment: coracobrachialis - biceps brachii - brachialis
posterior compartment: triceps brachii - anconeus
FOREARManterior compartment: super. - pronator teres - palmaris longus - flexor carpi radialis - flexor carpi ulnaris - flexor digitorum superficialis - deep - pronator quadratus - flexor digitorum profundus - flexor pollicis longus
posterior compartment: super. - mobile wad (brachioradialis, extensor carpi radialis longus and brevis) - extensor digitorum, - extensor digiti minimi - extensor carpi ulnaris - deep - supinator - anatomical snuff box (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus) - extensor indicis
HANDlateral volar - thenar (opponens pollicis, flexor pollicis brevis, abductor pollicis brevis, adductor pollicis)
medial volar - palmaris brevis - hypothenar (abductor minimi digiti, flexor digiti minimi brevis, opponens digiti minimi)
intermediate - lumbrical - dorsal interossei - palmar interossei
For the muscle of the hand, see Lumbrical muscle (hand).
The Lumbricales are four small muscles, accessory to the tendons of the Flexor digitorum longus and numbered from the medial side of the foot; they arise from these tendons, as far back as their
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Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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bold refer to the diagram at right.)

In the skull (8):
  • 1-9. cranium
  • 7. mandible
''In the middle ears (6):
  • malleus
  • incus
  • stapes
In the throat (1):
  • hyoid
In the shoulder girdle (4):
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In human anatomy, the flexor digitorum profundus is a muscle in the forearm that flexes the fingers. It is considered to be an extrinsic muscle because its action is at a different location than the main body of the muscle.
..... Click the link for more information.
bold refer to the diagram at right.)

In the skull (8):
  • 1-9. cranium
  • 7. mandible
''In the middle ears (6):
  • malleus
  • incus
  • stapes
In the throat (1):
  • hyoid
In the shoulder girdle (4):
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An extensor expansion (dorsal expansion, dorsal hood) is an anatomical term that refers to the flattened tendons (aponeurosis) of extensor muscles that run into the back of the hand.
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Arteries are muscular blood vessels that carry blood away from the heart.[1] All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.

The circulatory system is extremely important for sustaining life.
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The superficial palmar arch (superficial volar arch) is formed predominantly by the ulnar artery, with a contribution from the superficial palmar branch of the radial artery.

The arch passes across the palm in a curve with its convexity downward.
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Three common palmar digital arteries (common volar digital arteries) arise from the convexity of the arch and proceed downward on the second, third, and fourth Lumbricales.
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The deep palmar arch (deep volar arch) is an arterial network found in the palm. It is usually formed mainly from the terminal part of the radial artery, with the ulnar artery contributing via its deep palmar branch.
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Most of the dorsal metacarpal arteries arise from the dorsal carpal arch and run downward on the second, third, and fourth dorsal interossei of the hand and bifurcate into the dorsal digital arteries.
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  • Accessory nerve
  • Accessory obturator nerve
  • Alderman's nerve
  • Anococcygeal nerve
  • Ansa cervicalis
  • Anterior interosseous nerve
  • Anterior superior alveolar nerve
  • Aortic plexus
  • Auerbach's plexus
  • Auriculotemporal nerve
  • Axillary nerve

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The deep branch of the ulnar nerve, accompanied by the deep branch of the ulnar artery, passes between the abductor digiti minimi and the flexor digiti minimi brevis.
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The median nerve is a nerve that runs down the arm and forearm. It is one of the five main nerves originating from the brachial plexus.

The median nerve is formed from parts of the medial and lateral cords of the brachial plexus, and continues down the arm to enter the
..... Click the link for more information.
Kinesiology is the scientific study of the anatomy, physiology, and mechanics of body movement, especially in humans. [1] The word kinesiology is derived the Greek "kinesis" (motion) + the suffix -ology or -logy from the greek "logos" or "logia"(meaning a field of study).
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flexion is a position that is made possible by the joint angle decreasing. The skeletal (bones, cartilage, and ligaments) and muscular (muscles and tendons) systems work together to move the joint into a "flexed" position.
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The metacarpophalangeal joints (MCP) are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the first phalanges, with the exception of that of the thumb, which presents more of the characters
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Extension may refer to:
  • Extension (kinesiology), a movement of a joint in which one part of the body is moved away from another.
  • Extension (metaphysics), the property of taking up space
  • Extension (semantics), the set of things to which a property applied

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The interphalangeal articulations of hand are hinge-joints of the phalanges of the hand. There are two sets (except in the thumb):
  • "proximal interphalangeal joints" (PIP), those between the first (also called proximal) and second (intermediate) phalanges

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Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
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MUSCLE (multiple sequence comparison by log-expectation) is public domain, multiple sequence alignment software for protein and nucleotide sequences.
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A finger is a type of digit, an organ of manipulation and sensation found in the hands of humans and other primates. Normally humans have five digits on each hand (exceptions are polydactyly, hypodactyly and digit loss).
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The metacarpophalangeal joints (MCP) are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the first phalanges, with the exception of that of the thumb, which presents more of the characters
..... Click the link for more information.
The interphalangeal articulations of hand are hinge-joints of the phalanges of the hand. There are two sets (except in the thumb):
  • "proximal interphalangeal joints" (PIP), those between the first (also called proximal) and second (intermediate) phalanges

..... Click the link for more information.
In human anatomy, the flexor digitorum profundus is a muscle in the forearm that flexes the fingers. It is considered to be an extrinsic muscle because its action is at a different location than the main body of the muscle.
..... Click the link for more information.
unipennate.

External links

  • unipennate at eMedicine Dictionary
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated.
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An extensor expansion (dorsal expansion, dorsal hood) is an anatomical term that refers to the flattened tendons (aponeurosis) of extensor muscles that run into the back of the hand.
..... Click the link for more information.
The metacarpophalangeal joints (MCP) are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the first phalanges, with the exception of that of the thumb, which presents more of the characters
..... Click the link for more information.
bipennate, and an example is afforded in the Rectus femoris.

External links

  • Bipennate at eMedicine Dictionary
This article was originally based on an entry from a public domain edition of Gray's Anatomy.
..... Click the link for more information.
The median nerve is a nerve that runs down the arm and forearm. It is one of the five main nerves originating from the brachial plexus.

The median nerve is formed from parts of the medial and lateral cords of the brachial plexus, and continues down the arm to enter the
..... Click the link for more information.

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