Muscles of the Hand Flashcards
Extensor Tendon Compartment #1 (Lateral to Medial)
ABductor Pollicis Long, Extensor Pollicis Brevis
Extensor Tendon Compartment #2(Lateral to Medial)
Extensor Carpi Radialis Longus and Extensor Carpi Radialis Brevis
Extensor Tendon Compartment #3 (Lateral to Medial)
Extensor Pollicis Longus
Extensor Tendon Compartment #4 (Lateral to Medial)
Extensor Digitorum and Extensor Indicis
Extensor Tendon Compartment #5 (Lateral to Medial)
Extensor Digiti Minimi
Extensor Tendon Compartment #6 (Lateral to Medial)
Extensor Carpi Ulnaris
Muscle of the Thenar compartment
- ABductor Pollicis Brevis
- Flexor Pollicis Brevis
- Opponens Pollicis
Abductor Pollicis Brevis Origin
Flexor Retinaculum and lateral pillars of carpal tunnel (scaphoid and trapezium bones)
Abductor Pollicis Brevis Insertion
Lateral side, base of proximal phalanx and extensor hood of thumb
Abductor Pollicis Brevis Innervation
Motor recurrent branch of the Median Nerve (C8/T1)
Abductor Pollicis Brevis Action
Abduction of the thumb
Flexor Pollicis Brevis Origin
Flexor retinaculum and tubercle of the trapezium bone
Flexor Pollicis Brevis Insertion
Lateral side, base proximal phalanx; sesamoid bone at head of 1st metacarpal bone
Flexor Pollicis Brevis Innervation
Motor recurrent branch of the Median Nerve C8/T1
Flexor Pollicis Brevis Action
Flexion of thumb
Opponens Pollicis Origin
Flexor Retinaculum and tubercle of trapezium bone
Opponens Pollicis Insertion
Whole length of 1st metacarpal bone, palmar surface and lateral margin
Opponens Pollicis Innervation
Motor recurrent nerve of Median Nerve (C8-T1)
Opponens Pollicis Action
Thumb opposition (Rotates 1st MC medially and draws thumb toward center of palm)
Adductor Pollicis Origin
Oblique head: base of MC #2 and #3; Capitate bone
Transverse Head: Anterior Surface of shaft of MC #3
Adductor Pollicis Insertion
Medial side, base of proximal phalanx and extensor hood of thumb; sesamoid bone at head of 1st metacarpal
Adductor Pollicis Innervation
Deep branch of ulnar nerve (C8/T1)
Adductor Pollicis Action
Thumb Adduction
Muscles of the Hypothenar Eminence
- Abductor Digiti Minimi
- Flexor Digiti Minimi Brevis
- Opponens Digiti Minimi
Abductor Digiti Minimi Origin
Pisiform bone, tendon of Flexor Carpi Ulnars, and pisohamate ligament
Abductor Digiti Minimi Insertion
Medial side, base of proximal phalanx of little finger, DDE
Abductor Digiti Minimi Innervation
Deep branch of ulnar nerve (C8/T1)
Abductor Digiti Minimi Action
Abduction of little finger
Flexor Digiti Minimi Brevis Origin
Flexor retinaculum and hook of hamate
Flexor Digiti Minimi Brevis Insertion
Medial side, base of proximal phalanx of little finger
Flexor Digiti Minimi Brevis Innervation
Deep branch of Ulnar nerve (C8/T1)
Flexor Digiti Minimi Brevis Action
Flexion of the little finger at MP joint
Opponens Digiti Minimi Origin
Flexor retinaculum and hood of hamate
Opponens Digiti Minimi Insertion
Medial margin and palmar surface of shaft of #5 MC
Opponens Digiti Minimi Innervation
Deep branch of Ulnar Nerve (C8/T1)
Opponens Digiti Minimi Action
Draws 5th finger forward and rotates it laterally for opposition
Intrinsic muscles of the hand (not part of the Thenar and hypothenar eminence)
Adductor pollicis Palmaris Brevis Lumbricals Dorsal Interossei palmar Interossei
Palmaris Brevis Origin
Flexor retinaculum and palmar aponeurosis (medial margin)
Palmaris Brevis Insertion
Skin on medial side of palm; Blends with fascia over hypothenar eminence (both attachments are soft)
Palmaris Brevis Innervation
Superficial branch of ulnar nerve ( C8/T1)
Palmaris Brevis Action
Tenses skin over hypothenar eminence and deepens the hallow of the hand
Lumbricals Origin
Tendons of the Flexor Digitorum Profundus
- # 1/2 are unipennate muscles: Lateral (Radial) side of FDP tendons to index and middle fingers
- # 3/4 are bipennate muscles: Adjacent sides of FDP tendons to middle ring, and little finger
Lumbricals Insertion
Lateral (radial Side) of the DDE to fingers 2, 3, 4, 5
Lumbricals Innervation
#1/#2 by Median Nerve (Common Palmar digital branches) #3/4 by deep Branch of Ulnar Nerve (all C8-T1)
Lumbricals Action
MP flexion, PIP and DIP extension of fingers 2-5
Dorsal Interossei Origin (Bipennate)
Adjacent Sides of 2 MC Bones
Dorsal Interossei Insertion
Base of proximal phalanx of fingers 2,3,4 and DDE:
#1: Lateral side of index finger #2: Lateral side of middle finger #3: Medial Side of middle finger #4: medial side of ring finger
Dorsal Interossei Innervation
Deep branch of nerve (C8/T1)
Dorsal Interossei Action
Abduction of Fingers #2-4 at MP joints; MP Flexion, IP Extension via DDE and digits 2-4
Palmar/Volar Inerossei Origin
Palmar shaft surface of MC 1, 2, 4, and 5
Medial Side: #1, 2
Lateral side: #4, 5
Palmar/Volar Inerossei Insertion
Base proximal phalanx, fingers 1, 2, 4, and 5 and DDE
- Fingers 1-2 on medial Side
- Fingers 4-5 on Lateral side
Palmar/Volar Inerossei Innervation
Deep branch of ulnar nerve (C8-T1)