Lecture 13

Question 1

Palmar Cutaneous Branch of Median Nerve

Answer 1

Supplies central palm, arises proximal to the flexor retinaculum (forms carpal tunnel) and passes superficial to flexor retinaculum

Question 2

Palmar Cutaneous Branch of Ulnar Nerve

Answer 2

Arises proximal to wrist, passes superficial to flexor retinaculum and palmar aponeurosis, and supplies medial side of palm

Question 3

Vascular Supply for Joints in the Hand

Answer 3

Radial and Ulnar arteries

Question 4

Carpometacarpal Joints

1. Type of Joint
2. Motion
3. Innervation

Answer 4

1. Plane synovial joints; saddle joint between metacarpus and trapezium
2. Almost none for digits 2-3, limited for 4, abduction/adduction, flexion/extension, circumduction and opposition for 5
3. Anterior interosseous branch of median nerve, posterior interosseous branch of radial nerve and dorsal/deep branches of ulnar nerve

Question 5

Metacarpophalangeal Joints

1. Type of Joint
2. Motion
3. Innervation
4. Ligaments

Answer 5

1. Condyloid synovial joint
2. Flexion/extension, abduction/adduction, some opposition at MCP 5
3. Digital nerves from ulnar and median nerves
4. Palmar ligaments (pads), collaterals (slack during extension and taut during flexion) which means fingers generally cannot be spread when these joints are flexed

Question 6

Interphalangeal Joints

1. Type of Joint
2. Motion
3. Ligaments
4. Innervation

Answer 6

1. Synovial hinge joints
2. Only flexion/extension allowed
3. Strong collaterals
4. Same as metacarpophalangeal joints

Question 7

Palmar Aponeurosis

Answer 7

Triangular layer of deep fascia located between two eminences; provides protection for superficial vessels, nerves, and tendons; anchored to skin and flexor retinaculum; splits into four slips that blend with fibrous flexor sheaths of four medial digits (2-5)

Question 8

Flexor Retinaculum

Answer 8

Laterally attaches to tubercles of scaphoid and trapezium; medially attaches to hook of hamate and pisiform

Question 9

Palmaris Brevis Muscle

1. Origin
2. Insertion
3. Function

Answer 9

1. Flexor retinaculum and palmar aponeurosis
2. Skin on medial side of palm
3. Tenses skin on palm

Question 10

Contents of Carpal Tunnel

Answer 10

Long flexor tendons of:
Flexor digitorum superficialis
Flexor digitorum profundus
Flexor pollicis longus
Median nerve

Question 11

Guyon’s Canal (Ulnar Canal)

Answer 11

Formed by groove between the pisiform and the hook of the hamate; ulnar nerve and artery pass through this canal

Question 12

Thenar Space

Answer 12

Located between the palmar side of the adductor pollicis muscle and the long flexor tendons to the index finger and the thumb

Question 13

Midpalmar Space

Answer 13

Located between metacarpals 4-5 and the long flexor tendons to digits 4-5

Question 14

Extensor Indicis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 14

1. Posterior surface of distal 1/3 of ulna and interosseous membrane
2. Extensor expansion of second finger (index finger)
3. Independent extension of 2nd finger, but also helps with extension of wrist
4. Posterior interosseous artery
5. Posterior interosseous nerve

Question 15

Thenar Eminence

1. Muscles
2. Innervation

Answer 15

1. Abductor pollicis brevis, flexor pollicis brevis, opponens pollicis
2. Recurrent branch of median nerve

Question 16

Opponens Pollicis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 16

1. Flexor retinaculum and tubercles of scaphoid and trapezium
2. Lateral side of 1st metacarpal
3. Oppose thumb and medially rotate 1st metacarpal
4. Radial Artery
5. Recurrent branch of median nerve

Question 17

Abductor Pollicis Brevis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 17

1. Flexor retinaculum and tubercles of scaphoid and trapezium
2. Lateral side of base of proximal phalanx of thumb
3. Abduct thumb; aid in opposition
4. Radial artery
5. Recurrent branch of median nerve

Question 18

Flexor Pollicis Brevis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 18

1. Flexor retinaculum and tubercles of scaphoid and trapezium
2. Lateral side of base of proximal phalanx of thumb
3. Flexes thumb
4. Radial artery
5. Recurrent branch of median nerve

Question 19

Adductor Pollicis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 19

1. Bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals
2. Medial side of base of proximal phalanx of thumb
3. Adducts thumb toward lateral border of palm
4. Radial artery
5. Deep branch of ulnar nerve

Question 20

Hypothenar Eminence

1. Muscles
2. Innervation

Answer 20

1. Abductor digiti minimi, flexor digiti minimi brevis, opponens digiti minimi
2. Ulnar nerve

Question 21

Abductor Digiti Minimi

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 21

1. Pisiform
2. Medial side of base of proximal phalanx of 5th digit
3. Abducts 5th digit, aids in flexion of 5th proximal phalanx
4. Ulnar artery
5. Deep branch of ulnar nerve

Question 22

Flexor Digiti Minimi Brevis

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 22

1. Hook of hamate and flexor retinaculum
2. Medial side of base of proximal phalanx of 5th digit
3. Flexes proximal phalanx of 5th digit
4. Ulnar artery
5. Deep branch of ulnar nerve

Question 23

Opponens Digiti Minimi

1. Proximal Attachment
2. Distal Attachment
3. Function
4. Blood Supply
5. Innervation

Answer 23

1. Hook of hamate and flexor retinaculum
2. Medial border of 5th metacarpus
3. Brings 5th metacarpal anterior and rotates it to bring it into opposition with thumb
4. Ulnar artery
5. Deep branch of ulnar nerve

Question 24

Flexor Digitorum Superficialis

Answer 24

Flexes PIP, MCP, and wrist; each tendon passes through fibrous flexor sheath; each tendon bifurcates opposite proximal phalanx; each tendon inserts on middle phalanx

Question 25

Flexor Digitorum Profundus

Answer 25

Flexes DIP, PIP, MCP; more active than superficialis; each tendon inserts on distal phalanx

Question 26

Vinculae

Answer 26

Small vascular bundles connecting palmar surface of phalanges with long flexor tendons

Question 27

Dorsal Interossei Muscles 1. Description 2. Insertion 3. Innervation

Answer 27

1. Four bipennate muscles each arising via two heads from adjacent sides of two metacarpals 2. Onto extensor expansions and radial side of proximal phalanges 2 and 3, ulnar sides of proximal phalanges 3 and 4 3. Ulnar Nerve

Question 28

Palmar Interossei Muscles 1. Description 2. Insertion 3. Innervation

Answer 28

1. Four (three) unipennate muscles (first is sometimes considered to be part of flexor pollicis brevis); supply each digit except third 2. Onto ulnar sides of proximal phalanges 1 and 2 and radial sides of proximal phalanges 4 and 5 3. Ulnar nerve

Question 29

Lumbricals

Answer 29

Four small, narrow, elongated muscles; each arises from the radial side of a flexor digitorum profundus tendon; 2 on radial side innervated by median nerve and 2 on ulnar side innervated by ulnar nerve Flexes MCP joints and extends IP joints

Question 30

First and Second Lumbricals

Answer 30

Attached to lateral 2 tendons of FDP, innervated by median nerve; blood supply from radialis indicis artery (radial artery) and superficial palmar arch (ulnar artery)

Question 31

Third and Fourth Lumbricals

Answer 31

Attached to medial 3 tendons of FDP; innervated by deep branch of ulnar nerve; blood supply from superficial palmar arch (ulnar artery) and dorsal carpal arch (ulnar and radial artery)

Question 32

Vasculature to Dorsum of Hand 1. Arterial Supply 2. Venous Drainage 3. Lymphatic Drainage

Answer 32

1. Dorsal arterial arch from radial and ulnar arteries, dorsal metacarpals, and dorsal digitals 2. Dorsal venous arch drains medially into basilic vein and drains laterally into cephalic vein 3. Medial via lymph vessels accompanying basilic vein to supratrochlear nodes to lateral axillary nodes

Question 33

Superficial Palmar Arch

Answer 33

Continuation of ulnar artery

Question 34

Deep Palmar Arch

Answer 34

Continuation of radial artery

Question 35

Mallet Finger

Answer 35

Avulsion by long extensor tendon; results in hyperflexion of DIP

Question 36

Dupuytren's Contracture

Answer 36

Progressive fibrosis of palmar aponeurosis; results in marked flexion of fingers at MP joints

Question 37

Colle's Fracture

Answer 37

Fracture in the distal end of the radius; common in those over the age of 50

Question 38

Fracture of Scaphoid

Answer 38

Most commonly fractured carpal bone; typically occurs at the waist

Question 39

Median Nerve Injury

Answer 39

Loss of thumb opposition, atrophy of thenar muscles; ape hand

Question 40

Ulnar Nerve Injury

Answer 40

Paralysis and atrophy of interossei (guttering); loss of thumb adduction; claw hand