MSK, Week 3 (14.1 Deeper Dissection of Hand)

Question 1

Flexor Digitorum Superficialis (FDS)

Answer 1

Origin:

1. Humero-ulnar head: medial epicondyle (common flexor origin and coronoid process)
2. Radial head (superior half of anterior border)

Insertion:
Shafts of middle phalanges of medial four digits

Innervation: 
Median Nerve (C7, C8, T1)

Action:
Flexes middle phalanges at PIP joints of middle four digits; also flexes proximal phalanges at MCP joints

Question 2

Flexor Digitorum Profundus (FDP)

Answer 2

Origin:
Proximal three quarters of medial and anterior surfaces of ulna and interosseous membrane

Insertion:
Base of distal phalanges 2-5

Innervation:
Ulnar nerve
Anterior interosseous nerve

Action:
Flexion of wrist at MCP, PIP and DIP joints at digits 2-5