4. Flexor Digitorum Superficialis
Origin:
- Humeroulnar head: Medial epicondyle of the humerus and coronoid process of ulna
- Radial head: Proximal half of the anterior radius
Insertion: Sides of the middle phalanges of D2-5
Action: Flexes the fingers (specifically the proximal interphalangeal joint
Innervation: Median nerve (C7/8/T1)

Needling
Position: Supine or sitting with arm supinated
Palpation: Palpate the anterior forearm and resist finger flexion
Technique: Needle perpendicular to this muscle using the ulna as a bony backdrop if needed
Caution: Low

Video 11.4 Needling flexor digitorum superficialis, original video by Nadine Crocker, CC BY-NC 4.0.