Extensor Indicis Proprius (EIP) Anatomy

Origin: Ulna (posterior surface of shaft) Interosseous membrane

Insertion: 2nd digit (via tendon of extensor digitorum into extensor hood)

Innervation: Cervical root(s): C7 and C8 Nerve: radial nerve (posterior interosseous branch)

Diagrams & Photos
  • EIP Anatomy
    EIP Anatomy
Videos
EIP Anatomy Video
Key Points
  • The EIP is ulnar and deep to the EDC in section 9 area.
  • The EIP tendon is often transferred to the thumb to reconstruct the function of a chronic EPL tendon  laceration.
Anatomy References
Anatomic Abbreviations
Hand Surgery Resource Anatomy Diagnostic Guide (Chapter)