Flexor Carpi Radialis

  • Origin: Humerus (medial epicondyle via common flexor tendon)
    Antebrachial fascia
    Intermuscular septum
  • Insertion: 2nd and 3rd metacarpals (base, palmar surface) and trapezial ridge
  • Innervation: Cervical root(s): C6-C7
    Nerve: median nerve
  • At distal volar wrist crease the PCBMN will be in the subcutaneous tissues just ulnar to the FCR tendon.
Diagrams & Photos
  • The flexor carpi radials (FCR) tendon is one of the three muscles in the superficial compartment of the volar forearm.
    The flexor carpi radials (FCR) tendon is one of the three muscles in the superficial compartment of the volar forearm.
  • The FCR tendon is seen in the radial part of section 9. Also shown is the FCU tendon, the 4 FDS tendons, the palmaris long (PL) tendon and the radial artery at the tip of the scissor.
    The FCR tendon is seen in the radial part of section 9. Also shown is the FCU tendon, the 4 FDS tendons, the palmaris long (PL) tendon and the radial artery at the tip of the scissor.
Key Points
  • The FCR tendon does not go through the carpal tunnel but does pass through a separate fibro-osseous tunnel under the trapezial ridge on its way to insert inti the volar base of the second metacarpal.
  • When mobilizing the FCR tendon to expose the volar distal radius, be aware of the proximity of the FCR tendon to the radial artery, palmar cutaneous branch of the median nerve, and the dorsal radial sensory nerve.
  • Half or all the FCR tendon is sometimes used for reconstructing the ulnar collateral (volar beak) ligament on the thumb CMC joint ligament hyperlaxity or after trapezial excision for thumb CMC OA.
Anatomy References
Anatomic Abbreviations
Hand Surgery Resource Anatomy Diagnostic Guide (Chapter)