Flexor Carpi Radialis

Original Editor - Rania Nasr Top Contributors -

Description[edit | edit source]

The flexor carpi radialis muscle is a long, superficial muscle of the forearm that belongs to the anterior muscle group and lies in the first layer. It is a relatively thin muscle located on the anterior part of the forearm. It arises in the humerus epicondyle, close to the wrist area. It is a superficial muscle that becomes very visible as the wrist comes into flexion.

Origin[edit | edit source]

The flexor carpi radialis originates from the medial epicondyle of the humerus, passes obliquely downwards to the lateral side of the forearm.

Insertion[edit | edit source]

The flexor carpi radialis inserts at the bases of the second and third metacarpal bones.

Nerve[edit | edit source]

The innervation of this muscle is provided by the median nerve and it receives its blood supply through the radial artery. 

Artery[edit | edit source]

It receives the blood the supply via the ulnar artery.

Function[edit | edit source]

The main function of FCR is providing flexion of the wrist and assisting in abduction of the hand and wrist. The flexor carpi radialis (FCR) muscle has been suggested to act as a dynamic scaphoid stabilizer. Because the FCR tendon uses the scaphoid tuberosity as a pulley to reach its distal insertion onto the second metacarpal, it has been hypothesized that FCR muscle contraction generates a dorsally directed vector that resists the scaphoid from rotating into flexion[1].  

Clinical Relevance[edit | edit source]

Flexor tendon ruptures in the wrist are uncommon. Flexor carpi radialis (FCR) tendon rupture can occur in rheumatoid patients, following cortisone injection for Tenosynovitis, and following trauma.  Attritional FCR tendon ruptures are also seen with scaphotrapezial arthritis[2].

Assessment[edit | edit source]

Manual muscle testing helps in knowing the power of the muscle

Resources[edit | edit source]

  1. Salvà-Coll G, Garcia-Elias M, Llusá-Pérez M, Rodríguez-Baeza A. The role of the flexor carpi radialis muscle in scapholunate instability. The Journal of hand surgery. 2011 Jan 1;36(1):31-6.
  2. Van Demark RE, Helsper E, Hayes M, Hayes M, Smith VJ. Painful Pseudotendon of the Flexor Carpi Radialis Tendon: A Literature Review and Case Report. HAND. 2017 Sep;12(5):NP78-83.