Triceps Brachii   

- origin:
         lateral head:  superior 1/2 of post. lat. surface of humerus;
         long head:     infraglenoid tuberosity of scapula;
         medial head:
             - inferior 2/3 on posterior surface of the humerus, beginning at the spiral groove;
             - medial head surrounds the radial nerve in the spiral groove;

- insertion: supraposterior surface of the olecranon process of the ulna and deep fascia of the forearm;
- action: extends forearm at the elbow. Longe head aids in adduction and extension of the arm at the shoulder;
- nerve supply:  Radial ,   C7  >   C6 ,   C8 ,   T1
- synergist:       Anconeus ;

- helps form triangular space  & quadrangular space:

- Injury of Triceps:
    - weakness or paralysis of triceps is usually considered of little importance, since gravity will extend elbow passively in most positions that the arm assumes;
    - however, use of the triceps is important for walking with crutches;
    - consider transfer of Brachioradialis muscle from lateral aspect of the elbow and forearm to a position posterior to lateral humeral condyle;
    - should power of the Brachialis muscle be insufficient, added power is  obtained by transferring the ECRL


Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, December 12, 2011 2:10 pm