- Anatomy:
- origin:
- long head: supraglenoid tuberosity of the scapula
- short head: apex of coracoid process of scapula;
- synergists: brachialis, brachioradialis, supinator;
- innervation: musculocutaneous, C5 > C6;
- insertion:
- bicipital tuberosity of the radius and lacertus fibrosis;
- inserts on ulnar side of the lesser tuberosity, rather than as a cylinder on the center of the tuberosity;
- lacertus fibrosus typically originates from the distal short head of the biceps tendon
- references:
- The anatomy of the bicipital tuberosity and distal biceps tendon.
- Distal Biceps Tendon Anatomy: A Cadaveric Study.
- action:
- flexes and supinates the forearm at the elbow;
- reversed origin insertion action: both hands of biceps brachi are active during flexion of arm at shoulder joint, with the long head being more active;
- long head of biceps:
- see: biceps tendonitis / tendonopathy / proximal biceps tendon rupture:
- attaches to the supraglenoid tubercle of glenoid & has stabilizing and depressing action on humeral head;
- it can act as a tether and block closed reductions of proximal humerus;
- it is a useful landmark from which the rotator interval can be identified so that bone fragments are properly identified & rotator cuff are preserved;
- references:
- The role of the long head of the biceps brachii in superior stability of the glenohumeral joint.
- The Transverse Humeral Ligament. A Separate Anatomical Structure or a Continuation of the Osseous Attachment of the Rotator Cuff?
- Subluxations and dislocations of the tendon of the long head of the biceps.
- Pathologic Conditions:
- biceps tendonitis / tendonopathy :
- distal biceps tendon rupture:
- proximal biceps tendon rupture:
- erb's palsy :
- persistent absence of biceps muscle function at age 6 months in pts w/ C5-6 brachial plexus palsy from birth has been shown to correlate
w/ a poor prognosis for functional recovery;
- early brachial plexus exploration & nerve grafting will improve f(x)
Traumatic closed transection of the biceps brachi in the military parachutist.
Rupture through the short head of the biceps muscle belly. A case report.
A technique for maximizing biceps recovery in brachial plexus reconstruction.