- Anterior Portal:
- anterior portal is usually used for introduction of instruments;
- this portal is placed under arthroscopic visualization from the posterior portal;
- the needle is placed halfway between the AC joint and the lateral aspect of the coracoid;
- this portal pierces the anterior fibers of the deltoid and enters joint in interval between the
subscapularis &
supraspinatus;
- the needle should be directed into the anterior triangle formed by the labrum (medial border), biceps tendon
(superior border), and subscapularis (inferior border);
- some surgeons, place the needle more laterally, between the AC joint and the lateral acromial border;
- due to the thickness of the anterior soft tissues, consider use of a disposable sheath to
facilitate passage of instruments;
- this sheath is usually 4.5 mm w/ a side port for inflow;
- when this portal is switched into the subacromial space, it often passes directly thru the CA ligament;
- at the site of the anterior portal, the
musculocutaneous nerve may be injured by medial portal placement;
Arthroscopy of the shoulder: technique and normal anatomy.
JR Andrews et al.
Am J. Sports Med. Vol 12: p 1-7, 1984.
A Comparison of Risk Between the Lateral Decubitus and the Beach-Chair Position When Establishing an Anteroinferior Shoulder Portal: A Cadaveric Study.