The axillary pouch portal: a new posterior portal for visualization and instrumentation in the inferior glenohumeral recess.

Arthroscopic access to the inferior glenohumeral recess is necessary in several surgical procedures on the shoulder. Posteroinferior portals described for access to this region may pose a theoretic risk to the posterior neurovascular structures (outside-in technique) and to the articular cartilage (inside-out technique). The first author (D.N.B.) has devised a new posterior portal that permits direct linear access to the entire inferior glenohumeral recess. The portal is placed higher and more lateral compared with the previously described portals; this places it further away from the posterior neurovascular structures and facilitates linear access to the axillary pouch. The portal is created via an outside-inside technique, with a spinal needle to ascertain the correct portal site and angulation. The portal is placed at a mean distance of 20.45 +/- 4.9 mm (range, 15 to 35 mm) directly inferior to the lower border of the posterolateral acromial angle and 21.3 +/- 2 mm (range, 20 to 25 mm) lateral to the posterior viewing portal. The spinal needle or cannula is angulated medially at a mean of 30.6 degrees +/- 4.7 degrees (range, 25 degrees to 40 degrees ) in the axial plane and slightly inferiorly (mean, 2 degrees ; range, 20 degrees superiorly to 20 degrees inferiorly). Use of 30 degrees and 70 degrees arthroscopes through the axillary pouch portal facilitates visualization of the entire recess and of the humeral attachment of the inferior glenohumeral ligament complex for evaluation of humeral avulsion of the glenohumeral ligament lesions. The portal also permits instrumentation in combination with the standard posterior or anterosuperior viewing portal for removal of loose bodies, synovectomy, capsular shrinkage, capsulotomy, and anchor placement in the posteroinferior glenoid rim.