The purpose of this study was to examine the neurovascular structures at risk during
placement of glenohumeral arthroscopy portals using an outside–in technique.
Type of study
Anatomic cadaveric study.
Five fresh-frozen cadaveric specimens were used in this study. Each shoulder was mounted
on a custom-designed apparatus allowing shoulder arthroscopy in a lateral decubitus
position. The following portals were established using an outside–in technique and
marked using an 18-gauge spinal needle: posterior, posterolateral, anterior, 5-o’clock,
anterosuperolateral, and Port of Wilmington. Each specimen was carefully dissected
after the procedure, and the distance from each portal site to the adjacent relevant
neurovascular structures (axillary nerve, musculocutaneous nerve, lateral cord of
the brachial plexus, cephalic vein, and axillary artery) was measured using a precision
Except for the cephalic vein, all of the neurovascular structures were more than 20
mm away from all the portals evaluated. When creating either an anterior portal or
a 5-o’clock position portal, the mean distance from the portal to the cephalic vein
was 18.8 mm and 9.8 mm, respectively. In one anterior portal, a direct injury to the
cephalic vein occurred.
Our study suggests that shoulder arthroscopy portals placed in an outside–in fashion
are unlikely to produce neurologic injury. However, the cephalic vein is at risk during
placement of an anterior or 5-o’clock position portal, although probably with minimal
subsequent patient morbidity. Placing portals in an outside–in fashion guarantees
the correct angle of approach, with minimal risk to adjacent neurologic structures.
This study shows the safety of standard and accessory glenohumeral arthroscopy portals.