The anterior humeral circumflex vessels and the axillary nerve. An anatomic study.

The anatomic relationship between the anterior humeral circumflex vessels and the axillary nerve was studied in 24 fresh-frozen cadaveric four-quarter shoulder specimens. Each shoulder was exposed through a standard deltopectoral incision, and the axillary nerve, anterior humeral circumflex vessels, and bicipital groove were identified. The perpendicular distance from the medial border of the bicipital groove to a point where the vessels crossed anterior to the nerve measured 2.6 +/- 0.4 cm (range, 2.1-3.6 cm). The perpendicular distance from the medial aspect of the bicipital groove to the point where the axillary nerve crossed the inferior border of the subscapularis and thus entered the quadrangular space was 3.0 +/- 0.5 cm (range, 2.1-4.4 cm). The anterior humeral circumflex vessels were easily located in all specimens, and the axillary nerve could be identified by its relationship to the vessels as described above, thus providing the operating surgeon with a consistent and reliable method of recognizing this nerve during anterior shoulder procedures. In addition, the axillary nerve was palpable in all specimens by sweeping the index finger in a medial-to-lateral direction along the inferior border of the subscapularis.