The Delto-pectoral approach is the workhorse of the shoulder surgeon, but surprisingly the common variants of the cephalic vein and deltoid artery have not been documented. The vascular anatomy encountered during one hundred primary elective delto-pectoral approaches was documented and common variants described. Two common variants are described. A type I (71%), whereby the deltoid artery crosses the interval and inserts directly in to the deltoid musculature. In this variant the surgeon is unlikely to encounter any vessels crossing the interval apart from the deltoid artery itself. In a type II pattern (21%) the deltoid artery runs parallel to the cephalic vein on the deltoid surface and is highly likely to give off medial branches (95%) that cross the interval, as well as medial tributaries to the cephalic vein (38%). Knowledge of the two common variants will aid the surgeon when dissecting the delto-pectoral approach and highlights that these vessels crossing the interval are likely to be arterial, rather than venous. This study allows the surgeon to recognize these variations and reproduce bloodless, safe and efficient surgery

The standard approach is through the deltopectoral interval. Among patients with prior incisions, one makes every effort to either utilise the old incision or to incorporate it into a longer incision that will allow one to approach the deltopectoral interval and retract the deltoid laterally. The deltopectoral interval is most easily developed just distal to the clavicle, where there is a natural infraclavicular triangle of fat that separates the deltoid and pectoralis major muscles even in very scarred or stiff shoulders. Typically, the deltoid is retracted laterally leaving the cephalic vein on the medial aspect of the exposure. The anterior border of the deltoid is mobilised from the clavicle to its insertion on the humerus. The anterior portion of the deltoid insertion together with the more distal periosteum of the humerus may be elevated slightly. The next step is to identify the plane between the conjoined tendon group and the subscapularis muscle. Dissection in this area must be done very carefully due to the close proximity of the neurovascular group, the axillary nerve, and the musculocutaneous nerve. Scar is then released from around the base of the coracoid. The subacromial space is freed of scar and the shoulder is examined for range of motion. Particularly among patients with prior rotator cuff surgery, there may be severe scarring in the subacromial space. Internal rotation of the arm with dissection between the remaining rotator cuff and deltoid is critical to develop this plane. If external rotation is less than 30 degrees, one can consider incising the subscapularis off bone rather than through its tendinous substance. For every 1 cm that the subscapularis is advanced medially, one gains approximately 20 to 30 degrees of external rotation. The rotator interval between the subscapularis and supraspinatus is then incised. This release is then continued inferiorly to incise the inferior shoulder capsule from the neck of the humerus. This is performed by proceeding from anterior to posterior with progressive external rotation of the humerus staying directly on the bone with electrocautery and great care to protect the axillary nerve. The key for glenoid exposure as well as improvement in motion is deltoid mobilization, a large inferior capsular release, aggressive humeral head cut and osteophyte removal