Abstract
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.
