All patients receive appropriate general anesthesia and some may elect to have an interscalene block. Patients are placed in an upright beach-chair position with the head firmly secured and the table is rotated 45 degrees allowing better access to the lateral aspect of the operative extremity. The surgical limb is then draped free after all bony prominences are padded appropriately (Figs. 40-2 and 40-3). The operative arm should be positioned in such a manner as to allow for unobstructed hyperextension and adduction. This is important in order to facilitate glenoid exposure and humeral component insertion. A skin scrub is performed with chlorhexidine gluconate and care is taken to seal off the axilla with a plastic barrier (Fig. 40-4).

An extended deltopectoral approach is used for the RSP. The deltopectoral line is marked on the skin with the proximal extent of the incision starting 5 cm medial to the acromioclavicular joint and 2 cm inferior to the clavicle. The coracoid is drawn and the line follows the anterior aspect of the deltoid to its insertion on the proximal humeral diaphysis (Fig. 40-5). An incision is made with a no. 10 scalpel and a Bovie cautery is utilized to coagulate any subcutaneous bleeding. A Gelpi self-retaining retractor helps provide tension as the superficial skin dissection proceeds through the subcutaneous fat to the deltopectoral fascia (Figs. 40-6 and 40-7). The cephalic vein may be preserved or ligated, and the subdeltoid space is entered. After a bursectomy is performed, the subdeltoid, subacromial, and subcoracoid spaces are released of all adhesions so appropriate retractors facilitate exposure. Conjoined tendon is identified and retracted medially. If intact, the coracoacromial ligament can be released. A Browne retractor is placed underneath the deltoid and the long head of the biceps is identified, a tenodesis to the upper portion of the pectoralis major tendon is performed with a 2-0 nonabsorbable suture, and the bicipital groove is exposed (Figs. 40-8, 40-9 and 40-10). Self-retaining or handheld retractors are placed beneath the deltoid laterally and conjoined tendon medially. A broad, flat retractor beneath the acromion may help bring into view the superior subscapularis, if intact, the rotator interval, and superior humeral head. In patients with an intact subscapularis, it is released off the lesser tuberosity just medial to the bicipital groove permitting a circumferential release of the capsule around the humeral neck (Fig. 40-11). Atraumatic dislocation of the humeral head is performed as the surgical assistant gently externally rotates and extends the humerus (Fig. 40-12). A circumferential release of the capsule around the humeral neck is performed along with aggressive resection of osteophytes (Figs. 40-13 and 40-14).

Next, a humeral neck cut is performed in 30 degrees of retroversion (Figs. 40-15A and B, 40-16 and 40-17). The osteotomy is performed at a level that is slightly higher than the traditional arthroplasty humeral cut (Figs. 40-17, 40-18, 40-19 and 40-20). At the most proximal portion of the osteotomy, the canal of the humerus is identified with a canal finder (Fig. 40-21). A large rongeur is used to remove some metaphyseal bone around the canal opening to facilitate easy broach insertion. The humeral canal is reamed by hand. A humeral broach is then placed into the canal and sequentially broached to the desired size and left inside in the humeral shaft (Figs. 40-22 and 40-23). The proximal humerus is then reamed using the smallest metaphyseal reamer until the superior edge is flush with bony cortex (Figs. 40-24, 40-25 and 40-26). Any remaining osteophytes and a portion of the medial calcar are resected (Fig. 40-27). The humeral broach is left in position for glenoid preparation. The final metaphyseal reamers are not used until after completion of the glenoid component insertion. This technique maintains adequate humeral bone stock to support retraction during glenoid preparation while providing a sufficient resection of the proximal humerus to facilitate glenoid exposure and visualization. The subscapularis is then tagged in its most proximal superior corner and the axillary nerve is identified and palpated (Fig. 40-28). We do not routinely dissect out the axillary nerve. A small sharp Hohmann retractor is placed on the posterior aspect of the glenoid and a Cobra retractor is placed on the anterior side of glenoid neck (Fig. 40-29).

Glenoid exposure is accomplished by using the posterior glenoid retractor to displace the proximal humerus posteriorly. A Cobra is placed anteriorly along the glenoid neck and a Hohmann retractor is positioned on the superior face of the glenoid (Figs. 40-30 and 40-31). An aggressive 360-degree subperiosteal periglenoid capsular release is performed. The inferior capsule is carefully resected while protecting the axillary nerve. At this stage, excellent glenoid exposure should be achieved. A 2.5-mm drill is used to create a center hole for the glenoid baseplate. In a normal glenoid, one in which there has not been asymmetric wear, the location of the hole is at the center of the glenoid. When looking at the glenoid, place the drill perpendicular to the glenoid face and tilt the handle of the drill 10 to 15 degrees inferiorly (Figs. 40-32 and 40-33). This position allows preferential reaming of the inferior aspect of the glenoid; consequently, if reamed correctly, more inferior than superior bone is reamed on the glenoid. After drilling is complete, a 6.5-mm tap is used and left in place to serve as a guide for the placement of the cannulated glenoid reamers. Sequential cannulated convex reamers are used to prepare for baseplate insertion (Figs. 40-34, 40-35 and 40-36). The fixed angle hydroxyapatite-coated glenoid baseplate is then screwed into place with secure purchase. Typically, four 5.0-mm peripheral locking screws are inserted into the baseplate with the use of a locking guide (Figs. 40-37 and 40-38). If the bone is insufficient along the locked screw pathway, an option
is present to use 3.5-mm nonlocking cortical screws that can be angled eccentrically to reach better bone stock. There are multiple glenosphere options (32 mm neutral, 32-4 mm, 36 mm neutral, 36-4 mm, 40 mm neutral, 40 – 4 mm, 44 + 8 mm) from which the ideal size may be selected (Fig. 40-39). Factors such as patient size, degree of soft-tissue contracture, quality of glenoid bone, and the expected degree of instability are considerations in the selection process of the optimal glenosphere size. The glenosphere is placed on the baseplate via a Morse taper. A retaining screw is then placed into the central hole of the glenosphere to augment the Morse taper attachment to the baseplate (Figs. 40-40 and 40-41).