The foundation to a successful operation begins with appropriate patient positioning. The most commonly used positions for ORIF of proximal humerus fractures are beach chair and supine. Many factors contribute to the decision to use one versus the other, including surgeon familiarity, OR resources, concomitant injuries, ease of fluoroscopic imaging, anesthetic concerns, as well as the consideration for potential arthroplasty. Beach-chair positioning is often utilized by shoulder surgeons who routinely use this for elective shoulder procedures (Figure 29-2). The benefit of this position aside from familiarity is access to the entire shoulder if adjunctive or percutaneous incisions are needed as well as the ability to extend the shoulder in cases of arthroplasty or visualization of head-split fractures. Downsides of beach-chair positioning are the concerns for cerebral hypotension with the head of the patient elevated, as well as potential difficulties in the polytraumatized patient.

Another important consideration related to the patient position is the ability to obtain appropriate fluoroscopic imaging. The C-arm can be brought in from the head of the patient or from the contralateral side, depending on the type of bed, position, and image intensifier used (Figure 29-3). Regardless, as with a patient with any fracture undergoing surgery, orthogonal views are required to judge appropriate reduction and safe fixation (Figure 29-4). An AP/PA view of the proximal humerus is the primary standard view obtained most frequently during ORIF. Although a Grashey view (true AP in the plane of the scapula separating the humeral head and the glenoid) is not necessary, a true AP of the proximal humerus should be used to judge the coronal plane reduction. In a true AP of the proximal humerus, there will be maximum separation between the profile of the greater tuberosity and the articular margin of the humeral head (Figure 29-5). When getting this image, it is important to consider the retroversion of the proximal humerus relative to the distal humerus/forearm, as well as ensure that the humeral diaphysis is parallel to the receiver of the image intensifier in order to avoid flexed or extended images.

For the orthogonal view, both axillary views and scapular Y views have been described. Although the scapular Y view is insufficient to judge glenohumeral alignment, it does provide some visualization of sagittal plate alignment of the proximal humerus. More commonly, an axillary view is obtained by abducting the shoulder and rotating the C-arm 90° from the AP image. Getting this view often requires some provisional fixation to be in place to allow abduction of the shoulder. If the surgeon is inexperienced with the procedure or the setup, it is vital that the C-arm is brought in prior to prepping and draping to ensure that appropriate imaging can be obtained (Figure 29-4).

Intraoperatively, the position of the limb has significant implications for reduction and visualization. Surgical assistants may help manipulate the arm throughout the surgery, but intraoperative arm holders provide the benefit of sustained reduction without the need for extra personnel. In particular, gentle shoulder flexion and traction are useful for many cases, as is the ability to hold the arm in external rotation when fluoroscopically assessing an AP view. Multiple arm-positioning devices are available on the market currently, some using pneumatic technology and others relying on internal gears.

The two most common approaches to ORIF of proximal humerus fractures are the deltopectoral approach and the anterolateral acromial (deltoid-splitting) approach. Percutaneous and minimally invasive approaches have been described but are less commonly used for plate fixation of the proximal humerus.

The deltopectoral approach is the standard workhorse approach to the shoulder and is familiar to many surgeons for a variety of procedures, including fracture fixation, open instability surgery, and shoulder arthroplasty. It relies on the anterior internervous plane between the deltoid and the pectoralis major muscles, with the cephalic vein retracted with either muscle. The subdeltoid and subacromial space must be mobilized to allow for retractor placement deep to the deltoid and access to the lateral surface of the proximal humerus. The clavipectoral fascia lateral to the conjoint tendon is incised and the interval between the conjoint and the underlying subscapularis can be bluntly developed. The axillary nerve should be identified by visualization or palpation in this interval as it courses deep and lateral underneath the glenohumeral joint. The distal extent of the axillary nerve may also be identified, as it lies deep to the deltoid laterally. At this point, for fractures of the proximal humerus, much of the approach is done and attention can be turned to exposing and cleaning the fracture. Depending on the patient and surgeon preference, the rotator interval can be opened and the long head of the biceps tenodesed as part of the exposure. Some advocate for doing this routinely to eliminate a potential pain generator in the biceps and contributor to posttraumatic contracture in the rotator interval. The other potential benefit in doing so is some degree of access to the glenohumeral joint. If there is minor or peripheral articular involvement, this can often be seen or palpated
through the opened rotator interval. At the end of the fixation, the humeral head can also be palpated to ensure no screw prominence. If further exposure of the articular surface is required, as in a true head-splitting fracture, standard methods of subscapularis mobilization (including a tendon peel or lesser tuberosity osteotomy) can be used¹⁴ (Figure 29-6). If a lesser tuberosity fracture is part of the fracture pattern, then it can be utilized as well.