We routinely perform a thorough physical examination of the cervical spine and upper extremity in the patient with shoulder pain. We assess atrophy of the shoulder girdle, active and passive range of motion, strength, neurovascular status, and impingement signs. Proximal rupture of the tendon of the long head of the biceps is often associated with chronic cuff tendonitis and degeneration. Patients with symptomatic cuff tears have difficulty initiating abduction and present with altered scapulothoracic rhythm. More specifically, a “shrug sign” is present during arm elevation, demonstrated by increased scapulothoracic motion and decreased glenohumeral motion. With the forearm fully pronated, weakness of shoulder elevation indicates a tear in the supraspinatus. Weakness of the external rotators indicates involvement of the infraspinatus. In the largest tears, the patient may not be able to maintain the arm that is passively externally rotated. Lesser degrees of external rotation weakness may be manifest by a “lag” between the amount of passive and active external rotation. Although patients with a massive tear may exhibit full active elevation, strength testing frequently reveals marked weakness. We use the lift-off test and the belly press test to assess subscapularis function (8, 9). Again, glenohumeral instability can be the cause of the impingement and cuff tendonitis in young overhead athletes (2). A careful examination for anterior, posterior, and multidirectional instabilities should be performed.

In patients over 40 years old, we obtain routine radiographs of the affected shoulder to assess the glenohumeral joint, acromion, and acromioclavicular (AC) joint. These include anteroposterior (AP) views in internal and
external rotation, an axillary view, and a supraspinatus outlet view. A high-riding humeral head with a narrowed subacromial space suggests a large or massive rotator cuff tear. Calcific tendonitis may be readily apparent on the AP view (Fig. 1-1A), and whether present on internal rotation or external rotation view can help to localize the calcification to supraspinatus or infraspinatus tendon. A curved or beaked anterior acromion, as seen on the outlet view, is often associated with impingement (Fig. 1-1B and C). An axillary view may show an os acromiale. Osteophytes secondary to arthritis of the AC joint can contribute to impingement and cuff tendonitis. In patients under 40 years old, we routinely obtain AP, West Point axillary, and Stryker notch views to better visualize the glenoid rim and to detect Hill-Sachs lesions associated with instability.

When a rotator cuff tear is suspected, a variety of imaging studies may be performed to confirm the diagnosis. Ultrasonography has emerged as a useful tool because of its ability to obtain dynamic images. However, the utility of ultrasound depends heavily on the experience of the radiologist. At our institution, magnetic resonance imaging (MRI) is the preferred imaging modality. MRI combines accuracy in detecting full-thickness rotator cuff tears with comprehensive imaging of the shoulder joint (Fig. 1-2). Furthermore, the MRI scan has the distinct advantage of being able to reveal the size of the tear, the extent of retraction, and the quality of the remaining tissue. Fatty infiltration of the cuff musculature with retraction on MRI examination indicates a poor prognosis (Fig. 1-3). Knowing this preoperatively is important as it may alter the operative plan. Some institutions utilize intra-articular gadolinium to improve diagnostic sensitivity; however, it is not routinely used at our institution. The abduction external rotation (ABER) view for MRI of the shoulder has become increasingly popular, as it has been shown to increase the sensitivity and inter- and intraobserver agreement for detecting partial-thickness tears of the rotator cuff (10), particularly in the throwing athlete when longitudinal tears of the infraspinatus are more easily missed on standard MRI.

In addition to basic arthroscopic instruments, we use an inflow pump for shoulder arthroscopy (Arthrotek, Biomet, Warsaw, IN or Oratec, Oratec Interventions Inc., Menlo Park, CA). We typically use a 5.5-mm full-radius resector for subacromial decompression. An arthroscopic burr is useful when removing hard bone. We prefer using a tissue ablator (Arthrocare Corp., Sunnyvale, CA) for soft-tissue removal and coagulation.
If a rotator cuff repair is anticipated, we prepare instruments designed for suturing the cuff back to bone. A variety of tacks, staples, and suture anchors are available for this purpose, but we prefer using a suture repair.

Regional anesthesia for shoulder procedures is advantageous because it provides excellent postoperative analgesia without the use of intravenous narcotics. Most patients will require only oral analgesics postoperatively and can be discharged from the hospital on the day of surgery. We prefer to place patients in the beach-chair position. It avoids the potential neural complications that may occur when a patient is in the lateral decubitus position with the arm in traction. It also facilitates freedom to manipulate the humerus during intra-articular examination. Furthermore, we find it easier to convert the arthroscopic procedure to a miniarthrotomy from this position if necessary.

To achieve beach-chair positioning, lower the foot of the table and flex it 20 degrees at the waist after inducing anesthesia. Raise the back of the table so that the patient’s torso is positioned 70 degrees from the horizontal plane. Rotate the upper body roughly 20 degrees so that the operative shoulder is lifted away from the table. Recess the beanbag beneath the operative shoulder so that there is access to the medial aspect of the scapula. After deflating the beanbag, move the patient and beanbag toward the operative edge of the table (Fig. 1-4). Alternatively, a shoulder-specific table with a removable back component may be used to enhance visualization.