The surgeon must carefully examine routine anteroposterior (AP), axillary, and arch radiographs. The glenohumeral space and acromiohumeral distance are carefully evaluated on the AP view for arthritis, aseptic necrosis, and calcifications. The axillary view is routinely obtained because it tells the surgeon whether an os acromion is present. The arch view shows acromion shape and thickness. Additionally, a weight-bearing “push-up” AP view, in which upward pressure is placed on the humerus, can be obtained to evaluate narrowing of the acromiohumeral space (Fig 19-1).

Magnetic resonance imaging (MRI) imparts the best image of a torn rotator cuff, showing the subscapularis tendon and status of the deltoid muscle. The size and shape dimensions of supraspinatus and infraspinatus tendon tears are also revealed. Pre-operative evaluation of muscle atrophy is another advantage of MRI. MRI muscle evaluation can show normal muscle, partial fatty infiltration of one muscle, complete atrophy of the supraspinatus, or atrophy of the supraspinatus and infraspinatus (Fig 19-2).

Smaller scanners and newer software afford excellent images in a convenient office setting. The orthopaedic surgeon should personally review the MRI scan.

The office radiographs and MRI complement the patient’s history of symptom onset, discomfort, and loss of function. Discuss the ease or difficulty of repair with the patient as well as the extent of rehabilitation and the expected result. Surgery provides good pain relief. Weakness, however, is slower to recover and will recover incompletely if there is significant muscle atrophy. Patients with significant pain are usually unaware of any accompanying weakness. The patient should have a clear idea of the goals and problems of surgery. Despite these caveats, some patients will have unrealistic expectations for surgical correction of their symptoms. We also point out to the patient that an MRI obtained after surgery may show incomplete healing of the rotator cuff repair (1).

Small to large tears of the supraspinatus and infraspinatus tendons can be repaired by standard arthroscopic repair techniques. Tear size and configuration dictate the specific surgical technique. Repair usually requires a combination of a margin convergence and a tendon-to-bone repair using suture anchors. The goal of margin convergence is to reduce the tension on the tendon to bone repair. Margin convergence involves suturing the anterior and posterior leaves of the tear in a sequential side-to-side manner, starting medially and proceeding laterally until the tear converges toward the bony footprint. The free edge is then attached to the footprint with suture anchors. The value of an arthroscopic rotator cuff repair is that one obtains a secure arthroscopic repair through smaller incisions, without disruption of the deltoid muscle attachment. The final repair is “decompressed” by smoothing the undersurface of the acromion.

Arthroscopic repair of a massive cuff tear is unpredictable. Surgical visualization and mobilization determine whether a massive tear is repairable, partially repairable, or irreparable. A tear is not deemed irreparable until it is evaluated at the time of arthroscopy. Many tears that appear irreparable pre-operatively can be mobilized by capsular techniques and interval slides (2), enabling a partial or complete repair of a once “irreparable” tear. These patients with massive tears usually obtain good pain relief but continue to have weakness due to atrophy of a cuff muscle (3).

If the tear is indeed irreparable, debride the bursal tissue but preserve the coracoacromial arch. Some surgeons prefer to “decompress” the undersurface of the acromion by making the underside of the acromion flat. But the insertion of the coracoacromial ligament onto the undersurface of the acromion must be preserved. If the coracoacromial ligament is removed, the humeral head may “escape” anteriorly, leading to anterosuperior shoulder instability.

Partial repair of a massive rotator cuff tear—namely, the subscapularis or infraspinatus tendons while leaving a defect in the supraspinatus tendon—may be helpful (4), improving pain and function by restoring the rotator cuff cable and force couples necessary for arm elevation (2).

There are many different strategies that have been described regarding the management of rotator cuff tears arthroscopically. The following techniques are the authors’ preferred approach to this problem.

The surgeon must balance skill versus ego in arthroscopic rotator cuff repair. He or she must be in control of the operating theater. Detailed knowledge of the proper tools for passing suture through the cuff, suture management, and knot tying techniques is essential. The skills required for the specific steps can be honed using a shoulder model.

The surgeon must have not only a favorite plan, which we will call Plan A, but also Plan B as well as Plan C. A surgeon who is learning arthroscopic rotator cuff repair can easily bail out of the arthroscopic procedure at any time and proceed to an open repair of the rotator cuff through a mini deltoid-splitting incision.