Abstract
It is not clear that there is a specific definition for a massive rotator cuff tear, but it can be loosely defined as one that involves two complete tendon tears or one that is as greater than 5 cm in length from anterior to posterior. It is difficult for surgeons to determine whether a massive, retracted rotator cuff tear is reparable. These tears take more time to assess and to repair. Meticulous attention must be paid to tear pattern, size, tissue quality, and technique. Techniques of mobilization involving soft tissue releases and recognition of tear pattern can simplify the procedure. Even with the most advanced technical skill, these tears still have a higher failure rate and often are only partially reparable.
Keywords
massive tear, margin convergence, tear pattern, tissue quality, retraction, mobilization
It is not clear that there is a specific definition for a massive rotator cuff tear, but it can be loosely defined as one that involves two complete tendon tears or one that is as greater than 5 cm in length from anterior to posterior. It is difficult for surgeons to determine whether a massive, retracted rotator cuff tear is reparable. This is true for both arthroscopic and conventional open techniques. If the tendon is mobile and can be advanced to its anatomic location or medialized within 10 mm of its anatomic location without shoulder abduction, the tear is reparable. If, on initial inspection, the tendon does not meet these criteria, it is not necessarily irreparable. Subacromial, subdeltoid, and intra-articular adhesions may limit cuff excursion. With an arthroscopic technique, the surgeon can release these adhesions and determine definitively whether the tear is reparable. Sometimes, large tears are only partially reparable, but that may yield a better outcome than no repair at all.
In order to repair massive tears, débridement and soft tissue releases must be done to determine reparability. The arthroscope may need to be moved to different cannulas to get a perspective of the tear geometry. Large or massive retracted rotator cuff tears differ from smaller tears in six aspects:
- 1.
Quantity of sutures and anchors
- 2.
Tear geometry
- 3.
Variability of repair sequence
- 4.
Suture management
- 5.
Tendon-to-tendon repair
- 6.
Muscle quality
The most straightforward aspect is quantity of sutures and anchors. Larger tears require more anchors, more sutures, and more time to complete.
Tear geometry is difficult to identify. Larger tears often assume distorted shapes because the tendons have detached, rotated, and come to rest far from their insertion sites. The tendon has deformed plastically. It is often difficult to understand how points on the retracted tendon attach to corresponding points on the humeral head. Identifying this relationship requires an understanding of the geometry of the tear and thus the geometry of the repair ( Fig. 13.1 ). This is difficult enough when then tendon is mobile, but it becomes increasingly complex when the tear is retracted and fixed. Only with thorough soft tissue releases can the surgeon maneuver the tendon and determine the precise repair site.
The surgeon must often alter the normal repair technique of placing anchors from anterior to posterior and tying knots from posterior to anterior. The repair may require knot tying from anterior to posterior, or the surgeon may have to repair the most anterior and posterior margins first and repair the central portion last.
In addition, suture management is complex. As the number of anchors and sutures increases, the technical difficulty seems to increase geometrically. Strict adherence to two principles is vital: keep the working cannula free of sutures, and transfer suture strands so they do not cross the area of tendon repair.
It is often necessary to combine a longitudinal tendon-to-tendon repair with a transverse tendon-to-bone repair. This may require the use of different suturing techniques, sutures, instruments, viewing portals, and knot-tying methods ( Fig. 13.2 ).
Finally, massive rotator cuff tears are diseases of tendon and muscle. These large tendon tears are usually chronic and are accompanied by significant muscle atrophy. The surgeon must be aware that heroic efforts to repair tendons will not produce a successful result if the corresponding muscles are not functional.
Literature Review
Cordasco and Bigliani reported on the open repair of massive rotator cuff tears. In their series, 85% of patients (52 of 61) had satisfactory results, and 92% (56 of 61) had satisfactory pain relief; they experienced mean gains of 76 degrees in forward elevation and 30 degrees in external rotation. Burkhart reported similar results with the arthroscopic treatment of massive tears. Burkhart has also contributed greatly to our understanding of the biomechanics of massive rotator cuff tears and their repair. The concept of margin convergence is particularly useful. The first principle of margin convergence is that partial repair of a massive tear can reduce the patient’s pain and improve function. Complete anatomic repair, though desirable, may not be possible in patients with massive rotator cuff tears; however, a good outcome can be achieved with a partial repair. The second principle is that if the surgeon can establish anterior and posterior force couple of the shoulder, good function is possible even if the supraspinatus is not reparable. The anterior force couple component may be established with subscapularis repair, and the posterior force couple component may be established with infraspinatus repair.
The healing rate of large and massive tears has been reported by a number of authors, with healing rates ranging from 0% to 80%. There appears to be a higher healing rate with modern double-row fixation techniques. Warner (see Costouros et al.) discussed the possibility that abnormalities of the suprascapular nerve may be partially responsible for pain in patients with retracted tears. It is not unreasonable to assume that tendon retraction and the resulting distortion of the suprascapular nerve could be a source of pain.
Operative Technique ( – )
Visualization
Visualization of a massive rotator cuff tear can often be easier than for a smaller tear since a large volume of tissue, the rotator cuff, is displaced medially. However, some acute massive tears can be difficult to visualize if the torn margins of the rotator cuff are thickened or shredded. The camera is initially placed in the posterior portal, as usual, in the glenohumeral joint. The size of the tear may or may not be appreciated from this view. The arthroscope is then removed and the trocar is inserted in the arthroscopic cannula to allow placement into the subacromial space. This is done as described in Chapter 12 where the cannula is placed to the level of the anterior acromial corner and then swept medially and laterally. This is done to ensure that any torn rotator cuff tissue that is adherent to the acromial undersurface is stripped and placed below the camera. A lateral portal is established and used to remove any obstructive bursa and to allow the camera to be transferred to the lateral portal ( Figs. 13.3–13.10 ).
Cuff Mobilization and Tear Classification
Several steps are done simultaneously at this point. The tear pattern is identified while mobilizing the rotator cuff tissue. With small to medium tears, the size and tear geometry are easily appreciated, but this is often not the case with massive tears. Fundamentally, rotator cuff repair is a question of what goes where and how to get it there. The size and retraction of massive tears often make implementing the appropriate repair steps difficult. Even when the surgeon understands the tear geometry, mobilizing the tendon is difficult. Retraction from muscle contracture limits the excursion of the tendon edge even when the surgeon has performed the appropriate releases. This is certainly less of a problem for acute massive tears, but can be a problem for acute massive tears as early as 4 weeks post injury.
With the arthroscope in the lateral portal, a shaver and cautery are used alternately through the posterior and anterolateral portals to clear the undersurface of the acromion laterally, and to ensure that all adhesions between the acromion and the rotator cuff are disrupted. Adhesions between the rotator cuff and the deltoid are then released in the anterior, lateral, and posterior gutters ( Figs. 13.11 and 13.12 ).
Once the lateral aspect of the subacromial space, including structures (e.g., the rotator footprint), is well visualized, progress can be made medially to release adhesions to the scapular spine posteriorly and to the acromioclavicular joint anteriorly. An electrocautery should be used here as this area is quite vascular and will likely result in bleeding and loss of visualization ( Figs. 13.13–13.16 ). Adhesions to the coracoid or a coracohumeral ligament contracture may give a false impression of irreparability. Adhesions in this area are usually very thick and require resection with electrocautery. This is particularly true in the area of the coracohumeral ligament. This ligament is often not clearly visualized and is best appreciated by applying lateral traction to the tendon edge, and observing a ridge of tissue that prevents mobilization. The tendon edge is grasped with a soft tissue grasper inserted through the posterior or lateral portal, while an electrocautery is inserted through the anterior or anterolateral portal to divide the ligament ( Figs. 13.17–13.22 )