Figure 10.1
(a) Coronal T2-weighted MRI image revealing large rotator cuff tear. (b) Sagittal oblique image showing AP extent of tear. (c) TI-weighted image documenting moderate fatty infiltration of the supraspinatus
Management
The surgery can be done under general anesthesia with or without an associated interscalene block or under an interscalene block with sedation. The patient is positioned in a sitting position with the head secured on a headrest and the entire shoulder and right side of the chest—anterior and posterior—exposed. An arthroscope is introduced into the glenohumeral joint through a posterior portal, and an anterior portal established from inside-out. A shaver is passed though the anterior portal, and the joint debrided as needed. The long head of the biceps and the joint side of the cuff tear are inspected. The scope is redirected to the subacromial space and a lateral portal is made through which the shaver is reintroduced to debride enough of the bursa to allow clear visualization of the cuff tear, the coracoacromial ligament, and the anterior inferior acromion. This step can be facilitated by using an electrocautery wand.
Before doing an acromioplasty, a grasper is placed through the lateral portal as well as a small elevator to free the tendons up. Traction via the grasper allows us assessment of the mobility of the tendons, which determines if they can be repaired. If the tendons are not mobile and we do think a repair can be done, a subacromial decompression is not done so as to minimize the complication of anterior-superior escape. Using the electrocautery wand, the coracoacromial ligament is released. If we think a repair is possible we further tailor the amount of release by how confident we are about the strength and security of the repair. If a good repair can be achieved, then a complete ligament release is done; but if there is any concern about the security of a repair, then the lateral one-third only is released in order to avoid the complication of anterior-superior escape. The periosteum of the undersurface of the acromion is removed with the wand and a burr is used to perform an acromioplasty to give the repaired cuff room to glide under the acromion. One can also place nonabsorbable traction sutures through the torn cuff with a suture punch to provide traction to the tendons throughout the mobilization process but only after any decompression is performed; otherwise these sutures may be cut during the decompression.
An incision is made slightly medial to the anterolateral corner of the acromion and extended through and in line with the fibers of the deltoid. An elevator is used to free the subdeltoid space around the entire glenohumeral joint. If traction sutures have not already been placed, serial traction sutures are placed in the cuff. After placing each, further mobilization is done with an elevator, bringing the torn edges farther and farther toward the anatomic neck and tuberosity. Using these steps, eventually the apex of the tear is reached, which completes the control of the cuff. If additional mobility is needed, the intervals between the supraspinatus and subscapularis as well as those between the infraspinatus and teres minor can be split longitudinally to allow the supraspinatus and infraspinatus additional mobility. The subscapularis and most of the teres minor are often intact. Release of the coracohumeral ligament from the coracoid base is also helpful. If necessary, a small elevator can be placed between the undersurface of the cuff and the superior labrum to free the tendons even more. A biceps tenodesis is done by suturing the tendon of the long head to the transverse humeral ligament with three, figure-of-eight, nonabsorbable sutures, and the intra-articular portion is excised and saved for possible use later.
If mobilization has allowed the cuff edges to be brought to the anatomic neck at the greater tuberosity, this area is then lightly roughened with a curette; a deep trough is not necessary. The torn edges of the tendons are minimally trimmed, and suture anchors, loaded with #1 nonabsorbable sutures, are placed into the anatomic neck (Fig. 10.2). The sutures are passed through the cuff tendons from inside-out spaced approximately 8–10 mm apart (Fig. 10.3). The number of anchors is determined by how many are needed to bring the cuff to its desired insertion. The suture limbs are then arranged in twos or threes to cross and be secured in a transosseous pattern and secured below the greater tuberosity with pushlock anchors (Fig. 10.4).
Figure 10.2
Suture anchors placed in a roughened area at the anatomic neck
Figure 10.3
Sutures passed from the deep surface of the cuff tendons to exit on the bursal side
Figure 10.4
Cuff reduced to tuberosity and secured with a transosseous equivalent configuration secured below the tuberosity using pushlocks
Because this patient had a history of shoulder pain before the current injury, this tear may represent an acute on chronic, preexisting tear. In some instances, direct repair may not be possible. There are alternative techniques available which can be used. Fortunately, they are rarely needed. These include partial repair, interpositional grafts, and local or distant tendon transfers. Partial repair involves inserting the tendon edges into a site on the humeral head that is medial to the greater tuberosity. This can be successful if the insertion site itself is lateral to the apex of curvature, or very top, of the humeral head.
Interpositional Grafts
The absolute requirement for grafting is that the residual, intact portion of the rotator cuff tendons is mobile and that the muscles do not have extensive fatty infiltration. A graft is only a means of extending the length of the functioning muscle unit so that it can perform its natural function. If the native muscle does not work, the graft itself cannot replace the muscle’s function. Thus, the residual cuff should exhibit a springy feel when traction is applied to it. These interpositional graft techniques are not the same as and do not serve the same purpose as the so-called patch graft.
For smaller residual defects, the previously excised intra-articular tendinous portion of the long head of the biceps is filleted (Fig. 10.5) and placed into the defect [3]. It is contoured to accommodate the configuration of the defect and sutured to the residual cuff tendons. Its lateral edge is then sutured to the roughened area of the anatomic neck at the greater tuberosity as described above for a direct repair.