(a–d) Radiographs of the shoulder including true lateral (i.e., Grashey), axillary lateral, supraspinatus outlet, and acromioclaviclular (i.e., Zanca) views were normal except for moderate AC joint osteoarthritis
The MRI revealed rotator cuff tendonitis and a small partial-thickness anterior supraspinatus tendon tear
The patient’s history, physical, and imaging findings are consistent with the diagnosis of symptomatic partial-thickness rotator cuff tear. Initial treatment was nonoperative including rehabilitation, NSAIDs, and avoidance of overhead activities. The symptoms persisted so a subacromial injection of lidocaine and cortisone that resulted in immediate diminished pain that persisted for several weeks was important in ruling out other causes of shoulder pain such as cervical radiculopathy and malingering. This is important because rotator cuff tears are prevalent, especially in the elderly and even in athletes but are not always the cause of a patient’s shoulder pain . I read the shoulder MRI myself to guide the patient in the expected postoperative treatments. I debride tears of less than 50% of the tendon thickness and allow early range of motion and I repair those involving more than 50% as this much of the tendon has to be torn before there is sufficient tendon tissue to hold a suture. When the intact tendon overlying the articular sided tear appears normal, as with this patient, I perform the repair without completing the tear. Only when the intact tendon is damaged do I complete the tear before doing the repair. When there is AC joint osteoarthritis as with this patient, some physicians prefer to routinely excise the distal clavicle. I have been successful using the absence of tenderness at the AC joint and the absence of pain at the AC joint with cross-body motion in leaving the AC joint alone. However, it has been my experience that these signs are commonly found in worker’s compensation cases.
Partial-thickness rotator cuff tears can be treated with an arthroscopic repair without completing the tear by utilizing the following techniques: (1) making a small longitudinal incision over the tear in the intact portion of the tendon; (2) while viewing the articular side of the tendon, making multiple passes with a small instrument, such as an 18 g spinal needle through the intact margin of the torn tendon; (3) tying the sutures on the bursal side of the tendon; and (4) performing a subacromial decompression if the surgeon thinks it is helpful. Each case must be taken on an individual basis, as the findings at arthroscopy direct the surgeon through the best method of repair. For example, the intact tendon at the location of the partial-thickness tear is often robust and there is little retraction of the torn tendon making it amenable to repair without completing the tear (Fig. 3.3a, b). But if the intact tendon is stretched, such that there is excessive retraction of the tear, then excising the stretched tendon, known as completing the tear, and using techniques detailed in Chap. 4 is the best course.
(a) Arthroscopic picture of the partial-thickness rotator cuff tear with a robust intact portion of the tendon and little retraction that is amenable to repair without completion of the tear. (b) Arthroscopic close-up picture of the partial-thickness rotator cuff tear and little retraction of the tendon that is amenable to repair without completion of the tear
With the patient in a lateral decubitus position and the arm suspended in about 45° of abduction and 15° of forward flexion, a standard posterior portal is made for viewing. The articular surfaces, labrum, biceps tendon, subscapularis tendon, and infraspinatus tendon are normal. A standard anterior portal is also made lateral to the coracoid and entering the joint between the biceps and subscapularis tendons. There is a 15 mm partial-thickness anterior supraspinatus tendon tear of about 60% of the tendon thickness (Fig. 3.4). The determination of the percent of the supraspinatus tendon tear is assessed by looking at the width of exposed tuberosity and knowing the average footprint is about a centimeter and a half in thickness and not by looking at the tendon as fraying and retraction make this difficult. For example for an average-sized person if 9 mm of the greater tuberosity width is exposed, then 60% of the tendon thickness is torn. The surgeon then has the choice of doing the repair or going into the subacromial space and doing a bursectomy to make it easier to find the sutures in the subacromial space after the repair. I usually do the former as doing the bursectomy often makes it difficult to see the tear afterwards.
The intact tendon over the partial-thickness rotator cuff tear is longitudinally incised in line with the collagen fibers with the spine needle in place that was used to localize the tear
I plan to make a portal about 2 cm off the lateral acromion. I start by using an 18 g spinal needle in this location that I then place into the tear as a guide. Adjacent to the needle I make an incision in the skin for a portal with a #11 scalpel and also make a longitudinal incision in line with the fibers of the supraspinatus tendon through the intact portion of tendon over the PASTA lesion (Fig. 3.4). A 6 mm cannula is placed into the joint and I debride the torn tendon with a shaver and greater tuberosity with a burr (Fig. 3.5). This portal is not usually good for placing the anchor as trying to do so would skive the humeral head. A portal about 3 mm in size, just large enough for placing an anchor loaded with two sutures, is made adjacent to the lateral acromion. I once again use an 18 g spinal needle as a guide starting in this location and placing it into the tear. If the anchor is placed without a cannula, as I do, it can be a challenging part of the procedure. More than one anchor can usually be placed without additional incisions in the anterior and posterior greater tuberosity by holding the arm in either external or internal rotation, respectively. The edges of the torn tendon are debrided (Fig. 3.6) with a shaver and the exposed tuberosity is burred (Fig. 3.7). The sutures are then pushed into the joint with a suture passer so that they will be easy to retrieve though the anterior portal (Fig. 3.8). An 18 g spinal needle is placed through the anterolateral shoulder and into the anterior, intact portion of the tendon about 5–7 mm medial to the edge of the tear. A suture relay is passed through the 18 g spinal needle and retrieved out of the anterior portal along with one limb of one of the sutures (Fig. 3.9). The suture is placed into the suture relay and shuttled out the anterolateral shoulder (Fig. 3.10). The 18 g spinal needle is again placed through the anterolateral shoulder about 7 mm anterior to the first suture into the intact portion of the tendon. The suture relay is passed through the 18 g spinal needle and retrieved out of the anterior portal along with the other limb of the suture that is then again shuttled out the anterolateral shoulder that is then tied and will result in a mattress suture. A second mattress suture is placed anterior to the first (Fig. 3.11). The arthroscope is then placed in the subacromial space and if the sutures can be seen they are retrieved and tied. If they cannot be seen then a bursectomy must be done very carefully so as not to cut the sutures! To avoid doing so I start the bursectomy in the subdeltoid space, lateral to the sutures and move posterior first (Fig. 3.12). My assistant pulls on the sutures to make them taut and before starting the bursectomy I use the shaver as a probe, with the blade not moving, to give me an idea of where the sutures are. I can usually find the sutures after clearing the subdeltoid space (Fig. 3.13). On rare occasions I will debride some of the subacromial space around the sutures to better expose them (Figs. 3.14 and 3.15). More commonly if I cannot find them, I use the suture retriever as a probe while my assistant pulls on the sutures to keep them taut and this helps me to find the sutures in the remaining bursa. Once I find one and determine which one it is, it helps me to find the rest. I then tie the sutures to complete the repair (Fig. 3.16), and then complete the bursectomy of the subacromial space and then do a subacromial decompression. The necessity of subacromial decompression with rotator cuff repair is controversial. Lastly, the arthroscope is placed into the joint to assess the repair (Fig. 3.17).