Arthroscopic Repair of the PASTA Lesion
Partial rotator cuff tears can involve the articular surface, the bursal surface, or both. The extent of the partial tear can be further classified based on the severity of the lesion (Table 14–1). When these tears are of the AIII or AIV variant they may be considered a PASTA lesion (PASTA from the first letters of “Partial Articular Supraspinatus Tendon Avulsion”). These tears have significant tendon fragmentation or a flap component that is very amenable to arthroscopic repair.
A large partial articular surface rotator cuff tear, AIII or AIV type, with at least 25% good quality bursal tendon remaining.
1. Complete rotator cuff tears
2. Partial articular surface tears with significant bursal involvement (BII, BIII, BIV types)
1. These lesions are common in patients less than 45 years old, especially those who participate in repetitive overhead sports (tennis, baseball, volleyball, swimming).
2. Pain often continues for several hours after cessation of the activity.
1. Pain or weakness on resisted isometric contraction of the involved muscle.
a. Supraspinatus: resisted elevation with the arm held in 90 degrees of abduction with slight internal rotation
b. Infraspinatus: resisted external rotation with the arm at side in neutral rotation with the elbow flexed 90 degrees
2. Associated posterior capsular tightness.
3. Perform an instability examination in the throwing athlete.
1. Standard radiographs of the shoulder. The supraspinatus outlet view is the most important view to delineate coracoacromial arch morphology.
2. Gadolinium-enhanced magnetic resonance imaging arthrogram to detect articular surface lesions.
1. 18-gauge spinal needle and #1 absorbable monofilament suture
2. 4-mm full-radius shaver blade
3. 5/64 smooth K-wire
4. Power drill
5. Shuttle Relay (Linvatec, Largo, FL)
6. 4-mm Revo titanium suture anchor screws with large eyelet, double loaded with #2 Ethibond suture (two colors) (Linvatec, Largo, FL)
7. Arthroscopic loop-handled knot pusher
General anesthesia is used.
Patient and Equipment Position
1. Lateral decubitus position on a beanbag.
2. The arm is prepped and placed in a STaR sleeve traction device (Arthrex, Naples, FL).
3. The arm is supported in 70 degrees of abduction, 20 degrees of forward flexion, and 10 Ib of traction.
4. Prior to bursoscopy, the arm is placed in 15 degrees of abduction and 15 Ib of traction.
1. A video-recorded 15-point glenohumeral diagnostic arthroscopic evaluation is performed.
2. A suture marker is placed through the articular side of the lesion for identifying the corresponding area on the bursal surface. Viewing from the posterior portal, an 18-gauge spinal needle is passed through the lesion and a #1 absorbable monofilament suture is inserted through the needle (Fig. 14–1).
3. An eight-point diagnostic bursoscopy is performed and the suture marker is visualized on the bursal side of the cuff.
4. A limited bursectomy is performed to aid in the location and manipulation of sutures during knot tying later in the procedure.
5. A subacromial smoothing is performed only if a significant spur exists.
6. The arm is placed back into 70 degrees of abduction and the arthroscope is reinserted intraarticularly.
7. The humeral insertion of the rotator cuff (“the footprint”) is cleaned with a shaver to provide a surface for tendon healing (Fig. 14–2).
8. A spinal needle is percutaneously inserted near the lateral acromial border and visualized intraarticularly to determine the correct angle and position for insertion of the Revo suture anchor.
9. Through a small incision chosen by the spinal needle, a 5/64 smooth K-wire is drilled to create a pilot hole for screw insertion (Fig. 14–3).
10. The 4-mm Revo screw is loaded with two sutures, one green and one white. One half of each suture is colored with a purple skin marker. Both purple-colored sutures exit the same side of the eyelet. The white suture exits closest to the threads (Fig. 14–4).
11. A Revo screw is inserted with the eyelet and the purple-colored sutures facing toward the medial edge of the tear.
12. The purple-green suture is removed out the anterior portal (Fig. 14–5).
13. The spinal needle is passed through good-quality tendon at the medial edge of the tear (Fig. 14–6).
14. A Shuttle Relay® is placed through the spinal needle and retrieved with a grasper out the anterior portal (Fig. 14–7).
15. The tip of the purple-green suture is loaded onto the Shuttle Relay® and pulled through the tendon (Fig. 14–8).
16. The same step is performed for the purple-white suture (Fig. 14–9).
17. Additional suture anchors are inserted depending on the size of the tear, and the above steps are repeated (Fig. 14–10).
18. Once completed, the arm is placed in the bursoscopy position and the arthroscope is inserted into the subacromial space.
19. A lateral portal is created to facilitate knot tying (Fig. 14–11).
20. The green and purple-green sutures are retrieved out the lateral portal and tied first. The same step is performed for the white and purple-white sutures (Fig. 14–12).
21. The arm is returned to the abducted position and the repair is assessed intraarticularly (Fig. 14–13).