The portals commonly used are the posterior (located approximately 2–3 cm inferior and 1 cm medial to the posterolateral corner of the acromion at the “soft” spots), the lateral (located approximately 1.5–3 cm lateral to the acromion in line with the posterior aspect of the clavicle), superolateral (percutaneous portal is located just lateral to the edge of the acromion), and anterolateral (utility portal located midway along the anterolateral acromial corner and the tip of the coracoid). The mid-glenoid portal is required only if there is an intra-articular operative time (tenotomy/tenodesis of the long head of biceps; synovectomy, debridement of the labrum or insertion of the biceps tendon).

The anterior, anterolateral, and lateral portals are established after introduction, in the alleged right spot, of an 18-gauge spinal needle (pink needle) with out-in technique. For the lateral portal, the needle should be centered on the apex of the medial tendon injury in order to have easy access to both posterior and anterior edges of the tear. This access will be the one through which we will carry out the repair (for surgeons using only the posterior portal); that will be used alone or, alternatively, with the posterior portal, for the direct view of the lesion; for the introduction of the anchors (metallic or plastic resorbable material and nonresorbable one); for tear margins preparation and for the execution of the acromioplasty, if this surgical procedure is necessary. In the lateral portal, an 8-mm cannula is usually inserted. Instead, in the anterior one, a 5.5-mm cannula is inserted. It is used for suture threads recovery or for anchors positioning [7–9] (Fig. 3).

The instrumentation required for cuff repair with single-row technique is represented by a grasper used to test the mobility of the tissue and to retrieve the suture thread once passed in the tendon, a passing suture (as Scorpion, Elite, TruePass, suture hooks, etc), a crochet hook, (alternatively a clamp ring), and one knot pusher to carry out the sutures (Fig. 4).

Since my job is also to teach, I perform the operation with two young colleagues. The entire operation is registered in order to have a useful documentation for teaching.

Obviously, the first operation time is the intra-articular view with the arthroscope inserted through the posterior and anterior portals. I run the 15 common steps (changing the portals), as suggested by Snyder (Table 1) [10].

The observation of these structures is firstly performed keeping the arm along the side and then performing abduction, flexion, internal, and external rotation movements in order to obtain a dynamic view of the same.

Subsequently, the arthroscope is inserted into the subacromial space. It is recommended that the optic is kept parallel to the inferior surface of the acromion to prevent that the liquid that flows from the portal impairs the vision. I run the bursectomy if necessary, with a radiofrequency ablator (Fig. 6) and a shaver.

Usually, I remove only the bursa that obstructs the view of the tear edges, exposing the same for at least 1.5 cm. The use of radiofrequencies reduces the risk of bleeding; therefore, they are preferred to the shaver; however, in case of subacromial bursa hypertrophy, radiofrequencies are not able to remove the exuberant tissue. The arthroscope is then moved to the lateral portal; it gives you a clearer idea of tear shape and extension. It is important to verify also the presence of a delamination of tendon edges.

I perform the single-row technique only in cases of type crescent tears.

The frayed edges of the rotator cuff tendon are debrided using a 4.2-mm shaver or a basket (Fig. 7). Successively I assess the pattern of the tear using a soft tissue grasper through the anterior and posterior portal and experiment with various options to reposition the tendon back to the footprint and for possible side-to-side sutures. To check the tightness of the suture, Gartsman [7] has recommended to pass a high-resistance No. 2 wire with a suture passer and then trying to mobilize the margin of tear; obviously a not repairable tissue is the one cut by the thread with no mobilization of the same.

I use a bur in order to prepare a suitable bleeding footprint having care not to remove an excessive quantity of bone since the holding of the anchors could then be compromised (Fig. 8). The length of the footprint will be equal to the length of the lesion from anterior to posterior.

Take care to avoid cutting out and damaging the articular cartilage. Single-row suture anchor techniques typically use a linear row anchors inserted approximately 5 mm lateral to the articular surface (Fig. 9a–d). I usually use titanium 5 mm anchor. In some young patients (<45 years), I used absorbable anchors of the same size.

The angle of incidence to the bone is crucial. Anchors are ideally placed with a deadman angle, as described by Burkhart [4, 11], of less than 45°. If the insertion angle is too vertical, it will enter the softer bone of the greater tuberosity rather than the dense subchondral bone of the humeral head, increasing the risk of anchor pullout. The metallic anchor should simply be screwed and not beaten. The absorbable anchors and those in peek may require the execution of a hole on the greater tuberosity (using a bone punch), within the anchor that is introduced. Once inserted, regardless of the material, it is right to verify its resistance to pullout and that the stitches slide freely in its hole.

Using double-loaded and/or triple-loaded suture anchor reduces the load at the suture-tendon interface and provides more secure fixation [11–13].

The anterior anchor is the first to be inserted; then, the arm is placed in external rotation to allow a better view of the anterior portion of the greater tuberosity. The sutures are retrieved by the assistant through the anterolateral portal (Fig. 10a, b). If more than an anchor is needed, the stitches of the first anchor are retained together with a Klemmer through the anterolateral portal, but outside the cannula (Fig. 11), so that in the latter only the sutures with which you are working are always present. In this way, the sutures from different anchors do not intertwine.

The sutures are passed through the tendon tissue through the use of suture passers (Fig. 12a–c) or suture hooks. The latter allows the pass in the tendon of a shuttle relay that is used as an entrainment wire for the suture.

Surgeon has to choose the appropriate suture hook that affords the best angle for passing the needle through the cuff. Shuttle has to be clamped near the tip of the needle, and while feeding it by turning the rubber wheel, located on the handle of the hook, carried it out the anterior or lateral portal. Successively, shuttle is loaded with the suture outside the cannula and carried back through the cuff from bottom to top and out the back. The partner limb of the sutures is retrieved out the lateral or anterior cannula with a crochet hook for knotting.

At the beginning of my arthroscopic career, I used a modified Caspari suture punch.

Usually I use an SMC knot (Fig. 13a–g). An important technical consideration when performing single-row repairs is to use mattress, Mason Allen, massive cuff stitch, or comparable suture configurations to improve the biomechanical strength of the repair [14–18].

Obviously, knotless anchors or like-chain, like-tape sutures, and other devices can be used.

When necessary, acromioplasty is performed using a bur (Fig. 14a–e).