**2.2 Surgical technique**

For developing a posterior arthroscopy portal, a stab incision of the skin is made 2 cm caudal and 2 cm medial of the posterolateral corner of the acromion. After entering the glenohumeral joint with a switching stick, the arthroscopy sheath is introduced, the joint is filled up with water, and the arthroscope is inserted. At first, a diagnostic arthroscopic evaluation and incision for the anterior inferior working portal in outside-in technique just above the subscapular tendon is performed. In this antero-inferior working portal, a working cannula (8.25 mm) is inserted. Alternatively, a 5:30 o'clock portal can be used about 8 cm distal to the coracoid through the inferior (muscular) part of the subscapularis tendon. This facilitates placement of the first suture anchor as low as recommended.

An additional antero-superior portal is developed directly anterior to the acromio-clavicular joint (ACJ) in outside-in technique and a working cannula (5.5 mm) is introduced here. The **Figures 2**–**4** illustrate the surgical technique:

#### **Figure 2.**

*The lasso-loop stitch (a-d). A Birdpeak is pushed through the capsulolabral complex from anterior (a). Then, one suture end of the anchor is grasped (b), pulled through the capsulolabral complex anteriorly, and formed into an intraarticular loop (c). The Birdpeak is pushed through the loop and the same suture end is grasped again (d). Now, the Birdpeak is kept closed and the suture end is pulled out of the shoulder joint through the working cannula. During this procedure, the other suture end outside of the shoulder joint is secured by a clamp.*

#### **Figure 4.**

*Right shoulder after arthroscopic anterior stabilization.*

Examination with a hook probe, mobilization of the labrum with the Bankart raspatory and debridement of the glenoid neck with the Bankart rasp.

Trial cranialisation of the capsulo-labral complex is performed via a grasper through the anterior superior portal followed by insertion of a hold-suture (PDS no. 0).

The first single-armed resorbable suture anchor is positioned through the anterior inferior portal onto the anterior glenoid rim as caudal as possible at the anterior cartilage border. The anchor is inserted ca. 135° to the glenoid plane. Not too steep and not too flat. The anchor should not be inserted too deep either; under no circumstances should the end of the anchor stick out. Because this could lead to cartilage damage and it could potentially cause anchor dislocation.

Cranialisation of the labrum is accomplished using the hold-suture. Then, refixation of the capsulo-labral complex in lasso-loop technique is performed. Also the second suture end is stitched through and behind the labrum, so the knot comes to lie away from the joint. This suture end represents the drawstring. Seven singular knots are made.

Then, the clamp is switched and with the birdpeak (or a suture lasso) the second suture end is pulled anteriorly through the labrum and outside of the joint through the antero-inferior working cannula.

Now, the hold-suture can be removed as it is no longer needed after tying of the first antero-inferior suture anchor.

Slightly further cranial, labral refixation is undertaken in the same way with the second anchor. A further hold-suture is not needed after the first anchor is sutured.

In most cases, an additional third anchor is necessary further cranial for secure labral refixation using the same technique. Enough distance has to be kept from the long head biceps tendon origin not to compromise this tendon mobility.

Final examination of labrum stability with a hook probe and careful clinical verification of joint stability.

Removal of instruments, skin disinfection, closure of the arthroscopic portals via interrupted single Donati backstitches, and sterile wound dressing as well as immobilization with a sling.

#### *2.2.1 Tips and tricks*

For improved arthroscopic evaluation of potential glenoid bone loss and subluxation of the humeral head, we recommend arthroscopic view via the anterior superior portal.

Only if the second suture end is also positioned behind the labrum, the knot will come to lie away from the joint surface.

Pulling on the one suture end without the loop reattaches the capsulo-labral ligament complex to the glenoid. Strain to the other suture end – the one creating the loop – would pull the tissue away from the glenoid. Therefore, the singular stitched suture end has to be the drawstring while tying the knot.

When using the lasso-loop technique, only one of the anchor dependent suture ends can slide through the tissue. Therefore, no arthroscopic slip knots can be made. Seven half hitches come into use. Alternating half hitches lead to a secure blocking of the knot.

#### **2.3 Postoperative treatment**

Postoperatively, physical therapy out of a sling or Gilchrist bandage for four to six weeks with external rotation limited to 20° is applicated. Clinical follow up with the surgeon at six weeks postoperatively is recommended for clinical control. Then, careful unlimited motion is allowed. No forced external rotation should be performed for further six weeks. Training of the active and dynamic stabilizers of the shoulder girdle is important. Throwing and contact sports can be taken up again at the earliest six months postoperatively, if power and coordination are fully restored [18–22].

#### **3. Results**

For one year, we followed up our operatively treated patients using the described technique after antero-inferior shoulder dislocation with damage to the glenoid labrum. We identified all 30 consecutive patients (3 females, 27 males), who had been treated for shoulder dislocation with anterior-inferior damage to the glenoid labrum by arthroscopic refixation of the anterior capsulolabral complex with suture anchors in lasso-loop technique. Patients with relevant anterior-inferior bone loss or Bankart fracture >15% of the glenoid joint surface received either bony augmentation or osteosynthesis and were not part of the patient cohort used for this analysis.

Five patients were either not available or not prepared to take part in the followup examination. 25 of 30 patients could be followed up. One patient had to be excluded for a recent ipsilateral elbow fracture dislocation. In this case, no shoulder re-dislocation occurred. In total, we followed up three female and 21 male patients completely. The mean age was 27.8 years (17–49 years). The average follow-up took place 30.4 months (25–36 months) postoperatively.

In 96% of all cases, there was an excellent subjective and objective outcome. The average Rowe Score was 96.3 points (80–100 points; SD = 3.9). The mean QuickDash was 2.8 points (0–14 points, SD = 3.9). The Constant Score had an average of 93.7 points (65–100 points, SD = 8.8). The average pain level on the numeric analogue pain scale (NAS 0–10) was very low with reported 0.4 points (0-3 points, SD = 1.0). The average passive and active range of motion of the operated glenohumeral joint was Ext/Flex 30/0/170°, Abd/Add 70/0/20°, and Ero/Iro 60/0/95°. There was no restriction of movement greater than 10° compared to the other side. No significant difference in passive or active range of motion in comparison to the healthy side could be seen. The rotator cuff tests were negative. The anterior

apprehension sign was negative in all cases; in one case accompanied by slight pain. Apart from one traumatic re-dislocation during handball there were no further complications.
