Arthroscopic Dynamic Anterior Stabilization Using Either Long Head of the Biceps or Conjoined Tendon Transfer for Anterior Shoulder Instability Results in a Similarly Low Recurrence Rate

Editorial Commentary: For Patients With Shoulder Instability, On-Track Hill-Sachs Lesion Plus Subcritical Glenoid Bone Loss May Be the Best Indication for Dynamic Anterior Stabilization Using the Long Head of the Biceps Tendon

As the definition of shoulder glenoid critical bone loss has evolved and decreased from 25% to 17% to 13.5%, indications for bone block procedures for shoulder instability with glenoid bone loss have expanded. While the bone block procedure is an effective treatment for almost all cases of anterior shoulder instability, regardless of the amount of bone loss, many surgeons prefer to perform a bone block procedure only in cases of critical bone loss due to risk of complications. Thus, for cases of minimal (subcritical) bone loss, Remplissage has been recommended to enhance Bankart repair. As an alternative, dynamic anterior stabilization (DAS) using the long head of the biceps tendon has been recommended as a surgical option in patients with shoulder instability and subcritical bone loss. How do we decide? A biomechanical study shows DAS is an effective method for on-track Hill-Sachs lesions with subcritical bone loss, and Remplissage is more effective for off-track Hill-Sachs lesions. Clinical studies are required to complement biomechanical findings.

Biomechanical Analysis Reveals Shoulder Instability With Bipolar Bone Loss Is Best Treated With Dynamic Anterior Stabilization for On-Track Lesions and With Remplissage for Off-Track Lesions

PURPOSE

To compare the biomechanical effects of augmenting Bankart repair (BR) with either remplissage or dynamic anterior stabilization (DAS) in the treatment of anterior shoulder instability with on-track or off-track bipolar bone loss.

METHODS

Eight fresh-frozen cadaveric shoulders were tested at 60° of glenohumeral abduction in the intact, injury, and repair conditions. Injury conditions included 15% glenoid bone loss with an on-track or off-track Hill-Sachs lesion as previously recommended. Repair conditions included isolated BR, BR with remplissage, and BR with DAS (long head of biceps transfer). The glenohumeral stability was assessed by measuring the anterior translation under 0, 10, 20, 30, 40, 50 N load and maximum load without causing instability at mid-range (60°) and end-range (90°) external rotation (ER). Maximum range of motion (ROM) was measured by applying a 2.2-N·m torque in passive ER and internal rotation.

RESULTS

Isolated BR failed to restore native glenohumeral stability in both on-track and off-track bipolar bone loss models. Both remplissage and DAS significantly decreased the anterior instability in the bipolar bone loss models, showing better restoration than the isolated BR. In the on-track lesions, DAS successfully restored native glenohumeral stability and mobility, whereas remplissage significantly decreased anterior translation without load (-2.12 ± 1.07 mm at 90° ER, P = .003; -1.98 ± 1.23 mm at 60° ER, P = .015). In the off-track lesions, remplissage restored native glenohumeral stability but led to significant ROM limitation (-8.6° ± 2.3° for internal rotation, P < .001; -13.9° ± 6.2° for ER, P = .003), whereas DAS failed to restore native stability at 90° ER regarding the increased anterior translation under 50 N (4.10 ± 1.53 mm, P < .001) and decreased maximum load (-13.8 ± 9.2 N, P = .021).

CONCLUSIONS

At time-zero, both remplissage and DAS significantly reduced residual anterior instability compared with isolated BR in the bipolar bone loss models and restored the native glenohumeral stability under most translational loads. However, remplissage could decrease the anterior translation without load for on-track lesions and may restrict ROM for off-track lesions, whereas DAS failed to restore native stability under high translational loads for off-track lesions.

CLINICAL RELEVANCE

DAS could be recommended to treat on-track bipolar bone loss with less biomechanical adverse effects, whereas remplissage might be the preferred procedure to address off-track bipolar bone loss for better stability.

Editorial Commentary: Arthroscopic Subscapular Sling Procedure for Anterior Glenohumeral Instability Has Limitations: Dynamic Anterior Stabilization Using Long Head of the Biceps Tendon May Represent a More Favorable Alternative

Anterior shoulder instability is common. Cases of mild glenoid bone loss are typically addressed with conventional arthroscopic Bankart repair procedures, whereas more critical glenoid bone loss often necessitates more invasive, bone-blocking procedures. Recently, for cases that fall between the need for arthroscopic repair and open procedures, surgeons have developed methods for using soft tissue grafts to create a "sling" effect and augment glenoid labral repair. The subscapular sling procedure aims to restore stability by introducing a semitendinosus autograft into the glenohumeral joint to reconstruct the torn labrum; the graft is wrapped around the subscapularis to create a suspensory sling. Limitations include harvest site morbidity; increased surgical time; subscapularis split, which can compromise the tendon integrity, resulting in loss of internal rotation; and a persistently positive apprehension test. Finally, the technique is complex, and similar alternatives with fewer limitations may include a dynamic anterior stabilization technique using the long head of the biceps tendon, which creates a stabilizing sling effect without graft harvest from the leg and has positive reported outcomes.

Long head of the biceps tendon versatility in reconstructive shoulder surgery: a narrative review of arthroscopic techniques and their biomechanical principles with video presentation

The management of the long head of the biceps tendon (LHBT) during shoulder arthroscopy has been a subject of controversy for many years, with evolving discussions and trends. Despite long-standing debate, the nature of the surgical indication regarding how to treat concomitent LHBT injuries has undergone changes in recent years. It now extends beyond the timing of tenotomy to encompass considerations of alternative methods for preserving the LHBT, along with an ongoing exploration of how it can be effectively utilized in reconstructive shoulder surgery. Recent techniques describe approaches to using LHBT in a wide range of procedures, from shoulder instability to rotator cuff tears. Additionally, LHBT-based reconstructive techniques have surfaced for addressing what were formerly denoted as irreparable rotator cuff tears. While current literature provides detailed anatomical descriptions of the LHBT and many reports of novel, advanced techniques, there is still much debate regarding the decision-making process in each case. Because of the growing number of emerging techniques and the escalating debate in the subsequent paper, a decision has been made to present the current literature review concerning the potential utilization of LHBT in shoulder arthroscopy. In a dedicated video, we demonstrate the main arthroscopic techniques employed by the authors in their daily practice.

The Arthroscopic Subscapular Sling Procedure Results in Low Recurrent Anterior Shoulder Instability at 24 Months of Follow-Up

PURPOSE

To analyze the results of the subscapular sling procedure developed for anterior shoulder instability in patients with less than 10% anterior glenoid bone loss.

METHODS

Patients were treated surgically with the arthroscopic subscapular sling procedure. A semitendinosus graft was used to reconstruct the anterior labrum and to establish a sling suspension around the upper part of the subscapularis tendon. The patients were followed up with radiographs (at 12 and 24 months). Magnetic resonance imaging (MRI) of the shoulder region and clinical examinations were performed at 3, 12, and 24 months. Recurrent dislocation was the primary endpoint. The Western Ontario Shoulder Instability Index (WOSI) and MRI results were secondary outcome measures. An independent physiotherapist assessed residual instability and range of motion.

RESULTS

Fifteen patients were included with a dislocation rate of 0% after 24 months follow-up. There was a significant clinical improvement of the WOSI score from 57% (904) at baseline to 88% (241) at 24 months (P < .001). The proportion of patients with an improvement in the WOSI Total score larger than the estimated minimal clinically important difference was 100% both at 12 and 24 months. MRI showed an intact sling in all patients. External rotation was not significantly reduced (52° at baseline vs 47° at 24 months, P = .211). Flexion and abduction were significantly improved from 152° to 174° (P = .001) and 141° to 170° (P < .001) after 24 months. The surgical procedures were completed without any intraoperative complications.

CONCLUSIONS

The subscapular sling procedure resulted in low recurrent shoulder instability and improved patient-reported outcome measures at 24 months of follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Editorial Commentary: Shoulder Arthroscopic Dynamic Anterior Stabilization Is Effective for Anteroinferior Shoulder Instability With Limited Anterior Bone Loss

Shoulder dynamic anterior stabilization (DAS) is an efficient and well-established glenohumeral stabilization technique, offering an arthroscopic alternative to Latarjet and glenoid reconstruction with distal tibial allograft or the iliac crest autograft. DAS is essentially an augmented Bankart procedure and can be performed using transfer of either the long head of the biceps tendon or the conjoined tendon. Both result in similar and acceptable rates of recurrences, complications, return to sport, and subjective shoulder function. However, the effectiveness of Bankart repair on shoulder stability decreases significantly over time, so long-term follow-up evaluations of DAS are required. The best indication for DAS may be anteroinferior shoulder instability with limited anterior bone loss.

Dynamic Anterior Stabilization of the Shoulder: Onlay Biceps Transfer to the Anterior Glenoid Using the Double Double-Pulley Technique

The treatment of anterior glenohumeral instability includes several surgical options, ranging from soft tissue to bony procedures-open or arthroscopic. In arthroscopic dynamic anterior stabilization (DAS) of the shoulder, the long head of the biceps is transferred to the anterior glenoid through a subscapularis tendon split. The biceps may be fixed either in an inlay or in an onlay position. Inlay DAS theoretically increases anterior glenohumeral stability through 3 different effects: the hammock effect, sling effect, and the tensioning effect. Onlay DAS may additionally increase stability through a labroplasty effect, produced by the onlay positioning of the biceps on the anterior glenoid rim. The current technical note presents tips and tricks, and pearls and pitfalls, to reproducibly perform onlay DAS using all-suture anchors and the double double-pulley technique.