Arthroscopic Stabilization of Anterior Shoulder Instability With Subcritical Glenoid Bone Loss (SHIELD)

Recurrent anterior shoulder instability is a common condition among young and active patients, with a significant impact on function and a high risk of recurrence in the absence of appropriate management. Quantifying glenoid bone loss has become a central component of the treatment strategy, with losses exceeding 20 % traditionally considered critical and requiring a coracoid transfer according to the Latarjet procedure. Recent data have, however, shown that so-called "subcritical" bone loss, ranging from 13.5 to 20%, may already be associated with unfavorable clinical outcomes, particularly in highly active patients. These patients most often present with associated humeral lesions, such as Hill-Sachs lesions, and sometimes other concomitant lesions such as Humeral Avulsion of the Glenohumeral Ligament, underscoring the need for a comprehensive therapeutic approach.

Two arthroscopic techniques are currently used for this indication. The arthroscopic Latarjet procedure restores glenoid bone stock and improves dynamic stability through the combined effect of the bone block and the sling, while offering reduced morbidity compared to the open approach. Dynamic anterior stabilization (DAS), on the other hand, involves transferring the long biceps tendon to the anterior glenoid rim to replicate the sling effect in a less invasive manner, while preserving the pectoralis minor and the thoracoacromial pedicle and reducing the risk of neurological complications.

Although both techniques have shown low recurrence rates and functional improvement in the short and medium term, no Level I randomized prospective study has directly compared their outcomes in patients with subcritical glenoid bone loss and combined lesions, as the available data are primarily derived from retrospective studies or case series.

Due to the biomechanical differences between the two techniques, the associated rehabilitation protocols also differ. Thus, this study compares not only the surgical procedures themselves, but two comprehensive therapeutic strategies that include both surgery and rehabilitation.

This project aims to determine whether, in these patients, treatment with DAS yields functional outcomes comparable to those of treatment with arthroscopic Latarjet surgery while reducing morbidity and the risk of overtreatment. The evaluation will be based on validated functional and quality-of-life scores. The primary outcome measure will be the WOSI score. The results of this study could help refine surgical indications and optimize care for a population that is predominantly young and active.