The increase of the population life expectancy and the active lifestyle adopted in recent years have contributed to the higher incidence of rotator cuff injuries. For large (>3 cm) and extensive (>5 cm) injuries of the rotator cuff, even after complete or partial repair, the chances of failure reach 94%.

An alternative in rotator cuff injuries is the use of the long head of the biceps (LHB) as an autologous graft to increase the healing rate and the final outcomes.

The primary objective is to compare the functional results, according to the ASES score, between patients who use or not the long head biceps brace for complete repairs of large and extensive rotator cuff tears.

The secondary objectives are to compare the groups according to structural results by MRI and functional results by the UCLA score.

A prospective randomized study will be carried out in a 1:1 ratio between groups. Patients with large and extensive rotator cuff injuries will be selected at the Shoulder and Elbow clinic of Pedro Ernesto University Hospital (HUPE-UERJ), during outpatient care.

Patients with an intact long head of the biceps will be randomized into two groups, according to the use or not of the tendon: complete repair with LHB tendon reinforcement and complete repair without reinforcement. All patients will be operated by the same surgeon.

All selected patients will be explained what the research is about by a research assistant not involved in the treatment and will be offered the option to participate or not.

The "American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form" (ASES) scale will be adopted as the primary outcome. The "Modified University of California at Los Angeles Shoulder Rating Scale" (UCLA) and the assessment of tendon healing with magnetic resonance imaging at 6 months after surgery, using the classification of Sugaya et al. will be secondary outcomes.

Inclusion Criteria:

• Long head tendon of biceps intact;
• Large or extensive posterosuperior rotator cuff injuries according to the classification of DeOrio and Cofield;20
• Fatty degeneration of the ≦2 supraspinatus muscle according to the classification of Goutallier.21

Exclusion Criteria:

• Active or previous infection in the affected shoulder;
• Patients unable to understand preoperative questionnaires;
• Patient who does not undergo at least 1 postoperative evaluation.
• Injury where complete repair of the rotator cuff is not possible;
• Rupture of the LHB tendon diagnosed intraoperatively.