Mesenchymal Stem Cells in Rotator Cuff Repair

Mesenchymal Stem Cells in Rotator Cuff Repair - a Randomized Prospective Study

Randomized clinical study involving 44 patients, evaluating the effect of mesenchymal cells on rotator cuff repair. The primary outcome will be post-operative MRI tendon integrity and secondary outcomes clinical assessment by the UCLA and American Shoulder and Elbow Surgeons (ASES) scales and pain by visual analog scale (VAS).

Rotator cuff tendinopathy is the main cause of shoulder pain and tear of these tendons affects 20% of the population. Although arthroscopic repair leads to satisfactory clinical results, the retear rates varies from 4 to 94%. The main cause of failure after rotator cuff repair is not related to the material used, but to the tissue deficiency and the healing process between the tendon and the bone. After the intervention, the rotator cuff does not restore its original histological characteristics and its fixation occurs through scar tissue with lower biomechanical resistance. There are few clinical studies on the use of mesenchymal cells in rotator cuff repair,, with good results.

The investigators will perform a randomized clinical study involving 44 patients, evaluating the effect of mesenchymal cells on rotator cuff repair. The primary outcome will be post-operative MRI tendon integrity and secondary outcomes clinical assessment by the UCLA and American Shoulder and Elbow Surgeons (ASES) scales and pain by visual analog scale (VAS).

Inclusion Criteria:

• Full thickness posterosuperior rotator cuff tear, of small or medium size, fully repairable at the time of surgery, regardless of size;
• Pain and / or decreased shoulder function for at least 3 months, with no improvement with non-surgical treatment;
• Absence of the following changes in MRI:
• Fat degeneration of the rotator cuff musculature of grade 3 according to the classification of Fuchs (presence of equal or superior amount of fat compared to muscle fibers);
• Absence of the following changes in radiographs
• Advanced glenohumeral arthrosis (grades 2, 3 and 4 of Samilson and Prieto
• Signs of rotator cuff arthropathy, according to Seebauer classification;
• Skeletal maturity;
• Absence of surgeries or previous fractures in the shoulder in question;
• Absence of psychiatric illnesses, fibromyalgia or painful pathologies of the cervical spine;
• Absence of rheumatic diseases or chronic use of corticosteroids;
• Absence of active or recent infection;
• Absence of thrombocytopenia, coagulopathies or chronic use of anticoagulants;
• Absence of vascular or neurological lesions affecting the upper limb;
• Absence of pregnancy;
• Clinical non-compensated comorbidities;
• Chronic use of corticosteroids;
• Consent to free and informed consent;
• Live in Brazil.

Exclusion Criteria:

• Visualization during the operative event of one or more of the findings:
• Irreparable rupture of rotator cuff;
• Subsecapularis tear involving two thirds or more of its extension;
• Need to open surgery.