LifeNet: Extracellular Matrix Graft in Rotator Cuff Repair

Inclusion Criteria: * Patients with a large (2.5-5 cm) to massive (\>5 cm) rotator cuff tear who will be undergoing open or arthroscopic repair. The cuff tear size will be determined on either pre-operative magnetic resonance imaging (MRI), or ultrasound (US), or intra-operative measurements, or computerized tomography (CT). * Patients who are willing and able to provide written informed consent for their involvement in the study. * Patients who meet criteria for RCR surgery * Patients older than 18 years of age Exclusion Criteria: * Those with a known sensitivity to materials of porcine origin. * Patients with addiction to illegal drugs, solvents or alcohol who are actively using or have previously attempted and failed a treatment program. * Patients with bacteremia, a systemic infection, or infection of the surgical site. * All those who are prisoners. * Patients who are pregnant or nursing. * All those with a condition that may limit a patient's ability to finalize the study or that may cause an undue risk to the patient's health and well-being.