Patients will be randomized to receive HEALICOIL™ REGENESORB (the study anchor) or TWINFIX Ultra HA, a similar comparative product, for use in the repair of their shoulder injury. They will be asked to complete questionnaires throughout the study and will receive an MRI, CT and multiple ultrasound images. The MRIs and radiographs will be used to assess bony ingrowth at the repair site, and the ultrasound to assess repair success rate of the rotator cuff. The clinical and radiological outcomes will be compared between the study and control groups. It is hypothesized that there will be 85% high quality ossification at anchor site for HEALICOIL REGENESORB and 49.9% high quality ossification for TWINFIX Ultra HA at 24 months.

Inclusion Criteria:

• Male or female, aged 35 to 75 years at the time of surgery.
• Willing and able to give voluntary informed consent to participate in this investigation.
• Full thickness tear of the rotator cuff
• Tear requires repair within one year of initial diagnosis.
• Tear must be anatomically repairable (must be able to get tendon back to the medial position on the footprint and at least back to the tuberosity).
• Willing and able, in the opinion of the Investigator, to cooperate with study procedures, and willing to return to study site for all required post-operative study visits.

Exclusion Criteria:

• Evidence of acute trauma including fracture or dislocation of the shoulder joint.
• Chronic retraction.
• Evidence of active infection, osteomyelitis, sepsis or distant infection, which could spread to the index joint.
• Subject has had previous rotator cuff, arthroplasty or fracture procedures on the operative shoulder.
• Subject has had acromioplasty or diagnostic arthroscopy on the operative shoulder within one (1) year prior to scheduled surgery date.
• Evidence of osteomalacia or other metabolic bone disorder(s), which may impair bone or soft tissue function.
• Evidence of other significant shoulder pathology including (Type II-IV lesion, Bankart lesion, Hill Sachs lesion).
• Patient has grade 4 changes to articular cartilage in operative shoulder
• Inflammatory arthropathies.
• Significant muscle paralysis of the shoulder girdle.
• Painful pathologies of the cervical spine.
• Comminuted bone surface, which would compromise secure anchor fixation.
• Non-surgical rotator cuff associated treatment, such as corticosteroid injection, within one (1) month prior to scheduled surgery date.
• Participating in another investigational trial or ongoing study that would interfere with the assessment of the primary and secondary outcomes.
• Female patient who is pregnant, nursing, or of childbearing potential while not practicing effective contraceptive methods.
• Major psychiatric illness, developmental handicap or inability to read and understand the English language.
• Major medical illness that would preclude undergoing surgery.
• Known to be involved in any active injury litigation claims relating to the study shoulder.
• Unwilling or unable to be assessed according to study protocol for two years following surgery.
• Patient requires a concomitant SLAP repair procedure in operative shoulder.
• Surgeon plans to use a Platelet Rich Plasma product or another therapy intended to augment healing of the rotator cuff in the study procedure.
• Protocol specified surgical technique cannot be followed for this subject.
• Rotator cuff repair will be done via open (as opposed to arthroscopic) procedure.
• Any other reason (in the judgment of the investigator).

Adverse events were collected and assessed from time of surgery to two year final study follow-up