The primary objective of this study is to compare the improvement in subject-reported clinical outcomes, for Regenexx SD treatment vs. Exercise Therapy of non-retracted supraspinatus tendon tears, from baseline to 3 months, with continued evaluation of efficacy and durability up to 24 months.

Secondary objectives include evaluation of US evidence of tendon repair; incidence of post-operative complications, adverse events, re-injections, and surgical intervention; change in pain score and use of pain medications.

Prospective, randomized, controlled to include 34 subjects treated with Regenexx SD and 17 subjects treated with Exercise Therapy alone (2:1 randomization).

Subjects will have a non-retracted supraspinatus tendon tear comprising at least one half the tendon thickness in the anterior-posterior and/or superior-inferior planes as evidenced with positive diagnostic imaging such as arthrogram, ultrasound and/or MR.

Subjects will be enrolled within 60 days prior to Regenexx-SD injection or initiation of exercise therapy and take part in follow-up visits for two years following treatment. A preoperative visit will occur at the time of enrollment; follow-up visits will occur at the clinical site at 6 weeks, 3 months, 6 months, 12 months, and 24 months post injection.

The primary endpoint analysis will be conducted once all subjects reach the 3 month endpoint. At that point, subjects enrolled in the Exercise Therapy group will be given the option of crossing over to the Regenexx SD treatment groups. Subjects will continue to be followed through the 2 year endpoint with data analysis performed at the 1 year and 2 year time points.

Subjects will complete the study following the 2 year follow-up visit.

Inclusion Criteria:

• Physical examination consistent with Rotator Cuff tear
• Unremitting pain in the affected shoulder for at least 3 months
• Significant functional disability related to pain, lack of strength, or other shoulder symptoms
• Positive diagnostic imaging, which may include arthrogram, ultrasound and/or MR, on the affected shoulder indicating a non-retracted supraspinatus tendon tear comprising at least one half the tendon thickness in the anterior-posterior and/or superior-inferior planes
• Reasonable movement of the non-treated arm, defined as a shoulder elevation of equal or more than 90°, and able to perform (post-injection) exercises
• Is independent, ambulatory, and can comply with all post-operative evaluations and visits

Exclusion Criteria:

• A massive rotator cuff tear as demonstrated by Grade 3 or less muscle strength on testing internal and external rotation of the affected shoulder
• Previous surgery to the affected shoulder
• Concomitant tears of biceps tendons
• Grade 2 or greater SLAP tear
• Type 3 acromion
• Significant bone spur in subacromial space
• Inflammatory or auto-immune based joint diseases or other upper extremity pathology (e.g., rheumatoid arthritis, systemic lupus erythematosus, psoriatic arthritis, polymyalgia, polymyositis, gout pseudogout)
• Quinolone or Statin induced myopathy/ tendinopathy
• Kellgren-Lawrence grade 2 or greater glenohumeral osteoarthritis
• Adhesive capsulitis (mild or severe)
• Symptomatic cervical spine pathology (e.g. radicular cervical pain)
• Severe neurogenic inflammation of the cutaneous nerves about the shoulder
• Shoulder instability requiring surgical stabilization
• Contraindications for MRI
• Tested positive or has been treated for a malignancy in the past or is suspected of having a malignancy or is currently undergoing radiation or chemotherapy treatment for a malignancy anywhere in the body, whether adjacent to or distant from the proposed injection site
• Condition represents a worker's compensation case
• Currently involved in a health-related litigation procedure
• Is pregnant
• Bleeding disorders
• Currently taking anticoagulant or immunosuppressive medication
• Use of chronic opioid