Little evidence exists to guide treatment in patients with massive irreparable rotator cuff tears (MRCTS). Arthroscopic partial rotator cuff repair (PRCR) has the longest record of use. The new technique of superior capsular reconstruction (SCR) has more recently been described. Despite high enthusiasm for this technique, its effectiveness, cost and safety profile have not been established.

The long-term goal of this study is to perform a multicenter randomized control trial to evaluate the effectiveness of SCR compared to PRCR in patients with MRCTS. The current study is a pilot required to support the development of an expanded formal clinical trial.

The current study seeks to improve the management of patients suffering from massive irreparable rotator cuff tears. Despite several available surgical options, no level 1 evidence or randomized clinical trials have been performed in this patient population to date. Arthroscopic partial rotator cuff repair (PRCR) is arguably the gold-standard surgical option with the longest record of use. The new technique of superior capsular reconstruction (SCR) has also emerged with early biomechanical and case series showing promising results. SCR has quickly made its way into clinical practice in North America. Despite this, the effectiveness, cost, and safety profile has not been established for this procedure. As such, patients with massive irreparable rotator cuff tears are in need of high level evidence to support surgical decision making, particular with regards to the proliferation of SCR surgery.

This pilot study is a randomized, controlled, double-blinded trial comparing superior capsular reconstruction using dermal allograft with arthroscopic partial repair in patients with massive irreparable rotator cuff tears. In this study, "double-blind" includes study patients and outcome assessors. Randomization will occur intra-operatively once a tear is determined to be irreparable.

This trial will be conducted at 7 sites and involve 7 surgeons. Surgeons must meet eligibility requirements to participate (shoulder or sports fellowship-trained, minimum of 3 SCR procedures, and 25 arthroscopic rotator cuff repair procedures in the past year). A member of the local research team will pre-screen consults of eligible patients. Full eligibility will be determined during the primary appointment with an orthopaedic surgeon. Baseline data will be recorded following informed consent. Postoperative outcomes will be measured during regularly scheduled clinic visits (6 weeks, 3 months, 6 months, 1-year and 2-year post-surgery).

Prior to surgery, patients will have informed consent for both procedures, with randomization to be performed intraoperatively. Based on initial arthroscopic assessment of the shoulder, patients that have a confirmed irreparable tear will be randomized into one of two groups: arthroscopic partial repair or superior capsular reconstruction. Surgical techniques will be standardized. Allocation will be concealed using a centralized 24-hour computerized randomization system that will allow Internet-based allocation. A random number generator will be used to create a 1:1 allocation scheme for randomization of the patient into one of the two treatment groups. The post-operative therapy regimen will be the same for each group.

Inclusion Criteria:

• Symptomatic shoulder pain and/ or weakness (regardless of baseline range of motion/ psuedoparalysis)
• Massive rotator cuff tear, identified by MRI as being greater than 4 cm in greatest diameter, and involvement of the entire supraspinatus and infraspinatus.
• Failure of at least a 3 month trial of non-surgical treatment including physiotherapy and activity modifications
• Irreparable tear determined intra-operatively using standard arthroscopic techniques
• Informed consent obtained

Exclusion Criteria:

• Absence of subscapularis muscle insertion, or irreparable subscapularis tear
• Advanced rotator cuff tear arthropathy (Hamada Grade 3+) or glenohumeral osteoarthritis (Samilson-Prieto grade 2+)
• Acute tears (within 6 months)
• Neurologic injury causing paralysis of affected shoulder / arm
• Any previous surgery to the affected shoulder
• Limited life expectancy due to significant medical co-morbidity or medical contraindication to surgery (ASA Grade IV or higher)
• Anticipated problems with ability to maintain follow-up in the judgement of the investigators (ie. patients with no fixed address, etc.)
• Are there any non-orthopedic comorbidities that put the patient at significant risk?