Rotator Cuff Sparing Total Arthroplasty

Design: Prospective, randomized clinical trial, of 120 patients requiring a total shoulder
replacement (TSR).

Purpose: To collect and evaluate long-term clinical data on patients whose total shoulder
replacement (TSR) is performed using the traditional surgical approach (called the
subscapularis release approach) as compared to patients who have a TSR procedure done using
a newer surgical approach (called the rotator cuff sparing approach).

For patients with arthritis, TSR can successfully improve pain and restore function. As a
result, TSR has become the treatment of choice for patients with shoulder arthritis. Despite
these generally good outcomes, however, there are concerns that rotator cuff function is
suboptimal after surgery. One of the rotator cuff tendons is usually cut during the TSR
procedure to insert the prosthesis and then repaired at the end of the surgery. If the
tendon does not heal adequately, patients may experience persistent weakness, pain, and even
failure of the replacement. Recently, a surgical technique called rotator cuff sparing TSR
has been described where the procedure can be performed without ever cutting any of the
rotator cuff tendons. As such, there should be minimized risk to the rotator cuff function
after the surgery. Our study proposes to enroll two groups of patients with shoulder
arthritis. The first group will be treated with the traditional TSR procedure. The second
group will be treated with this new rotator cuff sparing surgical technique for TSR where
the rotator cuff is never violated. After surgery, we will examine motion, strength, and
functional use of the shoulder. In addition, we will specifically test the rotator cuff
strength after the surgery. In this fashion, we plan to test the hypothesis that rotator
cuff sparing TSR can improve the rotator cuff function while maintaining the excellent pain
relief and motion that is normally observed after the traditional TSR procedure.

Enrollment: A total of approximately 120 subjects will be enrolled and treated at NYU
Hospital for Joint Diseases. Subjects participating in the study will be randomly assigned
to have their total shoulder replacement done using the traditional surgical approach
(called the subscapularis release approach) or by the newer surgical approach (called the
rotator cuff sparing approach). For each patient, a number will be created by a random
number generator. Patients randomized to the even number (2) will receive a traditional TSA
procedure that includes incision and repair of the subscapularis tendon during the
procedure. Patients randomized to the odd number (1) will receive the rotator cuff sparing
TSA. Regardless of the procedure, patients will remain "blind" to the type of procedure they
received until completion of their 2 year follow up.

Follow-Up Requirements: Office Visits: Patients' participation will involve five (5) office
visits (after surgery) over a period of two (2) years. At each visit, as part of the
patients' regular care, they will have standard x-rays of their shoulder. All patients will
complete self-administered questionnaires to assess the clinical outcome of the surgery and
patients satisfaction. The patient administered outcome questionnaires will include the
SF-12, and Patient Assessment Case Report Form.

Inclusion Criteria:

- Patient is indicated for shoulder joint replacement

- Patient is at least 21 years of age

- Patient is expected to survive at least 2 years beyond surgery

- Patient is willing to participate by complying with pre-and post-operative visit
requirements

- Patient is willing and able to review and sign a study informed consent form

Exclusion Criteria:

- Prior arthroplasty in the affected shoulder.

- Significant deformity of the proximal humerus that requires a custom made implant or
where osteotomy of the shaft and / or the tuberosity has to be considered.

- Significant medial erosion of the glenoid such that lateral edge of the humeral head
lies medial to the lateral rim of the acromion.

- Significant injury to the brachial plexus

- Inability or unwillingness to participate in the post operative evaluation for the
entire 24 months period.

- Pregnant and lactating women will be excluded