Reverse total shoulder arthroplasty replaces the shoulder joint with implants that reverse the normal ball-and-socket anatomy: the ball is attached to the glenoid, and the socket is attached to the humerus. This biomechanical change allows the deltoid to elevate the arm without requiring a functional rotator cuff. RTSA is the most reliable treatment for patients with rotator cuff arthropathy, massive irreparable rotator cuff tears, and other conditions where the rotator cuff cannot be restored.
What Is Reverse Total Shoulder Arthroplasty?
In a normal shoulder, the rotator cuff keeps the humeral head centered on the glenoid as the deltoid lifts the arm. When the rotator cuff is destroyed (as in chronic massive tears or rotator cuff arthropathy), the humeral head migrates upward and the deltoid loses its mechanical advantage. The result is pain, weakness, and inability to lift the arm against gravity.
RTSA solves this by reversing the joint anatomy. A glenosphere (metal ball) is attached to the glenoid. A humeral cup (polyethylene socket) is attached to the humerus. This shifts the center of rotation medially and inferiorly, increasing the deltoid’s mechanical advantage so it can elevate the arm without rotator cuff support.
Who Is a Candidate?
RTSA is the procedure of choice for:
- Rotator cuff arthropathy (advanced shoulder arthritis with irreparable rotator cuff)
- Massive irreparable rotator cuff tears with pseudoparalysis
- Failed prior shoulder arthroplasty in selected patients
- Complex proximal humerus fractures in older patients with poor bone quality
- Severe glenoid bone loss not amenable to anatomic arthroplasty
- Tumor reconstruction in select cases
Patients with intact rotator cuff function and adequate bone stock are typically better served by anatomic total shoulder arthroplasty.
How the Procedure Is Performed
RTSA is performed through an incision at the front or top of the shoulder, depending on surgical approach. The deltopectoral or superolateral approach is selected based on patient anatomy and any prior surgery. The deltoid is preserved because it becomes the workhorse muscle after RTSA.
The glenoid is prepared with reaming, and a metal baseplate is fixed with screws. A glenosphere (ball component) is attached to the baseplate. The humerus is prepared with a canal reamer, and a stemmed humeral component is implanted with a polyethylene cup that articulates with the glenosphere.
The reversed geometry restores stability without requiring rotator cuff function. Trial components are tested for stability, range of motion, and tension before final implantation.
Recovery and Rehabilitation
Recovery is generally faster than after anatomic arthroplasty because the rotator cuff is not under repair tension:
- Hospital stay of one to two days
- Sling protection for two to four weeks
- Passive and assisted active motion beginning within days
- Active motion at three to four weeks
- Strengthening at six to eight weeks
- Return to most daily activities by two to three months
- Return to low-impact sport at three to four months
Risks and Outcomes
Risks specific to RTSA include scapular notching (wear of the inferior glenoid rim), instability or dislocation of the prosthesis, acromial stress fracture, and infection. Glenoid bone preparation must be precise to optimize component position and minimize notching. Component design has improved significantly to reduce these risks.
Pain relief and restoration of active elevation are reliable in appropriately selected patients. Most patients regain forward elevation to 120 to 140 degrees, sufficient for hair care, dressing, and reaching shelves. External rotation recovery is more variable and depends on the status of the remaining rotator cuff (especially the infraspinatus and teres minor).
Why Dr. Chudik for RTSA
Dr. Chudik treats the full range of indications for reverse total shoulder arthroplasty, including primary cases, complex fracture patterns, and revision arthroplasty. His experience across the spectrum of shoulder pathology, including the rotator cuff disease that often precedes RTSA candidacy, informs implant selection and surgical planning. He has performed shoulder arthroplasty for more than two decades.