Questions & Answers · Shoulder
What is a reverse shoulder replacement — and why would I need one?
A reverse shoulder replacement swaps the positions of the ball and socket, letting your big deltoid muscle power the arm when the rotator cuff no longer can. It's the answer for shoulders with both arthritis and a failed rotator cuff — cases where a standard replacement wouldn't work because the muscles that drive it are gone.
Why reversing the joint works
A normal shoulder needs the rotator cuff to hold the ball centered while the deltoid raises the arm. When the cuff fails permanently, the ball rides up, the joint grinds, and lifting the arm can become impossible — the combination called cuff tear arthropathy. Flipping the geometry gives the deltoid the leverage to do both jobs. Engineering, not magic — and it's turned thousands of "frozen at the side" arms back into arms.
Who typically needs one
- Arthritis + a big, irreparable cuff tear — the classic case.
- Certain complex fractures in older patients, where repair odds are poor.
- Failed prior surgery — some revisions are best served reverse. Dr. Chin's complex-shoulder practice lives here.
Cuff intact? Then anatomic replacement is usually the better fit — same page, different operation, and imaging decides.
Medically reviewed by Keith W.V. Johnson, MD, FAAOS · Updated September 28, 2026