Overview
The ball of the humerus and the shallow glenoid socket are lined with smooth cartilage that lets them glide with almost no friction. Arthritis is the loss of that cartilage. As it wears, the bone beneath thickens and grows spurs, the socket wears into a shape the ball no longer fits, the capsule tightens, and the shoulder becomes painful and stiff and grinds with movement. It is less common than hip or knee arthritis, but it takes away the overhead reach and rotation that daily life depends on.
Two questions decide treatment: how much the arthritis limits the patient in pain, sleep and function, which decides whether it is time to consider replacement at all; and the condition of the rotator cuff, because a shoulder with an intact cuff and one whose cuff has torn away are replaced with different implants.
Common Symptoms
- A deep ache that is worse with use and, as the arthritis advances, present at rest and at night
- Progressive stiffness: loss of the ability to turn the arm outward, reach overhead, or reach behind the back
- Grinding, clicking or crunching with movement that can sometimes be felt with a hand on the shoulder
- In rotator cuff arthropathy, weakness and an inability to lift the arm away from the body at all
Stiffness with grinding in a patient over 60 is arthritis unless the X-ray shows otherwise. A stiff shoulder with a normal X-ray, particularly between 40 and 60, is frozen shoulder, which can be indistinguishable on exam. Weakness lifting the arm without much stiffness suggests a rotator cuff tear, and pain confined to the end of the collarbone is AC joint arthritis, a much smaller problem treated differently.
Causes & Risk Factors
Primary osteoarthritis is simple wear, most often appearing after 60 and running in families. Post-traumatic arthritis follows a fracture through the joint surface or a history of dislocations; a shoulder that dislocated repeatedly in a patient's twenties can wear its socket by the forties, which is one argument for early stabilization. Rotator cuff arthropathy develops when a large, long-standing cuff tear lets the humeral head migrate upward and grind against the acromion, and it is the usual reason a reverse replacement is chosen. Rheumatoid arthritis, avascular necrosis, and years of heavy overhead labor account for the rest.
How It Is Diagnosed
Dr. O'Donnell measures passive and active motion in each direction; loss of external rotation with the arm at the side is the finding most characteristic of glenohumeral arthritis. He feels for crepitus with rotation, then tests each rotator cuff tendon: the empty-can test and resisted external rotation for the supraspinatus and infraspinatus, the belly-press and lift-off tests for the subscapularis. Cuff strength is the exam finding that most influences the choice of implant.
X-rays make the diagnosis: an AP view shows joint-space narrowing, spurs and sclerosis, and an axillary view shows how far the socket has worn and whether the head has slipped backward on it. Upward migration of the head toward the acromion means the cuff is torn. CT is ordered when replacement is being planned, to measure glenoid bone loss and template the implant; MRI is added when the cuff's condition is uncertain, since it decides between an anatomic and a reverse design. Visiting patients can upload existing imaging through mymedicalimages.com.
Treatment Options
Non-operative care
Arthritis is managed without surgery until pain and function justify replacement, and for many patients that is years. The approach is to keep the shoulder moving and reduce the load on it: a home stretching program to preserve rotation and elevation, cuff and shoulder-blade strengthening in comfortable ranges, activity modification such as swapping the bench press for cable work, and anti-inflammatories in short courses. A corticosteroid injection into the joint under ultrasound guidance gives several months of relief in most patients and can be repeated a few times a year. None of these change the cartilage. Arthroscopic debridement can give a younger patient with early arthritis and mechanical catching a few years of relief, but is not a substitute for replacement in an advanced joint.
Anatomic and reverse total shoulder replacement
When pain limits sleep and daily life despite the measures above, Dr. O'Donnell recommends shoulder replacement. The choice of implant depends on the cuff. If the rotator cuff is intact and working, an anatomic replacement resurfaces the ball with a metal head and the socket with a polyethylene cup, reproducing normal anatomy and giving the best motion and strength. If the cuff is torn beyond repair, or the socket is so worn that an anatomic cup would loosen, a reverse replacement swaps the geometry, putting the ball on the socket side and the cup on the humerus so that the deltoid alone can raise the arm. Both reliably relieve pain; the anatomic replacement generally gives better rotation and lifting, and the reverse carries a permanent recommendation to keep lifting to light loads.
Recovery & What to Expect
The two implants are protected differently early on. An anatomic replacement needs the subscapularis tendon, detached to enter the joint and repaired at the end, to heal before it is loaded, so external rotation is limited. A reverse replacement has no tendon repair to protect but can dislocate in one position, so reaching behind the back is avoided.
| Phase | Timing | Anatomic replacement | Reverse replacement |
|---|---|---|---|
| Protected motion | Weeks 0–6 | Sling 3–4 weeks. Passive flexion to about 120°, external rotation limited to 30°; no resisted internal rotation, no reaching behind the back, no weight through the arm. | Sling 3–4 weeks. Passive flexion to about 120°, external rotation to 30°; no combined extension, adduction and internal rotation, no reaching behind the back, no weight through the arm. |
| Active motion | Weeks 6–12 | Active-assisted then active motion in all planes; rotation progressed to full; light cuff and scapular work. | Active elevation with deltoid activation to 100–120°; scapular strengthening; still no extension behind the body. |
| Strengthening | Weeks 12–16 | Light resistive cuff, deltoid and scapular strengthening; functional reaching. | Progressive deltoid and periscapular strengthening; functional reaching and elevation tasks. |
| Functional return | Months 4–6 | Golf, swimming and doubles tennis as cleared. | Daily function and light recreation; lifting limited to light loads long term. |
Desk work is possible within one to two weeks, driving once the sling is off and rotation is comfortable at about 4 to 6 weeks, and golf, swimming and doubles tennis at 4 to 6 months. The protocols are available as PDFs: anatomic total shoulder replacement and reverse total shoulder replacement.
Frequently Asked Questions
What is the difference between an anatomic and a reverse shoulder replacement?
An anatomic replacement resurfaces the ball and socket in their natural arrangement and relies on the rotator cuff to move the arm; it is chosen when the cuff is intact and gives the best rotation and strength. A reverse replacement puts the ball on the socket side and the cup on the arm so the deltoid raises the arm on its own; it is chosen when the cuff is torn beyond repair or the socket is badly worn.
Can shoulder arthritis be treated without surgery?
Yes, often for years. Stretching to keep motion, cuff and shoulder-blade strengthening, activity changes, short courses of anti-inflammatories and ultrasound-guided steroid injections control symptoms in most patients with early to moderate arthritis. None of these regrow cartilage. Replacement is discussed when pain disturbs sleep and daily tasks despite them.
How long do I wear a sling after shoulder replacement?
Three to four weeks, with the sling removed several times a day for pendulums and passive motion from the first days. After an anatomic replacement, external rotation is limited to 30 degrees for 6 weeks to protect the repaired subscapularis tendon; after a reverse, reaching behind the back is avoided for the same period.
When can I play golf or tennis after a shoulder replacement?
Putting and chipping at about 3 months, full golf, swimming and doubles tennis at 4 to 6 months once motion is comfortable and strength has returned. Singles tennis and heavy overhead lifting are discouraged after a reverse replacement, which carries a long-term recommendation to keep lifting to light loads.
How long does a shoulder replacement last?
Most modern shoulder replacements are still functioning well at 10 to 15 years, and many last longer. Loosening of the socket component is the most common reason for revision. Avoiding repetitive heavy lifting and impact protects the implant, which is why low-impact sports are the ones cleared afterward.
This page is for general education and is not a substitute for a medical evaluation. Treatment recommendations depend on your individual diagnosis and goals. Kevin O'Donnell, MD sees patients from Coral Gables, Miami, Brickell, Pinecrest and Coconut Grove at 475 Biltmore Way, and out-of-town patients by telemedicine.