How do I know it is shoulder arthritis and not my rotator cuff or my neck?

Three problems hide behind the word shoulder, and each one has a different fix. Arthritis lives inside the joint. It aches deep in the back of the shoulder, it grinds, and it steals rotation. You notice it reaching for a back pocket, a seat belt or a bra strap. It often wakes you when you roll onto that side.

A rotator cuff problem hurts on the outside of the upper arm. It flares with lifting overhead, and the arm still turns well when someone else moves it for you. Pain from the neck is a third story. It runs past the elbow, it may tingle, and it changes when you turn your head. That one is covered on our cervical radiculopathy page.

An X-ray shows the narrowed joint space and the bone spurs. The exam shows which motions are lost. When the source is still unclear, a numbing injection placed in the joint under image guidance settles it within the hour.

Why does shoulder arthritis keep getting worse?

Cartilage has no blood supply. It eats by motion. Each time the shoulder moves, joint fluid is pressed in and out of the cartilage like water through a sponge. A stiff shoulder moves less, so the cartilage eats less, so it thins faster. Pain makes you guard the arm, and guarding makes the stiffness worse. That loop is the disease.

Two things load the loop. The first is an old injury. A dislocation, a fall on the ice, a fracture near the joint or a seat belt that caught the shoulder in a crash can change how the ball sits in the socket for good. Arthritis that shows up ten years after an injury is still that injury. The second is blood sugar. High insulin and sugar stiffen collagen in cartilage, tendon and the joint lining. That is why stiff, painful shoulders cluster in people with diabetes. We check that bloodwork on purpose. Our metabolic health and pain page explains why.

Why did my shoulder cortisone shot stop working?

Cortisone calms the inflamed lining of the joint. It does nothing for the cartilage or the bone. So the first shot often works well, the second works less, and the third buys a few weeks. Each shot also raises blood sugar for several days. That shrinking window is a signal, not a personal failure. We explain how to read it on when injections stop working.

What do PRP and bone marrow concentrate do in an arthritic shoulder?

Orthobiologics use your own tissue to change the chemistry inside the joint. Each one sends a different crew.

Platelet-rich plasma (PRP)

We draw your blood, spin it, and concentrate the platelets. Platelets carry growth factors that quiet the inflamed lining and slow the enzymes that eat cartilage. In 2026, an international panel of 24 orthobiologic experts reached formal agreement on statements covering PRP for shoulder arthritis, along with the knee and hip.

Bone marrow concentrate

Marrow is drawn from the back of the pelvis under local anesthetic, then concentrated. It carries repair cells and signals that platelets do not. We reach for it in a more worn joint, or when the bone under the cartilage is part of the pain.

Microfragmented fat

A small amount of your own fat is washed and broken into tiny clusters. It adds cushion and a slow, steady signal. It is one more option, chosen by the joint and not by habit.

A 2025 review of 1,125 adults with shoulder arthritis found that joint injections do relieve symptoms. We use what the shoulder evidence supports, and we measure your response.

Why do platelet dose and placement decide the result?

PRP is not one product. A weak spin can leave barely more platelets than plain blood. In the knee trials, results tracked the platelet concentration actually delivered. We prepare a high dose for that reason.

Placement matters just as much. The shoulder joint sits behind a wall of muscle. An injection by feel can land in the muscle and treat nothing. We guide every shoulder injection with ultrasound or X-ray, as described on our image-guided joint injections page.

What happens on the day, and after?

You stay awake. We use local anesthetic, not sedation, and most people drive themselves home. Expect soreness for about 48 hours. Then the rehab starts, and the rehab is half the treatment. We rebuild the rotator cuff and the muscles around the shoulder blade, because they steer the ball in the socket. We restore the reach the joint lost. And we work on the blood sugar and sleep that set your healing budget. How many injections you need follows how your shoulder responds. There is no preset series.

When is a shoulder replacement the right call?

Some shoulders are finished. The ball has flattened, bone is worn away, or you cannot lift the arm to your mouth. For that joint, replacement is the right operation, and we say so. We coordinate the surgical referral ourselves. For everyone else, the goal is time: more years with your own shoulder, less pain and fewer pills.

Frequently asked questions

Can PRP regrow cartilage in my shoulder?

Do not count on new cartilage. The goal is a calmer joint, less pain, better motion and more years before surgery. If a clinic promises you new cartilage, ask them for the scan that proves it.

How many PRP injections will my shoulder need?

It depends on your response. Some shoulders do well with one. Others need a second after we see how the first one did. We decide that together at follow-up, not on a calendar.

Will I be put to sleep for a shoulder injection?

No. We numb the skin and the path to the joint with local anesthetic. You are awake the whole time, and most people drive themselves home.

Does insurance pay for shoulder PRP?

Most plans do not cover PRP. That is a budgeting choice about what a plan funds, not a verdict on the treatment. HSA and FSA funds can generally be used. We go over your options at the visit.

My shoulder arthritis started after a car accident. Does that change anything?

It can. Arthritis that follows a dislocation or fracture is often younger and more one-sided. Tell us about the injury and bring the old records. Our after a car accident page covers how those cases are documented.

What if my rotator cuff is torn too?

Many arthritic shoulders also have a worn cuff. We treat what the exam and imaging show. Sometimes that means the joint, sometimes the tendon, and sometimes both in one plan.

Related reading

• Image-guided joint injections
• When injections stop working
• Cervical radiculopathy
• Hip arthritis
• Bone-on-bone knee
• Metabolic health and pain