Medically reviewed by Nathan Orvets, MD | Reviewed July 2026
Wondering why your shoulder hurts more after you’ve been active, even though you never actually hurt it? In many cases, the answer is shoulder tendinitis. It’s one of the most common reasons patients from the Portland area come see me in Tualatin or Oregon City. Shoulder tendinitis usually develops slowly, often from repeated overhead motion. It can range from a mild ache to pain that keeps you up at night. In this post, I’ll walk through what shoulder tendinitis is, why it happens, and how I generally approach treating it.
Key Takeaways
- Shoulder tendinitis is irritation or swelling of a tendon in the shoulder, most commonly one connected to the rotator cuff.
- It typically develops from repeated overhead activity, though age and posture can play a role too.
- Most cases improve with a non-surgical plan. Surgery is only needed for a small number of patients.
What Is Shoulder Tendinitis?
Shoulder tendinitis means irritation or swelling of a tendon in the shoulder. Usually, it’s one of the rotator cuff tendons or the biceps tendon. Tendons connect muscle to bone, and in the shoulder, they sit in a fairly tight space just under a bony ledge called the acromion. When a tendon becomes swollen, it can rub against nearby bone or tissue every time you lift your arm. That friction is usually where the pain comes from.
There’s a related term worth knowing. Tendinitis technically means active inflammation, and it tends to show up more suddenly. Over time, though, many cases shift into something called tendinosis, which involves small changes in the tendon fibers rather than pure swelling. Both can feel similar, but they may respond a bit differently to treatment. That’s part of why an accurate diagnosis matters.
What Causes Shoulder Tendinitis?
Repeated overhead motion is the most common cause. Swimmers, throwing athletes, painters, and anyone who works overhead all place repeated stress on the same tendons. Over months or years, that stress can outpace the tendon’s ability to repair itself. Age plays a role too, since tendons naturally lose some elasticity and blood supply as we get older. That’s part of why shoulder tendinitis becomes more common after age 40.
Posture matters more than most people expect. A rounded-shoulder posture, common in people who sit at a desk for long hours, can narrow the space where the rotator cuff tendons sit. That can make irritation more likely, even without an obvious overuse activity. A past shoulder injury, whether from a fall, a sport, or a work incident, can also leave a tendon more vulnerable down the road.
Certain activities carry more risk simply because of how the shoulder moves during them. Swimmers repeat the same overhead stroke thousands of times a week. Throwing athletes generate a lot of force through the shoulder in a split second. Even everyday tasks, like painting a ceiling or reaching for a high shelf at work, can load the tendon repeatedly over the course of a day.
What I See in My Patients
In my practice, tendinitis shows up in a good number of new shoulder visits. Sometimes it’s on its own, sometimes alongside something else, like impingement. The pattern I notice most is a patient who assumes the pain will pass on its own. By the time they come in, the irritation has often been building for months. I tell my patients the same thing every time. Shoulder tendinitis rarely gets better faster just because you wait longer to deal with it, especially if you aren’t addressing the root cause.
I also see quite a few weekend athletes and gardeners here in the Portland area whose symptoms flare up seasonally. This frequently happens in spring and summer, when overhead activity picks up. Those patients tend to do especially well once we address the pattern early, instead of after months of pushing through it.
Symptoms of Shoulder Tendinitis
The two symptoms I ask about first are pain with overhead motion and pain at night, especially when lying on the affected side. Beyond that, patients commonly describe a dull ache that gets sharper with certain movements, like reaching into a cabinet or putting on a jacket. Some weakness can show up too, though it’s usually mild compared to what you’d feel with a rotator cuff tear.
Shoulder tendinitis can also look a lot like impingement or bursitis on the surface. All three tend to flare with overhead reaching. That’s exactly why I don’t rely on symptoms alone. A careful exam usually narrows things down.
How I Diagnose It
Diagnosis starts with a conversation and a physical exam. I look at your range of motion, your strength in specific positions, and whether certain movements reproduce your pain. In many cases, that exam gives me a strong sense of what’s going on. When I want to confirm the diagnosis or rule out a tear, I may order an ultrasound or MRI. Imaging can show tendon thickening, fluid, or a partial tear that isn’t obvious on exam alone.
My Approach to Treatment
I start nearly every case of shoulder tendinitis with a non-surgical approach, and most patients do well with it. That usually means a period of rest from the aggravating activity, physical therapy focused on the rotator cuff and shoulder blade muscles, and anti-inflammatory medication when it makes sense. I’m fairly selective about corticosteroid injections. They can help calm a flare and make physical therapy more comfortable. But I try not to lean on them repeatedly, since frequent injections can weaken tendon tissue over time. In some cases, platelet-rich plasma (PRP), a regenerative medicine option, may be considered.
A good physical therapy program starts with pain control and gentle motion work. From there, it builds toward strengthening the rotator cuff and the scapular muscles, which often get overlooked despite playing a big role in how the tendon gets loaded during daily life.
If a patient hasn’t improved after several months of consistent conservative care, or if imaging shows a rotator cuff tear alongside the tendinitis, that’s when I start discussing surgical options. This might mean arthroscopic debridement or subacromial decompression. Surgery is uncommon for tendinitis alone in my practice, but it remains worth discussing once conservative care has had a fair chance.
Preventing Shoulder Tendinitis
A few habits support lowering your risk:
- Warm up before overhead activity, especially sports like swimming, tennis, or golf.
- Build rotator cuff and scapular strength before pain starts, not just after.
- Take breaks during repetitive overhead tasks at work or around the house.
- Pay attention to posture, particularly if you spend most of your day at a computer.
Summary
Shoulder tendinitis is common and treatable. In my experience, it responds best when it’s addressed early, rather than after months of working around the pain. If overhead motion or nighttime discomfort has been bothering your shoulder for more than a couple of weeks, I’d encourage you to schedule an evaluation rather than waiting it out. Reach out to our Tualatin or Oregon City office so we can get you a proper diagnosis and a treatment plan built around your activity level and goals.
Frequently Asked Questions
Is shoulder tendinitis the same as a rotator cuff tear?
No, though the two are related. Tendinitis involves irritation of a tendon, while a rotator cuff tear involves an actual break in the tendon fibers. Chronic, untreated tendinitis can sometimes progress toward a tear, which is one reason I recommend addressing it early.
How long does shoulder tendinitis usually take to heal?
It varies by patient, but many people see real improvement within six to twelve weeks of starting a structured physical therapy program. More long-standing cases may take longer. Staying consistent with the exercises tends to matter more than any single treatment.
Can I keep exercising with shoulder tendinitis?
Often, yes, with some changes. I generally suggest avoiding the specific overhead motions that bring on your pain, while continuing activities that don’t aggravate the tendon. Your physical therapist can help figure out which movements are safe during recovery.
When should I see a doctor for shoulder tendinitis?
I’d recommend getting evaluated if your pain has lasted for several weeks, if it’s disrupting your sleep, or if you notice new weakness.
